TY - JOUR
T1 - Molecular mapping of genes affecting pubescence of cotton
AU - Wright, R. J.
AU - Thaxton, P. M.
AU - El-Zik, K. M.
AU - Paterson, A. H.
N1 - Funding Information:
From the Multi-Adversity Resistance Cotton Breeding Program (Wright, Thaxton, and El-Zik) and the Plant Genome Mapping Laboratory (Paterson), Department of Soil and Crop Sciences, Texas A&M University, College Station, TX 77843–2474. This work was funded in part by a grant from the Texas Agricultural Experiment Station to K.M.E. and A.H.P., and by grants from the Texas Higher Education Coordinating Board and USDA Plant Genome Program to A.H.P. Address correspondence to A. H. Paterson at the Department of Crop and Soil Science, University of Georgia, Athens, GA 30602.
PY - 1999/1
Y1 - 1999/1
N2 - Upland cotton (Gossypium hirsutum L.) genotypes have varying densities of trichomes on the leaves and stems of mature plants, hence their species name. Most modern cotton cultivars are 'smooth' with few if any trichomes. Absence of trichomes reduces the attractiveness of the cotton plant to some major insect pests, reducing reliance on pesticides. A detailed RFLP map was used to map genes affecting density of leaf and stem trichomes. Based on quantitative measures of young and mature leaves, four QTLs were mapped. A QTL on chromosome 6 that imparts dense leaf pubescence is inferred to be the t1 locus. A second QTL on chromosome 25, which is homoeologous to chromosome 6, fits the description of the t2 locus. Two additional QTLs, QLP1 and QLP2, explained significant phenotypic variation in leaf pubescence - these may represent the t3, t4, or t5 loci. Some QTLs appeared to be specific to particular developmental stages; for example, QLP1 reduced hairiness only in young leaves while QLP2 increased hairiness in mature leaves. A single locus associated with variation in trichome density on the stem did not correspond to the genes/QTLs affecting leaf trichomes, suggesting that these traits may largely be controlled by different genes. A widely used qualitative classification system for scoring trichome density (DTL) detected only the chromosome 6 locus and was apparently not sensitive enough to detect alleles such as t2 that had smaller phenotypic effects.
AB - Upland cotton (Gossypium hirsutum L.) genotypes have varying densities of trichomes on the leaves and stems of mature plants, hence their species name. Most modern cotton cultivars are 'smooth' with few if any trichomes. Absence of trichomes reduces the attractiveness of the cotton plant to some major insect pests, reducing reliance on pesticides. A detailed RFLP map was used to map genes affecting density of leaf and stem trichomes. Based on quantitative measures of young and mature leaves, four QTLs were mapped. A QTL on chromosome 6 that imparts dense leaf pubescence is inferred to be the t1 locus. A second QTL on chromosome 25, which is homoeologous to chromosome 6, fits the description of the t2 locus. Two additional QTLs, QLP1 and QLP2, explained significant phenotypic variation in leaf pubescence - these may represent the t3, t4, or t5 loci. Some QTLs appeared to be specific to particular developmental stages; for example, QLP1 reduced hairiness only in young leaves while QLP2 increased hairiness in mature leaves. A single locus associated with variation in trichome density on the stem did not correspond to the genes/QTLs affecting leaf trichomes, suggesting that these traits may largely be controlled by different genes. A widely used qualitative classification system for scoring trichome density (DTL) detected only the chromosome 6 locus and was apparently not sensitive enough to detect alleles such as t2 that had smaller phenotypic effects.
UR - http://www.scopus.com/inward/record.url?scp=0032904250&partnerID=8YFLogxK
U2 - 10.1093/jhered/90.1.215
DO - 10.1093/jhered/90.1.215
M3 - Article
AN - SCOPUS:0032904250
VL - 90
SP - 215
EP - 219
JO - Journal of Heredity
JF - Journal of Heredity
SN - 0022-1503
IS - 1
ER -