[Objective] The aim was to identify changes in a nematode community in response to crop rotation and to determine the appropriate catch crop for a greenhouse. [Method] The experiment was carried out in a typical 6-yea...[Objective] The aim was to identify changes in a nematode community in response to crop rotation and to determine the appropriate catch crop for a greenhouse. [Method] The experiment was carried out in a typical 6-year-old greenhouse,in which cucumber crops were cultivated twice each year(in spring and autumn),and catch crops were planted in summer. The total number of nematodes was counted and nematode community indices were calculated after collecting soil samples in different stages. [Result] Total nematode abundance was decreased in the soils of catch crop in contrast with former crops(cucumber crops). The abundance of the nematode community was reduced in the treatment of crop rotation compared to the soils of catch crop. In addition, the number of nematode taxa was significantly reduced by the treatment of crown daisy compared to the treatments of following crops. Crop rotation regulated the functional composition of the nematode community by increasing the omnivores-predators functional group and decreasing the relative abundance of root herbivores. [Conclusion] These results indicate that crop rotation affects the nematode community in abundance, diversity and functional composition of the nematode community and crown daisy can be served as the most appropriate catch crop in the greenhouse.展开更多
The primary objective to these study was to test NPKCaMg-fertilization induced ＂Zn（2＋）＂ bioavailability in triticale rhizosphere soils. Soil and plant samples were taken from experimental sites randomly, and were...The primary objective to these study was to test NPKCaMg-fertilization induced ＂Zn（2＋）＂ bioavailability in triticale rhizosphere soils. Soil and plant samples were taken from experimental sites randomly, and were analysed in laboratory to plant available Zn^2＋） content. Zinc ＂Zn（2＋）＂ concentrations showed a large variability to interactions with soil＇s pH values. It ranged from 0.4 and 1.36 mg kg1. Soil＇s ＂Zn（2＋）＂ contents had been significantly lower than International Soil Limit （ISL） value （70 mg kgl）, consequently. Plant available ＂Zn（2＋）＂ contents from triticale rhizosphere soils in Leaf＋Straw ranged from 10.1 to 38.4 mg kgl, and in Seed from 26.9 to 52.0 mg kg1. ＂Zn（2＋）＂s Actual Translocation Index （ATI） from rhizosphere soils to Leaf＋Straw had as average 23.6, and to grain 43. 1. ＂Zn（2＋）＂ Leaf＋Straw bioacummulation （g hal） had as average 13.4, Grain 23.2, and total （Leaf＋Straw＋Grain） 36.6. ＂Zn（2＋）＂translocation from soils to Leaf＋Straw was 37% lower than to Grain. Ultimately, within the range of experimental conditions tested these results are present that ＂Zn（2＋）＂ tends to accumulate to triticale organs to create the conditions for toxicity effects in Food Chane.展开更多
基金supported by a Key Grant from the Earmarked Fund for Beijing Leaf Vegetables Innovation Team of Modern Agro-industry Technology Research System (blvt-08)the Natural Science Foundation of Beijing (Project 6972014)the National Science Foundation of China (Grant No. 30972034)
文摘[Objective] The aim was to identify changes in a nematode community in response to crop rotation and to determine the appropriate catch crop for a greenhouse. [Method] The experiment was carried out in a typical 6-year-old greenhouse,in which cucumber crops were cultivated twice each year(in spring and autumn),and catch crops were planted in summer. The total number of nematodes was counted and nematode community indices were calculated after collecting soil samples in different stages. [Result] Total nematode abundance was decreased in the soils of catch crop in contrast with former crops(cucumber crops). The abundance of the nematode community was reduced in the treatment of crop rotation compared to the soils of catch crop. In addition, the number of nematode taxa was significantly reduced by the treatment of crown daisy compared to the treatments of following crops. Crop rotation regulated the functional composition of the nematode community by increasing the omnivores-predators functional group and decreasing the relative abundance of root herbivores. [Conclusion] These results indicate that crop rotation affects the nematode community in abundance, diversity and functional composition of the nematode community and crown daisy can be served as the most appropriate catch crop in the greenhouse.
文摘The primary objective to these study was to test NPKCaMg-fertilization induced ＂Zn（2＋）＂ bioavailability in triticale rhizosphere soils. Soil and plant samples were taken from experimental sites randomly, and were analysed in laboratory to plant available Zn^2＋） content. Zinc ＂Zn（2＋）＂ concentrations showed a large variability to interactions with soil＇s pH values. It ranged from 0.4 and 1.36 mg kg1. Soil＇s ＂Zn（2＋）＂ contents had been significantly lower than International Soil Limit （ISL） value （70 mg kgl）, consequently. Plant available ＂Zn（2＋）＂ contents from triticale rhizosphere soils in Leaf＋Straw ranged from 10.1 to 38.4 mg kgl, and in Seed from 26.9 to 52.0 mg kg1. ＂Zn（2＋）＂s Actual Translocation Index （ATI） from rhizosphere soils to Leaf＋Straw had as average 23.6, and to grain 43. 1. ＂Zn（2＋）＂ Leaf＋Straw bioacummulation （g hal） had as average 13.4, Grain 23.2, and total （Leaf＋Straw＋Grain） 36.6. ＂Zn（2＋）＂translocation from soils to Leaf＋Straw was 37% lower than to Grain. Ultimately, within the range of experimental conditions tested these results are present that ＂Zn（2＋）＂ tends to accumulate to triticale organs to create the conditions for toxicity effects in Food Chane.
