Mutants of Gossypium hirsutum: Effect on Pink Bollworm in Arizona12

Abstract

Several mutants in upland cotton, Gossypium hirsutum L., sustained less seed damage from pink bollworm (PBW), Pectinophora gossypiella (Saunders), than the check cultivars ‘Deltapine 16’, ‘Deltapine 61’, ‘Stoneville 7A’, and ‘Stoneville 213’. These mutants were as follows: glabrous, early-maturing, high-terpenoid (gossypol and related compounds), Okra-leaf and Super Okra-leaf. Earlier studies had shown that glabrous, nectariless, glabrous-nectariless, and highly pubescent mutants, and an upland cotton of complex background (AET-5), had sustained less seed damage than the check cultivars. Cottons having as much as or more seed damage than checks were Red plant, late-maturing, glandless, and frego-bract, and also strains carrying exotic cytoplasms from 6 other Gossypium spp. Practically all the cottons tested that showed resistance to PBW were earlier maturing and yielded less lint than the check cultivars. Exceptions were: ‘Westburn M’, slightly earlier, with significantly lower seed damage, and with a slightly lower lint yield the 1st season but a significantly higher yield the 2nd season; ‘DES 56’, significantly earlier, with slightly lower seed damage, and with a comparable lint yield the 1st season, and a significantly higher lint yield the 2nd season; and Stoneville 7A Okra-leaf, significantly earlier, with significantly less seed damage, and with slightly lower lint yields. No single character reduced seed damage sufficiently to be adequate for PBW control.