Effects of Organic Fertilizers on the Quality, Yield, and Fatty Acids of Maize and Soybean in Southeast Kazakhstan
by
, , ,
Maxat Toishimanov
1,2,*
,
Zhulduz Suleimenova
1,
Nurgul Myrzabayeva
1,
Zhanna Dossimova
1,
Aksholpan Shokan
3,
Serik Kenenbayev
1,
Gulvira Yessenbayeva
1 and
Assiya Serikbayeva
1,* 1
Kazakh National Agrarian Research University, Almaty 050010, Kazakhstan
2
Institute of Plant Biology and Biotechnology, Almaty 050040, Kazakhstan
3
Institute of Genetic and Physiology, Almaty 050040, Kazakhstan
*
Authors to whom correspondence should be addressed.
Sustainability 2024, 16(1), 162; https://doi.org/10.3390/su16010162
Submission received: 19 October 2023
/
Revised: 30 November 2023
/
Accepted: 13 December 2023
/
Published: 23 December 2023
(This article belongs to the Section Sustainable Agriculture)
Abstract
:This paper presents the effects of organic fertilizers on the yield, quality, and fatty acid composition of maize and soybean in 2022 in Southeast Kazakhstan. Maize and soybean yields were improved by commercial organic fertilizers. In general, the yield, quality, and fatty acid (FA) parameters of both crops were influenced by various types of organic fertilizers. The application of HansePlant fertilizer allowed for an increase in the yield of maize seed by 47% and soybean by 31%. Organic fertilizers improved the quality parameters fat, protein, fiber, and starch in maize by 35%, 22%, 14%, and 8%, respectively, compared to control samples. In soybean, the parameters fat, protein, and fiber were improved by 20%, 3%, and 11%, respectively. The FA compositions of maize and soybean were analyzed via gas chromatography and with tandem mass spectrometer using a polarity column. Compared with no fertilization conditions, the omega-6/omega-3 ratio showed the lowest value in maize (22.40–123.96) and soybean (3.26–4.07). A study of the fatty acid composition groups compared with different fertilizer treatments was performed.
Keywords:
maize; soybean; yield; fatty acid; protein; fat; gas chromatography; mass spectrometry; organic fertilizer1. Introduction
The growing demand for safe and healthy food has made organic farming a major priority worldwide. It is more profitable and environmentally friendly and produces more nutritious food that contains less pesticide residue [1]. In 2019, organic agricultural product sales reached more than EUR 106 billion in 187 countries, and crop areas increased by 72.3 million hectares [2]. Demand has increased because organic agriculture is more sustainable and beneficial for the environment, food quality, and food safety [3]. The production of organic agricultural products involves minimizing the use of synthetic fertilizers, pesticides, plant growth regulators, and feed additives, as well as complying with special quality standards [4]. The main element of organic agriculture is organic fertilizer—traditional organic fertilizers, primarily manure, litter, humus, and compost, contain weed seeds and pathogenic microflora which do not meet industrial product quality standards [5,6]. Organic fertilizers and biofertilizers are environmentally friendly, effective, less toxic, and easy to use, and they provide soil biodiversity in cultivated areas [7,8]. Unlike chemicals, biological products have pronounced selectivity of action, are recognized as harmless to humans and animals, and quickly decompose in soil [9]. Adequate fertilization and good climatic conditions are necessary to achieve the highest production of good-quality grain [10].
Maize and soybean are among the most important crops in the Republic of Kazakhstan [11]. The world leaders in maize production are the USA (347 million tons), China (254 million tons), and Brazil (101 million tons), and in soybean production, the leaders are Brazil (154 million tons), the USA (116 million tons), and Argentina (27 million tons). In Kazakhstan, the production of maize is 1.12 million tons, and the production of soybean is 0.25 million tons [12]. Organic fertilizers in sustainable agriculture are widely applied to increase maize and soybean yield [13]. Organic fertilizers effectively provide an economical and environmentally friendly means of increasing the quantity and quality of grain by stimulating the emission of plant hormones that retain C and N in the plant biomass and releasing greenhouse gases [14,15]. Biologically active compounds released by organic fertilizers have a positive effect on yield and quality indicators, such as fatty acids, vitamins, amino acids, and polypeptides [16,17,18]. The fatty acid (FA) content of a plant oil is one of the main indicators for classifying oilseed products [19]. Maize oil mainly contains palmitic, oleic, and linoleic acids [20]. Five main FAs, palmitic, stearic, oleic, linoleic, and α-linolenic acids, are commonly found in soybean [21]. The nutritional composition of maize and soybean can be determined using the concentrations of protein, starch, and oil, as well as the contents of various FAs [22,23].
Taking into account changes in weather conditions, organic fertilizers have not yet been used on maize and soybean crops in southeastern Kazakhstan. The purpose of this study was to examine the effects of various types of commercial organic fertilizers by identifying quality, yield, and FAs.
2. Materials and Methods
2.1. Data Collection
Cultivated areas in the Republic of Kazakhstan amounted to 22.9 million hectares in 2021, which is one-fifth of the country’s agricultural territory [24]. As shown in Table 1, agricultural producers in Kazakhstan use small amounts of mineral fertilizers. About 83% of crops are not fertilized at all, although this figure increased more than 2.1 times, reaching 16.6% throughout the country [24]. The main types of fertilizer are nitrogen and phosphorus. On average, only 7–8 kg of active fertilizer per hectare is applied in the country (compared to 145 kg/ha in the USA) [25].
While areas under cultivation for organic products are increasing all over the world, in Kazakhstan, such areas are being reduced (Table 1). Over the last 5 years, the area under cultivation for organic products has decreased by a quarter (from 303 thousand hectares to 113.4 thousand hectares). However, the application of organic fertilizers amounted to 1.2 million tons, which was twice as much as in 2016 [26].
Of the total sown area in 2021, oilseed crops were sown on 3.09 million hectares. Shares of maize and soybean accounted for 9.76% of all oilseed crops. The areas sown with maize and soybean increased, amounting to 188.70 and 112.97 thousand hectares, respectively, in 2021. As shown in Table 2, when areas sown with maize had a growth trend, soybean had a downward trend. However, the yields of maize and soybean increased from year to year, which is a sign of the agricultural cultivation of the area, amounting to 5.98 and 2.10 tons/ha, respectively. Maize production increased by 67.5% over 5 years and amounted to 1.13 million tons in 2021 [12].
2.2. Site Description and Experimental Design
Field experiments were carried out at the Baltabay-2030 experimental farm, Baltabay village, Enbekshikazakh District, Almaty Region (latitude 43°30′23.256″, longitude NE 77°32′38.76″). The experiments were aimed at determining the effects of commercial organic fertilizers on the quality and yield of maize and soybean seed. The experimental plot was located 600 m above sea level. The treatment area had gray soil with a pH of 8.0. The total humus in the experimental area was 1.34%, and the NPK concentrations in the soil were 2.8, 35.2, and 240.2 mg/kg, respectively (Table 3). The experimental plot, with an area of 700 m2, was divided into 2 sections for planting maize and soybean to which various fertilizers were applied. In the experiment, an SPC-6 precision seeder was used (using the belt sowing method with row spacings of 50 × 20 cm). The soybean cultivar was the local Birlik KV. The seeding rate for soybean was 600 thousand viable seeds/ha, and the sowing depth was 4–6 cm. The maize hybrid was P1241 (FAO 670) in this experiment. The sowing pattern was standard sowing with one line for maize, with a distance between the rows of 70 cm and a sowing depth of 5–6 cm, and the seed rate was 70–75 thousand/ha. In this study, fertilization was based on a control and 6 variations, as shown in Table 4.
2.3. Determination of Fertilizer NPK and Efficiency
The nitrogen content was determined by titration using the Kjeldahl method. This method involves digesting the sample with concentrated sulfuric acid, with hydrogen peroxide as an oxidant and potassium sulfate to increase the boiling point of the sulfuric acid. After sample mineralization, nitrogen occurs in the form of ammonium sulfate [27].
The phosphorus content was determined using a Cary 60 UV spectrophotometer (Agilent Technologies, Penang, Malaysia). A range of phosphorus solutions (0–500 mg/L) was prepared by dissolving potassium dihydrogen phosphate (KH2PO4). Spectrophotometric methods for determining elements use the absorption of visible radiation and are among the most precise methods of analysis. The spectrophotometric wavelength was 882 nm, and the analysis was conducted after a blue color was developed using molybdenum blue [28].
The potassium content was determined using a Shimadzu AA-7000 flame atomic absorption spectrometer (Shimadzu, Tokyo, Japan) equipped with a hollow cathode lamp (Hamamatsu Photonics K.K., Hamamatsu, Japan) and an acetylene flame. The potassium wavelength used was 766.49 nm. The air–acetylene flow was 50 dm3/h, and the aspiration degree was 5 cm3/min. The calibration curves were prepared using a potassium (K) (Ecroskhim Co., Ltd., Moscow, Russia) standard solution (1000 mg/L). A calibration solution was prepared between 1 and 10 mg/L. Ultrapure water obtained from a Milli-Q system (Merck Millipore, Burlington, MA, USA) was used to prepare the solutions. All chemical reagents were of analytical grade, including nitric acid (Sigma-Aldrich, St. Louis, MO, USA) and hydrogen peroxide (Sigma-Aldrich, St. Louis, MO, USA). In the next step, 1 g of homogenized dried sample was placed in a 50 mL quartz crucible; the sample was placed in a cool muffle furnace, and the temperature was increased to 500–550 °C for a few hours. Then, the ash was dissolved in 50 mL of a 1% nitric acid solution and homogenized. After, the prepared solvent was diluted to 25 mL in a volumetric flask [29].
Agronomic efficiency (AE), which is a measure of yield per unit fertilizer applied for each treatment, was calculated using the yield from each treatment. Agronomic efficiency was calculated using following equation:
where AE—agronomy efficiency, kg yield/kg NP; YF—maize and soybean yield from each treatment, kg/ha; Yc—maize and soybean yield from the control plot, kg/ha; NP—applied fertilizer, kg/ha.
AE = YF – Yc/NP applied (kg NP/ha)
2.4. Determination of Quality Parameters of Maize and Soybean
The analysis of maize and soybean quality after harvesting was based on the determination of seed moisture, fat, protein, starch, and fiber. The fat content was determined using a Soxhlet apparatus and involved the repeated continuous extraction of a fatty phase from the crushed, dried seed, the use of an n-hexan that was removed, and the determination of a fatty substance using the weight method [30]. Protein was measured using the Kjeldahl method after sample digestion with concentrated H2SO4 and H2O2. The protein content was calculated by converting the crop nitrogen into a protein percentage by multiplying it by a factor of 5.95 [31]. Moisture was determined after drying the samples in a furnace (SNOL 6.7/1300, Utena, Lithuania) at 130 °C for 16 h. The samples were cooled in a desiccator with calcium chloride at the bottom. The moisture percentage was calculated from the mass lost after drying [32]. The seed starch content was measured via infrared reflectance spectroscopy using an InfraLUM FT-12 analyzer (Lumex, Saint Petersburg, Russia) [33]. Fiber content was determined by digesting the sample with 1.25% H2SO4 and 1.25% NaOH [34].
2.5. Sample Preparation for Fatty Acid Determination
For this process, 2.75 g of sodium methylate powder (Sigma Aldrich, St. Louis, MO, USA) was dissolved with 25 mL of methanol (Sigma Aldrich, St. Louis, MO, USA) in a 25 mL volumetric flask. The solution was vortexed and cooled at room temperature. Then, 0.10 ± 0.01 mL of maize and soybean oil was weighed in a 15 mL tube, and 2 mL of n-hexane was added. Then, 0.1 mL of the sodium methylate mixture was added and vortexed for 1 min. After the methylation reaction, the mixture settled for 5 min and was then centrifuged at 3000 rpm for 10 min. Finally, 1 mL of supernatant was transferred to a vial and used for GC injection [35].
2.6. Fatty Acid Methyl Ester (FAME) Preparation and GC/MS Analysis
The FAME content was determined using a Trace 1310 GC equipped with a TSQ 8000 Evo mass spectrometer and an AI 1310 autosampler (Thermo Scientific, Austin, TX, USA), using a TR-FAME silica column (60 m × 0.25 mm × 0.25 µm, Thermo Fischer Scientific, Bellefonte, PA, USA). The carrier gas was 99% pure helium, and the device was equipped with a triple helium gas filter (Thermo, Singapore) and operated at a flow rate of 1.0 mL/min. The chromatography parameters for FA determination were as follows: injector temperature, 230 °C; MS transfer line temperature, 250 °C; ion source temperature, 240 °C, ionization mode, EI; scan, 30–550 m/z; split flow, 15.0 mL/min; and split mode, 1:40. The initial temperature program of the column started at 110 °C, increased by 4 °C/min to 210 °C and was maintained for 8 min, and then increased by 2 °C/min to 250 °C and was maintained for 7 min. The total analysis time was 60 min. The injection volume was 1.0 µL. FAME standards (a FAME mix with 37 FA components; Supelco, Merck, Darmstadt, Germany) were determined using FAMEs; then, the identified compounds were determined via a peak area normalization (summing all peaks and then finding the percentage of each compound) [36].
2.7. Validation of GC/MS Analysis
The FA analysis using GC/MS was validated according to the ICH Guidelines [37]. The method was validated for linearity and the ranges of the fatty acid calibration curves. Linearity was validated using the 37 FAME mix standard. The identification of FAME components was carried out using the retention time and a chromatogram with the standard FAME mix certificate. GC conditions, including the column temperature, flow rate, and split ratio, were improved to acquire good FA separation. The precision of the method was validated by repeating the procedure with a standard mix solution 5 times. Chromatographic system accuracy was confirmed by testing %RSD retention.
2.8. Statistical Analysis
Quality parameters and FA contents were submitted to a hierarchical clustering analysis (HCA) which was performed using Euclidean distance. FA and quality parameter mean values were related using a principal component analysis (PCA). Pearson’s correlation coefficient was used to examine the relationships among variables. The values of each FA and quality and yield parameters were matched using an analysis of variance (ANOVA)., Tukey’s test was performed to identify significantly different mean values (p < 0.05). Statistical analyses were performed using JMP (JMP Statistical Discovery LLC, Cary, NC, USA) and Statistica 7 (StatSoft TIBCO Sofware Inc., Palo Alto, CA, USA).
3. Results and Discussion
3.1. Fertilizer Application
The NPK contents of fertilizers are shown in Table 5. Different organic fertilizer inputs caused significant differences in the quantity parameter of NPK (p < 0.05). According to the results, the most N was found in the HansePlant fertilizer; in the Prairie Pride B complex, the N content was 10.11% and in Smart Start, it was 3.81%. In the Tumat fertilizer, which is based on brown coal which contains humic acid, the N content was 2.11%. The Agroflorin enzyme complex fertilizer had 2.72%. The manure and Biohumus fertilizers had the lowest values, 0.52% and 0.28%, respectively. A high P content was found in the HansePlant fertilizer complex, with 33.23% in Smart Start P and 40.21% in Prairie Pride B. The P contents in Agroflorin and Tumat were 16.14% and 7.64%, respectively. The percentage of P was less than 3% in the other treatments. The high K content in most treatments varied between 3.43% and 8.78%. The Biohumus vermicompost fertilizer had the highest percentage, 8.78%, while Bioecohum vermicompost fertilizer had 5.23%. The Tumat manure and humus fertilizers had 0.64% and 0.74%, respectively. Humic acid from coal can be successfully used to improve soil characteristics and increase yield [38,39]. Few research studies have reported the effects of manure fertilizer on the parameters of maize and soybean [40,41]. In recent years, enzyme complexes prepared via microbial processes have shown good results in production and could be used to treat soils to improve grain yield and quality parameters [42].
3.2. Effects of Different Fertilizers on Maize and Soybean Quality
Table 6 shows the effects of different types of fertilizers on maize and soybean quality parameters, including moisture, fat, protein, fiber, and starch. Among the given indicators, the difference in moisture content in maize remained the same as in the control and HansePlant treatments at 72.15% and 71.88%, respectively, while in the other treatments, it was higher than 80%. The poor performance with the HansePlant treatment may have been due to the influence of nitrogen treatment, which can reduce seed moisture content (Table 6). The moisture percentage in soybean was approximately the same (12.43–13.09%). It can be observed that the higher the treatment level, the higher the moisture content. A similar phenomenon occurs with fertilizer and fat level in maize and soybean. Fat and protein values with all applied fertilizers were higher than those of the control sample, which means the nutrients have nutritional value. This was confirmed by Księżak et al., who found an increasing effect on protein content in soybean, which was significantly increased by about 14% compared to non-fertilized soybean [43]. Efthimiadou et al. reported the same fat and protein results after applying various concentrations of N fertilizer treatments, with the protein content varying between 6.39% and 6.71% and fat between 2.93% and 3.0% [44]. The fat levels in maize with fertilizer applied were significantly different, ranging from 3.86% to 4.61% (control 3.42%), and in soybean, they ranged from 19.22% to 22.85% (control 19.09%). In maize, Agroflorin treatment resulted in the lowest fiber content (3.68%) and the highest starch content (78.81%), which may have been due to the high phosphorus content in the fertilizer. Our results agree with those of the authors of [45], who reported that the P content was increased in maize. The starch content varied significantly between treatments. The application of all types of fertilizers had a positive effect on the starch content of maize, which varied from 73.77% to 78.87% compared to the control (73.2%). The HansePlant, Agroflorin, and Bioecohum treatments resulted in significantly elevated starch contents compared with control maize samples, with values of 3.97%, 5.61%, and 5.67%, respectively. Previous research reported that N fertilizer application substantially increased maize starch [46].
3.3. Effects of Different Fertilizers on Yield of Maize and Soybean
The positive influence of fertilizers made it possible to ensure maize yields averaging 12.38–15.36 t/ha, as shown in Table 7. The highest yield was obtained with the Bioecohum treatment (15.36 t/ha), then Agroflorin (14.20 t/ha), and slightly lower yields were obtained with HansePlant and manure (14.06 and 13.92 t/ha, respectively). The yields with the Biohumus and Tumat treatments were 12.72 and 12.38 t/ha, respectively, while that of the control variant was 10.48 t/ha. The maize grain yield in all treatments increased in the order Bioecohum > Agroflorin > HansePlant > manure > Biohumus > Tumat, with increments of 47%, 35%, 34%, 33%, 21%, and 18%, respectively, over the control. The maize yields for all treatments were significantly higher than the control (p < 0.05), and the combined effects of fertilizers may be the cause. Using the Bioecohum, Agroflorin, and HansePlant fertilizers with high NPK (Table 5) significantly increased the maize yield compared to the control (p < 0.05). These results agree with previous research, which showed a positive impact of organic fertilizer treatments on yield [27,47,48]. Glaser et al. [49] reported a maize yield of 8 t/ha in an experimental plot treated with mineral fertilizer and compost. Guo et al. showed that maize grain yield was significantly different with vermicompost than traditional manure, with yield increasing by 18.3% [50]. Gao et al. reported maize yields with chemical, biofertilizer, and organic fertilizer treatments. The combination of humic acid and biofertilizer led to improved growth and yield and resulted in maize roots absorbing more NPK nutrient contents from the soil, which increased growth and yield [51].
The results of this research show that the highest soybean yield was achieved with HansePlant, at 4.96 t/ha, which was 1.53 t/ha higher than the control without fertilizer (3.43 t/ha) (Table 7). The yields with the Bioecohum and Tumat treatments were 4.71 and 4.62 t/ha, respectively, and manure and Agroflorin showed similar results of 4.34 and 4.31 t/ha, respectively. Soybean yield with all treatments increased in the order HansePlant > Bioecohum > Tumat > manure > Agroflorin > Biohumus, with increments of 31%, 27%, 26%, 21%, 20%, and 19%, respectively, over the control. Our results are similar to those in [52], which reported a higher maize yield with the application of organic and inorganic fertilizers. Lin et al. reported that the efficiency of organic N fertilizer was lower than that of chemical N fertilizer; organic fertilizer nutrients are absorbed by crops over a long period [13].
3.4. Validation of Method by GC/MS for Fatty Acids
The method for determining FAs was validated using a 37 FAME mix calibration standard. Identification of all FA components was performed using a chromatogram and retention times on the standard mix certificate, as shown in Table 8 and Figure 1. Retention times and calibration curves are also shown in Supplementary Figure S1.
FA values were quantitatively analyzed, and calibration curves were plotted between 5 and 612 ng/mL. The calibration curves included five concentrations (Figure S1). Each FA component is shown in Table 6 with its retention time, linearity range equation, correlation coefficient, limit of detection (LOD), and limit of quantification (LOQ). A correlation coefficient of more than 96% confirmed the excellent detector response.
The FAME mix standard analysis was replicated to determine the method’s accuracy and precision. The repeatability for standards for retention times, calculated as %RSD, was not greater than 0.5%. The calculation for peak areas was not greater than 1.0%, the calculation for the same conditions for the precision of the retention time was not bigger than 0.3%, and for peak areas, it was not greater than 1.0%. The LOD varied between 0.10 and 0.38 ng/mL, and the LOQ was between 0.36 and 1.15 ng/mL, which shows that the method is sensitive. The above data indicate that this method is suitable for identifying FAs in vegetable oil products and is in compliance with ICH guidelines [37].
3.5. Determination of Fatty Acids in Vegetable Oils
The FA profiles of maize and soybean grains were determined (Table 9 and Table 10). All oil FA composition analyses were methylated and duplicated on the same day, and all samples were analyzed only on a TR-FAME capillary column (60 m × 0.25 mm × 0.25 µm). The use of a 60 m high-polarity capillary column resulted in good separation of numerous FAs, as well as cis- and trans-isomers [53].
The fatty acid composition of an oil determines its nutritional and industrial value and can impact its commercial value. Fertilizer treatments had a significant effect on C16:0 palmitic, C18:0 stearic, C18:1n9c oleic, C18:2n6c linoleic, and C18:3n3c α-linolenic acids. As shown in Table 9, five FAs presented as the main FAs of maize oil. The content of saturated C16:0 palmitic acid in the control sample (15.12%) was higher than that in the samples from other treatments except Tumat (15.85%). Monounsaturated C18:1n9c oleic acid was the highest with the manure treatment (33.89%), with a lower percentage of polyunsaturated C18:2n6c linoleic acid (46.21%) than the other fertilizer treatments. Oleic acid is considered one of the most important USFAs in maize; it has an important role in human nutrition and is highly resistant to oxidation [54]. The polyunsaturated C18:2n6c linoleic acid content ranged from 46.21% to 50.95%. Linoleic acid is one of the most important unsaturated fatty acids in maize, playing an important role in nutrition [55]. Although the C18:2n6c content was not significantly different among treatments, the values of samples from the Bioecohum and Biohumus treatments were higher than those from other treatments. This may be because these treatments have higher percentages of K, 5.23% and 8.78%, respectively. C18:3n3c α-linolenic acid was increased with all treatments, especially HansePlant (2.21%) and Agroflorin (1.04%), compared to the control. The results show that the percentage of stearic acid was not affected by fertilizer interactions. Generally, all analyzed samples were characterized by a high percentage of USFAs (81.20–83.10%) and a low percentage of SFAs (16.91–19.61%), which are beneficial for human health [56,57]. Omega-6 and omega-3 PUFAs are important as they have beneficial nutritional value and, according to recommendations, the omega-6/omega-3 ratio should be in the range of 15/1 to 16.7/1. Modern agricultural practices have led to decreases in omega-3 and increases in omega-6 [58]. According to the FAO/WHO, the recommended omega-6/omega-3 ratio is 5–10:1 [59]. According to our study, the use of HansePlant (22.40) resulted in the lowest omega-6/omega-3 ratio, Agroflorin resulted in a ratio of 46.36, and Bioecohum resulted in a ratio of 69.45, whereas the ratio for the control was 167.10.
Various fertilizer treatments had a significant effect on C16:0 palmitic, C18:0 stearic, C18:1n9c oleic, C18:2n6c linoleic, and C18:3n3c α-linolenic acids in soybean. As shown in Table 10, the content of saturated C16:0 palmitic acid in control samples (15.12%) was higher than that in samples from other treatments except Tumat (15.85%). C16:0 palmitic and C18:0 oleic acids increased slightly with Bioecohum, which affected the K application rate. Other authors have reported increased oleic acid in soybean with K fertilizers [60]. The highest percentage of polyunsaturated C18:2n6c linoleic acid was obtained with manure treatment (40.61%), and the lowest percentage was obtained with Bioecohum. Researchers reported that in experiments on soybean, N treatment reduced the content of palmitic acid [61,62]; this is similar to our results, with high percentages of palmitic acid with the HansePlant (13.64%), Agroflorin (13.34%), Biohumus (14.01%), and Tumat (13.51%) treatments compared to the control (14.77%). The polyunsaturated C18:2n6c linoleic acid content ranged from 46.21% to 50.95%. Although the C18:2n6c content was not significantly different among treatments, the values with the Bioecohum and Biohumus treatments were higher than those with the other treatments. This may be because these treatments have higher percentages of K, 5.23% and 8.78%, respectively [63]. The PUFA/SFA ratio is associated with an impact on coronary heart disease. Thus, a higher PUFA/SFA ratio means a more positive health effect [64]. In our research, we used the commonly used PUFA/SFA ratio for evaluating the nutritional value of soybean and maize and the influence of various types of fertilizers on this ratio. The highest ratios were obtained with the manure, HansePlant, and Agroflorin treatments (2.49, 2.41, and 2.40, respectively). In this research, the lowest omega-6/omega-3 lowest ratios were determined for the Bioecohum (3.26), Biohum (3.48), Agroflorin (3.67), and HansePlant (3.73) treatments, whereas the ratio was 4.44 for the control. The P and K fertilizer treatments showed the lowest omega-6/omega-3 ratios.
3.6. Principal Component Analysis
In this research, a multidimensional statistical analysis was carried out using a PCA for the influence of various fertilizers on maize and soybean quality and FA components with the dependent variables being fertilizer treatments. The main components were the fertilizer treatments. As shown in Figure 2a, a PCA of maize was responsible for explaining 64.91% of the total variance, with PC1 accounting for 38.61% and PC2 accounting for 26.30%. Six fertilizer treatments were grouped in a distinct group, as shown by the PCA plot in Figure 2a, and each group could be distinguished; the control, Agroflorin, Bioecohum, and HansePlant treatments were close together due to their similar dependent variables, unsaturated C18:26c, C18:3n6c, and C18:3n3c, and starch. Another group comprised Tumat and manure treatments, which were mainly related to the SFAs C16:0 and C18:0 and the monounsaturated acids C18:1n9c and C20:1n9c, as well as moisture parameters. The third group consisted only of Biohumus, with the main quality parameters of protein, fat, and fiber.
As shown Figure 2b, the PCA of soybean was responsible for explaining 58.98% of the total variation, with PC1 accounting for 37.07% and PC2 accounting for 21.91%. Six fertilizers were separated into groups by FA content and quality parameters. The control was mainly related to C18:1n9c and starch. The Tumat and Biohumus treatments were similar in terms of moisture and the MUFA C20:1n9c. The Bioecohum treatment was related to the SFAs C16:0 and C18:0 and the PUFA C18:3n6c. The third group consisted of manure, grouped based on high levels of fat, protein, and fiber. HansePlant and Agroflorin were mainly related by the USFAs C18:2n6c, C18:3n3c, and C20:1n9c. In this research, a PCA used to discriminate fertilizer treatments by FA content and quality parameters, whereas other authors [40,65,66] used PCAs to reveal the factors of FA composition and the quality of various types of fertilizers.
3.7. Cluster Analysis
The relationship between fertilizer treatments and quality and yield parameters was determined through a hierarchical clustering analysis using Ward’s linkage. The obtained dendrogram classified the maize treatments into two groups (Figure 3a). The first group consisted of control, manure, Tumat, and Biohumus and was characterized by the same content of omega-3 (0.30–0.38%) and similar omega-6/omega-3 ratios, ranging from 121.61 to 167.10, as shown in Table 9. As shown in Table 11, the treatments in the first maize group had a strong connection with each other, with Euclidean distances of 3.7–46.9. Especially, manure and Tumat were very similar, with an average distance of 3.7. The second group consisted of HansePlant, Agroflorin, and Bioecohum treatments, with higher amounts of NPK than the other treatments, as shown in Table 5. As shown in Table 7, the second group was characterized by higher omega-3 values (0.73–2.21%) and lower omega-6/omega-3 ratios (22.4–69.45) than the first maize group. The second group was also a high-yielding group, with an average yield of 14.06–15.36 t/ha (Table 7). HansePlant was more distinct, with a Euclidean distance of 100 to 145 from the first group but closer to Agroflorin (26) and Bioecohum (48) in the second group.
Figure 3b shows a dendrogram of soybean treatments. According to the obtained results, soybean treatments were divided into two groups. The dendrogram clearly shows that the first group, the control, was located separately, with a Euclidean distance of 4.93–8.00 from other treatments (Table 12). The second soybean group, including all treatments, was characterized by quality parameters, mainly fat and protein, and fiber. Also, there were significant differences in yield parameters (Table 7). As shown in Table 10, there were high omega-3 and PUFA/SFA ratios and a lower omega-6/omega-3 ratio than the control. In our research, a cluster analysis was employed to investigate the impact of fertilizer treatments on clustering variation and other data processing parameters, including FAs, quality, and yield [67,68].
3.8. Correlation Analysis
The Pearson correlation coefficients between maize’s main FA parameters and the quality parameters are shown in Table 13. Our results indicate a weak correlation between the main FA ratios and quality in maize. The total study correlation analysis of the main fatty acid ratios demonstrated significantly positive correlations between PUFAs and omega-6 (r = 0.96), PUFAs and PUFA/SFA (r = 0.92), and omega-6 and PUFA/SFA (r = 0.92) (Table 13). The starch parameter demonstrated a significant negative correlation with protein (r = −0.94) and SFAs and PUFA/SFA (r = −0.95). The ratio of omega-6 to omega-3 had a significant negative correlation with omega-3. (r = −0.87).
Our results show that the total study correlation analysis of the main fatty acid ratios demonstrated significant positive correlations between SFAs and MUFAs (r = 0.85) and omega-6 and PUFA/SFA (r = 0.85) (Table 14). The PUFA/SFA ratio demonstrated a significant negative correlation with SFAs (r = −0.93) and MUFAs (r = −0.91). The ratio of omega-6 to omega-3 had a significant negative correlation with omega-3 (r = −0.95), and moisture had a significant negative correlation with fiber (r = −0.80). There were important interactions between fertilizers and quality and FA parameters. Fertilizer treatments can have a direct or indirect influence on grain productivity [40,69].
4. Conclusions
This paper presents an analysis of the influence of commercial organic fertilizers on changes in quality, yield, and FA parameters in maize and soybean. Treatments with various organic fertilizers resulted in maize and soybean absorbing more essential nutrients, which increased grain quality parameters, such as fat, protein, starch, and fiber contents. When the recommended quantity of commercial organic fertilizers was applied, maize and soybean growth and yield were improved. Biologically active compounds of organic fertilizers improved the quality parameters fat, protein, fiber, and starch in maize by 35%, 22%, 14%, and 8%, respectively, over a control, as well as fat, protein, and fiber in soybean by 20%, 3%, and 11%, respectively. Organic fertilizers with high NPK affected the harvest, increasing yield in maize by 47% and in soybean by 31%. The results indicate a strong relationship between fertilizer treatments and the omega-6/omega-3 ratio. FA contents showed that the treatments influenced to decrease the omega-6/omega-3 ratio from 167.10 (control) to 22.40 (HansePlant) in maize; a lower ratio is recommended by the FAO/WHO. The same omega-6/omega-3 ratio results were demonstrated in soybean, in which the ratio varied from 4.44 (control) to 3.26 (Bioecohum).
Supplementary Materials
The following supporting information can be downloaded at https://www.mdpi.com/article/10.3390/su16010162/s1. Figure S1. Acid retention time and calibration curve of each FAME 37 standard mix component by GC/MS. Figure S2. GC chromatogram of maize (red line) and soybean (blue line) control samples. Analyzed on TR-FAME capillary column (60 m × 0.250 mm × 0.25 µm). Column temperature was programmed as follows: 1100 °C at 40 °C/min, 2100 °C (8 min) at 20 °C/min, and 2600 °C (7 min).
Author Contributions
Conceptualization, M.T. and A.S. (Assiya Serikbayeva); methodology, M.T. and A.S. (Aksholpan Shokan); formal analysis, M.T., A.S. (Aksholpan Shokan) and N.M.; investigation, M.T., Z.S. and Z.D.; data curation, M.T., S.K. and G.Y.; writing—original draft preparation, M.T., Z.S. and S.K.; writing—review and editing, M.T., A.S. (Assiya Serikbayeva) and Z.D.; visualization, M.T.; supervision, A.S. (Assiya Serikbayeva); project administration, A.S. (Assiya Serikbayeva); funding acquisition, A.S. (Assiya Serikbayeva). All authors have read and agreed to the published version of the manuscript.
Funding
The Ministry of Agriculture of the Republic of Kazakhstan funded this research through a project titled “The development of techniques for processing agricultural raw materials that comply with Halal standards” and through the scientific and technical program, BR10764970, through a project titled “The development of science-intensive technologies for the deep processing of agricultural raw materials increase the range and yield of finished products from unit of raw materials” in 2021–2023.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
Data are contained within the article and Supplementary Materials.
Conflicts of Interest
The authors declare no conflict of interest.
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Figure 1.
GC chromatogram of 37 FAME mix standard. Analyzed on TR-FAME capillary column (60 m × 0.250 mm × 0.25 µm). Column temperature was programmed as follows: 110 °C at 4 °C/min, 210 °C (8 min) at 2 °C/min, and 260 °C (7 min).
Figure 1.
GC chromatogram of 37 FAME mix standard. Analyzed on TR-FAME capillary column (60 m × 0.250 mm × 0.25 µm). Column temperature was programmed as follows: 110 °C at 4 °C/min, 210 °C (8 min) at 2 °C/min, and 260 °C (7 min).
Figure 2.
Principal component analysis of FA composition. PCA loading plot for (a) maize; (b) soybean.
Figure 2.
Principal component analysis of FA composition. PCA loading plot for (a) maize; (b) soybean.
Figure 3.
Dendrograms of clustering analyses of (a) maize and (b) soybean based on each oil’s FA composition and quality parameters after fertilizer treatment. Horizontal distance shows Euclidean distance.
Figure 3.
Dendrograms of clustering analyses of (a) maize and (b) soybean based on each oil’s FA composition and quality parameters after fertilizer treatment. Horizontal distance shows Euclidean distance.
Table 1.
Application of mineral and organic fertilizers in Kazakhstan.
| Parameter | Unit | Year | |||||
|---|---|---|---|---|---|---|---|
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | ||
| Consumption of mineral fertilizers | |||||||
| Area of agricultural land (sown area of agricultural crops) | Million ha | 21.5 | 21.8 | 21.9 | 22.1 | 22.6 | 22.9 |
| Nitrogen (N) fertilizer use | Thousand tons | 80 | 104.2 | 81.2 | 54.5 | 74.4 | 81 |
| kg/ha | 3.7 | 4.8 | 3.7 | 2.5 | 3.3 | 3.5 | |
| Phosphate (P2O5) fertilizer use | Thousand tons | 31.5 | 50.3 | 38.3 | 29.4 | 88.1 | 47.7 |
| kg/ha | 1.5 | 2.3 | 1.7 | 1.3 | 3.9 | 2.1 | |
| Potash (K2O) fertilizer use | Thousand tons | 2.3 | 3.7 | 1.2 | 1.7 | 2.3 | 3.2 |
| kg/ha | 0.1 | 0.2 | 0.1 | 0.1 | 0.1 | 0.1 | |
| Total volume of applied mineral fertilizers | Thousand tons | 113.8 | 158.2 | 120.9 | 86.5 | 165.5 | 132.9 |
| Volume of mineral fertilizer use per unit area | kg/ha | 5.3 | 7.3 | 5.5 | 3.9 | 7.3 | 5.8 |
| Area treated with mineral fertilizers | Million ha | 1.65 | 2.51 | 2.34 | 2.66 | 3.05 | 3.8 |
| Share of area treated with mineral fertilizers in total area of agricultural land | % | 7.7 | 11.5 | 10.7 | 12.0 | 13.5 | 16.6 |
| Use of organic fertilizers | |||||||
| Area under organic agriculture | Thousand ha | 303.4 | 277.1 | 192.1 | 294.3 | 114.89 | 113.24 |
| Application of organic fertilizers | Thousand tons | 626.6 | 896 | 633.0 | 619.5 | 1214.1 | 995.2 |
| Use of organic fertilizers per unit area | kg/ha | 29.1 | 41.1 | 28.9 | 28.0 | 53.7 | 43.5 |
| Area treated with organic fertilizers | Million ha | 0.08 | 0.12 | 0.10 | 0.1 | 0.1 | 0.1 |
| Share of area treated with organic fertilizers in total area of agricultural land | % | 0.38 | 0.53 | 0.46 | 0.43 | 0.44 | 0.44 |
Table 2.
Maize and soybean production and yield parameters in Kazakhstan.
| Parameter | Unit | Year | ||||||
|---|---|---|---|---|---|---|---|---|
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | |||
| Maize | Production | Thousand tonnes | 762.36 | 784.69 | 862.09 | 895.98 | 958.11 | 1129.51 |
| Area harvested | Thousand ha | 135.11 | 136.67 | 150.06 | 156.28 | 162.81 | 188.70 | |
| Yield | ton/ha | 5.64 | 5.74 | 5.74 | 5.73 | 5.88 | 5.98 | |
| Soybean | Production | Thousand tonnes | 231.17 | 252.32 | 255.44 | 282.18 | 260.64 | 237.85 |
| Area harvested | ha | 106.09 | 125.49 | 123.62 | 138.84 | 125.07 | 112.97 | |
| Yield | ton/ha | 2.17 | 2.01 | 2.06 | 2.03 | 2.08 | 2.10 | |
Table 3.
The experimental site’s soil characteristics.
| Soil Characteristics | Value |
|---|---|
| Texture | Loam |
| pH | 8.0 |
| Humus (%) | 1.34 |
| N (mg/kg) | 2.8 |
| P (mg/kg) | 35.2 |
| K (mg/kg) | 240.2 |
| S (mg/kg) | 3.4 |
| Zn (mg/kg) | 38.89 |
| Fe (mg/kg) | 51.5 |
| Mn (mg/kg) | 18.4 |
| Ni (mg/kg) | 0.70 |
| Co (mg/kg) | 0.77 |
Table 4.
Fertilizer treatments on maize and soybean in the experimental field.
| # | Fertilizer | Description | Treatment |
|---|---|---|---|
| 1 | Control | No fertilizer | - |
| 2 | Manure | Rotted dairy manure | 30 ton/ha |
| 3 | Biohumus | Biologically active organic fertilizer produced via an original biotechnology, vermiculture, a product of manure processing by the Californian red worm | 2 ton/ha |
| 4 | HansePlant | Complex nutrition consisting of balanced concentrated nitrogen–phosphorus–potassium fertilizers:
| SeedSpor S 2.0 mL/kg seed: seed treatment before sowing; Smart Start P 150 kg/ha: application of starter fertilizer at sowing; HanseBiosulfur 5.0 L/ha: first foliar application in 2-to-4-leaf phase; Prairie Pride A 3.0 L/ha + Prairie Pride B 7.5 kg/ha + Absorb 1.0 L/ha: second foliar application in 6-leaf phase |
| 5 | Bioecohum | Dark brown liquid suspension obtained from vermicompost processed by compost worms in special nurseries with various organic, raw materials via enrichment with nutrients in a form accessible to plants. | 0.25 L/100 kg: seed treatment before sowing; 5.0 L/ha: first foliar application in 2-to-4-leaf phase; 5.0 L/ha: second foliar application in 6-leaf phase |
| 6 | Tumat | Organic humic fertilizer produced from brown coal (leonardite and lignite) and specially prepared water; contains humic acids, fulvic acids, amino acids, organic salts, organic acids, natural auxins, and cytokinins. | 30 mL/100 kg: seed treatment before sowing; 1.0 L/ha: first foliar application in 2-to-4-leaf phase; 1.0 L/ha: second foliar application in 6-leaf phase |
| 7 | Agroflorin | Enzyme complex preparation used for increasing soil productivity and fertility or for emergency treatment in case of signs of plant disease and stress factors. | 0.25 L/ha: first foliar application in 2-to-4-leaf phase; 0.25 L/ha: second foliar application in 6-leaf phase |
Table 5.
Fertilizer application amounts for all treatments.
| # | Fertilizer | N (%) | P2O5 (%) | K2O (%) |
|---|---|---|---|---|
| 1 | Control | - | - | - |
| 2 | Manure | 0.52 ± 0.01 | 0.23 ± 0.01 | 0.64 ± 0.01 |
| 3 | Biohumus | 0.28 ± 0.01 | 0.75 ± 0.01 | 8.78 ± 0.02 |
| 4 | HansePlant | 3.81 ± 0.08 * | 33.23 ± 0.25 * | 0.14 ± 0.01 * |
| 1.12 ± 0.09 ** | 3.14 ± 0.08 ** | 3.43 ± 0.04 ** | ||
| 10.11 ± 0.12 *** | 40.21 ± 0.75 *** | 6.13 ± 0.09 *** | ||
| 5 | Bioecohum | 1.05 ± 0.8 | 1.10 ± 0.02 | 5.23 ± 0.09 |
| 6 | Tumat | 2.11 ± 0.08 | 7.64 ± 0.03 | 0.74 ± 0.08 |
| 7 | Agroflorin | 2.72 ± 0.07 | 16.14 ± 0.08 | 5.45 ± 0.05 |
* Smart Start P; ** Prairie Pride A; *** Prairie Pride B.
Table 6.
Main quality indicators after fertilizer treatments.
| Quality Parameter | Crop | Fertilizer | ||||||
|---|---|---|---|---|---|---|---|---|
| Control | HansePlant | Manure | Agroflorin | Bioecohum | Biohumus | Tumat | ||
| Moisture (%) | Maize | 72.15 ± 1.35 | 71.88 ± 1.55 | 80.51 ± 1.10 | 81.48 ± 1.28 | 82.04 ± 1.25 | 80.45 ± 1.11 | 82.32 ± 1.41 |
| Soybean | 12.77 ± 0.02 | 12.83 ± 0.02 | 12.43 ± 0.03 | 12.71 ± 0.01 | 12.69 ± 0.03 | 12.97 ± 0.09 | 13.09 ± 0.08 | |
| Fat (%) | Maize | 3.42 ± 0.07 | 4.16 ± 0.05 | 4.06 ± 0.06 | 3.86 ± 0.09 | 3.90 ± 0.05 | 4.61 ± 0.00 | 4.07 ± 0.01 |
| Soybean | 19.09 ± 0.19 | 19.22 ± 0.23 | 22.85 ± 0.11 | 20.07 ± 0.85 | 19.49 ± 0.56 | 19.58 ± 0.63 | 19.87 ± 0.32 | |
| Protein (%) | Maize | 6.30 ± 0.01 | 6.86 ± 0.09 | 7.37 ± 0.01 | 6.42 ± 0.03 | 6.45 ± 0.03 | 7.66 ± 0.03 | 7.01 ± 0.04 |
| Soybean | 34.33 ± 0.25 | 35.23 ± 0.74 | 35.51 ± 0.54 | 35.05 ± 0.26 | 34.5 ± 0.28 | 34.65 ± 0.93 | 34.74 ± 0.36 | |
| Fiber (%) | Maize | 3.74 ± 0.03 | 3.98 ± 0.09 | 4.05 ± 0.04 | 3.68 ± 0.09 | 3.81 ± 0.06 | 4.28 ± 0.06 | 3.45 ± 0.09 |
| Soybean | 11.11 ± 0.15 | 11.18 ± 0.25 | 12.3 ± 0.58 | 11.9 ± 0.48 | 11.72 ± 0.99 | 11.24 ± 0.65 | 11.28 ± 0.63 | |
| Starch (%) | Maize | 73.2 ± 0.78 | 77.17 ± 1.72 | 73.77 ± 0.85 | 78.81 ± 2.24 | 78.87 ± 0.81 | 74.89 ± 0.82 | 75.74 ± 1.19 |
| Soybean | 1.29 ± 0.09 | 1.26 ± 0.02 | 1.24 ± 0.03 | 0.95 ± 0.03 | 1.03 ± 0.05 | 1.28 ± 0.04 | 1.19 ± 0.09 |
Table 7.
Influence of fertilizers on yield and agronomy efficiency after treatments.
| Treatment | Yield | Agronomy Efficiency | ||||
|---|---|---|---|---|---|---|
| Maize (t/ha) | Soybean (t/ha) | Maize | Soybean | |||
| N (kg Yield/kg N) | P2O5 (kg Yield/kg P) | N (kg Yield/kg N) | P2O5 (kg Yield/kg P) | |||
| Control | 10.48 ± 0.21 e | 3.43 ± 0.37 e | - | - | - | - |
| HansePlant | 14.06 ± 0.17 b | 4.96 ± 0.26 a | 1.30 | 2.81 | 0.56 | 1.20 |
| Manure | 13.92 ± 0.09 c | 4.34 ± 0.44 c | 0.02 | 0.05 | 0.01 | 0.01 |
| Agroflorin | 14.2 ± 0.22 b | 4.31 ± 0.12 c | 37.20 | 4.65 | 8.80 | 1.10 |
| Bioecohum | 15.36 ± 0.25 a | 4.71 ± 0.17 b | 32.53 | 44.36 | 8.53 | 11.64 |
| Biohumus | 12.72 ± 0.11 d | 4.21 ± 0.22 d | 0.40 | 1.49 | 0.14 | 0.52 |
| Tumat | 12.38 ± 0.38 d | 4.62 ± 0.19 b | 47.50 | 12.67 | 29.75 | 7.93 |
Mean ± SD. Letters represent significant differences between treatments at p < 0.05.
Table 8.
Results of LOD and LOQ values, retention times, and FA linearity parameter from calibration curve standard.
Table 8.
Results of LOD and LOQ values, retention times, and FA linearity parameter from calibration curve standard.
| # | Fatty Acid Component | RT (Mean) | R2 | Calibration Curve Equation | Range (ng/mL) | LOD (ng/mL) | LOQ (ng/mL) |
|---|---|---|---|---|---|---|---|
| 1 | C4:0 | 5.63 | 0.9929 | y = 3104.53 + 1283.98 ∗ x | 10.1–404 | 0.14 | 0.42 |
| 2 | C6:0 | 6.40 | 0.9761 | y = 4055.65 + 2253.24 ∗ x | 10.1–404 | 0.29 | 0.90 |
| 3 | C8:0 | 7.84 | 0.9968 | y = −4498.98 + 2166.69 ∗ x | 10.1–404 | 0.10 | 0.38 |
| 4 | C10:0 | 10.16 | 0.9943 | y = −7250.46 + 2412.19 ∗ x | 10.2–408 | 0.12 | 0.37 |
| 5 | C11:0 | 11.60 | 0.9972 | y = −8557.36 + 2688.21 ∗ x | 5.1–204 | 0.18 | 0.36 |
| 6 | C12:0 | 13.18 | 0.9715 | y = 9022.17 + 2778.84 ∗ x | 10.1–404 | 0.28 | 0.85 |
| 7 | C13:0 | 14.83 | 0.9822 | y = −20,977.31 + 2877.44 ∗ x | 5–203 | 0.22 | 0.67 |
| 8 | C14:0 | 16.52 | 0.9844 | y = −2093.06 + 2948.31 ∗ x | 10.1–404 | 0.20 | 0.62 |
| 9 | C14:1 | 17.45 | 0.9795 | y = −25,140.38 + 2986.51 ∗ x | 5.1–204 | 0.23 | 0.72 |
| 10 | C15:0 | 18.19 | 0.9855 | y = −22,493.77 + 3076.91 ∗ x | 5–203 | 0.20 | 0.61 |
| 11 | C15:1 | 19.13 | 0.9826 | y = −24,875.84 + 3126.89 ∗ x | 5–203 | 0.22 | 0.66 |
| 12 | C16:0 | 19.85 | 0.9604 | y = 10,724.23 + 1959.15 ∗ x | 15.3–612 | 0.37 | 1.13 |
| 13 | C16:1 | 20.56 | 0.9754 | y = −21,441.35 + 3363.23 ∗ x | 5.1–204 | 0.26 | 0.79 |
| 14 | C17:0 | 21.46 | 0.9834 | y = −25,294.81 + 3098.58 ∗ x | 5.2–210 | 0.21 | 0.65 |
| 15 | C17:1 | 22.17 | 0.9771 | y = −30,493.98 + 3341.48 ∗ x | 5.1–204 | 0.25 | 0.76 |
| 16 | C18:0 | 30.46 | 0.9805 | y = −48,181.39 + 3154.23 ∗ x | 10.2–408 | 0.23 | 0.70 |
| 17 | C18:1n9t | 23.37 | 0.9693 | y = 26,390.54 + 3563.75 ∗ x | 5–202 | 0.29 | 0.89 |
| 18 | C18:1n9c | 23.61 | 0.9804 | y = −58,757.32 + 3551.80 ∗ x | 10.1–404 | 0.23 | 0.70 |
| 19 | C18:2n6t | 24.03 | 0.9888 | y = −9356.52 + 3581.82 ∗ x | 5–202 | 0.17 | 0.53 |
| 20 | C18:2n6c | 24.60 | 0.9718 | y = −15,503.47 + 3639.81 ∗ x | 5–202 | 0.28 | 0.85 |
| 21 | C20:0 | 25.26 | 0.9809 | y = −28,503.12 + 1668.46 ∗ x | 10.2–408 | 0.21 | 0.69 |
| 22 | C18:3n6c | 25.81 | 0.9745 | y = 14,267.24 + 3307.24 ∗ x | 5–203 | 0.27 | 0.80 |
| 23 | C20:1n9c | 26.01 | 0.9618 | y = 8327.76 + 3712.91 ∗ x | 5–202 | 0.38 | 1.15 |
| 24 | C18:3n3c | 26.57 | 0.9769 | y = −58,364.16 + 6629.89 ∗ x | 5.1–204 | 0.25 | 0.77 |
| 25 | C21:0 | 27.68 | 0.9583 | y = −36,143.35 + 3030.50 ∗ x | 5–203 | 0.34 | 1.03 |
| 26 | C20:2 | 27.79 | 0.9774 | y = −32,230.17 + 3667.30 ∗ x | 5.1–204 | 0.25 | 0.76 |
| 27 | C22:0 | 28.58 | 0.9797 | y = −28,402.9 + 1657.1 ∗ x | 10.1–405 | 0.23 | 0.71 |
| 28 | C20:3 | 29.15 | 0.9630 | y = −7570.47 + 3334.73 ∗ x | 5.1–204 | 0.32 | 0.97 |
| 29 | C22:1 | 29.25 | 0.9649 | y = −9612.72 + 3435.02 ∗ x | 5.1–204 | 0.31 | 0.95 |
| 30 | C20:3 | 29.49 | 0.9846 | y = −41,006.87 + 5944.15 ∗ x | 5.1–204 | 0.21 | 0.62 |
| 31 | C23:0 | 30.28 | 0.9639 | y = 28,419.21 + 3093.43 ∗ x | 5–203 | 0.32 | 0.96 |
| 32 | C20:4 | 30.82 | 0.9636 | y = 28,013.89 + 3119.79 ∗ x | 5–202 | 0.32 | 0.97 |
| 33 | C22:2 | 31.53 | 0.9657 | y = 29,603.17 + 2804.69 ∗ x | 5.1–204 | 0.31 | 0.94 |
| 34 | C24:0 | 31.73 | 0.9924 | y = −21,241.08 + 1442.07 ∗ x | 5.1–204 | 0.14 | 0.43 |
| 35 | C20:5 | 33.91 | 0.9920 | y = 4049.98 + 4276.11 ∗ x | 5.1–204 | 0.15 | 0.45 |
| 36 | C24:1 | 34.90 | 0.9638 | y = 22,871.14 + 2312.33 ∗ x | 5.1–204 | 0.32 | 0.96 |
| 37 | C22:6 | 36.42 | 0.9845 | y = −1542.03 + 2480.62 ∗ x | 5–203 | 0.21 | 0.62 |
LOD, limit of detection; LOQ, limit of quantification, RT, retention time; R, correlation coefficient.
Table 9.
FA compositions and main specific ratios of 7 maize oils.
| Fatty Acid | Fatty Acid Content (%) | |||||||
|---|---|---|---|---|---|---|---|---|
| Control | HansePlant | Manure | Agroflorin | Bioecohum | Biohumus | Tumat | ||
| C4:0 | Butyric | 0.04 ± 0.00 g | 0.10 ± 0.05 g | 0.02 ± 0.01 g | 0.08 ± 0.01 g | 0.05 ± 0.02 g | 0.07 ± 0.01 g | 0.06 ± 0.01 g |
| C6:0 | Caproic | 0.06 ± 0.01 g | 0.15 ± 0.08 g | 0.05 ± 0.01 g | 0.13 ± 0.00 g | 0.11 ± 0.06 g | 0.10 ± 0.00 g | 0.15 ± 0.01 g |
| C8:0 | Caprylic | ND | 0.04 ± 0.04 g | ND | 0.20 ± 0.02 g | 0.01 ± 0.01 g | ND | 0.04 ± 0.01 g |
| C10:0 | Capric | ND | 0.09 ± 0.09 g | ND | 0.48 ± 0.02 g | 0.01 ± 0.01 g | 0.01 ± 0.00 g | 0.02 ± 0.01 g |
| C12:0 | Lauric | 0.01 ± 0.00 g | 0.10 ± 0.01 g | ND | 0.63 ± 0.03 g | 0.02 ± 0.02 g | 0.03 ± 0.01 g | 0.01 ± 0.00 g |
| C14:0 | Myristic | 0.06 ± 0.02 g | 0.15 ± 0.01 g | 0.05 ± 0.00 g | 0.75 ± 0.03 g | 0.06 ± 0.03 g | 0.08 ± 0.01 g | 0.06 ± 0.01 g |
| C15:0 | Pentadecanoic | ND | 0.01 ± 0.01 g | ND | 0.01 ± 0.00 g | ND | ND | ND |
| C16:0 | Palmitic | 15.12 ± 1.06 c | 14.62 ± 0.83 c | 15.93 ± 0.43 c | 14.89 ± 0.10 c | 14.77 ± 1.10 c | 14.28 ± 0.32 c | 15.85 ± 0.44 c |
| C16:1 | Palmitoleic | 0.08 ± 0.03 g | 0.17 ± 0.12 g | 0.10 ± 0.00 g | 0.63 ± 0.00 g | 0.08 ± 0.02 g | 0.09 ± 0.01 g | 0.09 ± 0.01 g |
| C17:0 | Heptadecanoic | 0.05 ± 0.02 g | 0.03 ± 0.01 g | 0.07 ± 0.00 g | 0.05 ± 0.00 g | 0.04 ± 0.02 g | 0.05 ± 0.01 g | 0.06 ± 0.01 g |
| C17:1 | cis-Heptadecanoic | 0.01 ± 0.00 g | 0.01 ± 0.01 g | 0.03 ± 0.00 g | 0.02 ± 0.01 g | 0.01 ± 0.01 g | ND | 0.01 ± 0.00 g |
| C18:0 | Stearic | 2.08 ± 0.31 d | 2.09 ± 0.12 d | 2.29 ± 0.12 d | 2.41 ± 0.03 d | 2.33 ± 0.26 d | 2.30 ± 0.05 d | 2.43 ± 0.11 d |
| C18:1n9t | Oleic trans | 0.05 ± 0.00 g | ND | 0.01 ± 0.00 g | 0.02 ± 0.01 g | 0.08 ± 0.02 g | 0.06 ± 0.01 g | 0.03 ± 0.0 g |
| C18:1n9c | Oleic | 30.82 ± 0.63 b | 31.37 ± 0.48 b | 33.89 ± 0.39 b | 30.31 ± 0.20 b | 30.80 ± 0.38 b | 31.14 ± 0.20 b | 32.86 ± 0.14 b |
| C18:2n6t | Linoleic trans | 0.01 ± 0.01 g | 0.01 ± 0.01 g | 0.03 ± 0.01 g | ND | 0.01 ± 0.01 g | 0.02 ± 0.01 g | 0.03 ± 0.00 g |
| C18:2n6c | Linoleic | 50.13 ± 2.05 a | 49.50 ± 1.62 a | 46.21 ± 1.25 a | 47.99 ± 0.80 a | 50.35 ± 1.61 a | 50.95 ± 0.63 a | 47.11 ± 0.82 a |
| C20:0 | Arachidic | 0.03 ± 0.02 g | 0.01 ± 0.01 g | ND | ND | 0.02 ± 0.01 g | ND | 0.02 ± 0.00 g |
| C18:3n6c | γ-Linolenic | 0.76 ± 0.43 e | 0.21 ± 0.02 e | 0.38 ± 0.01 e | 0.22 ± 0.02 e | 0.29 ± 0.04 e | 0.28 ± 0.03 e | 0.38 ± 0.02 e |
| C18:3n3c | α-Linolenic | 0.30 ± 0.21 ef | 2.21 ± 0.02 ef | 0.38 ± 0.01 ef | 1.04 ± 0.01 ef | 0.73 ± 0.41 ef | 0.38 ± 0.03 ef | 0.38 ± 0.02 ef |
| C20:1n9c | Gondoic | 0.19 ± 0.05f g | 0.13 ± 0.03 fg | 0.28 ± 0.01 fg | 0.14 ± 0.02 fg | 0.18 ± 0.03 fg | 0.19 ± 0.01 fg | 0.25 ± 0.0f g |
| C20:3n3c | Eicosatrienoic | 0.03 ± 0.03 g | 0.01 ± 0.01 g | 0.09 ± 0.01 g | 0.01 ± 0.00 g | 0.05 ± 0.02 g | 0.04 ± 0.00 g | 0.09 ± 0.00 g |
| C22:1n9c | Erucic | 0.03 ± 0.03 g | 0.01 ± 0.00 g | 0.09 ± 0.01 g | 0.02 ± 0.01 g | 0.05 ± 0.02 g | 0.04 ± 0.00 g | 0.09 ± 0.00 g |
| C20:3 | Eicosatrienoic | 0.03 ± 0.03 g | ND | ND | 0.02 ± 0.01 g | 0.02 ± 0.02 g | ND | ND |
| C24:1n9c | Nervonic | 0.03 ± 0.01 g | ND | 0.09 ± 0.00 g | 0.01 ± 0.00 g | 0.02 ± 0.00 g | 0.04 ± 0.00 g | 0.05 ± 0.00 g |
| SFA | 17.45 ± 1.45 | 17.37 ± 1.42 | 18.41 ± 0.57 | 19.61 ± 0.21 | 17.39 ± 1.52 | 16.91 ± 0.38 | 18.66 ± 0.62 | |
| USFA | 82.36 ± 3.47 | 83.60 ± 2.30 | 81.45 ± 1.71 | 80.35 ± 0.32 | 82.50 ± 2.53 | 83.10 ± 0.89 | 81.20 ± 1.03 | |
| MUFA | 31.12 ± 0.73 | 31.67 ± 0.63 | 34.39 ± 0.42 | 31.09 ± 0.22 | 31.07 ± 0.44 | 31.46 ± 0.22 | 33.25 ± 0.16 | |
| PUFA | 51.24 ± 2.74 | 51.93 ± 1.67 | 47.06 ± 1.29 | 49.26 ± 0.10 | 51.43 ± 2.09 | 51.64 ± 0.68 | 47.95 ± 0.87 | |
| Omega-6 | 50.13 ± 2.05 | 49.50 ± 1.62 | 46.21 ± 1.25 | 47.99 ± 0.08 | 50.35 ± 1.61 | 50.95 ± 0.63 | 47.11 ± 0.82 | |
| Omega-3 | 0.30 ± 0.43 | 2.21 ± 0.02 | 0.38 ± 0.02 | 1.04 ± 0.02 | 0.73 ± 0.04 | 0.38 ± 0.03 | 0.38 ± 0.02 | |
| PUFA/SFA | 2.94 | 2.99 | 2.56 | 2.51 | 2.96 | 3.05 | 2.57 | |
| Omega-6/omega-3 | 167.10 | 22.40 | 121.61 | 46.36 | 69.45 | 135.85 | 123.96 | |
The mean standard deviation (SD) is used to express each value. SFA, saturated fatty acid; MUFA, monounsaturated fatty acid; USFA, unsaturated fatty acid; PUFA, polyunsaturated fatty acid; ND, not detected. The values within each column are followed by different letters and are significantly different (p < 0.05).
Table 10.
FA compositions and main specific ratios of 7 soybean oils.
| Fatty Acid | Fatty Acid Content (%) | |||||||
|---|---|---|---|---|---|---|---|---|
| Control | HansePlant | Manure | Agroflorin | Bioecohum | Biohumus | Tumat | ||
| C4:0 | Butyric | 0.06 ± 0.04 f | 0.05 ± 0.01 f | 0.03 ± 0.00 f | 0.02 ± 0.00 f | 0.03 ± 0.01 f | 0.03 ± 0.01 f | 0.03 ± 0.01 f |
| C6:0 | Caproic | 0.08 ± 0.03f | 0.07 ± 0.01 f | 0.04 ± 0.01 f | 0.03 ± 0.00 f | 0.04 ± 0.00 f | 0.04 ± 0.01 f | 0.04 ± 0.01 f |
| C8:0 | Caprylic | ND | ND | ND | ND | ND | 0.01 ± 0.01 g | ND |
| C10:0 | Capric | 0.02 ± 0.01 g | ND | ND | ND | 0.01 ± 0.01 g | 0.01 ± 0.01 g | ND |
| C12:0 | Lauric | 0.01 ± 0.01 g | ND | ND | ND | 0.01 ± 0.01 g | 0.01 ± 0.00 g | ND |
| C14:0 | Myristic | 0.13 ± 0.01 if | 0.11 ± 0.01 if | 0.11 ± 0.01 if | 0.10 ± 0.00 if | 0.15 ± 0.02 if | 0.13 ± 0.02 if | 0.13 ± 0.02 if |
| C15:0 | Pentadecanoic | 0.01 ± 0.00 fg | 0.01 ± 0.01 fg | 0.01 ± 0.01 fg | 0.01 ± 0.00 fg | 0.02 ± 0.01 fg | 0.01 ± 0.00 fg | 0.01 ± 0.00 fg |
| C16:0 | Palmitic | 14.77 ± 0.80 c | 13.64 ± 0.10 c | 13.40 ± 0.19 c | 13.34 ± 0.07 c | 15.68 ± 1.69 c | 14.01 ± 0.19 c | 13.51 ± 0.30 c |
| C16:1 | Palmitoleic | 0.10 ± 0.01 if | 0.08 ± 0.01 if | 0.08 ± 0.01 if | 0.09 ± 0.01 if | 0.12 ± 0.02 if | 0.12 ± 0.02 if | 0.10 ± 0.02 if |
| C17:0 | Heptadecanoic | 0.13 ± 0.01 hi | 0.11 ± 0.00 hi | 0.13 ± 0.01 hi | 0.14 ± 0.00 hi | 0.17 ± 0.04 hi | 0.15 ± 0.02 hi | 0.14 ± 0.02 hi |
| C17:1 | cis-Heptadecanoic | 0.05 ± 0.01 if | 0.04 ± 0.01 if | 0.05 ± 0.01 if | 0.05 ± 0.00 if | 0.06 ± 0.01 if | 0.06 ± 0.01 if | 0.05 ± 0.01 if |
| C18:0 | Stearic | 7.55 ± 0.64 e | 7.51 ± 0.56 e | 7.42 ± 0.39 e | 7.68 ± 0.02 e | 9.73 ± 1.63 e | 8.16 ± 0.63 e | 8.40 ± 0.71 e |
| C18:1n9t | Oleic trans | 0.02 ± 0.00 fg | ND | 0.01 ± 0.00 fg | 0.02 ± 0.00 fg | 0.02 ± 0.00 fg | 0.02 ± 0.01 fg | 0.01 ± 0.00fg |
| C18:1n9c | Oleic | 28.03 ± 1.19 b | 25.93 ± 0.28 b | 24.96 ± 0.03 b | 25.98 ± 0.06 b | 28.61 ± 2.31 b | 25.42 ± 0.88 b | 26.16 ± 1.01 b |
| C18:2n6t | Linoleic trans | 0.04 ± 0.02 if | 0.04 ± 0.01 if | 0.05 ± 0.00 if | 0.05 ± 0.00 if | 0.07 ± 0.01 if | 0.06 ± 0.01 if | 0.06 ± 0.02 if |
| C18:2n6c | Linoleic | 38.42 ± 4.13 a | 39.86 ± 1.80 a | 40.61 ± 1.38 a | 38.60 ± 0.06 a | 36.59 ± 1.48 a | 37.60 ± 1.32 a | 37.59 ± 1.43 a |
| C20:0 | Arachidic | 0.03 ± 0.01 f | 0.01 ± 0.00 f | 0.02 ± 0.00 f | 0.02 ± 0.00 f | 0.05 ± 0.02 f | 0.03 ± 0.01 f | 0.02 ± 0.01 f |
| C18:3n3c | α-Linolenic | 8.57 ± 0.80 d | 10.63 ± 0.47 d | 9.83 ± 0.39d | 10.37 ± 0.02 d | 11.12 ± 1.47 d | 10.74 ± 0.42 d | 9.87 ± 0.56 d |
| C18:3n6c | γ-Linolenic | 0.70 ± 0.11 f | 0.77 ± 0.08 f | 0.90 ± 0.10 f | 0.84 ± 0.02 f | 1.27 ± 0.21 f | 1.02 ± 0.23 f | 1.04 ± 0.21 f |
| C20:1n9c | Gondoic | 0.25 ± 0.05 hi | 0.21 ± 0.03 hi | 0.27 ± 0.03 hi | 0.33 ± 0.01 hi | 0.39 ± 0.10 hi | 0.31 ± 0.06 hi | 0.33 ± 0.06 hi |
| C21:0 | Heneicosanoic | 0.01 ± 0.00 f | 0.02 ± 0.00 f | 0.04 ± 0.01 f | 0.04 ± 0.00 f | 0.05 ± 0.02 f | 0.04 ± 0.01 f | 0.04 ± 0.01 f |
| C20:2 | Eicosadienoic | 0.02 ± 0.01 f | 0.03 ± 0.01 f | 0.04 ± 0.01 f | 0.04 ± 0.00 f | 0.05 ± 0.02 f | 0.04 ± 0.01 f | 0.04 ± 0.01 f |
| C20:3n3c | Eicosatrienoic | 0.02 ± 0.01 gh | ND | 0.62 ± 0.06 gh | 0.69 ± 0.02 gh | 0.81 ± 0.27 gh | 0.63 ± 0.15 gh | 0.77 ± 0.16 gh |
| C22:1n9c | Erucic | 0.45 ± 0.13 fg | 0.40 ± 0.10 fg | 0.61 ± 0.06 fg | 0.63 ± 0.02 fg | 0.89 ± 0.26 fg | 0.65 ± 0.15 fg | 0.81 ± 0.16 fg |
| C20:3 | Eicosatrienoic | 0.46 ± 0.14 fg | 0.41 ± 0.10 fg | 0.63 ± 0.06 fg | 0.69 ± 0.02 fg | 0.81 ± 0.26 fg | 0.63 ± 0.15 fg | 0.78 ± 0.15 fg |
| C22:2 | Docosadienoic | ND | 0.01 ± 0.00 fg | 0.02 ± 0.01 fg | 0.03 ± 0.01 fg | 0.04 ± 0.02 fg | 0.02 ± 0.01 fg | 0.04 ± 0.01 fg |
| C20:5n3c | Eicopentaenoic | 0.08 ± 0.01 if | 0.07 ± 0.03 if | 0.15 ± 0.03 if | 0.16 ± 0.02 if | 0.12 ± 0.01 if | 0.07 ± 0.01 if | ND |
| C24:1n9c | Nervonic | 0.07 ± 0.03 if | 0.05 ± 0.01 if | 0.05 ± 0.01 if | 0.06 ± 0.00 if | 0.24 ± 0.07 if | 0.07 ± 0.01 if | 0.11 ± 0.11 if |
| SFA | 22.77 ± 1.59 | 21.50 ± 0.70 | 21.17 ± 0.60 | 21.37 ± 0.08 | 25.91 ± 3.42 | 22.61 ± 0.90 | 22.30 ± 1.07 | |
| USFA | 76.72 ± 6.52 | 78.04 ± 2.80 | 78.14 ± 2.09 | 77.85 ± 0.22 | 80.15 ± 6.31 | 76.66 ± 3.31 | 76.81 ± 3.62 | |
| MUFA | 28.49 ± 1.29 | 26.31 ± 0.33 | 25.40 ± 0.08 | 26.50 ± 0.07 | 29.41 ± 2.50 | 25.97 ± 0.98 | 26.74 ± 1.10 | |
| PUFA | 48.23 ± 5.23 | 51.73 ± 2.47 | 52.74 ± 2.01 | 51.36 ± 0.14 | 50.74 ± 3.81 | 50.69 ± 2.33 | 50.08 ± 2.53 | |
| Omega-6 | 38.42 ± 4.13 | 39.86 ± 1.80 | 40.61 ± 1.38 | 38.60 ± 0.06 | 36.59 ± 1.48 | 37.60 ± 1.32 | 37.59 ± 1.43 | |
| Omega-3 | 8.65 ± 0.8 | 10.70 ± 0.50 | 9.97 ± 0.41 | 10.52 ± 0.03 | 11.24 ± 1.59 | 10.8. ± 0.48 | 9.87 ± 0.56 | |
| PUFA/SFA | 2.12 | 2.41 | 2.49 | 2.40 | 1.96 | 2.24 | 2.25 | |
| Omega-6/omega-3 | 4.44 | 3.73 | 4.07 | 3.67 | 3.26 | 3.48 | 3.81 | |
The mean standard deviation (SD) is used to express each value. SFA, saturated fatty acid; MUFA, monounsaturated fatty acid; USFA, unsaturated fatty acid; PUFA, polyunsaturated fatty acid; ND, not detected. The values within each column are followed by different letters and are significantly different (p < 0.05).
Table 11.
Euclidean distances in maize clustering analysis.
| Control | Biohumus | Tumat | Manure | Bioecohum | Agroflorin | HansePlant | |
|---|---|---|---|---|---|---|---|
| Control | 0 | 33 | 45 | 46.9 | 98.2 | 121 | 145 |
| Biohumus | *** | 0 | 14 | 16.1 | 66.6 | 90 | 114 |
| Tumat | *** | *** | 0 | 3.7 | 54.9 | 78 | 102 |
| Manure | *** | *** | *** | 0 | 52.9 | 76 | 100 |
| Bioecohum | ** | *** | *** | *** | 0 | 23 | 48 |
| Agroflorin | ** | ** | ** | ** | *** | 0 | 26 |
| HansePlant | * | ** | ** | ** | *** | *** | 0 |
The upper triangle is the result of Euclidean distances, and the lower triangle is the result of a significance test. * p < 0.05; ** p < 0.01; *** p < 0.001.
Table 12.
Euclidean distances in soybean clustering analysis.
| Control | Bioecohum | HansePlant | Manure | Agroflorin | Biohumus | Tumat | |
|---|---|---|---|---|---|---|---|
| Control | 0 | 4.93 | 5.00 | 5.27 | 5.94 | 7.33 | 8.00 |
| Bioecohum | ** | 0 | 3.20 | 3.18 | 4.71 | 6.35 | 4.74 |
| HansePlant | ** | *** | 0 | 2.10 | 4.37 | 4.31 | 4.53 |
| Manure | ** | *** | *** | 0 | 3.20 | 3.31 | 3.73 |
| Agroflorin | ** | ** | *** | *** | 0 | 3.22 | 3.0 |
| Biohumus | ** | ** | ** | ** | *** | 0 | 2.97 |
| Tumat | * | ** | ** | ** | ** | *** | 0 |
The upper triangle is the result of Euclidean distances, and the lower triangle is the result of a significance test. * p < 0.05; ** p < 0.01; *** p < 0.001.
Table 13.
Pearson correlation coefficient ® between qualities and fatty acid ratios of maize.
| Moisture | Fat | Protein | Fiber | Starch | SFA | MUFA | PUFA | Omega-6 | Omega-3 | PUFA/SFA | Omega-6/Omega-3 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Moisture | 1.00 | 0.34 | 0.10 | 0.12 | −0.12 | 0.44 | 0.29 | −0.52 | −0.35 | −0.47 | −0.50 | 0.02 |
| Fat | * | 1.00 | 0.74 | 0.53 | −0.59 | −0.26 | 0.21 | 0.05 | 0.09 | 0.12 | 0.19 | −0.14 |
| Protein | * | ** | 1.00 | 0.62 | −0.94 | −0.45 | 0.55 | −0.13 | −0.04 | −0.26 | 0.21 | 0.43 |
| Fiber | * | ** | ** | 1.00 | −0.59 | −0.47 | 0.04 | 0.17 | 0.31 | −0.29 | 0.38 | 0.30 |
| Starch | * | ** | *** | ** | 1.00 | 0.22 | −0.68 | 0.37 | 0.26 | 0.41 | 0.04 | −0.56 |
| SFA | * | * | ** | ** | * | 1.00 | 0.29 | −0.74 | −0.77 | −0.05 | −0.95 | −0.23 |
| MUFA | * | * | ** | * | ** | * | 1.00 | −0.84 | −0.82 | −0.28 | −0.58 | 0.26 |
| PUFA | ** | * | * | * | * | ** | *** | 1.00 | 0.96 | 0.40 | 0.92 | −0.20 |
| Omega-6 | * | * | * | * | ** | *** | *** | *** | 1.00 | 0.13 | 0.92 | 0.02 |
| Omega-3 | ** | * | * | * | * | * | * | ** | * | 1.00 | 0.21 | −0.87 |
| PUFA/SFA | ** | * | * | * | * | *** | ** | *** | *** | * | 1.00 | 0.05 |
| Omega-6/ omega-3 | * | * | * | * | ** | * | * | * | * | *** | * | 1.00 |
The Pearson correlation coefficient results are shown in the upper triangle, while the significance test results are shown in the lower triangle. * p < 0.05; ** p < 0.01; *** p < 0.001.
Table 14.
Pearson correlation coefficient (r) between qualities and fatty acid ratios of soybean.
| Moisture | Fat | Protein | Fiber | Starch | SFA | MUFA | PUFA | Omega-6 | Omega-3 | PUFA/SFA | Omega-6/Omega-3 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Moisture | 1.00 | −0.72 | −0.77 | −0.80 | 0.20 | 0.07 | 0.03 | −0.49 | −0.54 | 0.01 | −0.26 | −0.21 |
| Fat | ** | 1.00 | 0.53 | 0.77 | 0.13 | −0.41 | −0.45 | 0.48 | 0.63 | −0.29 | 0.52 | 0.44 |
| Protein | *** | ** | 1.00 | 0.64 | −0.21 | −0.42 | −0.28 | 0.66 | 0.78 | 0.05 | 0.61 | 0.21 |
| Fibre | *** | *** | ** | 1.00 | −0.48 | −0.12 | −0.25 | 0.69 | 0.36 | 0.23 | 0.37 | −0.09 |
| Starch | * | * | * | ** | 1.00 | −0.29 | −0.29 | −0.20 | 0.35 | −0.46 | 0.14 | 0.51 |
| SFA | * | ** | ** | * | * | 1.00 | 0.85 | −0.36 | −0.79 | 0.33 | −0.93 | −0.49 |
| MUFA | * | ** | * | * | * | *** | 1.00 | −0.63 | −0.66 | −0.06 | −0.91 | −0.10 |
| PUFA | ** | ** | ** | ** | * | * | ** | 1.00 | 0.55 | 0.59 | 0.67 | −0.36 |
| Omega-6 | ** | ** | *** | * | * | *** | ** | ** | 1.00 | −0.26 | 0.85 | 0.53 |
| Omega-3 | * | * | * | * | ** | * | * | ** | * | 1.00 | −0.04 | −0.95 |
| PUFA/SFA | * | ** | ** | * | * | *** | *** | ** | *** | * | 1.00 | 0.26 |
| omega-6/ omega-3 | * | * | * | * | ** | * | * | * | ** | *** | * | 1.00 |
The Pearson correlation coefficient results are shown in the upper triangle, while the significance test results are shown in the lower triangle. * p < 0.05; ** p < 0.01; *** p < 0.001.
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Toishimanov, M.; Suleimenova, Z.; Myrzabayeva, N.; Dossimova, Z.; Shokan, A.; Kenenbayev, S.; Yessenbayeva, G.; Serikbayeva, A. Effects of Organic Fertilizers on the Quality, Yield, and Fatty Acids of Maize and Soybean in Southeast Kazakhstan. Sustainability 2024, 16, 162. https://doi.org/10.3390/su16010162
AMA Style
Toishimanov M, Suleimenova Z, Myrzabayeva N, Dossimova Z, Shokan A, Kenenbayev S, Yessenbayeva G, Serikbayeva A. Effects of Organic Fertilizers on the Quality, Yield, and Fatty Acids of Maize and Soybean in Southeast Kazakhstan. Sustainability. 2024; 16(1):162. https://doi.org/10.3390/su16010162
Chicago/Turabian StyleToishimanov, Maxat, Zhulduz Suleimenova, Nurgul Myrzabayeva, Zhanna Dossimova, Aksholpan Shokan, Serik Kenenbayev, Gulvira Yessenbayeva, and Assiya Serikbayeva. 2024. "Effects of Organic Fertilizers on the Quality, Yield, and Fatty Acids of Maize and Soybean in Southeast Kazakhstan" Sustainability 16, no. 1: 162. https://doi.org/10.3390/su16010162
APA StyleToishimanov, M., Suleimenova, Z., Myrzabayeva, N., Dossimova, Z., Shokan, A., Kenenbayev, S., Yessenbayeva, G., & Serikbayeva, A. (2024). Effects of Organic Fertilizers on the Quality, Yield, and Fatty Acids of Maize and Soybean in Southeast Kazakhstan. Sustainability, 16(1), 162. https://doi.org/10.3390/su16010162
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