Phenotypic and Genetic Evaluation of LONREN Germplasm

The reniform nematode is an economically serious and geographically expanding cotton pest. There are no released sources of high-level resistance to the reniform nematode except the LONREN lines. These lines resulted from joint project of Cotton Incorporated, USDA-ARS, and Texas Agri-Life that successfully introgressed virtual immunity to reniform nematode from Gossypium longicalyx into G. hirsutum by means of triple-species hybrids and back crossing. The LONREN lines are highly resistant to reniform nematode, but may exhibit mild to severe stunting in the presence of high populations of this pest. Alien genes introduced by the wide crosses may be conferring disease and/or herbicide sensitivity. Our objective is to alleviate the effects of these hypothesized susceptibilities by generating robust recombinants.