Location: Crop Genetics ResearchTitle: Selection of Gossypium hirsutum genotypes for interspecific introgression from G. arboreum using ovule culture
Submitted to: African Journal of Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/8/2015
Publication Date: 4/22/2015
Citation: Erpelding, J.E. 2015. Selection of Gossypium hirsutum genotypes for interspecific introgression from G. arboreum using ovule culture. African Journal of Biotechnology. 14:1373-1378.
Interpretive Summary: Four species of cotton are cultivated worldwide, but upland cotton comprises approximately 95% of all cotton production. One cotton species, Gossypium arboreum that is typically grown on marginal lands in India, Pakistan, and China using few inputs, is a potential source of insect, disease, and nematode resistance, and drought tolerance. Gossypium arboreum has half the number of chromosomes as upland cotton. Although this species can be crossed with upland cotton, the developing seeds will abort within five days after cross-pollination. One method to recover plants from these crosses is to remove the developing seeds prior to abortion and grow them in tissue culture in the laboratory. The success rate of the tissue culture procedure can vary due to many factors. The upland cotton variety used as a parent in the crosses could influence the success rate, but no data is available to determine the best parent to use in the crosses to achieve a higher recovery rate of plants from tissue culture. To evaluate this factor, 26 upland cotton varieties were used in crosses with five Gossypium arboreum varieties and the developing seeds were removed from the plants and grown in tissue culture. The immature seeds derived from crosses for 16 upland cotton varieties germinated in tissue culture and plants were obtained for seven of the varieties. Several upland cotton varieties used in the crosses showed a better success rate. However, the Gossypium arboreum variety used in the crosses also influence the success rate. Results of the study would suggest crossing Gossypium arboreum varieties with several different upland cotton varieties would increase the likelihood of recovering plants from tissue culture. Additionally, the plants derived from the crosses in this study will enhance genetic diversity to develop improved upland cotton varieties.
Technical Abstract: Ovule culture is one of the techniques currently used to introgress desirable traits from Gossypium arboreum germplasm into G. hirsutum cultivars. Twenty-six G. hirsutum breeding lines were used as female parents in crosses with five G. arboreum accessions to determine if the G. hirsutum parent influenced the germination and recovery of plants from ovule culture. Variation in boll weight and the number of ovules per boll was observed for crosses with the G. hirsutum lines, but heavier bolls and a greater number of ovules per boll were not associated with a higher germination rate. Ovules derived from crosses with 16 G. hirsutum lines showed germination with plants recovered from seven lines. The breeding line DES 119 showed a better success rate and typically produced smaller bolls with fewer ovules. However, results would suggest the G. arboreum accessions had a greater influence on the success rate compared to the G. hirsutum lines.