Evolutionary Ecology Group, University of Antwerp, Wilrijk, Belgium.
Research Centre Hoogstraten, Hoogstraten, Belgium.
Pest Manag Sci. 2020 Feb;76(2):676-684. doi: 10.1002/ps.5565. Epub 2019 Aug 25.
Aphids (Hemiptera: Aphididae) are a problematic pest in global sweet pepper cultivation. Control of aphids often relies on insecticides, leading to widespread resistance. Biological control of aphids is mainly based on releasing specialist natural enemies, but they often fail to control outbreaks. Macrolophus pygmaeus Rambur (Hemiptera: Miridae) is a zoophytophagous generalist which attacks several sweet pepper pests, including aphids. Previous research showed that M. pygmaeus is capable of strongly reducing aphid populations in sweet pepper, but complete control was seldom achieved. Sweet pepper plants continue to grow during the season, reaching > 3 m high in Belgian and Dutch greenhouses. Dense foliage and large vertical distance from the flowers to the lower leaves impede the search efficiency of the predator. Leaf pruning may improve aphid predation by M. pygmaeus by increasing the probability of encountering prey.
Four and five treatments (foliage range: 100 cm to full length) respectively were tested in a semi-commercial sweet pepper greenhouse in 2017 and 2018. Aphid populations in pruned treatments grew more slowly than in the control and M. pygmaeus was eventually able to control aphids in all pruned treatments in 2018. There was no difference in aphid control between the pruned treatments. Sweet pepper production was lower in the treatments with the shortest foliage lengths.
Leaf pruning up to 160 or 190 cm foliage length improves aphid control by M. pygmaeus in sweet pepper without affecting production. © 2019 Society of Chemical Industry.
蚜虫（半翅目：蚜科）是全球甜椒种植中的一个严重问题。对蚜虫的控制通常依赖于杀虫剂，导致广泛的抗药性。蚜虫的生物防治主要基于释放专门的天敌，但它们往往无法控制爆发。桃蚜猎蝽（半翅目：猎蝽科）是一种杂食性的肉食性昆虫，可攻击包括蚜虫在内的几种甜椒害虫。先前的研究表明，桃蚜猎蝽能够强烈减少甜椒中的蚜虫种群，但很少能完全控制。甜椒植株在整个生长季节中会继续生长，在比利时和荷兰的温室中可长到超过 3 米高。茂密的枝叶和从花朵到下部叶子的大垂直距离阻碍了捕食者的搜索效率。修剪叶片可能会通过增加捕食者遇到猎物的概率，从而提高桃蚜猎蝽对蚜虫的捕食作用。
在 2017 年和 2018 年，在一个半商业化的甜椒温室中分别测试了四个和五个处理（叶片范围：100 厘米到全长）。修剪处理中的蚜虫种群生长速度比对照和桃蚜猎蝽处理慢，2018 年所有修剪处理中的桃蚜猎蝽最终都能够控制蚜虫。修剪处理之间的蚜虫控制没有差异。叶片最短的处理中甜椒产量较低。
修剪叶片至 160 或 190 厘米的长度可以提高桃蚜猎蝽在甜椒中的蚜虫控制效果，而不影响产量。 © 2019 英国化学学会。
