Kernel Development in Wheat

Abstract

Kernel weight and test weight are two important components of wheat (Triticum aestivum L.) yield and quality. However, little research has been done in North Carolina to quantify kernel development in response to environmental and management conditions. Therefore, this study was conducted to examine how factors such as plant density, light interception, fungicide, and nitrogen influence kernel development during the grain filling period and its impact on grain yield. Field research was conducted at seven site‐years in North Carolina from 2011 to 2014 to investigate these factors. Six treatments were imposed to examine their influence on kernel development: an untreated control, a fungicide treatment, a nitrogen treatment, a shaded treatment, a low seeding rate, and a high seeding rate. The shaded treatment had the lowest rate of grain fill at each location (2.13 × 10−6 oz growing degree day [GDD]−1); however, there was no consistent difference among the remaining treatments. The shade treatment caused a low rate of grain fill, which resulted in the shade treatment having the lowest yield across all locations (78 bu acre−1). The impact of the shade indicates the importance of proper light interception during the grain filling period. When light interception or green leaf area is reduced, both the rate of grain fill and the yield are severely reduced. While a fungicide application at Growth Stage 70 did not show a significant increase in the rate of grain fill or yield, it may be beneficial when there is intense disease pressure that will inhibit light interception during the grain filling period.