| Under aeroponic culture condition, fifteen upland rice varieties and twelve lowland rice varieties were used in this study. Comparing to lowland rice, upland rice has the stronger ability of water control, less root number, thicker basal root thickness, longer root length, thicker root cortex, bigger diameter of roots, more root trachea, and more root biology products. There are significant difference between upland rice and lowland rice at diameter of root central cylinder and root trachea number. And the correlation analysis showed there are significantly positive correlation between root trachea and stem dry weight of upland rice, the dry weight and fresh weight was correlated significantly with root 0-20cm fresh weight of lowland rice, while the dry weight and fresh weight were correlated significantly with root 20-40cm dry weight and fresh weight in upland rice. Root cortex was correlated significantly with root water content in upland rice, while no significant correlation was observed in lowland rice.A Recombinant Inbred Line (RIL) population including 120 plants, derived from the cross between Japonica upland rice IRAT109 and paddy rice Yuefu, were used in this study. Phenotypic values of root traits, index of drought resistance, stoma density, stoma length, midrib thickness, basal thickness of ear, PEG treatment and comeum wax content of RIL population and the parents were obtained under upland, lowland, sheded cultivation and water planting conditions. Using index of drought resistance (IDR), the ratio of yield under upland condition to yield under lowland condition, as the criteria of drought resistance, correlation analysis and heritability analysis. QTLs associated with these traits were located on the molecular linkage map.Midrib Thickness is thicker at upland than lowland (18.6% ) , by analysis the broad sense of heritability, we found Midrib Thickness was easily effected at lowland than upland. Basal thickness of ear is thicker at lowland than upland; by analysis of broad sense of heritability, we found Basal Thickness of Ear would be effected easily at lowland than upland. The result showed that Midrib Thickness and Basal thickness of ear has no significantly correlation with IDR, but correlated with yield of per plant.We detected 22 QTL of diameter of root central cylinder in upland and lowland, 8 of them had a general contribution over 10%,such as RM218-RM517 in chr3 and RM1124-RM552 in chr11. contribution was 11.17%, 11.21% respectively; as to basal thickness of ear, we detected 23 QTL, 6 of them had a general contribution over 10%,such as RM259-RM490 in chr1 and RM1124-RM552 in chr11, contribution was 16.93%,11.31% respectively,Correlation analysis indicated that stoma density significantly correlated with IDR; stoma length correlated with stoma density negatively, but had no correlations with IDR.9 QTL were found of Stoma density and most of them were additive effect QTLs, and 4 had a general contribution over 10%,such as RM1183-RM1152, RM1244-RM1297 in chr1. contribution was 10.95%,13.17% respectively.Wax content correlated significantly with IDR. 3 had a general contribution over 10%, such as RM110-RM423, RM1092-RM530 in chr2; PEG stress at shoot stage strongly effected by environment. 10 QTL were detected and 2 had a general contribution over 15%, after rewatering 1 day and 10 day, 19 and 17 QTL were detected respectively, and each had a 4 QTL had a general contribution over 10%.Among the QTLs with high general contribution, two of them was pleitropic QTLs, RM110-RM423 in chr2 was found had a high general contribution to wax content We can use these QTLs with high general contribution in fine mapping and marker-assistant breeding.In all of these QTLs, QTL between RM110-RM4223 in chr2 control wax content of corneum and PEG stress treatment, QTL between RM1124-RM552 in chr11 control diameter of root central cylinder and basal thickness of ear.
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