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INFLUENCE OF BIOTYPE E GREENBUGS ON BIOCHEMICAL PROPERTIES OF SORGHUM
Abstract
Studies were conducted at the University of Nebraska Field Laboratory at Mead, Nebraska, to describe changes that occur in glucose, fructose and sucrose composition of seven sorghum (Sorghum bicolor (L.) Moench) cultivars as the result of greenbug (Schizaphis graminum (Rondani)) infestation. Four cultivars were classified as resistant and three as susceptible to greenbug damage. An additional susceptible cultivar, 'Combine Kafir-60' (CK-60), was included which was sampled on a weekly basis. The plants were sampled at preboot, anthesis, grainfill and physiological maturity. The stalks of these cultivars were analyzed for glucose, fructose and sucrose composition at each growth stage. Other parameters that were examined were plant height, greenbug counts, number of dead leaves, insect damage ratings, and the incidence of stalk and peduncle rots. Analysis of the data indicated that there were significant cultivar by year by infestation interactions for the three sugars measured. Sucrose was noted to be more abundant than the two monosaccharides. Significant differences were found at the different growth stages. The non-infested cultivars had more sugar accumulations than the infested cultivars. During the physiological maturity stage, declines in sugar level were observed for all cultivars. The resistant cultivars had higher sugar accumulations than the susceptible cultivars. Cultivar 803512 was observed to have a relatively high sugar level at all sampling dates. When CK-60 was sampled on a weekly basis, the results indicated weekly fluctuations in glucose, fructose and sucrose levels. The greenbug densities varied from one growth stage to another with the susceptible cultivars having higher densities than the resistant cultivars. Analysis of plant height data showed no significant differences between infested and non-infested cultivars. Damaged ratings indicated significant differences between infested and non-infested cultivars. No significant differences were observed between infested and non-infested cultivars for stalk rot damage. Significant differences were obtained between infested and non-infested cultivars for 1982, but not for 1983 for peduncle rot damage.
Subject Area
Entomology
Recommended Citation
OGBONNAYA, CHUKWUEMEKA ALFRED, "INFLUENCE OF BIOTYPE E GREENBUGS ON BIOCHEMICAL PROPERTIES OF SORGHUM" (1985). ETD collection for University of Nebraska-Lincoln. AAI8516878.
https://digitalcommons.unl.edu/dissertations/AAI8516878