土壤学报2017，Vol.54Issue(2)：493-502,10.DOI:10.11766/trxb201605110159
地上和地下植食者互作对水稻氮分配及土壤活性氮的影响
Effects of Interactions of Above-and Below-ground Herbivores on Nitrogen Distribution in Rice Plant and Labile Nitrogen in Soil
摘要
Abstract
[Objective] Interactions between aboveground and belowground herbivores sharing the same host plantare regarded as the basic linkage between aboveground and belowground ecosystems,though they are separated in space.Much work has been done demonstrating that soil nitrogen availability affects the herbivores via plant by regulating chemical composition,such as nitrogen content of the plant.However,little has been reported on effects of the interactions between the two groups of herbivores on soil nitrogen.In this paper,a microcosm experiment was designed to investigate effects of the interactions between the herbivores on nitrogen distribution in the plant and labile nitrogen (microbial biomass nitrogen,dissolved organic nitrogen,ammonium nitrogen and nitrate nitrogen) in the soil.[Method] In this study,Nilaparvata lugens and Hirschmanniella oryzae were selected as representative of the two groups,aboveground and belowground herbivores,respectively,and a pot experiment was designed to have two rates of Nilaparvata lugens,(zero or eight individuals per plant),and two rates of Hirschmanniella oryzae (zero or 500 individuals per pot),totaling four treatments and four replicates for each treatment.The soil used in the pot was first sterilized under 121℃ to kill all the native nematodes,and then was inoculated with the soil bacterial suspension prepared out of the original soil that had been deprived of soil nematodes,and put into a dark incubator for 60 days of incubation under indoor temperature to restore and stabilize microbial communities in the soil.Rice seedlings were transplanted into the pots after 30 days of seedling nursing in nutrient solution.Hirschmanniella oryzae and Nilaparvata lugens was inoculated separately on the fifteenth and twenty fifth day after rice seedlings were transplanted.Ten days after the inoculation of Nilaparvata lugens,samples of the plants and soil were collected.Plant samples were separated into shoot and root for measurement of biomass and nitrogen content,separately.Soil samples were analyzed,separately,for microbial biomass nitrogen,dissolved organic nitrogen,ammonium nitrogen and nitrate nitrogen.[Result] Results showed that Nilaparvata lugens and Hirschmanniella oryzae negatively affected each other.Nilaparvata lugens tended to decrease shoot biomass,but did not affect much root biomass,while Hirschmanniella oryzae significantly reduced shoot and root biomass (p ＜ 0.05).Nilaparvata lugens showed no significant effect on shoot and root nitrogen content,while Hirschmanniella oryzae significantly reduced root nitrogen content (p＜ 0.05),though they did not affect much shoot nitrogen content.Significantly interactive effects of aboveground and belowground herbivores on soil labile nitrogen were observed.In the absence of Hirschmanniella oryzae,Nilaparvata lugens significantly increased the content of microbial biomass nitrogen (p ＜ 0.05) and decreased nitrate content significantly (p ＜ 0.05),but did not have much effect on dissolved organic nitrogen and ammonium nitrogen,whereas in the presence of Hirschmanniella oryzae,they did not affect the content of soil labile nitrogen significantly.On the other hand,Hirschmanniella oryzae significantly and positively affected the content of microbial biomass nitrogen and total soil labile nitrogen (p ＜ 0.05).[Conclusion] To sum up,the effects of the interactive suppressions between the aboveground and belowground herbivores on nitrogen content in shoot and root of the rice plants and on soil labile nitrogen are rather complicated.Moreover,compared with Nilaparvata lugens,Hirschmanniella oryzae tends to increase total soil labile nitrogen,which may in turn improve N-transformation-related ecological functions of the soil.关键词
褐飞虱/潜根线虫/氮分配/微生物生物量氮/可溶性有机氮/矿质氮Key words
Nilaparvata lugens/Hirschmanniella oryzae/Nitrogen allocation/Microbial biomass nitrogen/Dissolved organic nitrogen/Inorganic nitrogen分类
农业科技引用本文复制引用
郭瑞华,罗琌,张腾昊,刘满强,陈小云,胡锋..地上和地下植食者互作对水稻氮分配及土壤活性氮的影响[J].土壤学报,2017,54(2):493-502,10.基金项目
国家自然科学基金项目(31170487)和江苏高校优势学科建设工程(PAPD)资助 Supported by the National Natural Science Foundation of China(No.31170487) and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PADA) （31170487）
