Universidade Federal de Minas Gerais - UFMG, Instituto de Ciências Agrárias, Insetário G. W. G. Moraes, Montes Claros, MG, Brasil.
Universidade Federal dos Vales do Jequitinhonha e Mucuri - UFVJM, Departamento de Agronomia, Diamantina, MG, Brasil.
Braz J Biol. 2022 Apr 27;84:e257975. doi: 10.1590/1519-6984.257975. eCollection 2022.
Galling insects are abundant in nature, found in many ecosystems globally, with species attacking plants of economic importance. We studied the effects of free-feeding organisms on the abundance of galling insects on Caryocar brasiliense (Caryocaraceae) trees in the Brazilian Cerrado (Savanna). Percentage of defoliation and the number of phytophagous mites or number of phytophagous Hemiptera correlated negatively with percentage of galled leaves and the parasitoid Eurytoma sp. (Hymenoptera: Eurytomidae) adults, respectively. Percentage of galled leaves and the numbers of Eurytoma sp. adults and phytophagous mites correlated positively with spiders. Numbers of mites and Hemiptera phytophagous correlated positively with those of lady beetles and Sycophila sp. (Hymenoptera: Eurytomidae), respectively. The number of Ablerus magistretti Blanchard (Hymenoptera: Aphelinidae) adults correlated negatively with Sycophila sp. The number of Agistemus sp. (Acari: Stigmaeidae) correlated, negatively and positively, with those of lady beetles and phytophagous mites, respectively. Free-feeding herbivores affected the presence of galling insects (Hymenoptera) on C. brasiliense trees, competing for food and space. The same was observed between two parasitoids of Eurytoma sp. galling insect, which can reduce the natural biological control of this pest.
致瘤昆虫在自然界中大量存在,分布于全球许多生态系统中,有攻击具有经济重要性的植物的物种。我们研究了自由取食生物对巴西塞拉多(热带稀树草原)地区巴西栗树上致瘤昆虫丰度的影响。叶片损失率和植食性螨或植食性半翅目昆虫的数量与瘿叶的百分比分别呈负相关,与寄生蜂 Eurytoma sp.(膜翅目:Eurytomidae)成虫的数量呈负相关。瘿叶的百分比和 Eurytoma sp.成虫和植食性螨的数量与蜘蛛呈正相关。螨和植食性半翅目昆虫的数量与瓢虫和 Sycophila sp.(膜翅目:Eurytomidae)的数量分别呈正相关。Ablerus magistretti Blanchard(膜翅目:Aphelinidae)成虫的数量与 Sycophila sp.呈负相关。Agistemus sp.(蜱螨目:Stigmaeidae)与瓢虫和植食性螨的数量分别呈负相关和正相关。自由取食的草食动物影响了 C. brasiliense 树上致瘤昆虫(膜翅目)的存在,它们争夺食物和空间。两种 Eurytoma sp.的寄生蜂也是如此,这可能会降低这种害虫的自然生物控制。