栽插密度对赣南中低产田区双季早稻产量的影响

摘要

通过对五优157和五优21进行不同栽插密度处理，研究赣南中低产田区双季早稻适宜栽插密度。结果表明：随栽插密度增加，早稻有效穗数和产量增加较为明显。栽插密度13．3 cm ×20．0 cm处理与13．3 cm ×30．0 cm处理相比，有效穗数提高21．7％，产量增加10．6％。较高栽插密度处理，有利于抽穗期后的剑叶光合速率、SPAD值和叶面积指数保持在较高水平，从而增强抽穗后的叶片光合生产能力，提高全生育期干物质生产量，特别是抽穗－成熟期穗部干物质的积累量。该区适宜栽插密度为32．1万～37．5万蔸／hm2。%The double-cropping early rice varieties Wuyou 157 and Wuyou 21 were planted at different densities in middle -yielding and low-yielding fields of southern Jiangxi province , and their appropriate planting densities were studied .The results showed that:along with the increase in planting density , the effective panicle number and yield of early -season rice increased obvi-ously.In comparison with the treatment of planting density 13.3 cm ×30.0 cm, the treatment of planting density 13.3 cm ×20.0 cm enhanced the effective panicle number and yield by 21.7% and 10.6% respectively.The higher planting density treatments were conducive to keeping higher level of photosynthetic rate , SPAD value and leaf area index of flag leaf after heading stage , thus strengthening the photosynthetic production capacity of flag leaf after heading , and enhancing the dry matter production and accumu-lation at whole growth stage , especially the accumulation of dry matter in the spikes from heading stage to maturation stage .The ap-propriate planting density in this area was 321000~375000 clumps per hectare .