氮肥和密度互作对机插超级杂交稻叶型、光合特性及产量的影响

Effects of Interaction between Nitrogen Fertilizer and Planting Density on Leaf Type,Photosynthetic Characteristics and Yield of Mechanical-transplanting Super Hybrid Rice

以超级杂交稻全两优681为材料,探讨不同氮肥用量和密度对江汉平原地区机插超级杂交稻叶型、光合特性及产量的影响。结果表明,氮肥和密度互作对高效叶面积率、净光合速率和气孔导度影响显著,对胞间CO2浓度影响不显著。低氮、低密度有利于高效叶面积率的提高,高氮、低密度有利于净光合速率和气孔导度的提高。氮肥和密度互作对超级杂交稻产量影响显著,产量随着氮肥用量和机插密度的增加而增加,以高氮(250 kg/hm2)+高密度(2.38×105株/hm2)处理产量最高,为9.26 t/hm2,显著高于其他3个处理。氮肥和密度互作主要影响了超级杂交稻的单株穗数、结实率。其中,单株穗数是机插杂交稻超高产的关键,建议江汉平原地区在适宜的氮肥水平下,通过适当增加密度来获得高产。

The effects of different nitrogen fertilizer application amount and transplanting density on the leaf type,photosynthetic characteristic and yield of mechanical-transplanting super rice were studied with Quanliangyou 681 as material. The results showed that the interaction between the planting density and ni-trogen fertilizer significantly influenced the rate of effective leaf area,net photosynthetic rate and stomatal conductance,and did not significantly influenced the intercellular CO2 concentration. The lower planting density and nitrogen fertilizer application amount were beneficial for the increase of effective leaf area rate,lower planting density and higher fertilizer application amount were beneficial for the increase of net photosynthetic rate and stomatal conductance. The interaction between the planting density and nitrogen fertilizer significantly influenced the yield of super hybrid rice,the yield increased with the increase of the planting density and nitrogen fertilizer application amount,the treatment with high fertilizer application amount（250 kg / ha）and high density（2. 38 × 105 plants/ ha） obtained the highest yiled of 9. 26 t/ ha, which significantly higher than the other treatments. The interaction between the planting density and ni-trogen fertilizer mainly influenced the panicles number per plant and setting percentage,and panicles number per plant was crucial for high yield of mechanical-transplanting super hybrid rice,the proper in-crease of transplanting density was the approach to receive high yield under the suitable nitrogen fertilizer application amount in Jianghan Plain.