分蘖期低温胁迫对东北水稻主栽品种产量及光合特性的影响

Effects of Low Temperature Stress during Booting Stage on Yield and Photosynthetic Characteristics of Cultivated Rice in Northeast of China

以24个东北水稻主栽品种为供试材料,通过人工气候室模拟水稻分蘖期低温胁迫条件,研究低温胁迫对东北水稻主栽品种产量及光合特性的影响。结果表明,在水稻光合特性方面,低温胁迫下不同耐冷性水稻品种叶片净光合速率(Pn)、气孔导度(Tr)、蒸腾速率(Gs)均明显下降,且下降幅度表现为低抗品种>中抗品种>高抗品种,而胞间CO2浓度(Ci)则有所上升;在水稻产量及构成因素方面,低温胁迫下不同耐冷性水稻品种每公顷穗数、每穗实粒数、结实率和千粒重均有所下降,其对产量构成因素影响大小表现为每公顷穗数>每穗实粒数>千粒重,尤对低抗品种影响明显。

Using 24 northeast rice cultivars as teat materials and imitating low temperature stress treatment inthe rice tillering stage in the artificial climate chamber, effects of low temperature stress on yield and photosyntheticcharacteristics of northeast rice cultivars were studied. The results showed leaf net photosynthetic rate（Pn）, stomatalconductance（Tr）, transpiration rate（Gs） of different cold tolerance rice cultivars were declined under low tempera-ture stress, and the extent of decline was low resistance cultivars 〉medium resistance cultivars 〉high resistancecultivars. The intercellular CO2concentration（Ci） increased under low temperature stress. As to the rice yield andcomposition factors, panicle number per hectare, grains per ear, seed rate and 1000-grain weight decreased underlow temperature stress, the order of influence on the yield indicated panicle number per hectare 〉grains per panicle 〉1000-grain weight, which was especially obvious on the weak cold-resistant varieties.