Genetic Analysis And Gene Mapping For Sheathed Panicle In Rice(Oryza Sativa L.)

This study we used a sheathed panicle variety YD998 and F2 population generated by YD998 × Nipponbare as experimental material for constructing whole genome genetic linkage map, and then we mapped the QTLs or gene of the sheathed panicle trait. The results are as follows:1. The main agronomic traits of the YD998 included panicle completely wrapped by the flag leaf sheath, dwarf plants, large tillering angle, no uppermost internode, early heading date, short awn. less panicle grain number, small secondary’ branch, and easy shattering, etc.2. The YD998 was treated by different concentrations of GA3 at the end of the spike development. The results showed that with the increasing of concentration of gibberellin, plant height also increased obviously. When the concentration reached 150-200 mg · L-1. plant height reached the highest,and also the sheathed panicle was lightest. Experimental data showed that the degree of reduction sheathed panicle was due to the greater increasing rate of the panicle length than the flag leaf sheath. Our study indicated that GA3 cannot relieve sheathed panicle.3. F2 population generated by YD998× Nipponbare we used as material for constructing whole genome genetic linkage map. A QTL of UFR was detected, on chromosomes 1, and a QTL of FLL was mapped, on chromosomes 2, moreover two QTLs of UIL were obtained, on chromosomes land 2, respectively.4. Furthermore, we finely mapped the sheathed panicle gene to a region of 9.7 cM that was between SSR markers NRM3811 and NRM4100 on chromosome 1 using 19 polymorphic markers and 504 plants which selected from F2 populations (YD998 × Nipponbare).