单粒精播对花生根系生长、根冠比和产量的影响

以大粒型花生品种花育22为试验材料，设每公顷19.5万穴(S1)和22.5万穴(S2) 2个单粒播处理，双粒穴播每公顷15万穴处理为对照进行大田试验，对比单粒精播与双粒穴播对花生耕层根系生长动态、根冠比和产量的影响差异。与对照相比，单粒精播S1处理在开花后50~70 d的根系形态指标和干物质积累动态明显改善，耕层根系长度、体积和吸收面积在0.05水平上显著增加，根系干物质积累量(DMA)和积累速率(DMAR)也明显提高；S1和S2处理开花后40~70 d根冠比明显提高，并保证冠层和荚果较高的DMA和DMAR，通过提高单株生产力，实现群体增产，其中S1处理为佳，可在节种35%的前提下，增产7.98%~8.38%，增产效果显著。本研究说明单粒精播可保证花生根系相对较强的生长优势，协调根冠比，壮个体，强群体，充分发挥单株生产潜力，实现花生高产。

Effects of Single-seed Sowing on Root Growth,Root-shoot Ratio and Yield in Peanut (Arachis hypogaca L.)

Peanut cultivar Huayu 22 was used to study the differences between single-seed sowing and double-seed sowing modes on root growth, root and shoot relationship, and yield under corresponding planting density. The two single-seed sowing treatments were 195 000 holes per hectare (S1) and 225 000 holes per hectare (S2), respectively with the double-seed sowing (150 000 holes per hectare) as control. During the growth period, dry weights, length, volume and absorption area of the root under three treatments increased and reached the maximum at 40–50 days after flowering, and then decreased. The average root diameter decreased and reached the minimum at 50–60 days after flowering, and then increased. The dry weight of aboveground part and pod increased while the root-shoot ratio decreased continuously. S1 and S2 treatments could improve dry weight of the seedlings, the length, the volume, the absorption area of the roots and the root-shoot ratio, and reduce average root diameter during the whole growth period, especially at the late growth period. Additionally, S1 treatment saved 35% sowing seeds and improved peanut yield by 7.98–8.38%. These results indicated that single-seed sowing could improve peanut yield through guaranteeing relatively stronger root growth predominance, regulating root-shoot ratio, and increasing the productivity potential for each seedling.