Sarsina violascens spatial and temporal distributions affected by native vegetation strips in eucalyptus plantations

Abstract: The objective of this work was to evaluate spatial and temporal distributions of Sarsina violascens (Lepidoptera: Noctuidae: Lymantriinae) in two Eucalyptus cloeziana plantations, one with native vegetation strips (WNVS) and another without them (ONVS). Adults were collected with light traps, which were installed: inside an area of native vegetation (Cerrado), 100 m from the edge; at the contact zone between the native vegetation area and the E. cloeziana plantation; inside the E. cloeziana plantation, 250 m from the edge; at the central part of the native vegetation strip, around 500 m from the edge (WNVS) or in the contact zone between two E. cloeziana compartments (ONVS); and inside the E. cloeziana plantation, 500 m from the edge. The number of S. violascens adults collected was 240 in the system WNVS and 1,378 in the system ONVS. The lower number of individuals in the system WNVS was probably due to favored biological control provided by higher species richness with the use of native vegetation strips. These strips, intermingled with E. cloeziana plantations, allow a higher proportion of native forest in the landscape and can help to reduce S. violascens infestations.

摘要：本研究旨在探究两处克洛伊桉（Eucalyptus cloeziana）人工林内紫堇色萨氏蛾（Sarsina violascens，鳞翅目Lepidoptera：夜蛾科Noctuidae：毒蛾亚科Lymantriinae）的时空分布格局，其中一处设置本土植被带（WNVS），另一处未设置该植被带（ONVS）。研究采用诱虫灯采集成虫，诱虫灯布设点位如下：距边缘100米处的塞拉多（Cerrado）原生植被区内；原生植被区与克洛伊桉人工林的交界带；距边缘250米处的克洛伊桉人工林内部；WNVS组中距边缘约500米的本土植被带核心区域，或ONVS组中两片克洛伊桉林分区块的交界带；以及距边缘500米处的克洛伊桉人工林内部。WNVS组共采集到240头紫堇色萨氏蛾成虫，ONVS组则采集到1378头。WNVS组的成虫采集量较低，可能得益于本土植被带带来的更高物种丰富度所提供的更优生物防控服务。这类与克洛伊桉人工林交错配置的植被带，能够提升景观中原生林的占比，进而有助于抑制紫堇色萨氏蛾的虫害发生。