Early season vigor in peanuts is dependent on leaf area responses to temperature

Abstract

AbstractWhole‐crop growth at early season in peanuts (Arachis hypogaea L.) can be influenced by genotype, management, and environmental conditions such as soil and air temperatures. To determine the effect of different planting conditions on peanut growth and vigor in the early season, modern peanut cultivars were planted in two growing seasons on 17 April, 10 May, and 5 June in 2017 and 25 April, 14 May, and 11 June in 2018 season, targeted to generate differences in temperature during early growth. Field measurements included emergence assessments and destructive harvest at 21 and 35 days after planting to quantify plant density, height, leaf area, and dry matter accumulation. Additionally, crop growth indices were calculated. Results showed that planting date and cultivar significantly affected plant growth parameters and derived growth indices. Planting in June resulted in greater growth parameters, crop growth rate, and leaf area index compared to April and May for both seasons. However, net assimilation rate was highest for May in 2017 and for June in 2018. Comparing cultivars, Georgia‐06G and TifNV‐high O/L were more vigorous than Georgia‐14N. Average soil and air temperatures were the highest with June planting and produced more vigorous seedling growth and greater crop growth rates than planting in April and May. Furthermore, our results suggest that the differences in the early season crop growth of modern peanut cultivars were more strongly and closely associated with leaf area development rather than specific leaf activity, that is, net assimilation rate of the canopy.