蚯蚓粪缓解草莓连作土壤障碍的作用

【目的】土壤灭菌处理已成为草莓生产中土传病害综合管理的重要措施,但是土壤灭菌明显抑制了土壤微生物的活性,影响草莓植株的生长。有机肥中含有大量的生物活性物质,尤其是蚯蚓粪。本研究通过观测连作土壤灭菌后施用不同有机肥对草莓植株地上部和地下部的影响,为减缓草莓植株生长的连作障碍提供有机肥选择。【方法】采用温室盆栽草莓模拟试验,首先在去除土壤化感效应影响基础上设置土壤灭菌和正常土壤栽培两个处理,探讨土壤灭菌对草莓植株不同阶段地上部叶片及地下部根系生长影响,在此基础上以相同连作土壤进行另一个盆栽试验,设置不灭菌土壤加无机肥料(LW)、 加牛粪(LN)、 加蚯蚓粪(LQ)处理,灭菌土壤加无机肥料(LMW)、 加牛粪(LMN)、 加蚯蚓粪(LMQ)共6个处理。调查了不同处理开花前苗期草莓植株地上部叶片及地下部根系的生长状况。【结果】土壤灭菌处理较相应未灭菌处理显著抑制了草莓花前幼苗阶段植株地下部的生长(P＜0.05),在果实成熟期、 盛果期及盛果末期植株生长均存在补长效应。土壤灭菌改变了草莓植株地上部和地下部正常的生长发育进程,植株不同发育阶段根冠比发生变化。无论连作土壤灭菌与否,施用无机肥料处理较施用有机肥处理显著抑制了根系生长(P＜0.05)。在不灭菌土壤上,施用蚯蚓粪处理草莓植株根系总长、 根系总表面积、 根尖数及根叉数与施用牛粪处理差异不显著,但灭菌土壤上,施加蚯蚓粪与施加牛粪相比,显著增加了草莓植株根系总长、 根系表面积及根叉数(P＜0.05)。【结论】蚯蚓粪与牛粪和无机肥料相比具有显著的生物活性。在草莓连作土壤灭菌后施用具有生物活性的蚯蚓粪,可以促进根系生长,缓解土壤灭菌对草莓植株生长发育的影响,是值得推荐的有效措施。

Alleviation of vermicompost to obstacle in sterilized continuous cropping soil in strawberry production

【Objectives】 Soil sterilization has been used to deal with the disease obstacles caused by continuous cropping, however, this measurement also causes inhibition to the crop growth in the sterilized soils. Organic manures contain diverse bioactive components, especially bioactive vermicompost. So the effects of vermicompost and cattle manure were compared to provide a base for the choose of correct fertilizer source in strawberry production.【Methods】 Pot strawberry plants in greenhouse were chosen to conduct the experiments. Normal soil was collected from the soil below 20 cm depth in a grain field, and continuous cropping soil was from a strawberry garden where strawberry had been continuously grown for three years. All the two soils were divided into two parts, one part was sterilized and the other not. For the continuous cropping soil either sterilized or not, cattle compost or vermicompost, which was made by feeding earthworms with the cattle compost, was added in ratio of 20% of the soil separately, and NPK compound fertilizer was used as control. The growth of leaves and roots of strawberry plants in different growth stages was measured.【Results】Soil sterilization significantly(P＜0.05)suppressed the growth of roots, especially in seeding stagebefore flowering, and altered root architecture and ratio of shoot to root in all the monitored stages of strawberry plants. In the sterilized continuous cropping soil and normal soil, the addition of compound fertilizer significantly (P＜0.05) inhibited the development of root system, compared to the two compost treatments. There was no significant difference in total root length, root surface area, root tips and root forks between vermicompost and cattle compost treatments in continuous cropping soil, but those in vermicompost treatment were significantly higher than in cattle manure treatment in sterilized continuous cropping soil (P＜0.05).【Conclusions】 Vermicompost shows higher bioactivity than cattle manure in sterilized soils. In sterilized soils, application of vermicompost could significantly stimulate the growth of root system, and form larger shoot and root biomass and good root system of strawberry. So, the application of vermicompost should be recommended for the alleviation of continuous cropping obstacles in strawberry production.