Browsing by Subject "Cotton -- Diseases and pests"
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Item Item Growth interaction between cotton and pigweed(Texas Tech University, 1970-05) Tseng, Hui-YingNot availableItem Impact of insect predators and a pyrethroid insecticide on field populations of the cotton aphid, aphia gossypii glover, in Texas High Plains cotton(Texas Tech University, 1995-08) Kidd, Phillip WNot availableItem Inheritance of resistance to the cotton aphid in Gossypium herbaceum(Texas Tech University, 2001-05) Alexander, Justin DeanNot availableItem Numbers of bacteria and their distribution on cotton plants during development(Texas Tech University, 1987-08) Cartagenova, Maria IsabelNot availableItem Population dynamics of 'Aphis gossypii' in cotton: laboratory studies and field validation(Texas Tech University, 2004-12) Sapkota, Anand PNot availableItem Screening for resistance to Aphis gossypii Glover, the cotton aphid, in cotton genotypes(Texas Tech University, 2000-05) Reed, BlayneThe cotton aphid. Aphis gossypii Glover (Homoptera: Aphididae), has been a serious pest throughout the Cotton Belt and around the world. This pest not only takes vital sugars and amino acids from the growing cotton plant, but also deposits excretions known as "honeydew" onto cotton fibers. This results in "sticky cotton" which causes major problems in textile mills, and subsequently a lower price to producers.Item Screening for tolerance to verticillium wilt in cotton(Texas Tech University, 1996-08) Adair, Allen ScottNot availableItem Selected effects of diapause boll weevil control programs on two non-target insects(Texas Tech University, 1968-06) Hills, Thomas MNot availableItem Survey and assessment of cotton insects associated with weeping lovegrass, Eragrostis curvula (Schrad.) nees, in wind-strip cropping systems(Texas Tech University, 1987-12) Brown, Charles MarkWind erosion of topsoil is a severe problem in the Texas High Plains, an area of intensive cotton production. In this investigation, a survey and assessment of insects associated with weeping lovegrass, Eragrostis curvula (Schrad.) Nees, was conducted to determine the entomological problems and benefits of a cotton/weeping lovegrass wind-strip cropping system on the High Plains. The western flower thrips, Frankliniella occidentalis Pergande, was the most economically important cotton pest found in association with weeping lovegrass. Although some cotton pests were associated with weeping lovegrass, no indication of increased pest problems was detected in cotton grown between terraces sown to weeping lovegrass. Key beneficial arthropods of High Plains cotton pests were found also in association with weeping lovegrass. Therefore, weeping lovegrass wind-strips may serve as an early source of beneficial arthropod population buildup. An overwintering investigation of the boll weevil, Anthonomus grandis Boheman, conducted in the Texas Rolling Plains area indicated that caged boll weevils could successfully overwinter in the crowns of weeping lovegrass.Item The use of protein gel electrophoresis for the detection of host plant resistance in cotton to the root-knot nematode(Texas Tech University, 1986-08) Smith, Roger GaryThirty-two germplasm sources of Gossypi um hi rsutum L. were inoculated with 1,000 larvae of Meloidogyne incognita (Chitwood) for six days. Root segments were excised and electrophoretically separated for protein content. Results show that resistant cotton plants respond to infection by root-knot nematodes quicker and more intensely than susceptible cotton plants. The most common type of protein band variation observed was in the darkness and thickness of various bands, and individual bands did not change uniformly among germplasms. These results indicate that polyacrylamide gel electrophoresis can be used to eliminate cotton plants which are susceptible to the root-knot nematode and can become a practical means to enhance the development of nematode resistant cultivars on the Texas High Plains.Item Transformation of cotton plants through an alternate DNA delivery approach(Texas Tech University, 2003-12) Xiang, ZhixinThe objective of this research was to introduce chitinase and â-l,3-glucanase genes into cotton to improve resistance to fungal pathogens through the pollen tube pathway-mediated transformation (PTP). To confirm the success of this method, DNA of a plasmid pRTL2-GUS containing uidA (coding sequence for â-glucuronidase) was introduced into cotton (Gossypium hirsutum L.) 'Paymaster HS26', 'Stovepipe', and 'CA3048'. Seeds formed from treated flowers were allowed to mature on the plants. Seedlings grown from seeds harvested from treated flowers were screened for the presence of uidA by PCR and GUS (â-glucuronidase) expression by histochemical assay. The overall transformation frequency was 11.7 %. Southem hybridizations of T1 progeny confirmed that the uidA transgene was integrated into the cotton genome. GUS expressions were detected in the plants of two generations. In T2 progeny, GUS segregation of uidA followed the expected 3:lMendelian genetic ratio. Our results confirmed transformation of uidA via PTP. Chitinases and â-1,3-glucanases have been used in transgenic plants to improve resistance to pathogens. In this study, fertile, transgenic cotton (Gossypium hirsutum L.) plants expressing a bean chitinase and an Arabidopsis â-l,3-glucanase were generated using pollen tube pathway-mediated transformation system. Ch5b from Phaseolus vulgaris L. and bg2 from Arabidopsis thaliana L. were cloned into plasmid pRTL2 driven by the CaMV 35S promoter. The transgenes ch5b and bg2 were successfully delivered into two breeding lines of cotton. Southern blot and slab blot analyses of DNA isolated from T2 progeny demonstrated that the transgenes were stably integrated into the genome of transgenic cotton plants and inherited by the offspring. Expression of the chitinase and â-1,3-glucanase gene was detected in transgenic T2 cotton plants. Transgenic T2 and T3 plants examined for resistance to the fiingal pathogen Rhizoctonia solani Kuhn in a growth chamber exhibited less root rot and fewer hypocotyl lesions than non-transgenic control plants. Greenhouse screening tests indicated that the ability to resist the fungal pathogen R. solani increased in these plants. Our results suggest that the chitinase and â-l,3-glucanase genes functioned in cotton and were expressed in fertile plants. The pollen tube pathway transformation strategy may be useful for the control of other fungal diseases of plants.