开放式空气CO2浓度增高对水稻颖花分化和退化的影响

在大田栽培条件下 ,研究开放式空气CO2 浓度增加 (FACE) 2 0 0 μmol·mol-1的处理对水稻每穗 1、2次枝梗及其颖花的分化数、退化数、现存数及退化率的影响 .结果表明 ,FACE处理对每穗 1、2次枝梗的分化数及 1次枝梗的退化数、退化率均无显著影响 ,但使 2次枝梗的退化数、退化率显著提高 ,使 2次枝梗现存数明显减少 ;FACE处理对每穗 1、2次颖花的分化数和 1次颖花的退化数、现存数、退化率均无显著影响 ,但使每穗 2次颖花的退化数和退化率显著提高 ;FACE处理使每穗颖花现存数显著减少主要是因为FACE处理使现存 1次枝梗上 2次枝梗大量退化引起 2次颖花退化所致 ;FACE处理使 1次颖花现存数占全穗的比率显著增加 ,使 2次颖花现存数占全穗的比率显著降低 .

Effect of free-air CO2 enrichment(FACE) on spikelets differentiation and retrogression in rice (Oryza sativa)

Effect of Free-Air CO2 Enrichment (FACE), 200 mumol.mol-1CO2 elevation under field condition, on the number of differentiated, retrograded, and survived primary and secondary branches and their spikelets in rice was investigated, and the percentage of retrograded branches and spikelets under FACE treatment were also calculated. Results showed that the number of differentiated primary and secondary branches, the number and percentage of retrograded primary branches per panicle were not significantly affected by FACE, but the number and percentage of retrograded secondary branches per panicle significantly increased under FACE treatment, which resulted in the significant decrease of survived secondary banches. FACE had no significant effect on the number of differentiated, retrograded and survived spikelets on the primary branches per panicle. The number of differentiated spikelets on secondary branches per panicle was not significantly affected by FACE, but FACE treatment significantly increased the number and percentage of retrograded spikelets on the secondary branches per panicle. Significant decrease of survived spikelets per panicle under FACE treatment was chiefly caused by marked increase of retrograded spikelets on the secondary branches of survived primary branches. FACE treatment significantly increased the surviving percentage of spikelets on the primary branches per panicle, while that on the secondary branches significantly decreased under FACE treatment.