London Howard, Saville David J, Merfield Charles N, Olaniyan Oluwashola, Wratten Stephen D
Bio-Protection Research Centre, Lincoln University, Lincoln, New Zealand.
National Agricultural Research and Extension Institute, Mon Repos, East Coast Demerara, Guyana.
PeerJ. 2020 Aug 7;8:e9317. doi: 10.7717/peerj.9317. eCollection 2020.
In Central and North America, Australia and New Zealand, potato () crops are attacked by , the tomato potato psyllid (TPP). 'Mesh crop covers' which are used in Europe and Israel to protect crops from insect pests, have been used experimentally in New Zealand for TPP control. While the covers have been effective for TPP management, the green peach aphid (GPA, ) has been found in large numbers under the mesh crop covers. This study investigated the ability of the GPA to penetrate different mesh hole sizes. Experiments using four sizes (0.15 × 0.15, 0.15 × 0.35, 0.3 × 0.3 and 0.6 × 0.6 mm) were carried out under laboratory conditions to investigate: (i) which mesh hole size provided the most effective barrier to GPA; (ii) which morph of adult aphids (apterous or alate) and/or their progeny could breach the mesh crop cover; (iii) would leaves touching the underside of the cover, as opposed to having a gap between leaf and the mesh, increase the number of aphids breaching the mesh; and (iv) could adults feed on leaves touching the cover by putting only their heads and/or stylets through it? No adult aphids, either alate or apterous, penetrated the mesh crop cover; only nymphs did this, the majority being the progeny of alate adults. Nymphs of the smaller alatae aphids penetrated the three coarsest mesh sizes; nymphs of the larger apterae penetrated the two coarsest sizes, but no nymphs penetrated the smallest mesh size. There was no statistical difference in the number of aphids breaching the mesh crop cover when the leaflets touched its underside compared to when there was a gap between leaf and mesh crop cover. Adults did not feed through the mesh crop cover, though they may have been able to sense the potato leaflet using visual and/or olfactory cues and produce nymphs as a result. As these covers are highly effective for managing TPP on field potatoes, modifications of this protocol are required to make it effective against aphids as well as TPP.
在中美洲、北美洲、澳大利亚和新西兰，马铃薯作物受到番茄马铃薯木虱（TPP）的侵害。欧洲和以色列用于保护作物免受害虫侵害的“防虫网作物覆盖物”已在新西兰进行了控制番茄马铃薯木虱的试验。虽然这些覆盖物对控制番茄马铃薯木虱有效，但在防虫网作物覆盖物下发现了大量的桃蚜（GPA）。本研究调查了桃蚜穿透不同网孔尺寸的能力。在实验室条件下使用四种尺寸（0.15×0.15、0.15×0.35、0.3×0.3和0.6×0.6毫米）进行实验，以研究：（i）哪种网孔尺寸对桃蚜提供了最有效的屏障；（ii）哪种形态的成年蚜虫（无翅或有翅）和/或它们的后代能够突破防虫网作物覆盖物；（iii）与叶片和网之间有间隙相比，叶片接触覆盖物下侧是否会增加突破网的蚜虫数量；以及（iv）成虫是否可以仅将头部和/或口针穿过覆盖物来取食接触覆盖物的叶片？没有成年蚜虫，无论是有翅的还是无翅的，能够穿透防虫网作物覆盖物；只有若虫能做到这一点，大多数是有翅成年蚜虫的后代。较小的有翅蚜虫若虫能够穿透三种最粗的网孔尺寸；较大的无翅蚜虫若虫能够穿透两种最粗尺寸，但没有若虫能够穿透最小的网孔尺寸。与叶片和防虫网作物覆盖物之间有间隙相比，当小叶接触其下侧时，突破防虫网作物覆盖物的蚜虫数量没有统计学差异。成虫不会通过防虫网作物覆盖物取食，尽管它们可能能够利用视觉和/或嗅觉线索感知马铃薯小叶并因此产生若虫。由于这些覆盖物对田间马铃薯上的番茄马铃薯木虱管理非常有效，因此需要对该方案进行修改，使其对蚜虫和番茄马铃薯木虱都有效。
