Effect of Iron Application on Rice Plants in Improving Grain Nutritional Quality in Northeastern of Thailand
1
Department of Agronomy, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002, Thailand
2
Agricultural Center—Rice Research Station, Louisiana State University, 1373 Caffey Rd., Rayne, LA 70578, USA
*
Author to whom correspondence should be addressed.
Sustainability 2022, 14(23), 15756; https://doi.org/10.3390/su142315756
Submission received: 6 August 2022
/
Revised: 27 October 2022
/
Accepted: 17 November 2022
/
Published: 26 November 2022
(This article belongs to the Section Sustainable Agriculture)
Abstract
:Iron (Fe) deficiency in humans caused by inadequate dietary intake is a global nutritional problem. The field experiments in this paper were conducted in the same paddy field over two consecutive years during the dry seasons of 2017 and 2018. The aims of the experiments were to evaluate the effects of iron application methods (soil or foliar alone and a combination of soil + foliar) on the Fe content in brown rice grain and to compare the grain yields of three rice cultivars, namely Chinat1 (poor Fe grain concentration), Riceberry and Tubtim Chumpae (rich Fe grain concentration). The results show that all iron application methods significantly increase the iron content of brown rice grains in comparison with non-iron application in two cropping years. The iron application to the soil combined with foliar gave the highest iron content in the brown rice grain. However, the responses to the iron application methods were different among rice cultivars. The highest grain iron contents of Chainat1 and Riceberry were shown in the combination of soil and foliar application, whereas Tubtim Chumpae had the highest grain iron content in the foliar application alone. The differences in grain yield were affected by the rice cultivar, but not by iron application methods. The Chainat1 produced the highest grain yield. In addition, Chainat1 had the strongest correlation between brown rice grain iron content and grain yield for both cropping years.
1. Introduction
Rice is the most widely consumed food crop for more than half of the world’s human populations. It is the main source of energy and essential minerals, but it still has a lower iron content than is required to meet the recommended dietary allowances (RDAs) for humans [1,2]. Low dietary diversity and an inadequate daily intake are the main reasons for the widespread occurrence of iron (Fe) deficiency in humans, leading to severe health complications, such as lowered immunity, impaired mental and psychomotor development in children and diminished working capacity in adults, and it represents the most common cause of anemia, affecting two billion people, of whom most are in developing countries [3,4].
Iron is one of the essential elements for plants, and it is a cofactor for approximately 140 enzymes that catalyze unique biochemical reactions, but with low use and low mobility characteristics. Plants need iron more than the other micronutrients [5]. There are several potential approaches to increase the iron content in staple food crops, including fortification and supplementation programs [6], as well as conventional breeding and genetic engineering [7]. Although rice fortification has proven to be effective for certain nutrients, it is costly. As such, many people in poor countries cannot afford fortified rice [8]. Biotechnological approaches and plant-breeding programs to increase the Fe content in rice grains are longer-term strategies [9]. More rapid methods need to be developed, along with longer-term strategies that will address the present severe problem of Fe deficiencies in humans globally. Agriculture is the primary source of all nutrients required for crops and humans, and fertilization is the key strategy of nutrient-integrated management in agronomic approaches to enhance crop qualities and yields [10]. Iron fertilization management is considered as a rapid and efficient way to reach higher Fe contents in grain in recent years [11,12,13]. However, Fe application is often less effective, because Fe can convert to an unavailable form when applied to poor soil. The immobility of Fe can cause Fe deficiency in plants. [10,12,13,14,15]. The foliar application of nutrients is an important crop management strategy to maximize crop yields and concentrations of micronutrients in edible parts. Several studies have demonstrated that the foliar application of micronutrients including Fe increases their concentrations [16,17,18].
Many studies have focussed more on increasing grain yield, but not grain quality [19]. Grain quality characteristics have a strong influence on consumer attraction, as consumers prefer high-quality produce [20,21]. We hypothesized that an iron application on rice plants can increase the Fe content in rice grains. Thus, we tested the effects of different Fe application methods on three brown rice cultivars, and measured the grain iron content, growth and grain yield. The rice was grown under supplemental irrigation during the dry season in the northeast of Thailand. We expected that this study would prove the importance of Fe management in rice cultivation for increasing food nutrition and yield.
2. Materials and Methods
2.1. Experimental Site
The experiments were conducted in the farmer’s field during January to May 2017 and January to May 2018 at Namphong district, Khon Kaen province, northeastern Thailand (latitude; 16°44′13.6″ N, longitude; 102°58′35.4″ E). The soil in the paddy field was a sandy loam soil.
2.2. Experimental Design and Treatments
The experiments were set up as a split-plot design with four replications. The plot sizes were 4 × 4 m, and each plot was separated by ridges. The main plots consisted of the iron fertilizer application methods; iron soil applied alone (Fe supplied 5 kg/ha), iron foliar applied alone (Fe supplied 1.5 kg/ha) and soil combined with foliar (Fe supplied 3.25 kg/ha). We also had a non-iron-application plot as a control. Three rice cultivars, which comprised Chainat1 (poor Fe grain concentration), Riceberry and Tubtim Chumpae (rich Fe grain concentration), were assigned as sub plots. The initial grain iron contents of the Chainat1, Riceberry and Tubtim Chumpae were 6.59, 15.50 and 13.98 mg/kg, respectively [22,23].
2.3. Rice Cultivation
Rice seeds were soaked in clear water for 48 h and incubated moist for 24 h until germinated, and were then sown in the seedbed. The seedlings were transplanted after 30 days of nursery in the seedbed. We transplanted the rice seedling with 25 × 25 cm spacing between a single plant. The synthetic fertilizer grade 16-8-8 (N-P2O5-K2O) was applied to the plots at the rate of 156 kg ha−1, in two splits. The first application was 178 kg ha−1 at 30 days after transplanting (DAT), and another 178 kg ha−1 at the panicle initiation stage. For the iron soil application treatment, we applied 5 kg Fe ha−1 of iron sulfate powder [FeSO4.7H2O (1% Fe)] to the soil at the panicle initiation stage. The foliar application treatment was carried out by spraying 1.5 g Fe L−1 of the foliar solution prepared from dissolving Fe iron sulfate powder [FeSO4.7H2O (1% Fe)] in distilled water. The spraying of the iron sulphate solution was carried out by using a hand-held pump sprayer at the rate of 1000 L ha−1 on the plant leaves at two weeks after flowering. The recommended time for spraying was in the morning around 10 am. The solution was sprayed on the plants until the whole plants were wet and the solution began to drip from the leaves.
The plots were irrigated three times at the field capacity for the first 14 days after transplanting. After that, the water levels in the plots were maintained at 10 cm above the soil surface until 10 days prior to harvest. Hand weeding was carried out at 30 and 60 days after transplanting (DAT). Pesticide was not used in this experiment throughout the entire the growth period.
2.4. Sampling and Measurement
2.4.1. Determination of Plant Growths and Yields
We recorded plant heights and tiller numbers at 30, 60 and 90 DAT by sampling five hills from each plot. Plant heights were measured from the bases of plants to the leaf tips. Shoot dry weights were recorded at 90 DAT by sampling ten hills from each plot, then the shoot dry weights per hectare were determined (data not shown). At harvest, five hills from sampling area of each plot were taken for the measuring of the panicle numbers, the grain numbers per panicle and the 1000-grain weights. The rice grain yields were collected from 6 m2 of each plot. We determined the dry weights of the grains at 14% moisture, and then calculated the average grain yields per hectare.
2.4.2. Grain Fe Concentration Measurement
One gram of grain was sampled from the grain yield measurement for Fe concentration analysis. The husks were removed by using a laboratory-scale dehulling machine, and then the brown rice kernel was used for the iron concentration analysis. The analysis was carried out using the atomic absorption spectrophotometry method [24]. The samples were read for the Fe concentration by using an atomic absorption spectrophotometer (AAS), before being compared with the concentration of standard solution of iron [25]. The iron content was computed by concentration (mg/kg) × grain yield (kg/ha).
2.4.3. Shoot Fe Concentration Measurement
We obtained the Fe concentrations by analyzing the shoot samples that we collected at 90 DAT. The analysis was the same process as the Fe concentration analysis in grain. The iron uptake in the shoots was computed by concentration (mg/kg) × shoot dry weight (kg/ha).
2.4.4. Statistical Analysis
The statistical analysis was conducted using the general linear mixed model (GLMM). Mean comparisons were performed using the Tukey HSD test (SAS University Edition). The data passed our tests for normality and homogeneity of variances of the residuals. In all cases we used type-III tests of fixed effects [26].
3. Results
3.1. Soil Characterizations
The soil physicochemical properties of the experimental sites were determined each year at the beginning of the growing season (Table 2). The soil fertility, as indicated by the soil’s characteristics, was generally favorable for rice production. The soil’s pH was in the neutral range, and the exchangeable potassium and calcium were very high compared with the available phosphorus. The content of available Fe was low in the first year and increased in the second year. The increase of available Fe was probably due to the iron accumulation in the soil from the Fe fertilizer’s application in the previous year.
3.2. Rice Plant Growths
The iron fertilizer application methods had no significant effect on plant height at 30, 60 or 90 DAT in the statistical model (Table 3). However, the rice cultivars resulted in significantly different (p ≤ 0.01) plant heights at 30, 60 and 90 DAT in the statistical model (Table 3). The highest plant height was observed in the Chainat1 cultivar. There were no interaction effects of the iron application methods with the cultivars on the plant height in the present experiment.
The tiller numbers at 30, 60 and 90 DAT were not affected by the iron application methods, according to the statistical model (Table 4). However, the tiller numbers were significantly different (p ≤ 0.01) between rice cultivars at 30, 60 and 90 DAT in the statistical model (Table 3). The highest tiller number was observed in the Chainat1 cultivar. There were no interaction effects of the iron application methods with the rice cultivars for the tiller numbers in this study.
3.3. Yields and Yield Components
The iron fertilizer application methods had no significant effect (p ≤ 0.05) on the panicle numbers per hill, grain numbers per panicle, 1000 grain weights, filled grain percentages or grain yields of the rice in the statistical model (Table 4). There were significant differences in the panicle numbers, 1000 grain weights, filled grain percentages and grain yields (p ≤ 0.01) of the rice between the cultivars in the statistical model (Table 4). The Chainat1 cultivar produced the highest grain number per panicle, 1000 grain weight, filled grain percentage and grain yield in the present experiment. The grain yield was significantly higher in 2018 than in2017 (Table 4).
3.4. Iron Contents in Rice Grains
The iron application methods had significant effects (p ≤ 0.01) on the brown rice grain’s iron contents in the statistical model (Table 5). The rice cultivars had significant effects (p ≤ 0.01) on brown rice grain’s iron contents in the combined analysis of the two years (Table 5). The highest iron content of the brown rice grain was observed in Chainat1.
The data analysis showed significant (p ≤ 0.05) interaction effects of the Fe application methods with rice cultivars on the brown rice grain’s iron contents in 2017 and 2018 (Table 5). The significant (p ≤ 0.05) interaction also showed for the iron application methods with different cultivars and years (Table 5).
In 2017, the highest brown rice grain iron content was obtained in the soil-combined-with-foliar application for Riceberry, while no significant differences were identified among the applied iron fertilizer application methods for Chainat1 and Tubtim Chumpae (Figure 1a). In 2018, the highest brown rice grain iron contents were observed in soil-combined-with-foliar application for Riceberry and Tubtim Chumpae, while the maximum brown rice grain iron content was attained in the soil application alone, but was not significantly different from the foliar application alone for Chainat1 (Figure 1b).
3.5. Iron Uptakes in Shoots
The iron application methods had significant effects (p ≤ 0.01) on the shoot iron uptake at 90 DAT in the statistical model (Table 5). The highest shoot iron uptake of all of the rice cultivars was found in the treatment that combined the soil and foliar applications. All iron fertilizer application methods gave significantly higher shoot iron uptakes for the Chainat1 and Riceberry cultivars, but not for Tubtim Chumpae (Figure 1b).
The rice cultivars had significant effects (p ≤ 0.01) on the shoot iron uptake at 90 DAT in the statistical model (Table 5). The highest shoot iron uptake was observed in the Chainat1 cultivar in the present experiment.
3.6. Relationship between Grain Iron Concentration and Yield
The brown rice grain’s iron concentration was not significantly correlated with grain yield in either cropping year (Figure 2). We noticed that the correlation value of the brown rice grain’s iron concentration with the grain yield was higher in 2018 (high soil iron concentration) than in 2017 (Figure 2). Chainat 1 (poor iron concentration) was positively correlated with the brown rice grain’s iron concentration and yield in both cropping years (Figure 3), whereas Riceberry (rich iron concentration) was negatively correlated with the brown rice grain’s iron concentration and yield in both cropping years (Figure 3). For Tubtim Chumpae (rich iron concentration), the brown rice grain’s iron concentration was negatively correlated with the yield in 2017 (low soil iron concentration), but positively correlated in 2018 (high soil iron concentration) (Figure 3).
4. Discussion
4.1. Brown Rice Grain’s Iron Content
In this experiment, all of the iron fertilizer application methods significantly increased the brown rice grains’ iron contents over those without the iron application (control). The highest brown rice grain iron content was obtained in the soil application combined with the foliar application. The soil applications of most iron sources are generally ineffective because of the rapid conversion of soluble iron into a plant unavailable solid Fe(III) form [27,28]. Foliar-applied iron can be absorbed by the leaf epidermis, remobilized and transferred into the grain [29,30]. The application of Fe to the foliar resulted in greater increases in the iron content of the brown rice grain than the Fe application to the soil [11].
In addition, the foliar application of iron at the flowering stage before/during the grain-filling stage is important for increasing grain micronutrients. The foliar application of FeSO4 at panicle initiation combined with the flowering, milking and dough stages can increase the rice grain’s iron content significantly [31]. The translocation of micronutrients from the vegetative tissues to the grain affects the accumulation of the grain micronutrients content, but the translocation is different among rice cultivars [32,33,34].
The rice cultivars responded to the iron application methods differently. Chainat1, the poor-iron-content cultivar, turned out to be very responsive to the iron fertilizer application in the 2017 experiment. The increase of the iron concentration in Chainart1 was higher than in the other rich-iron concentration cultivars such as Riceberry and Tubtim Chumpae. However, this cultivar effect did not show up in the 2018 experiment. This indicates that rice cultivars differed in their responses to the iron fertilizer application methods due to genetic control. This finding is in agreement with Wei et al. (2012) [15]. In the present study, the soil-combined-with-foliar application produced brown rice grain iron contents greater than soil applied alone or foliar applied alone. The brown rice grain’s iron content was significantly higher in 2018 than that of 2017. This was probably due to the residual effect of iron accumulation in the soil before planting the rice in 2018.
4.2. Grain Yields
In the present experiment, all of the iron fertilizer application methods, including the without-application (control) treatments, had no significant effect on the grain yields. However, applying iron fertilizer tended to give higher grain yields than the without-iron application, especially when applied to the soil with a low iron content in 2017 before planting (data not shown). Iron plays a significant role in various physiological and biochemical pathways in plants, including enhancing plant photosynthesis, which can lead to the increase of the grain yield [35]. The iron fertilizer applications significantly increased the spike weight and 1000-grain weight of barley, and consequently increased the grain yield [36]. Foliar iron fertilizer application causing no significantly different grain yields among the rice cultivars was reported by Fang et al. (2008) [12].
Chainat1 (poor Fe grain concentration) produced a significantly higher grain yield than those of Riceberry and Tubtim Chumpae (rich Fe grain concentration) in the present study. This result is in agreement with the finding by Saenchai et al. (2012) [37], who found that RD7 and KDML105 (poor Fe grain concentrations) gave higher grain yields than those of the KPK and IR68144 cultivars (rich Fe grain concentrations). Different rice cultivars respond to an Fe deficiency differently [38,39]. An iron deficiency caused entire leaves to become chlorotic, resulting in the reduction of photosynthesis [40].
The grain yield was significantly higher in 2018 than in2017 in the present experiment. This was probably due to the residual effect of iron accumulation and available P in soil before planting the rice in 2018. Phosphorus plays an important role in increasing tiller numbers and the grain weight of rice [41].
4.3. Iron Uptake
In this study, all iron fertilizer application methods significantly increased the shoot’s iron uptakes over those without an iron application (control). The highest shoot iron uptake was obtained in the soil-combined-with-foliar application. The increase of Fe uptake also increased the translocation of Fe to the grain. The accumulation of iron in the grain was not only achieved through the remobilization of previously stored shoot minerals, but also from the uptake and translocation of minerals during grain filling [4,42]. This finding is in agreement with Yadav et al. (2013) [43].
The rice cultivars responded to the iron application methods differently; Chainat1, the poor-iron-content cultivar, gave the highest shoot iron uptake for all of the iron fertilizer application methods, followed by Riceberry and Tubtim Chumpae, respectively, whereas Tubtim Chumpae, the rich-iron-content cultivar, demonstrated the highest shoot iron of those without an iron application treatment (Figure 2). This might be due to genetic variations of the rice plant. This finding is in agreement with Wang et al. (2021) and Sharma et al. (2013) [44,45].
The shoot iron uptake was significantly higher in 2018 than in 2017. This was probably due to the residual effects of iron and phosphorus accumulation in the soil before the planting of the rice in 2018.
5. Conclusions
The application of iron fertilizer significantly enriches brown rice grains’ iron contents. The application through the soil in combination with the foliar application was the most effective method to increase the iron content in the rice grain. The responsiveness to the Fe fertilizer application methods was different between the rice cultivars. The Chainat1 cultivar (poor Fe grain concentration) seemed to be more responsive to the iron fertilizer application than Riceberry and Tubtim Chumpae (rich Fe grain concentration) when grown under a low-soil-iron content. The grain yields of all of the rice cultivars in this experiment increased with the application of iron fertilizer in both application methods via the soil and foliar.
Author Contributions
Conceptualization, A.P.; Methodology, W.B.; Formal analysis, W.B.; Investigation, W.B.; Resources, W.B.; Data curation, W.B.; Writing—original draft, W.B. and A.P.; Writing—review & editing, W.K., D.L.H. and A.P.; Supervision, A.P.; Project administration, W.B. and A.P. All authors have read and agreed to the published version of the manuscript.
Funding
This research work was financially supported by the Thailand Research Fund (TRF), who we thank for their joint support through the Royal Golden Jubilee Ph.D. (RGJ-PHD) program (Grant No. PHD/0082/2557), and by the Ph.D. research scholarship from Khon Kaen University.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
Not applicable.
Conflicts of Interest
The authors declare no conflict of interest.
References
- Fitzgerald, M.A.; McCouch, S.R.; Hall, R.D. Not just a grain of rice: The quest for quality. Trends Plant Sci. 2009, 14, 133–139. [Google Scholar] [CrossRef]
- Welch, R.M.; Graham, R.D. Breeding for micronutrients in staple food crops from a human nutrition perspective. J. Exp. Bot. 2004, 55, 353–364. [Google Scholar] [CrossRef] [Green Version]
- Murray-Kolb, L.E.; Beard, J.L. Iron deficiency and child and maternal health. Am. J. Clin. Nutr. 2009, 89, 946S–950S. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Sperotto, R.A.; Vasconcelos, M.W.; Grusak, M.A.; Fett, J.P. Effects of different Fe supplies on mineral partitioning and remobilization during the reproductive development of rice (Oryza sativa L.). Rice 2012, 5, 27. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Corey, M.S. Groups: Process and Practice; Wadsworth Publishing Co Inc.: Wadsworth, OR, USA, 2006. [Google Scholar]
- Davidsson, L. Approaches to improve iron availability from complementary foods. J. Nutr. 2003, 133, 1560S–1562S. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Holm, P.B.; Kristiansen, K.N.; Pedersen, H.B. Transgenic approaches in commonly consumed cereals to improve iron and zinc content and bioavailability. J. Nutr. 2002, 132, 514S–516S. [Google Scholar] [CrossRef] [Green Version]
- Poletti, S.; Gruissem, W.; Sautter, C. The nutritional fortification of cereals. Curr. Opin. Biotechnol. 2004, 15, 162–165. [Google Scholar] [CrossRef] [PubMed]
- Schachtman, D.P.; Barker, S.J. Molecular approaches for increasing the micronutrient density in edible portions of food crops. Field Crops Res. 1999, 60, 81–92. [Google Scholar] [CrossRef]
- Rengel, Z.; Batten, G.D.; Crowley, D.E. Agronomic approaches for improving the micronutrient density inedible portions of field crops. Field Crop Res. 1999, 60, 27–40. [Google Scholar] [CrossRef]
- Aciksoz, S.B.; Yazici, A.; Ozturk, L.; Cakmak, I. Biofortification of wheat with iron through soil and foliar application of nitrogen and iron fertilizers. Plant Soil 2011, 349, 215–225. [Google Scholar] [CrossRef]
- Fang, Y.; Wang, L.; Xin, Z.; Zhao, L.; An, X.; Hu, Q. Effect of foliar application of zinc, selenium, and iron fertilizers on nutrient concentration and yield of rice grain in China. J. Agric. Food Chem. 2008, 56, 2079–2084. [Google Scholar] [CrossRef]
- Yuan, L.; Wu, L.; Yang, C.; Lv, Q. Effects of iron and zinc foliar applications on rice plants and their grain accumulation and grain nutritional quality. J. Sci. Food Agric. 2012, 93, 254–261. [Google Scholar] [CrossRef]
- Cakmak, I. Enrichment of cerial grains with zinc: Agronomic or genetic biofortification? Plant Soil 2008, 302, 1–17. [Google Scholar] [CrossRef]
- Wei, Y.; Shohag, M.J.I.; Xiaoe, Y.; Zhang, Y. Effects of foliar iron application on iron concentration in polished rice grain and its bioavailability. J. Agric. Food Chem. 2012, 60, 11433–11439. [Google Scholar] [CrossRef]
- Peleg, Z.; Saranga, Y.; YaZici, A.; Fahima, T.; Ozturk, L.; Cakmak, I. Grain zinc, iron and protein concentrations and zinc-efficiency in wild emmer wheat under contrasting irrigation regimes. Plant Soil 2007, 306, 57–67. [Google Scholar] [CrossRef] [Green Version]
- Li, M.; Wang, S.; Tian, X.; Li, S.; Chen, Y.; Jia, Z.; Liu, K.; Zhao, A. Zinc and iron concentrations in grain milling fractions through combined folia applications of Zn and micronutrients. Field Crops Res. 2016, 187, 135–141. [Google Scholar] [CrossRef]
- Pataco, I.M.; Lidon, F.C.; Ramos, I.; Oliveira, K.; Guerra, M.; Pessoa, M.F.; Carvalho, M.L.; Ramalho, J.C.; Leitao, A.E.; Santos, J.P. Biofortification of durum eheat grains with nutrients. J. Plant Int. 2017, 12, 39–50. [Google Scholar]
- Zhao, D.S.; Li, Q.F.; Zhang, C.Q.; Zhang, C.; Yang, Q.Q.; Pan, L.X.; Ren, X.Y.; Lu, J.; Gu, M.H.; Liu, Q.Q. GS9 acts as a transcriptional activator to regulate rice grain shape and appearance quality. Nat. Commun. 2018, 9, 1240. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Li, M.; Ashraf, U.; Tian, H.; Mo, Z.; Pan, S.; Anjum, S.A.; Duan, M.; Tang, X. Manganese-induced regulations in growth, yield formation, quality characters, rice aroma and enzyme involved in 2-acetyl-1-pyrroline biosynthesis in fragrant rice. Plant Physiol. Biochem. 2016, 103, 167–175. [Google Scholar] [CrossRef]
- Dou, Z.; Tang, S.; Li, G.H.; Liu, Z.H.; Ding, C.Q.; Chen, L.; Wang, S.H.; Ding, Y.F. Application of nitrogen fertilizer at heading stage improves rice quality under elevated temperature during grain-filling stage. Crop Sci. 2017, 57, 2183–2192. [Google Scholar] [CrossRef] [Green Version]
- Rice Science Center. Riceberry. 2016. Available online: http://www.news-articles-rice-rsc-rgdu-knowledge/rice-breedinglab/riceberry-variety (accessed on 16 February 2017).
- Chumpae Rice Research Center. Tubtim Chumpae Rice. 2015. Available online: http://www.thairice.org/html/doc-dl/brochure-tuptimpare.pdf (accessed on 18 February 2017).
- Suwannawong, S. Plant Nutrition Analysis; Kasetsart University: Bangkok, Thailand, 2001; p. 62. [Google Scholar]
- Zarcinas, B.A.; Cartwright, B.; Spouncer, L.R. Nitric acid digestion and multi-element analysis of plant material by inductively coupled plasma spectrometry. Commun. Soil Sci. Plant Anal. 1987, 181, 31–146. [Google Scholar] [CrossRef]
- Piepho, H.P.; Büchse, A.; Richter, C. A mixed modelling approach for randomized experiments with repeated measures. J. Agron. Crop Sci. 2004, 190, 230–247. [Google Scholar] [CrossRef]
- Khoshgoftarmanesh, A.H.; Schulin, R.; Chaney, R.L.; Daneshbakhsh, B.; Afyuni, M. Micronutrient efficient genotypes for crop yield and nutritional quality in sustainable agriculture. A review. Agron. Sustain. Dev. 2009, 30, 83–107. [Google Scholar] [CrossRef] [Green Version]
- Fageria, N.K. The Use of Nutrients in Crop Plants; CRC Press: Boca Raton, FL, USA, 2009. [Google Scholar]
- Borg, M.; Brownfield, L.; Twell, D. Male gametophyte development: A molecular perspective. J. Exp. Bot. 2009, 60, 1465–1478. [Google Scholar] [CrossRef] [Green Version]
- Kobayashi, H.; Sakurai, T.; Imai, M.; Takahashi, N.; Fukuda, A.; Yayoi, O. Contribution of intragenic DNA methylation in mouse gametic DNA methylomes to establish oocyte-specific heritable marks. PLoS Genet. 2012, 8, e1002440. [Google Scholar] [CrossRef] [Green Version]
- Kamali, B.; Chandra Sekaran, N.; Kalaiselvi, T.; Chitdeshwari, T. Exogenouse foliar application of FeSO4 on enrichment of iron in rice grain and yield. J. Pharmacogn. Phytochem. 2020, 9, 3344–3348. [Google Scholar]
- Impa, S.M.; Morete, M.J.; Ismail, A.M.; Schulin, R.; Johnson-Beebout, S.E. Zn uptake, translocation, and grain Zn loading in rice (Oryza sativa L.) genotypes selected for Zn deficiency tolerance and high grain Zn. J. Exp. Bot. 2013, 64, 2739–2751. [Google Scholar] [CrossRef] [PubMed]
- Johnson-Beebout, S.E.; Lauren, J.G.; Duxbury, J.M. Immobilization of zinc fertilizer in flooded soils monitored by adapted DTPA soil test. Commun. Soil Sci. Plant Anal. 2009, 40, 1842–1861. [Google Scholar] [CrossRef]
- Prom-U.-Thai, C.; Rashid, A.; Ram, H.; Zou, C.; Guilherme, L.R.G.; Corguinha, A.P.B.; Guo, S.; Kaur, C.; Naeem, A.; Yamuangmorn, S.; et al. Simultaneous biofortification of rice with zinc, iodine, iron and selenium through foliar treatment of a micronutrient cocktail in five countries. Front. Plant Sci. 2020, 11, 589835. [Google Scholar]
- Rout, G.R.; Sahoo, S. Role of iron in plant growth and metabolism. Agric. Sci. 2015, 3, 1–24. [Google Scholar] [CrossRef] [Green Version]
- Babaeian, M. Efficacy of different iron, zinc and magnesium fertilizers on yield and yield components of barley. Afr. J. Microbiol. Res. 2012, 6, 5754–5756. [Google Scholar]
- Saenchai, C.; Prom-u-thai, C.; Jamjod, S.; Dell, B.; Rerkasem, B. Genotypic variation in milling depression of iron and zinc concentration in rice grain. Plant Soil 2012, 361, 271–278. [Google Scholar] [CrossRef]
- Ponnamperuma, F.N.; Castro, R.U. Varietal Differences in Resistance to Adverse Soil Conditions; International Rice Research Institute, Rice Breeding: Los Baños, Philippines, 1972; pp. 677–684. [Google Scholar]
- Annual Report for 1970; International Rice Research Institute (IRRI): Laguna, Philippines, 1971; p. 265.
- De Datta, S.K. Principles and Practices of Rice Production; John Wiley and Sons, Inc.: New York, NY, USA, 1981; p. 353. [Google Scholar]
- Dobermann, A.; Fairhurst, T.H. Rice Nutrient Disorders and Nutrient Management; Oxford Graphic Printers Pte Ltd.: Singapore, 2000; p. 191. [Google Scholar]
- Saenchai, C.; Prom-u-thai, C.T.; Jamjod, S.; Dell, B.; Rerkasem, B. Iron and zinc partitioning in rice plant during grain filling. Khon Kaen Agr. J. 2015, 43, 67–78. (in Thai). [Google Scholar]
- Yadav, G.S.; Shivay, Y.S.; Kumar, D.; Babu, S. Enhancing iron density and uptake in grain and straw of aerobic rice through mulching and rhizo-foliar fertilization of iron. Glob. Afr. J. Agric. Res. 2013, 8, 5447–5454. [Google Scholar]
- Wang, Q.; Chen, M.; Hao, Q.; Zeng, H.; He, Y. Research and progress on the mechanism of iron transfer and accumulation in rice grains. Plants 2021, 10, 2610. [Google Scholar] [CrossRef] [PubMed]
- Sharma, A.; Shankhdhar, D.; Shankhdhar, S.C. Enhanching grain iron content of rice by the application of plant growth promoting rhizobacteria. Plant Soil Environ. 2013, 59, 89–94. [Google Scholar] [CrossRef]
Figure 1.
The interactions of iron fertilizer application methods, rice cultivars and years on iron contents (a) and the interactions of iron fertilizer application methods with rice cultivars on shoot iron uptakes at 90 days after planting (b); means with the same letter are not significantly different by Turkey HSD test.
Figure 1.
The interactions of iron fertilizer application methods, rice cultivars and years on iron contents (a) and the interactions of iron fertilizer application methods with rice cultivars on shoot iron uptakes at 90 days after planting (b); means with the same letter are not significantly different by Turkey HSD test.
Figure 2.
Relationship between brown rice grains’ iron concentrations and grain yields of three rice cultivars of each cropping year (2017 (a); 2018 (b)).
Figure 2.
Relationship between brown rice grains’ iron concentrations and grain yields of three rice cultivars of each cropping year (2017 (a); 2018 (b)).
Figure 3.
The correlations of grain Fe concentrations and grain yields: Riceberry (a), Chainat1 (b) and Tubtim Chumpae (c) in 2017; Riceberry (d), Chainat1 (e) and Tubtim Chumpae (f) in 2018; ns and ** = not significant and significant different at 0.01 level, respectively.
Figure 3.
The correlations of grain Fe concentrations and grain yields: Riceberry (a), Chainat1 (b) and Tubtim Chumpae (c) in 2017; Riceberry (d), Chainat1 (e) and Tubtim Chumpae (f) in 2018; ns and ** = not significant and significant different at 0.01 level, respectively.
Table 1.
Weather data during the growth periods of the experimental site in 2017 and 2018.
| Month | Rainfall | Temperature (°C) | Relative Humidity | Sunlight | ||
|---|---|---|---|---|---|---|
| (mm) | Minimum | Maximum | Average | (%) | (h day−1) | |
| 2017 | ||||||
| January | 1.2 | 20.3 | 30.8 | 25.6 | 63 | 5.9 |
| February | 4.6 | 19.1 | 32.3 | 25.7 | 56 | 8.3 |
| March | 81.4 | 23.1 | 34.7 | 28.9 | 64 | 7.4 |
| April | 37.0 | 24.7 | 35.6 | 30.2 | 64 | 7.7 |
| May | 188.0 | 24.8 | 34.1 | 29.5 | 76 | 5.5 |
| Mean | 62.4 | 22.4 | 33.5 | 28.0 | 64.6 | 7.0 |
| 2018 | ||||||
| January | 1.0 | 19.3 | 30.5 | 24.9 | 67 | 6.2 |
| February | 5.4 | 19.3 | 30.7 | 25 | 63 | 7.1 |
| March | 28.0 | 22.5 | 33.6 | 28.05 | 62 | 7.8 |
| April | 206.2 | 23.7 | 34.1 | 28.9 | 66 | 7.3 |
| May | 163.1 | 24.4 | 34.1 | 29.25 | 77 | 6.9 |
| Mean | 80.7 | 21.8 | 32.6 | 27.2 | 67.0 | 7.1 |
Table 2.
Soil physico-chemical properties of the experimental site in 2017 and 2018.
| Parameters | 2017 | 2018 | Analysis Method |
|---|---|---|---|
| pH (1:1 soil:water) | 7.31 | 7.47 | pH meter |
| Total N (%) | 0.035 | 0.031 | Kjeldahl nitrogen method |
| Available P (mg/kg) | 5.28 | 8.83 | Bray II |
| Exchangeable K (mg/kg) | 92.78 | 83.01 | Flame photometer |
| Exchangeable Ca (mg/kg) | 475 | 544 | Flame photometer |
| Available Fe (mg/kg) | 29.39 | 63.14 | Atomic absorption spectrophotometer |
| Organic matter (%) | 0.629 | 0.578 | Wet oxidation |
| CEC (c mol (+)/kg) | 4.62 | 4.82 | Ammonium acetate extract |
| Textural class | Sandy loam | Sandy loam | Hydrometer method |
| Sand (%) | 73.57 | 73.64 | Hydrometer method |
| Silt (%) | 15.14 | 16.14 | Hydrometer method |
| Clay (%) | 11.29 | 10.22 | Hydrometer method |
Table 3.
Effects of iron fertilizer application methods on plant heights and tiller numbers of three rice cultivars at 30, 60 and 90 days after transplanting (DAT) for two cropping years.
Table 3.
Effects of iron fertilizer application methods on plant heights and tiller numbers of three rice cultivars at 30, 60 and 90 days after transplanting (DAT) for two cropping years.
| Treatment | 30 DAT | 60 DAT | 90 DAT | |||
|---|---|---|---|---|---|---|
| Plant Height (cm) | Tiller (No./Hill) | Plant Height (cm) | Tiller (No./Hill) | Plant height (cm) | Tiller (No./Hill) | |
| Year (Y) | ||||||
| 2017 | 45.47 b | 10.42 | 69.41 b | 14.92 | 90.59 | 16.95 |
| 2018 | 47.62 a | 11.27 | 71.08 a | 14.61 | 90.00 | 16.35 |
| Method of application (M) | ||||||
| Control | 45.92 | 11.10 | 70.02 | 15.05 | 90.68 | 17.42 |
| Soil | 46.99 | 10.67 | 70.42 | 14.78 | 92.21 | 16.98 |
| Foliar | 46.76 | 11.00 | 70.19 | 14.08 | 88.47 | 16.19 |
| Soil + foliar | 46.52 | 10.63 | 70.35 | 15.16 | 89.83 | 17.20 |
| Cultivar (C) | ||||||
| Chainat1 | 49.67 a | 12.28 a | 74.82 a | 12.96 a | 96.38 a | 19.81 a |
| Riceberry | 42.86 c | 10.85 b | 63.10 c | 10.56 b | 88.64 b | 16.78 b |
| Tubtim Chumpae | 47.12 b | 9.42 c | 72.82 b | 8.78 c | 85.87 b | 16.87 b |
| F-test | ||||||
| Y | ** | ns | ** | ns | ns | ns |
| M | ns | ns | ns | ns | ns | ns |
| C | ** | ** | ** | ** | ** | * |
| Y × M | ns | ns | ns | ns | ns | ns |
| Y × C | ns | ns | ns | ns | ns | ns |
| M × C | ns | ns | ns | ns | ns | ns |
| Y × M × C | ns | ns | ns | ns | ns | ns |
*, ** and ns = significant at 0.05 level, 0.01 level and not significant, respectively. Means in the same column with different letters are significantly different at p ≤ 0.05, as determined by Tukey HSD.
Table 4.
Effects of iron fertilizer application methods on yields and grain iron contents of three rice cultivars at harvest for two cropping years.
Table 4.
Effects of iron fertilizer application methods on yields and grain iron contents of three rice cultivars at harvest for two cropping years.
| Treatment | Panicle No. (No./Hill) | Grain (No./Panicle) | 1000 Grain Weight (g) | Filled Grain (%) | Grain Yield (kg/ha) |
|---|---|---|---|---|---|
| Year (Y) | |||||
| 2017 | 13.02 | 129.73 | 25.82 b | 92.66 b | 3104.0 b |
| 2018 | 13.07 | 120.44 | 30.27 a | 93.61 a | 3869.1 a |
| Method of application (M) | |||||
| Control | 12.34 | 120.85 | 27.56 | 93.14 | 3335.1 |
| Soil | 13.09 | 127.52 | 28.62 | 92.58 | 3619.5 |
| Foliar | 13.45 | 125.24 | 28.08 | 94.62 | 3436.5 |
| Soil + foliar | 13.30 | 126.73 | 27.90 | 93.92 | 3555.2 |
| Cultivar (C) | |||||
| Chainat1 | 13.79 a | 127.62 a | 31.20 a | 92.20 b | 3923.5 a |
| Riceberry | 12.65 b | 134.84 a | 28.11 b | 95.44 a | 3370.2 b |
| Tubtim Chumpae | 12.69 ab | 112.79 b | 24.81 c | 91.77 b | 3165.9 b |
| F-test | |||||
| Y | ns | ns | ** | * | ** |
| M | ns | ns | ns | ns | ns |
| C | ** | ** | ** | ** | ** |
| Y × M | ns | ns | ns | ns | ns |
| Y × C | ns | ns | ns | ns | ns |
| M × C | ns | ns | ns | ns | ns |
| Y × M × C | ns | ns | ns | ns | ns |
*, ** and ns = significant at 0.05 level, 0.01 level and not significant, respectively. Means in the same column with different letters are significantly different at p ≤ 0.05, as determined by Tukey HSD.
Table 5.
Effects of iron fertilizer application methods on grain iron contents at harvest and shoot iron uptakes at 90 days after transplanting of three rice cultivars for two cropping years.
Table 5.
Effects of iron fertilizer application methods on grain iron contents at harvest and shoot iron uptakes at 90 days after transplanting of three rice cultivars for two cropping years.
| Treatment | Grain Iron Content (Fe g/ha) | Shoot Iron Uptake (Fe g/ha) |
|---|---|---|
| Year (Y) | ||
| 2017 | 71.86 b | 32.28 b |
| 2018 | 90.27 a | 68.67 a |
| Method of application (M) | ||
| Control | 60.20 c | 42.18 c |
| Soil | 86.52 ab | 52.42 b |
| Foliar | 82.54 b | 52.31 b |
| Soil + foliar | 94.99 a | 54.99 a |
| Cultivar (C) | ||
| Riceberry | 77.49 b | 50.34 b |
| Chainat1 | 91.75 a | 51.81 a |
| Tubtim Chumpae | 73.95 b | 49.27 b |
| F-test | ||
| Y | ** | ** |
| M | ** | ** |
| C | ** | ** |
| Y × M | ns | ns |
| Y × C | ns | ns |
| M × C | ns | ** |
| Y × M × C | ** | ns |
** and ns = significant at 0.01 level and not significant, respectively. Means in the same column with different letters are significantly different at p ≤ 0.05, as determined by Tukey HSD.
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |
© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
MDPI and ACS Style
Butsai, W.; Kaewpradit, W.; Harrell, D.L.; Polthanee, A. Effect of Iron Application on Rice Plants in Improving Grain Nutritional Quality in Northeastern of Thailand. Sustainability 2022, 14, 15756. https://doi.org/10.3390/su142315756
AMA Style
Butsai W, Kaewpradit W, Harrell DL, Polthanee A. Effect of Iron Application on Rice Plants in Improving Grain Nutritional Quality in Northeastern of Thailand. Sustainability. 2022; 14(23):15756. https://doi.org/10.3390/su142315756
Chicago/Turabian StyleButsai, Wipada, Wanwipa Kaewpradit, Dustin L. Harrell, and Anan Polthanee. 2022. "Effect of Iron Application on Rice Plants in Improving Grain Nutritional Quality in Northeastern of Thailand" Sustainability 14, no. 23: 15756. https://doi.org/10.3390/su142315756
Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.
