| The hybrid combination of Indica japonica subspecies showed stronger heterosis than the hybrid combination of varieties, but from the heading to maturity, lots of issues such as ultra-slow growth, high plant lodging, lower panicle setting rate,grain plumpness lag relief often appear,thus affecting the grain yield,being the obstacle problems in the utilization of subspecies heterosis.The research on83S/R197,83S/R292, Y58S/R197, Y58S/R292, Peiai64S/R292five subspecies combinations, and5varieties of hybrid combinations Y58S/68-117,promotion of Peiai64S/68-117,83S/68-117, Y58S/88-116,83S/88-116andthe production of hybrid combination Yueyou9113as control material, fromheading to maturity were measured periodically dry matter accumulation, bendingforce, being the mature check panicle traits. The following is the main results and conclusions.1,In various parts of plant’s dry matter accumulation and allocation:all the tested combinations, from heading to maturity;the stem’s and the leaf’s dry matter content was significant or very significant difference between the tested combination.The Indica-japonica subspecies crosses Pei ai64S/R292stem, leaf dry matter accumulation strong performance advantage of the heading stage, stem dry matter of36.36g/plant, leaves dry matter of14.81g/plant.The Indica-japonica subspecies crosses Pei ai64S/R292stem dry matter (28.40g/plant) compared to the combination of Indica varieties significant advantage,and the other combinations between subspecies indica varieties than the combination of dry plant stems no significant material advantage.The Indica-japonica subspecies crosses83S/R197and Pei ai64S/R292of spike dry matter per plant was62.21g/plant,59.24g/plant, was significantly associated with significantly higher than the other combinations.2, Output rate of dry matter in the stem and stem dry matter conversion rate:five Indica-japonica subspecies crosses of the stem dry matter output rate than indica varieties no advantage, and in the stem dry matter conversion the ratio between indica and japonica hybrid rice combinations Y58S/R292conversion rate of culm material has obvious advantages, indicating that maternal Y58S group and R292with its stem dry matter can be more effectively transported to spike. 3, In terms of plant stem bending force:all the tested combinations maturity of less than full heading plant flexural strength and flexural strength, mainly due to increasing maturity spike dry matter; among five subspecies crosses at heading stage, lodging capability maturity between six varieties of Indica hybrids.4,In agronomic traits:the Indica-japonica subspecies crosses’s height than the combination of indica varieties high21.1-23.2cm, average fertility long3.Id; plant average effective panicles (13.6spike) than among indica varieties combination (15.22spike); average spikelets per panicle number representing varieties combine multiple49per unit area spikelets significantly or very significantly higher than among indica varieties crosses, indicating between subspecies combination of storage capacity greater than indica varieties combinations. Combination between subspecies setting rate (76.33%) than among indica varieties combination (86.66%), while high yield per plant4.97g.5,According to the above results, the five inter subspecific hybrid combinationbending stress at heading stage, maturity stage was strong in indica hybrid combination; in heading to maturity stage of stem, leaf dry matter conversion rate, dry matter output rate than indica hybrid combination of unit area there is no advantage; spikelets than indica hybrid combination; seed setting rate lower than six Indica Hybrid combination. Therefore, this experiment tested five intersubspecific combinations to solve the full heading stage, maturity stagelodging problem; the subspecies hybrid "capacity unit area" big, strong is still lower than that of Indica Hybrid combination. From the test results that theintersubspecific combinations, should be through selection and cultivation measures parent, in keeping with its lodging resistance ability, promote the stalk,leaf dry matter translocation to panicles, resulting in better solution. |
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