施用不同堆肥对小白菜根系生长和氮素吸收的影响

Influence of Different Compost Treatments on Pakchoi's Root Growth and Nitrogen Absorption

通过盆栽试验,研究施用猪粪堆肥、中药渣堆肥和菇渣堆肥对小白菜根系生长、氮素积累量和氮素干物质生产效率的影响。结果表明:(1)各施肥处理小白菜根系鲜(干)重、体积、表面积、平均直径和根系总长高于对照;(2)猪粪堆肥、菇渣堆肥处理小白菜地上部氮素积累量高于对照,中药渣堆肥处理小白菜地上部氮素积累量低于对照;(3)中药渣堆肥处理小白菜氮素干物质生产效率高于对照,猪粪堆肥、菇渣堆肥处理小白菜氮素干物质生产效率低于对照。通过试验发现,猪粪堆肥处理增加氮素供应可以促进小白菜根系生长,增加小白菜地上部氮素积累量,其根系形态指标与氮素积累量相关性较低,氮素干物质生产效率低;含氮量低的菇渣堆肥、中药渣堆肥处理小白菜通过扩大根体积、表面积等来加强对氮素的吸收,根系形态指标与植株氮素积累量有较高的相关性,氮素干物质生产效率高。氮素积累量与氮素干物质生产效率呈极强的负相关。

Through a pot experiment, the research focuses on the influences of treatment with pig manure compost, mushroom residue compost and herb residue compost on pakchoi's root growth, the amounts of accumulated nitrogen and nitrogen dry matter production efficiency. Results show that:(1) Fresh weight(dry), volume, surface area, average diameter and root length of the pakchoi's root in all the fertilizer treatments are higher than matched group;(2) The amounts of accumulated nitrogen of pakchoi's aboveground part treated with pig manure compost, mushroom residue compost are higher than the matched group while that treated with herb residue compost is lower than the matched group;(3) Nitrogen dry matter production efficiency of pakchoi treated with herb residue compost is higher than the matched group while those treated with pig manure compost, mushroom residue compost are higher than matched group. This research shows that treatment with pig manure compost can promote the growth of pakchoi's root, and increase the amounts of accumulated nitrogen in pakchoi's aboveground part. The indexes of root morphology have weak correlation with nitrogen accumulation, and nitrogen dry matter production efficiency is low; Treatments amended with low nitrogen input, like mushroom residue compost and herb residue compost, expand root volume and surface area to promote the absorption of nitrogen. The indexes of root morphology have high correlation with nitrogen accumulation, and nitrogen dry matter production efficiency is high. The nitrogen dry matter production efficiency is significantly negatively correlated with nitrogen accumulation.