Recipient Organization
TENNESSEE TECHNOLOGICAL UNIVERSITY
BOX 5033
COOKEVILLE,TN 38505
Performing Department
(N/A)
Non Technical Summary
Cotton is the world's leading fiber crop, and cottonseed also produces 14-19% of farm-gate value. Elevating cotton to a more important food crop through improving seed oil content (SOC) and quality can significantly increase the net income for cotton producers and cottonseed processers. The SOC and its genetic variation within Upland cultivars are both low. Through introgression genetics and breeding between Upland (G. hirsutum) and Pima cotton (G. barbadense), cotton SOC and oil quality can be greatly improved by utilizing desirable interspecific transgressive segregation. The long-term objective is to develop high SOC Upland cotton with improved oil quality, high-yield and desirable fiber quality for the U.S. Cotton Belt. After a field test of 2,900 introgression lines (ILs) followed by multi-location field tests of selected ILs, we will release a cultivar and many elite ILs with high SOC and improved oil quality that is beyond the current boundary in Upland cotton, facilitating a breakthrough in elevating cotton to a more important oilseed crop for the first time. Through a genome-wide association study (GWAS) of 500 selected ILs based on genome re-sequencing, GWAS of 100 selected ILs based on RNA-seq, and QTL-seq, we will identify quantitative trait loci (QTL) and underlying candidate genes for enhancing SOC and fatty acids for further molecular genomic studies and for portable marker development to be used in molecular breeding. The results will provide the most comprehensive genetic and genomic insight into the molecular basis of transgressive segregation for SOC and fatty acids in cotton.
Animal Health Component
100%
Research Effort Categories
Basic
0%
Applied
100%
Developmental
0%
Goals / Objectives
The long-term goal of this project is to develop new Upland cotton cultivars with high seed oil content and improved oil quality, while maintaining high-yielding and high fiber quality in the conventional glandless or glanded background for cotton production in the U.S. Cotton Belt. The specific objectives are:a. To identify cotton germplasm and introgression lines with high cottonseed oil content and improved oil quality (lower saturated fatty acids and higher polyunsaturated acids) and increased dihydrosterculic acid (DHSA, cpa 19:0) content.b. To identify genes or candidate genes underlying quantitative trait loci (QTLs) that enhance superior oil content and fatty acid quality and are linked to portable markers that are useful for molecular breeding.c. To release 3 to 5 improved advanced breeding lines and possibly one commercial Upland cultivar with high cottonseed oil content and improved oil quality.
Project Methods
In 2025,30 advanced intorgression lines will be selectedwill be selected from the 2023-2024 field tests for further testing in four locations (SC, MS, TX and NM)representing different cotton production regions. The tests including the selected ILs and 3commercial checks will be arranged using a randomized complete block design (RCBD) with 3-4 replications. The plot size will be 2- rows × 10-15 m with a row-spacing of 0.92 m. Seed planting and crop managements will be the same as subscribed for the local cotton management in each location. At maturity, 25 open bolls from the middle of plants will be hand harvested for ginning using a 10 or 20-saw lab gin. Seed oil content, fatty acids, fiber quality, yield and other agronomic traits will be determined. Analysis of variance (ANOVA) will be performed to separate variations due to genotype (G), location (L), G x L and error. In 2026, results from 2023-2025 will be jointly analyzed to choose top one introgression line for release as a commercial culttivar and 2-3 lines to be released as germplasm lines. Release notices will be drafted to be approved by NMSU and TTU and published in Journal of Plant Registrations. Seeds will be deposited in the National Plant Germplasm System (USDA-ARS).