Evaluation of Twelve Upland Cotton Genotypes for Resistance to Phymatotrichum omnivorum. C. G. Cook, Former Research Associate, Department of Soil and Crop Sciences, Texas Agricultural Experiment Station, Texas A&M University System, College Station 77843. K. M. El-Zik, Professor, Department of Soil and Crop Sciences, Texas Agricultural Experiment Station, Texas A&M University System, College Station 77843. Plant Dis. 75:56-58. Accepted for publication 24 June 1990. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/PD-75-0056.

Field plot studies were conducted in 1987 and 1988 to evaluate 12 upland cotton (Gossypium hirsutum) genotypes for relative susceptibility and lint yield production in the presence of Phymatotrichum omnivorum. Susceptibility differed among genotypes; MLB2BENH-1-85 generally had a low disease incidence, while C4HUGBEH-1-2-86 had the highest incidence. Differences also occurred among genotypes for lint yield, with CABUCD3H-1-86, BLLCABS-1-86, and C4HUGBEH-1-2-86 producing significantly more lint than Lankart LX571. Genotypes with less disease incidence and high lint yield production, combined with cultural practices for reducing the survival of P. omnivorum, should provide a beneficial approach for disease control.