title: Molecular dissection of seedling-vigor and associated physiological traits in rice.
abstract: seedling-vigor is important for crop establishment. There have been reported quantitative trait locus (QTL) analyses on seedling-vigor related morphological traits. However, physiological understanding of these detected QTLs is rather limited. In this study, we employed a recombinant inbred population to detect QTLs for seedling-vigor traits and physiological traits related to seedling-vigor. Germination rate and seedling growth were measured to quantify seedling-vigor. Total amylase activity, alpha-amylase activity, reducing sugar content, root activity and seed weight were determined. Correlations were observed between the seedling-vigor and physiological traits. QTL analysis reveals that the intervals of RG393-C1087-RZ403 on chromosome 3, C246-RM26-C1447 and R830-R3166-RG360-C734b on chromosome 5, and the interval of Waxy on chromosome 6 are the four main chromosomal regions controlling seedling-vigor. Several QTLs for amylase activities, reducing sugar content and root activity were localized in the similar regions as the QTLs for seedling-vigor. The results suggest that these traits were under the control of pleiotropic and/or closely linked QTLs. The implications of the results in the understanding of the physiological basis of seedling-vigor were discussed.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: H.
authors.initials: H
authors.lastname: Cui
authors.forename: B.
authors.initials: B
authors.lastname: Peng
authors.forename: Z.
authors.initials: Z
authors.lastname: Xing
authors.forename: G.
authors.initials: G
authors.lastname: Xu
authors.forename: B.
authors.initials: B
authors.lastname: Yu
authors.forename: Q.
authors.initials: Q
authors.lastname: Zhang