Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, 70803, Louisiana, USA.
Sci Rep. 2019 Oct 1;9(1):14037. doi: 10.1038/s41598-019-50354-2.
The effect of soil type on establishment of arbuscular mycorrhizal (AM) fungi, and their effects on plant growth and resistance to rice pests are poorly understood. We investigated the effects of inoculation with AM fungi on rice plants in two different unsterilized field soils under greenhouse and field conditions in two consecutive years in Louisiana, United States. We tested whether inoculation with AM fungi in the two soils changed plant biomass, nutrient concentration, resistance to pests, and yields. Inoculation with a commercial formulation of AM fungi increased root colonization by fungi in all soils, regardless of soil P availability; it also increased densities of root-feeding rice water weevil larvae and growth of leaf-feeding fall armyworm larvae, but these effects were soil-dependent. Inoculation with AM fungi had no effect on N and P concentrations or rice yields. The effect on plant biomass was also soil-dependent. Our study provides evidence for the first time that inoculation with AM fungi can increase colonization of roots of rice plants, but the effects of colonization on resistance to pests and plant biomass appear to be soil dependent. Moreover, the increased susceptibility to pests of rice colonized by AM fungi does not appear to be related to nutrient concentrations.
土壤类型对丛枝菌根（AM）真菌定殖的影响，以及它们对植物生长和抗水稻害虫的影响，人们知之甚少。我们在美国路易斯安那州的温室和田间条件下，连续两年在两种未经消毒的田间土壤中，调查了接种 AM 真菌对水稻植株的影响。我们测试了在两种土壤中接种 AM 真菌是否会改变植物生物量、养分浓度、抗虫性和产量。接种 AM 真菌的商业制剂增加了所有土壤中真菌对根系的定殖，而与土壤磷的有效性无关；它还增加了根食性水稻象鼻虫幼虫和叶食性秋粘虫幼虫的密度，但这些影响取决于土壤。接种 AM 真菌对氮和磷浓度或水稻产量没有影响。对植物生物量的影响也取决于土壤。本研究首次提供证据表明，接种 AM 真菌可以增加水稻植株根系的定殖，但定殖对害虫抗性和植物生物量的影响似乎取决于土壤。此外，AM 真菌定殖的水稻对害虫的敏感性增加似乎与养分浓度无关。
