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Cotton is a pivotal global commodity underscored by its economic value and widespread use. In the face of climate change, breeding resilient cultivars for variable environmental conditions becomes increasingly essential. However, the process of phenotyping, crucial to breeding programs, is often viewed as a bottleneck due to the inefficiency of traditional, low-throughput methods. To address this limitation, this study utilizes hyperspectral remote sensing, a promising tool for assessing crucial crop traits across forty cotton varieties. The results from this study demonstrated the effectiveness of four vegetation indices (VIs) in evaluating these varieties for water-use efficiency (WUE). The prediction accuracy for WUE through VIs such as the simple ratio water index (SRWI) and normalized difference water index (NDWI) was higher (up to R2 = 0.66), enabling better detection of phenotypic variations (p < 0.05) among the varieties compared to physiological-related traits (from R2 = 0.21 to R2 = 0.42), with high repeatability and a low RMSE. These VIs also showed high Pearson correlations with WUE (up to r = 0.81) and yield-related traits (up to r = 0.63). We also selected high-performing varieties based on the VIs, WUE, and fiber quality traits. This study demonstrated that the hyperspectral-based proximal sensing approach helps rapidly assess the in-season performance of varieties for imperative traits and aids in precise breeding decisions. [ABSTRACT FROM AUTHOR]

Potassium (K) deficiency in corn is an emerging concern, especially when the crop is exposed to stress conditions. The insufficient replenishment of K in soil heightens the severity. A good K management requires adequate knowledge of its effect on plant growth and physiology. A sunlit growth chamber study was conducted under five levels of potassium concentrations, 100% (control; 193 ppm), 40%, 20%, 5%, and 0%, using modified Hoagland's nutrient solution applied at first leaf stage and continued until tasseling. The plant growth and development were monitored at different growth stages. Physiological parameters were measured at the tasseling stage. Significant differences (p < 0.05 to 0.001) in plant growth and physiological parameters were recorded in response to potassium rates. The 0% K treatment reduced the leaf K content and addition of leaf area day−1 by 85% and 8%, respectively, compared to the control. The rate of total biomass accumulation reduced to 5.4 g day−1 under 0% K compared to 7.7 g day−1 under the control. The root-to-shoot ratio increased to 0.33 at 5% K compared to 0.16 at the control treatment. The photosynthetic rate was reduced by 30% and 35% under 5% and 0% potassium concentrations, respectively, compared to the control. The 0% K deficiency decreased the stomatal conductance by 60% over control, lowering the internal CO2 level and transpiration. Linear and quadratic relationships were observed between leaf K content and electron transport rate (R2 = 0.98) and transpiration rate (R2 = 0.96), respectively. The functional relationships generated from this study will help improve corn models for field applications. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV)-B radiation is considered one of the major detrimental rays coming from the Sun. UV-B radiation has a harmful impact on plant growth and development. The effect of UV-B radiation was studied on 64 rice (Oryza sativa L.) genotypes during the vegetative season. An equal number of genotypes from the japonica (50%) and indica (50%) subspecies were phenotyped using the Soil-Plant-Atmosphere-Research (SPAR) units. The 10 kJ UV-B was imposed 12 days after planting (DAP) and continued for three weeks (21 d). Based on the combined ultraviolet-B radiation response index (CUVBRI) for each genotype, the 64 rice genotypes were classified into sensitive, moderately sensitive, moderately tolerant, and tolerant. Various shoot traits, such as plant height, tiller, and leaf numbers, were measured. We also studied critical root phenological traits like root volume, diameter, tips, and forks. Out of all the studied shoot traits, leaf area showed maximum reduction for both indica (54%) and japonica (48%). Among the root traits, root length decreased by negligible (1%) for indica as compared to japonica (5%), while root crossing and forks showed a maximum decline for japonica (37 and 42%), respectively. This study is timely, meaningful, and required because it will help breeders select a tolerant or sensitive rice line for better yield and production under abiotic stresses. [ABSTRACT FROM AUTHOR]

Potential global climate change-related impacts on crop production have emerged as a major research priority and societal concern during the past decade. Future changes, natural and human-induced, projected in the climate have implications for regional and global crop production. The simultaneous occurrence of several abiotic stresses instead of stress conditions is most detrimental to crops, and this has been long known by farmers and breeders. The green leafy vegetables of the Brassicaceae family have especially gained attention due to their many health benefits. However, little information is available about abiotic stress's effects on Brassica vegetables' growth and development. An experiment was conducted on two Brassica species: B. oleracea L. var. acephala WINTERBOR F1 (hybrid kale) and B. juncea var. GREEN WAVE OG (mustard greens). Seven treatments were imposed on the two brassica species in soil–plant–atmosphere–research (SPAR) units under optimum moisture and nutrient conditions, including a control treatment (optimal temperature and UV-B conditions at ambient CO2 levels), and six treatments where stresses were elevated: CO2, UV-B, temperature (T), CO2+UV-B, CO2+T, and CO2+UV-B+T. Above- and below-ground growth parameters were assessed at 26 d after sowing. Several shoot and root morphological and developmental traits were evaluated under all the treatments. The measured growth and development traits declined significantly under individual stresses and under the interaction of these stresses in both the species, except under elevated CO2 treatment. All the traits showed maximum reductions under high IV-B levels in both species. Leaf area showed 78% and 72% reductions, and stem dry weight decreased by 73% and 81% in kale and mustard, respectively, under high UV-B levels. The increased CO2 concentrations alleviated some deleterious impacts of high temperature and UV-B stresses. The results of our current study will improve our understanding of the adverse effects of environmental stresses on the early-season growth and development of two Brassica species. [ABSTRACT FROM AUTHOR]

Cotton quality is as crucial as cotton quantity. Despite considerable efforts to enhance cotton yield, there has been limited focus on maximizing fiber quality. The temperature experienced from flowering to boll opening becomes the critical factor affecting fiber quality when cotton is cultivated under optimum water and nutrient conditions. This depends on the planting date for a specific location and cultivar. Therefore, fiber quality can be improved by optimizing the planting date for a specific geographic location and cultivar. The study aims to develop a methodology for optimizing planting dates to maximize fiber quality, taking into account location-specific weather and cultivar details. A methodology is developed and demonstrated for the cotton belt in the USA. The methodology accounts for temperature, planting intervals, cotton varieties (early, mid, and late-season), and four major fiber quality indicators (fiber length, strength, micronaire, and uniformity). Based on the average of the last 15 years of weather data and different cotton cultivars, spatial maps depicting the best planting dates and associated fiber quality are analyzed for 765 cotton-growing counties in the USA. The study also explores variability in the optimum planting date and fiber quality with climate change in these counties. Results indicate that planting cotton at the optimum planting date can improve all fiber quality features. Fiber length can range from medium (25–29 mm) to long (30–34.5 mm), fiber strength from strong (29–30 g/tex) to very strong (>31 g/tex), micronaire from the discount range (≤3.4 and ≥5.0) to the base range (3.5–3.6 and 4.3–4.9), and uniformity can be high (>85). Applying the methodology with consideration of future climate projections shows a 19 % decline in micronaire - the most affected trait, followed by 8.4 % and 1.6 % decreases in length and uniformity, respectively. In contrast, fiber strength is expected to increase by 5 % in the future. Results indicate that optimizing the planting date with the developed methodology can enhance fiber quality. Additionally, the methodology can predict variations in fiber quality due to future climatic conditions. The developed methodology can be valuable for farmers and growers seeking to enhance fiber quality. It is standard and applicable to any location and cultivar. A similar approach can be adopted for other locations and crops, such as soybeans, rice, and wheat, to optimize their quality. [Display omitted] • Novel methodology for cotton quality optimization through planting date selection. • Optimal planting dates for cotton across the USA cotton belt at the county level. • Variability in fiber quality and optimum planning dates with climate change. • In the future, micronaire, uniformity, and length show a decrease; strength shows an increase. • A standard methodology that is adaptable to other crops. [ABSTRACT FROM AUTHOR]