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Seed germination is the first developmental phase in a plant's life cycle that is followed by emergence from the soil, successful seedling and establishment, and fruitful yield. Seed germination is influenced by multiple environmental factors such as temperature, moisture, and aeration. An in vitro experiment was conducted to quantify the effects of temperatures ranging from 10[degrees]C to 42.5[degrees]C on germination properties of corn, cotton, and soybean seeds. Cumulative seed germination was recorded over time, was fitted with a three-parameter sigmoidal function to calculate maximum seed germination and seed germination rate. Maximum seed germination was significantly influenced by the interaction of temperature and species. The seed germination rate was further analyzed as a function of temperature by fitting bilinear and quadratic functions to the data. Cardinal temperatures (minimum, optimum, and maximum) were estimated from that regression analysis. Corn displayed the highest optimal temperature of 34.6[degrees]C. Cotton showed higher minimum and maximum cardinal temperatures than both corn and soybean. The cardinal temperatures and functional relationships between seed germination rate and temperature determined in this experiment will be useful to update crop simulation models and assess the best planting dates for rapid, successful germination based on environmental conditions. Keywords: Cardinal temperatures, corn, cotton, soybean, maximum seed germination, optimum temperature, seed germination models, seed germination rate Abbreviations: MSG, maximum seed germination; SGR, seed germination rate, INTRODUCTION In Mississippi, soybean [Glycine max (L.) Merr.], cotton (Gossypium hirsutum L.), and corn (Zea mays L.) are three of the most widely grown agronomically important crop species. In 2018, [...]

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]