敦煌绿洲区覆膜补灌对谷子光合特性农艺性状及产量的影响

在年降雨量不足40 mm的敦煌绿洲灌区,以谷子为材料,采用裂区试验,研究了覆膜栽培条件下拔节、抽穗和灌浆各阶段灌一次水对其光合特性、农艺性状及产量的影响。结果显示:在播前统一灌600 m~3·hm~(-2)底墒水的情况下,抽穗期灌600 m~3·hm~(-2)水处理(A3),谷子的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)及叶绿素含量显著的高于生育期内不灌水(A1)、拔节期灌600 m~3·hm~(-2)水(A2)和灌浆期灌600 m~3·hm~(-2)水(A4)处理,胞间CO_2浓度(Ci)因品种不同各处理间也存在较大差异;抽穗期灌600 m~3·hm~(-2)水(A3)不仅抽穗明显提前,株高、主穗长、单株穗重、单株粒重、单株草重显著高于A1、A2、A4,且产量也极显著高于A1、A2、A4;相关分析表明,不同处理净光合速率、蒸腾速率、气孔导度、叶绿素含量均与产量显著正相关,光合速率、蒸腾速率、气孔导度间彼此极显著相关。

Effect of supplemental irrigation on photosynthetic characteristics, agronomic traits and yield of foxtail millet under condition of film mulching in Dunhuang oasis

In Dunhuang oasis area where annual rainfall is less than 40 mm,a split plot experiment was conducted to explore the effect of irrigation at jointing,heading and filling stages on the photosynthetic characteristics,agronomic traits and yield of foxtail millet (Setaria italica L.) under the condition of film mulching.Results showed that,under the condition of identical irrigation with 600 m3· hm-2 water before planting,the photosythetic rate (Pn),transpiration rate (Tr),stomatal conductance (Gs) and chlorophyll content of foxtail millet in the treatment of heading stage irrigation with 600 m3·hm-2 water (A3) were significantly higher than those in the treatments of no irrigation (A1),jointing stage irrigation with 600 m3·hm-2 water (A2) and filling stage irrigation with 600 m3·hm-2 water (A4).Intercellular CO2 concentration (Ci) was also much different among different treatments,being affected by different cuhivars.Compared with A1,A2 and A4,the treatment of A3 promoted heading time remarkably,increased plant height,main spike length,spike weight per plant,grain weight per plant and straw weight per plant significantly,and raised yield very significantly.Correlation analysis showed that photosynthetic rate transpiration rate,stomatal conductance and chlorophyll content were significantly positively correlated with yield,while photoynthetic rate,transpiration rate and stomatal conductance were very significantly correlated with each other.