The relationship between commercial cotton cultivars with varying Meloidogyne incognita resistance genes and yield

Abstract

0.05) than yield for susceptible cultivars (1,243 kg lint/ha). If the older resistant cultivars from Deltapine and PhytoGen (those with only Roundup Ready® herbicide technology) were removed from the analysis, then HR-PHY yields increased by 133 kg of lint/ha to 1,460 kg lint/ha and NR-DP yields remained approximately unchanged (1,227 kg lint/ha). Newer HR-PHY had much improved yield over the first HR-PHY cultivars. Newer HR-PHY averaged 17% higher yield than the susceptible group. LOG10 (M. incognita eggs/500 cm3 soil + 1) were highest for the susceptible cultivars (3.2), followed by PR-FM/ST (2.6), NR-DP (2.4), PR-PHY (2.1), and lowest with HR-PHY (1.4). The newer HR-PHY cultivars (those with ENLIST® herbicide technology) combine excellent yields (17% higher than susceptible cultivars) with high (96%) suppression of M. incognita.