Crops, Volume 4, Issue 4 (December 2024) – 17 articles

The present study investigates the cryopreservation of embryonic axes from the peanut genotype ECU-12466, demonstrating a successful protocol involving a 1 h desiccation on silica gel followed by a 1 h cryoprotection with Plant Vitrificatin Solution 2 (PVS2). The average dimensions of the excised embryonic axes were 5.6 mm in length and 3.5 mm in width, with plumule lengths averaging 2.2 mm. Notably, germination rates for cryopreserved axes ranged from 71.4% to 85.7%, showing resilience to varying desiccation and PVS2 treatment times, particularly at 1 h. Shoot length was significantly enhanced by a 1 h PVS2 exposure, while longer durations resulted in phytotoxic effects. Rooting rates were higher for samples treated with shorter desiccation periods, with 54% rooting achieved at 1 h of PVS2 exposure, contrasting sharply with just 16% at 2 h. The moisture content of the embryonic axes remained stable between 9.3% and 9.5%, indicating no detrimental impact from the applied treatments. To evaluate the protocol’s broader applicability, five additional peanut genotypes (ECU-11401, ECU-11418, ECU-11448, ECU-11469, and ECU-11494) were tested. While cryopreserved samples demonstrated high germination rates of up to 95.4% after 15 days, the rooting success was significantly lower (25.2%) compared to the control group’s 90.9%. Following transplantation, the growth performance varied among genotypes, with a success rate of 93% for ECU-11494. Overall, this study elucidates the critical parameters for optimizing cryopreservation protocols in peanut embryonic axes, contributing to more effective long-term conservation strategies. Full article

Salinity is one of the major abiotic stresses that abate the yield of several crop species including rice. Several studies were conducted to identify quantitative trait loci (QTLs) for traits associated with salinity tolerance, mostly at the seedling stage of crop growth. However, the reproductive stage of development is highly sensitive to salt stress, and hence, better QTLs must be developed. QTLs have been identified in the present study for salt tolerance of the reproductive stage in rice using recombinant inbred lines (RILs). Thirty-day-old rice seedlings of 184 RILs derived from a cross between a salt sensitive RP Bio226 (indica), and a salt-tolerant Jarava (indica), were used to identify QTLs linked to salinity tolerance in moderate (field) and severe (pot) stress conditions. One hundred polymorphic simple sequence repeat (SSR) markers were used to construct a genetic linkage map that covered a 1349.4 cm genome with an average distance of 13.5 cm between loci. Eighteen new QTLs [logarithm of odds (LOD) 2.5 and above] were identified on chromosomes 1, 2, 6, 10, 11, and 12 using composite interval mapping with the phenotypic variation explained by QTL (PVE) as high as >42% with an LOD value of 5.2. qYLSt-12 with an LOD of 2.8 and a phenotypic variance (PV) of 6.4%, flanked by RM27940-RM27971, was identified for yield in moderate stress conditions. The qSTR-2 detected for salinity tolerance on chromosome 2 with 8.9% of the PV is the most significant finding of the present research. No QTL for salinity component traits has been reported in the region of RM110-RM423. The other salinity trait QTLs identified are qSN-11, qSN-12 for Na⁺ concentration with a total PVE% of 13.9 and qSNK-12.1, qSNK-12.2 for the Na⁺/K⁺ ratio showing a total of 26.7% of the PV. The QTLs for yield component traits viz. plant height, panicle number, panicle length, and biomass were also identified in the present study. Previous studies reported QTLs for salinity tolerance in rice on chromosome 1 but none of the QTLs in our study were on qSaltol or nearby position; therefore, Jarava conferred salinity tolerance in RILs due to novel QTLs. Fine mapping of these novel QTLs is suggested and could be helpful to enhance the level of tolerance through marker-assisted selection for the pyramiding of different QTLs in one background. Full article

Non-satisfactory bread-making quality in wheat, a Tajik staple, hampers food security in Tajikistan and calls for plant breeding efforts. Here, methods were searched for to study grain protein composition, which is of use for Tajik plant breeding to improve bread-making quality. Size-exclusion high-performance liquid chromatography (SE-HPLC) was used to determine protein composition in 22 wheat varieties and breeding lines grown in two locations, which were then compared with the specific protein composition evaluated using electrophoresis and previous results from Tajik breeding and farmer-grown wheat. As Tajik wheat generally showed a large variation in high-molecular-weight glutenin subunit (HMW-GS) composition, with several allelic variants in the same line, single-seed selection was required when using this methodology in breeding for improved bread-making quality, and such an evaluation willalso result in more homogenous lines for protein composition. SE-HPLC was found to be a suitable tool to evaluate protein composition in the current Tajik wheat material with a heterogeneous protein composition, which might be advantageous for adaptation to the local and future climate. However, more easy-to-handle and high-throughput methods, e.g., marker-assisted selection, could be preferable alternatives for studying protein composition in wheat and for use in breeding for increased bread-making quality to increase food security in Tajikistan. Full article

Anthracnose and grain mold are two of the most significant diseases of sorghum, a versatile crop that plays an important part in the daily lives of millions of inhabitants, especially in the drier tropical regions. The aim of this study was to determine the influence of four agronomic traits in selected sorghum germplasms on the two diseases using Spearman’s ρ test to identify significant pairwise correlations. Both anthracnose and grain mold scores were significantly and negatively correlated with seed weight and germination rate. The grain mold infection score also demonstrated negative correlations with plant height (Spearman ρ = −0.61 and p-value = <0.0001) and panicle length (Spearman ρ = −0.27 and p-value = 0.0022). In this investigation, principal component analysis and clustering variables analysis revealed that seed weight and germination rate exhibited a directional alignment, suggesting a positive association. Similarly, panicle length and plant height clustered together, suggesting a shared variation pattern. Additionally, a support vector machine and random forest models effectively predicted the germination rate based on the studied traits, highlighting the potential of machine learning in understanding complex trait relationships in sorghum. This work provides insights into the relationship between agronomic traits and disease resistance, thus contributing to sorghum improvement efforts. Full article

Broadening the genetic base of an elite breeding gene pool is one important goal in a successful long-term plant breeding program. This goal is largely achieved through the search for and introgression of exotic germplasm with adaptive traits. However, little is known about the genetic backgrounds of acquired exotic germplasm, as germplasm selection is mainly based on trait information. Here, we expanded an average pairwise dissimilarity (APD) analysis to samples with SNP genotypes associated with genes for specific characters of breeding interest. Specifically, we explored a gene-associated APD analysis in a genomic characterization of 2643 rice lines based on their published FASTQ data. Published contigs for cloned genes conditioning heat tolerance, cold tolerance, fertility, and seed size were downloaded as gene reference sequences for SNP calling, along with those SNP calls based on the rice reference genome and published indels. Totally, eight SNP or indel data sets were formed for each of three sample groups (All2643, Indica1789, and Japonica854). APD estimation was made for each of the 24 data sets. For each sample group, four novel sets of the 25 most genetically distinct rice lines, each for an assayed character, were identified. Further analyses of APD estimates also revealed some interesting APD properties. Four contig-based SNP data sets for four specific characters displayed similar APD frequency distributions and positive high correlations of APD estimates. Contig-based APD estimates were negatively correlated with genome-based APD estimates and nearly uncorrelated with indel-based APD estimates. These findings are significant for plant germplasm characterization and germplasm utilization in plant breeding. Full article

The fundamental key to increase photosynthetic efficiency of crop plants lies in optimizing the light energy use efficiency. In our study, we used tomato to evaluate the allocation of absorbed light energy in young and mature leaves, and to estimate if the extent of photoinhibition and photoprotection can be affected by the leaf age. A reduced efficiency of the oxygen-evolving complex, in young leaves compared to mature ones, resulted in a donor-side photoinhibition, as judged from the significantly lower Fv/Fm ratio, in young leaves. The detected increased ¹O₂ production in young leaves was probably due to a donor-side photoinhibition. The effective quantum yield of photosystem II (PSII) photochemistry (Φ_PSII), at low light intensity (LLI, 426 μmol photons m⁻² s⁻¹), was significantly lower in young compared to mature leaves. Moreover, the non-significant increase in non-photochemical energy loss in PSII (Φ_NPQ) could not counteract the decreased Φ_PSII, and as a result the non-regulated energy loss in PSII (Φ_NO) increased in young leaves, compared to mature ones. The significantly lower Φ_PSII in young leaves can be attributed to the increased reactive oxygen species (ROS) creation that diminished the efficiency of the open PSII reaction centers (Fv’/Fm’), but without having any impact on the fraction of the open reaction centers. The reduced excess excitation energy, in mature leaves compared to young ones, at LLI, also revealed an enhanced PSII efficiency of mature leaves. However, there was almost no difference in the light energy use efficiency between young and mature leaves at the high light intensity (HLI, 1000 μmol photons m⁻² s⁻¹). The ability of mature tomato leaves to constrain photoinhibition is possible related to an enhanced photosynthetic function and a better growth rate. We concluded that the light energy use efficiency in tomato leaves is influenced by both the leaf age and the light intensity. Furthermore, the degrees of photoinhibition and photoprotection are related to the leaf developmental stage. Full article

Allium species have great potential in the production of functional food via selenium biofortification. This review is devoted to the specificity of Allium plant biofortification with Se, including the genetic peculiarities, effect of the chemical form of the microelement, methods of supply, sulfur and AMF effects, and hormonal regulation. The biosynthesis of methylated Se amino acids and the beneficial effect of Se treatment on secondary metabolite accumulation and plant yield are discussed. Special attention is paid to the production of functional foods based on Allium plants enriched in different ways: bread with leek leaf powder, Allium microgreens and seedlings, and ‘Black garlic’ biofortified with Se. Further focus is provided to the high variability of Allium crop yield and quality under Se supply governed by genetic factors and environmental stresses, and to the need for plant growth technology optimization to obtain the predicted nutritional characteristics of the derived functional product with high anti-carcinogenic activity. Full article

The management of variety collections can be supported by integrating molecular data into Distinctness, Uniformity, and Stability (DUS) testing. DurdusTools is a genetic distance (GD) calculation tool that supports planning field trials in durum wheat. A commercially available single-nucleotide polymorphism (SNP) wheat microarray is used to profile varieties and candidate varieties. Their molecular profiles are stored in a database. SNP markers selected based on quality parameters are used to calculate the pairwise genetic distance (GD) between the varieties. Combining molecular and variety information creates a downloadable, user-friendly Excel-based output. The file shows the pairwise GD of the varieties most similar to the candidate variety of interest and selected variety information. After the first year of field trials, the DUS experts use the phenotypic assessment data together with the GD information to select genotypes to be grown in the field for side-by-side comparisons. The principles of DurdusTools allow for an easy integration of molecular data into DUS testing. Using the tool requires neither specific infrastructure nor molecular expert knowledge and was developed by its users for DUS testing purposes. This makes DurdusTools an easily accessible and user-friendly tool that supports variety selection for DUS field trials through an improved data basis. Full article

Insight into phototactic responses by herbivorous crop pests may be used to manipulate their vertical distribution in crop canopies. Here, we tested the hypothesis that the deployment of specific light sources elicits positive or negative phototactic responses and can be used to enhance performance of miticide applications. We characterized movement responses by two-spotted spider mites (Tetranychus urticae) (spider mites) to seven light sources [ambient (control), UV-C, UV-B, blue, red, white, and near-infrared (NIR)] under experimental conditions. Separate experiments were conducted with/without the presence of a shelter. An analytical approach based on linear regression coefficients (intercept and slope) from observations in ascending order was used. Linear regression coefficients from UV-B indicated significantly negative phototactic bio-response. We examined settlement of spider mites when exposed to 11 light source configurations and with adaxial leaf sides facing either upwards or downwards. This experiment revealed strong positive and negative phototactic bio-responses to blue light and UV-B light, respectively. As a validation experiment, soybean plants were experimentally infested with spider mites and subjected to one of the following three treatments: (1) no treatment (control), (2) miticide [pyrethrins and Beauveria bassiana (BotaniGard Maxx)] only, and (3) a combination of blue and UV-B for 10 min immediately prior to miticide application. Integration of miticide application with prior deployment of blue and UV-B lights significantly increased the performance of miticide application. Results from this study supported the hypothesis. As a pest management approach, the integration of blue light (to elicit positive phototactic response) and UV-B (to elicit negative phototactic response) is believed to be of particular relevance to organic crop producers and/or to producers of crops for which limited numbers of miticides are registered. Full article

Nigella sativa L., which is commonly referred to as black cumin, is a globally recognized plant for the nutraceutical and pharmaceutical values of its seed oil. While numerous studies have investigated Nigella oil, there is a scarcity of information regarding the variation of key phytoconstituents in Nigella oil from diverse seed sources. It is also unclear whether the variation in phytoconstituents across different seed sources translates to variations in their respective oils, which is important for understanding their health benefits. Additionally, there is a gap in information on how specific phytochemicals transfer from seed to oil during the oil pressing. Therefore, this study investigated Nigella sourced from different genotypes and agricultural practices (planting densities and sowing times) to determine total phenolic content (TPC), antioxidant capacity (FRAP and CUPRAC), thymoquinone (TQ), and fatty acid composition. The results showed significant variation of TPC (87.4–144.1 mg gallic acid equivalents (GAE)/100 g), FRAP (454.1–560.9 mg Trolox equivalents (TE)/100 g), CUPRAC (356.3–482.5 mg TE/100 g), TQ (1493.5–2268.4 mg TQ/100 g), saturated fatty acid (SFA) (65.9–83.7 mg/g), monounsaturated fatty acid (MUFA) (42.5–67.8 mg/g), and polyunsaturated fatty acid (PUFA) (266.1–383.4 mg/g) in the oil derived from the seeds of different genotypes and agricultural practices. The total transfer of TPC, FRAP, and CUPRAC into the screw-pressed oil was relatively low, contributing only 2.3–3.7%, 7.1–11.7%, and 1.5–2.3%, respectively, of their total value in the respective seed. However, the transfer of TQ, SFA, MUFA, and PUFA was observed to be comparatively higher, contributing 32.8–48.5%, 60.8–84.2%, 45.6–74.4%, and 43.1–69.4%, respectively, of their total value in the respective seed. There was no strong correlation observed among TPC, FRAP, CUPRAC, and TQ, and none of the fatty acids showed a strong correlation with these variables. Full article

Barley (Hordeum vulgare) is a major cereal grain grown in temperate climates globally and provides various nutrients in a peeled form after milling. However, milling causes changes in nutritional composition, including metabolites. Thus, a metabolomics study was conducted to monitor the changes in nutritional composition before and after the milling of Hordeum vulgare seeds (Saechalssal, Hinchalssal, and Yeongbaekchal) focusing on the development and application of new analytical methods for organic acids (OA) and amino acids (AA). Profiling analyses of OAs and AAs were performed using GC-MS/MS. This analytical method showed good linearity (r ≥ 0.995) with limit of detection (0.1 ng, 21.2 ng) and limit of quantitation (0.3 ng, 63.6 ng), respectively. Repeatability varied from 0.1 to 12.4 (% RSD) and accuracy varied from –12.3 to 14.8 (% RE), respectively. Altered levels of 36 metabolites (16 OAs, 20 AAs) were monitored post-milling and compared with pre-milling in the three Hordeum vulgare cultivars. Radar plots of OAs and AAs to corresponding mean levels of each pre-milling group in the three Hordeum vulgare cultivars were easily distinguished from those in each post-milling group. The pre-and post-milling groups of the three Hordeum vulgare cultivars were completely separated by partial least square discriminant analysis, and the lysine, cysteine, glutamic acid, asparagine, 4-hydroxyphenylacetic acid, and citric acid were significantly different. Therefore, this study will be useful for monitoring altered metabolites following milling and discrimination of varieties. Full article

While alfalfa (Medicago sativa) is widely used as forage because of its many positive attributes, there are concerns regarding bloat in grazing ruminants, but tannin-containing legumes, such as sainfoin (Onobrychis viciifolia), are non-bloating. Based on interest elsewhere for growing alfalfa–sainfoin mixtures to address bloat concerns, the objectives of a study conducted at Tucumcari, NM, USA, were to compare an alfalfa–sainfoin mixture to the respective monocultures for stand persistence and dry matter yield over three production years in three randomized complete blocks. The onset of drought limited irrigation water availability shortly after the study’s initiation, which limited sainfoin persistence to the second year after seeding. The resulting percentage decline in forage mass in June from year 1 to year 2 was alfalfa > alfalfa–sainfoin > sainfoin. That said, the alfalfa mass was considerably greater than the sainfoin mass, and the June mass of both monocultures was consistent with that in previous studies in the region when fully irrigated (5.57 vs. 2.00 Mg ha⁻¹ for monoculture alfalfa and sainfoin, respectively; p < 0.0004). Alfalfa persistence was greater than that of sainfoin after 3 years. Alfalfa–sainfoin mixtures may have value in the Southern High Plains of the USA and similar semiarid environments when fully irrigated. Additional studies should evaluate mixture seeding ratios and stand performance under fully irrigated conditions with sainfoin reseeding. Full article

This study explores organic hydroponic cultivation as a sustainable alternative to chemical fertilizers amid global supply challenges. With rising costs and the depletion of conventional nitrogen sources, organic liquid fertilizers are gaining attention for their microbial enrichment processes (MEP) that convert organic matter into plant-accessible nutrients. This experiment focuses on lettuce cultivation using two organic liquid fertilizers, Power Fish and POF vol. 2, in controlled environments. The results show that there are significant differences in plant growth parameters such as leaf number, fresh weight, chlorophyll content, and root length across different fertilizer treatments. Key findings include that effective management practices, including pH control and regular nutrient application, are crucial for maintaining microbial activity and optimizing nutrient uptake efficiency. Additionally, Bacillus sp. and Xanthomonas sp. were isolated from these fertilizers and dual-cultured with rot fungi, Pythium sp. and Fusarium sp. This dual cultivation demonstrated inhibitory activity against these pathogens, showcasing the potential of these microorganisms in promoting biofilm-mediated disease resistance in organic hydroponic systems. The study also emphasizes the phosphate solubilization capabilities of isolated bacteria, essential for sustainable nutrient cycling. Overall, organic hydroponic systems present a promising strategy for sustainable agriculture, reducing dependency on chemical inputs while enhancing crop productivity and resilience to environmental stressors. Full article

The fall armyworm, Spodoptera frugiperda, an invasive, polyphagous pest, causes significant damage to corn. The majority of insects rely on a broad range of digestive enzymes and an intricate detoxifying mechanism to consume chemically diverse host plants. The genetic variation in S. frugiperda was analyzed using cytochrome oxidase subunit I (COI) and triose phosphate isomerase (Tpi). In addition, a new attempt was made to determine the variation with respect to two detoxifying genes, viz., carboxylesterase and glutathione S-transferase. The highest genetic variation (3.03%) was found between the S. frugiperda populations of Tirupati and Delhi with respect to the Tpi gene and between the populations of Punjab and Hosur regarding COI (3.30%). The results for various genes revealed that populations of the fall armyworm were homogeneous, showing low genetic distance using COI, ranging from 0.40 to 3.30%, and, using Tpi, ranging from 0.43 to 3.03%. The variation in carboxylesterase and glutathione S-transferase ranged from 0.04 to 0.15% and from 0.01 to 0.02, respectively. Amino acid sequences were also produced using DNA sequences from several fall armyworm populations. Populations in Tirupati, Solapur, and Hyderabad shared 98.7% of their sequence with that in Delhi. Fall armyworm amino acid sequences showed 79.7 to 82.0% identity with S. exigua and 69.6 to 73.0% identity with S. litura. Our study provides vital information for understanding the genetic variation in the fall armyworm following its invasion of India. Full article

African yam bean (Sphenostylis stenocarpa Hochst, Ex. A. Rich. Harms) is an important grain legume in Sub-Saharan Africa because of its nutritional value and adaptability to various agroecological zones. To foster the varietal development of improved African yam bean (AYB) genotypes with economic traits, it is necessary to validate parental polymorphism for key markers in selecting progenies from crosses between desired parents. This study aims to analyze the genetic fidelity between parents and F1 progenies in African yam bean through putative cowpea simple sequence repeat (SSR) markers. Hence, a total of seventy-seven progenies were derived from four sets of biparental crossings using drought-susceptible (TSs-96, TSs-363, and TSs-274) and drought-tolerant (TSs-417, TSs-111, and TSs-78) AYB accessions. These were validated using 120 cowpea primers targeting SSRs under optimal PCR conditions, and the size of the PCR-amplified DNA fragments was checked using gel electrophoresis. Twenty primers exhibited polymorphism in the parental lines, while ten displayed higher levels of the same polymorphism. The average polymorphism level for the surveyed SSR markers was 0.36. Given these findings, our study demonstrates that cowpea SSR markers are a reliable method for the regular testing and clear identification of AYB crosses, indicating potential AYB improvements. Full article

Soil salinity significantly impacts crop productivity. In response, plant growth-promoting rhizobacteria (PGPR) offer an innovative and eco-friendly solution to mitigate salinity stress. However, research on PGPR’s effects on crop physiology under varying salinity levels is still emerging. This study evaluates the impact of five bacterial strains, isolated from compost, on the growth of maize (Zea mays) and tomato (Solanum lycopersicum) plants under different levels of salt stress. This study involved treating maize and tomato seeds with five bacterial strains, and then planting them in a greenhouse under varying salt stress conditions (43 mM, 86 mM, 172 mM, 207 mM NaCl) using a Randomized Complete Block Design. Results showed that bacterial inoculation improved plant growth under saline conditions. S2015-1, S2026-2, and S2027-2 (Bacillus cereus, Acinetobacter calcoaceticus, Bacillus subtilis) were particularly effective in promoting plant growth under salt stress, especially at ionic concentrations of 43 mM and 86 mM, leading to a substantial increase in fresh and dry weight, with strain S2015-1 boosting chlorophyll by 29% at 86 mM in both crops. These results highlight the potential of PGPR to enhance crop resilience and productivity under salinity stress, promoting climate-smart agricultural practices. Full article

Farmers today are using biochemical treatments to improve their crop yields. Commercialized organic biostimulants exist in the form of pyroligneous acid generated by burning agricultural waste products. During the 2023 growing season, we demonstrated that soil treatment with a commercial pyroligneous acid product, Coriphol™, manufactured by Corigin Solutions, Inc., stimulated plant growth and significantly improved yield with an optimal treatment dose of 2 gal. acre⁻¹. In the present work, we examined the effect of this treatment on soybean nutritional content using seed harvested from the 2023 season. Total mean seed protein content for untreated control plants was 32.26 ± 0.49% of dry mass and increased 10.8% to 35.64 ± 0.64% with treatment. This increase resulted in a net reduction in total free amino acid content, although levels of the essential dietary amino acid, lysine, were boosted 6-fold. Total lipid content was unaffected by treatment with mean levels of 21.61 ± 0.70% of dry mass noted. Treatment, however, reduced saturated fatty acid content by roughly 40%, and reduced the polyunsaturated content of linoleic acid in favor of the monounsaturated fatty acid, oleic acid. Finally, Coriphol™ treatment did not impact seed content of eight essential micronutrients including Na, Mg, K, Ca, Fe, Ni, Cu, and Mo, but did significantly boost Zn and Mn levels. Altogether, these results demonstrate that soil treatment with the growth stimulant Coriphol™ has the potential to improve the dietary nutritional value of soybean. Full article