液体硅钾肥对水稻冠层结构、光合特性及产量的影响

Effects of liquid silicon-potash fertilizer on rice canopy layer structure,photosynthetic characteristics and grain yield

为研究液体硅钾肥对水稻冠层结构、光合特性及产量的影响,以Y两优1号为材料,分别在倒3叶、倒4叶期喷施液体硅钾肥(剂量为3 000 ml/hm2),测定水稻冠层的光合特性、产量构成及茎鞘物质转运的变化。结果表明:施用液体硅钾肥后水稻茎蘖成穗率提高,结实期剑叶具有较低的蒸腾速率,较高的叶绿素含量(SPAD值)、光合速率、胞间CO2浓度和气孔导度,能维持较高的植株顶部3张叶的叶面积指数(LAI)及改善冠层结构,提高光能利用效率,并提高物质累积与转运。在倒3叶期喷施液体硅钾肥效果最佳,喷施后水稻冠层结构适宜,群体内光分布合理,其结实率、每穗实粒数、千粒重存在优势,有效穗数、理论产量、实际产量显著高于对照。因此,在倒3叶期喷施液体硅钾肥可提高水稻产量。

Hybrid rice Y Liangyou 1 was used to investigate the photosynthetic characteristics of canopy, yield com-ponents and translocation characters of reserves in stem and leaf sheath by spraying liquid silicon-potash fertilizer equally（3 000 ml/ hm2 ） at growth stages of 3rd and 4th leaves from the top, respectively. The results showed that spraying liquidsilicon-potash fertilizer could increase the stem tillers earing rate, chlorophyll content in flag leaves during grain fillingstage, photosynthetic rate, intercellular CO2 concentration and stomatal conductance of rice, while reduce the transpirationrate of flag leaf at filling period. In addition, spraying liquid silicon-potash fertilizer could maintain the high-performanceleaf area index （LAI） in top three leaves, improve the canopy architecture, and increase the light utilization efficiency anddry matter accumulation and allocation of rice. Among the three treatments, spraying fertilizer at stage of 3rd leaves fromthe top was more favorable for canopy architecture and sunlight distribution in plant colonies, and as a result the seed set-ting rate, filled grain number per panicle and 1 000-grainweight, panicle number, and actual output were muchhigher.