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The southern green stink bug, Nezara viridula (L.), occurs worldwide and can transmit disease-causing organisms in cotton, Gossypium hirsutum L., and other high-value commodities. Variable coloration in adults has long been known, with the common “entirely green” color morph occurring throughout its known range, including Central Texas in the United States. A female adult N. viridula with dorsal yellow coloration along the anterior margins of the lobes, anterior margin of pronotum, and connexivum was collected in Central Texas. This color pattern aligns with a different color morph - N. viridula type F – and this report constitutes the first record of this color morph in the United States. To date, adults of the species have been detected in 16 different forms/coloration. Also, this report reconciles some inconsistencies in earlier reports to clarify distribution of N. viridula type F. This information should prove useful to growers who might encounter this color morph and to researchers and taxonomists specializing in the biology and ecology of N. viridula. [ABSTRACT FROM AUTHOR]

Using imbalanced historical yield data to predict performance and select new lines is an arduous breeding task. Genome-wide association studies (GWAS) and high throughput genotyping based on sequencing techniques can increase prediction accuracy. An association mapping panel of 227 Texas elite (TXE) wheat breeding lines was used for GWAS and a training population to develop prediction models for grain yield selection. An imbalanced set of yield data collected from 102 environments (year-by-location) over 10 years, through testing yield in 40–66 lines each year at 6–14 locations with 38–41 lines repeated in the test in any two consecutive years, was used. Based on correlations among data from different environments within two adjacent years and heritability estimated in each environment, yield data from 87 environments were selected and assigned to two correlation-based groups. The yield best linear unbiased estimation (BLUE) from each group, along with reaction to greenbug and Hessian fly in each line, was used for GWAS to reveal genomic regions associated with yield and insect resistance. A total of 74 genomic regions were associated with grain yield and two of them were commonly detected in both correlation-based groups. Greenbug resistance in TXE lines was mainly controlled by Gb3 on chromosome 7DL in addition to two novel regions on 3DL and 6DS, and Hessian fly resistance was conferred by the region on 1AS. Genomic prediction models developed in two correlation-based groups were validated using a set of 105 new advanced breeding lines and the model from correlation-based group G2 was more reliable for prediction. This research not only identified genomic regions associated with yield and insect resistance but also established the method of using historical imbalanced breeding data to develop a genomic prediction model for crop improvement. [ABSTRACT FROM AUTHOR]

Leaffooted bug, Leptoglossus phyllopus (L.) (Hemiptera: Coreidae), has been observed on late-season cotton in south Texas and elsewhere in USA. Field-collected leaffooted bugs were caged on cotton in 2013 and 2014 to characterize symptoms and distribution of boll injury within the cotton plant and within the context of the insect's late-season occurrence (about 5 nodes above white flower). Boll injury and symptoms of cotton boll rot on cotton plants infested with leaffooted bug were similar to those caused by stink bugs and plant bugs. In 2013, there was more boll injury to younger bolls (on average) in reproductive middle branches 6 to 10 (1.28 ± 0.25 boll injury, based on a 0 to 4 scale) than on the relatively older bolls in lower branches 1 to 5 (0.50 ± 0.13), when infesting cotton with one leaffooted bug per plant. Cotton boll rot generally followed the same pattern: higher frequency of boll rot symptoms on bolls in the middle branches (29.4% ± 8.0) than in lower branches (9.2% ± 2.1). In 2014 under severe water-stress conditions, the amount of boll injury and cotton boll rot was marginally lower, and significant differences were not detected between middle and lower branches. When yield was measured in 2013, there were no differences detected between infested and uninfested plants despite substantial boll injury and cotton boll rot. Overall, boll injury and cotton boll rot data supported leaffooted bug as a damaging cotton insect, although yield loss was not detected experimentally late-season which coincided when leaffooted bug has been observed in production fields. We propose that risk to yield is low when leaffooted bug movement to cotton is detected late-season, while risk to yield may increase if leaffooted bugs move to cotton earlier when bolls are younger. Further study is warranted to evaluate degree of risk across cotton boll age, development, and water stress. Leaffooted bug feeding on a green cotton boll (A) causing external (B) and internal (C) carpel wall injury, and leading to lint injury with no (D, left) and positive (D, right; E: cross-section) symptoms of cotton boll rot. Image 1 • Cotton boll injury and rot caused by leaffooted bug were similar to those caused by stink bugs. • Boll injury and rot was greater on younger bolls of middle branches than bolls on lower branches. • Yield loss was not detected experimentally late-season but risk likely increases earlier in season. • Further study is warranted to evaluate degree of risk across cotton boll age and development. [ABSTRACT FROM AUTHOR]

Biotypic diversity of the greenbug, Schizaphis graminum (Rondani) (Hemiptera: Aphididae), was assessed among populations collected from cultivated wheat, Triticum aestivum L., and sorghum, Sorghum bicolor (L.) Moench, and their associated noncultivated grass hosts. Greenbugs were collected during May through August 2002 from 30 counties of Kansas, Nebraska, Oklahoma, and Texas. Discounting the presumptive biotype A, five of the remaining nine letter-designated greenbug biotypes were collected; however, biotypes C, F, J, and K were not detected. Biotypes E and I exhibited the greatest host range and were the only biotypes collected in all four states. Sixteen greenbug clones, collected from eight plant species, exhibited unique biotype profiles. Eleven were collected from noncultivated grasses, three from wheat, and two from sorghum. The most virulent biotypes were collected from noncultivated hosts. The great degree of biotypic diversity among noncultivated grasses supports the contention that the greenbug species complex is composed of host-adapted races that diverged on grass species independently of, and well before, the advent of modern agriculture. [ABSTRACT FROM AUTHOR]

The article offers information on the registration of sorghum germplasm lines Tx2962 through Tx2978, which was developed and released by the Texas Agricultural Experiment Station and the Texas A&M University System in 2006. These contain a moderate to high level of resistance to greenbug biotype E, Rondani, and a moderate level of resistance to greenbug biotype I in seedling stage greenhouse tests. The selections were made to improve the yield potential, adaptation, disease resistance, and grain weathering resistance. Registration number and scientific name of the rice were also provided.

Polyacrylamide gel electrophoresis was used to resolve esterase isozymes that were related to insecticide resistance in greenbug, Schizaphisgraminum (Rondani). This report documents the occurrence of esterase polymorphisms in the Midwest and assesses differences in regional occurrences. In total, 13,863 individual greenbugs from Kansas, Texas, Oklahoma, and Colorado were tested between 1991 and 1995. The occurrence of resistant greenbugs appeared to be greatest in the southwestcrop reporting district of Kansas and the north plains crop reporting district of Texas. The overall incidence of pattern 1 resistant greenbugs declined from 7.1% in 1991 to <1% in 1994 and 1995. Pattern 2 resistant greenbug occurrence varied from year to year (5.7-29.8%). Several explanations for the spatial occurrence of resistant greenbugsand several techniques for managing resistant greenbug populations are offered. [ABSTRACT FROM AUTHOR]