Department of Entomology, University of Georgia, Tifton, GA, USA.
Pest Manag Sci. 2010 Oct;66(10):1089-95. doi: 10.1002/ps.1983.
Thrips are the most consistent insect pests of seedling cotton in the southeastern United States, where symptoms can range from leaf curling to stand loss. In a 2 year study, thrips adults and immatures were sampled at 14, 21 and 28 days after planting on cotton planted with a thiamethoxam seed treatment in concert with crimson clover, wheat or rye winter cover crops and conventional or strip tillage to investigate potential differences in thrips infestations.
Densities of adult thrips, primarily Frankliniella fusca (Hinds), peaked on the first sampling date, whereas immature densities peaked on the second sampling date. Regardless of winter cover crop, plots that received strip tillage experienced significantly fewer thrips at each sampling interval. In addition, assessment of percentage ground cover 42 days after planting showed that there was more than twice as much ground cover in the strip-tilled plots compared with conventionally tilled plots. Correlation analyses showed that increased ground cover was inversely related to thrips densities that occurred on all three sampling dates in 2008 and the final sampling date in 2009.
Growers who utilize strip tillage and a winter cover crop can utilize seed treatments for mitigation of early-season thrips infestation.
在东南部的美国，蓟马是棉花幼苗最常见的虫害，其症状可从叶片卷曲到植株死亡不等。在为期两年的研究中，在种植了噻虫嗪种子处理剂的棉花上，于种植后 14、21 和 28 天，对蓟马成虫和若虫进行了取样，同时种植了三叶草、小麦或黑麦冬季覆盖作物以及常规或条播耕作，以调查蓟马侵染的潜在差异。
成虫蓟马（主要是粉虱科的烟粉虱）的密度在第一次取样时达到峰值，而若虫密度在第二次取样时达到峰值。无论冬季覆盖作物如何，接受条播耕作的地块在每个取样间隔的蓟马数量明显较少。此外，种植后 42 天的地面覆盖物评估表明，与常规耕作相比，条播耕作的地块的地面覆盖物多了一倍以上。相关性分析表明，在 2008 年的所有三个取样日期以及 2009 年的最后一个取样日期，地面覆盖物的增加与蓟马密度呈负相关。
使用条播耕作和冬季覆盖作物的种植者可以利用种子处理来减轻早期蓟马侵染。
