Cotton yield losses in areas of south Texas have been associated with various bolls rots affecting reduction in yield, lint quality, and causing deteriorated seed. This study (2011 and 2012) was initiated in two south Texas regions (Coastal Bend and Rio Grande Valley) to determine the incidence and prevalence of cotton boll rots as well as putatively identifying the bacterial microorganisms associated with boll rot in south Texas and determine their pathogenicity. The first portion of this study was conducted to evaluate specific cotton varieties which included; FiberMax (FM) 1740B2F, FM 840B2F, DeltaPine (DP) 1044B2RF, DP 1048B2RF, and Phytogen (PHY) 375WRF in a variety trial located at the Texas A&M University-Kingsville Research Farm. The second portion of the study involved a field survey that was conducted in the Coastal Bend and Rio Grande Valley regions in commercial fields. Cotton bolls exhibiting external damage were collected, dissected, ground, and plated for microorganism quantification and identification. Purified colonies were identified using Gas Chromatographic Fatty Acid Methyl Esters. Data from the studies in both the variety trial and the field surveys showed less than 1% of cotton bolls were infected with boll rots during the 2 yr study. Data demonstrated when comparing the three locations in the south Texas study, boll rot incidence varied between the Coastal Bend and the Rio Grande Valley. Data indicates that Arthobacter, Bacillus, Enterobacter, Flavimonas, Pantoea, and Pseudomonas spp. were the most prevalent microorganisms throughout the observed regions over the 2 yr studies. Pantoea spp. is one of the more predominately-isolated microorganisms from previous research conducted.
January 21, 2016
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