冬小麦节水高产栽培群体光合特征

 研究了不同灌水条件下小麦群体光合的变化,并突出考察了非叶器官光合性能特征及其对籽粒产量的贡献。结果表明,小麦开花后群体非叶器官面积与产量呈显著正相关,随着灌水量增加,群体绿色面积中非叶器官面积比例减小;与旗叶相比,非叶器官叶绿素相对含量(SPAD值)。F_v/F_m值、净光合速率均较低,但光合功能期较长,在灌浆后期能保持较高的光合活性;在旗叶节以上器官光合物质对穗粒重的总贡献率中,非叶器官光合贡献的比例占70％～80％,且随灌水量减少而增大。节水高产群体开花后总绿色面积大,其中非叶绿色面积比例高,而单茎叶面积较小,叶层透光好,群体光合速率和WUE均较高。

Canopy Photosynthetic Characteristics of Population of Winter Wheat in Water-saving and High-yielding Cultivation

Canopy photosynthetic rate (CPR), especially non-leaf organs photosynthetic characteristics of winter wheat were studied under different irrigation conditions, and the contribution proportion of different organ photosynthates to grain yield were measured. Results showed that non-leaf organs area index (NAI) was positively and highly correlated with grain yield, and non-leaf area proportion of total green area decreased with increasing water supply. Compared with flag leaf blade, non-leaf organs were lower in SPAD value, Fv/Fm and photosynthetic rate, but lasted longer photosynthetic function, and could keep higher photosynthetic activity in the later period of grain-filling. Photosynthate contribution of non-leaf organs above flag leaf node to grain yield increased with decreasing water supply, and was significantly higher than that of flag leaf blade. The water-saving and high-yielding canopy of winter wheat had high green area index, great proportion of non-leaf area and small top leaf blades, which led to higher CPR and WUE after anthesis.