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Acetolactate synthase (ALS) inhibitor herbicides are among widely marketed herbicide chemistries that act both against grass and broad-leaved weeds. Sorghum (Sorghum bicolor (L.) Moench) variants carrying resistance to ALS inhibitor herbicides were developed as a post-emergence weed control solution in sorghum. However, some ALS-resistant lines exhibit noticeable interveinal chlorosis at seedling stage, leading to reduced vigor. Although the plants eventually recover at an advanced growth stage, this may be a source of concern for growers and can undermine adoption of the technology. This study was initiated to identify mechanisms related to the manifestation of this phenotype. Two ALS-resistant genotypes, one displaying a yellow phenotype and the other a normal green phenotype, were cultivated, and tissue samples were collected at four time intervals, with the final sampling occurring after the genotypes had fully re-greened. RNA was extracted from the tissue samples and subjected to RNA-Seq analysis. Differential gene expression analysis was carried out using DESeq2, and a selected set of genes were confirmed via qRT-PCR. Gene Ontology enrichment and SorghumCyc pathway analysis uncovered notable regulatory changes in genes associated with chloroplasts, plant defense responses, and hormonal networks in the yellow genotypes. The pattern of gene expression strongly mimicked responses under abiotic stresses. In addition, the findings offer new insights into the potential for sorghum genotypes resistant to environmental stresses to also exhibit tolerance to a range of additional stresses. [ABSTRACT FROM AUTHOR]

Cold susceptibility is a concern when growing crops of tropical origin in temperate regions. Crops such as rice, corn, sorghum, and soybean are generally susceptible to chilling stress. From production standpoint, a crop's cold tolerance is particularly important when the general recommendation is to adopt earlier than currently practicing planting dates in the spring. Early planting is a potential route to increase soybean yield in the United States. Nonetheless, early planting is often not practically feasible due to low soil temperatures. Although some commercial varieties are cold‐tolerant, soybean is generally prone to cold stress. Soil temperatures below 10°C reduce germination and seedling vigour. Cold temperatures can also increase soybean vulnerability to soilborne seed/seedling diseases. Microorganisms are experimentally shown to alleviate cold stress in agriculturally important crops such as rice, wheat, tomato and grapes. Although microbial inoculants are available to augment soybean yields through enhanced nitrogen fixation, phosphorus solubilization and improved water/nutrient uptake, currently there are no commercially available inoculants to enhance soybean cold tolerance. Here we provide insights into the value of soybean rhizosphere microbiome analysis to identify microbial taxa that could potentially enhance soybean cold tolerance. Formulation of promising candidates into a seed treatment could contribute to early planting‐enabled soybean yield gains. [ABSTRACT FROM AUTHOR]

Sweet sorghum (Sorghum bicolor [L.] Moench) is a prospective bioethanol feedstock source. Four high‐biomass and sweet sorghum male lines and three grain sorghum female lines were intercrossed using Design II mating. Parents and hybrids were evaluated to (a) identify genetic sources to improve biofuel traits, and (b) determine the inheritance of biofuel and morpho‐agronomic traits. Total soluble sugars (TSS) per plant were determined using juice weight (JW) and Brix (°Bx). Plant height (PH), biomass (BM) and stalk diameter (SD) were also measured. Mean hybrid performance for PH, JW, TSS and BM was higher than the male parent means. Three male parents exhibited positive and significant general combining ability (GCA) for at least three traits. Among males, PI185672 showed the highest GCA for PH, °Bx and BM, while No. 08 exhibited the greatest GCA for JW and TSS. Most hybrids exhibited overdominance‐driven high‐parent heterosis for all traits except SD. Trait broad‐sense heritability ranged from 0.71 (BM) to 0.93 (PH). Results revealed that biofuel traits could be substantially improved through breeding, which will contribute to enhanced bioethanol production. [ABSTRACT FROM AUTHOR]