双季稻区不同栽培方式对水稻光合生理特性、粒叶比及产量的影响

为探明洞庭湖平原双季稻区不同栽培方式对水稻光合生理特性、粒叶比和产量的影响,以常规稻和杂交稻为材料,对塑料软盘育秧抛栽、手插和机插3种栽培方式水稻的光合生理特性、粒叶比和产量进行系统的比较研究。结果表明:1)抛栽和手插水稻叶片的叶绿素含量(SPAD值)在分蘖期、齐穗期和灌浆期均显著高于机插,但各栽培方式间在成熟期无显著差异。2)叶面积指数(Leaf area index,LAI)在水稻主要生育期表现为:抛栽手插机插。3)手插早稻的颖花数/叶面积、实粒数/叶面积和粒重/叶面积分别比机插平均增加17.7%、20.6%和10.0%,抛栽晚稻分别比机插平均增加29.1%、37.3%和12.1%。4)分蘖期、齐穗期和灌浆期,不同栽培方式水稻叶片光合速率大小顺序为抛栽手插机插。5)分蘖期和齐穗期,水稻叶片气孔导度大小顺序为抛栽手插机插;成熟期,则表现为手插机插抛栽。6)水稻各个生育期,叶片蒸腾速率表现为抛栽手插机插,但各栽培方式间均无显著性差异。7)不同栽培方式间水稻产量差异显著,抛栽最高,机插最低;抛栽和手插早稻分别比机插增产1 203.3~1 346.7和776.7~1 045.4kg/hm2,晚稻分别比机插增产2 128.7~2 212.2和1 574.2~1 603.9kg/hm2。说明不同栽培方式水稻光合生理特性和产量有各自特征,与机插相比,抛栽和手插处理提高水稻粒叶比,改善源库关系,有利于改善水稻群体质量和产量构成因素,增加水稻产量。

Effects of different cultivation methods on rice photosynthetic characteristics, grain leaf area ratio and yield in double rice cropping system

To explore the photosynthetic characteristics, grain leaf area ratio and grain yield of early and late rice with different cultivation methods in the double cropping rice system in the Dongting Lake plain, we analyzed the photosynthetic characteristics and grain yield of first and second rice with conventional and hybrid rice varieties by using three different seedling transplanting approaches: seedling parachuting (ST), hand transplanting (HT) and machine transplanting (MT).The results showed: 1) The leaf chlorophyll content (SPAD) of rice plant with ST and HT was significantly higher than that with MT at tillering, heading and grain filling stages.But there was no significant difference among ST, HT and MT at mature stage.2) Meanwhile, the leaf area index (LAI) for different cultivation methods was ST > HT > MT at the main growth stages for both early and late rice.3) Number of spikelets/leaf area, number of filled grains/leaf area, grain mass/leaf area of early rice with HT were 17.7%, 20.6% and 10.0%, which werehigher than that of MT, respectively.Meanwhile, for the late rice with ST was 29.1%, 37.3% and 12.1% which were also higher than that of MT, respectively.4) The net photosynthetic rate of rice leaf was ST > HT > MT at tillering, heading and grain filling stages, respectively.5) And the stomatal conductance was ST > HT > MT at tillering and heading stages, and HT > MT > ST at mature stage, respectively.6) For transpiration rate of rice leaf, there was not significant difference among the three cultivation methods at the main growth stages of early and late rice.7) Yield of early and late rice with different cultivation methods was significantly different, with ST the highest, while that of MT was the lowest.Compared with MT, the grain yield of early rice with ST and HT increased by 1 203.3-1 346.7 and 776.7-1 045.4 kg/hm², the grain yield of late rice with ST and HT increased by 2 128.7-2 212.2 and 1 574.2-1 603.9 kg/hm².These indicated that the photosynthetic characteristics and grain yield for early and late rice with different cultivation methods had their own distinct characteristics.Compared with MT, ST and HT had significantly higher grain leaf area ratio of rice and population quality of rice, and improved grain yield and yield components.