Evaluation of Natural and Factitious Food Sources for Pronematus ubiquitus on Tomato Plants

Pronematus ubiquitus (McGregor) is a small iolinid mite that is capable of establishing on tomato plants. Once established, this mite has been shown to control both tomato russet mite, Aculops lycopersici (Tryon) (Acari: Eriophyidae), and tomato powdery mildew (Oidium neolycopersici L. Kiss). In the present study, we explored the effects of a number of alternative food sources on the oviposition rate in the laboratory. First, we assessed the reproduction on food sources that P. ubiquitus can encounter on a tomato crop: tomato pollen and powdery mildew, along with tomato leaf and Typha angustifolia L. In a second laboratory experiment, we evaluated the oviposition rate on two prey mites: the astigmatid Carpoglyphus lactis L. (Acari: Carpoglyphidae) and the tarsonemid Tarsonemus fusarii Cooreman (Acari: Tarsonemidae). Powdery mildew and C. lactis did not support reproduction, whereas tomato pollen and T. fusarii did promote egg laying. However, T. angustifolia pollen resulted in a higher oviposition in both experiments. In a greenhouse trial on individual caged tomato plants, we evaluated the impact of pollen supplementation frequency on the establishment of P. ubiquitus. Here, a pollen addition frequency of every other week was required to allow populations of P. ubiquitus to establish.

Evaluation of Natural and Factitious Food Sources for Pronematus Ubiquitus on Tomato Plants

Pronematus ubiquitus (McGregor) is a small iolinid mite that is capable of establishing on tomato plants. Once established, this mite has been shown to control both tomato russet mite, Aculops lycopersici (Tryon) (Acari: Eriophyidae) and tomato powdery mildew (Oidium neolycopersici L. Kiss). In the present study, we explored the nutritional value of various food sources in the laboratory. First, we assessed the reproduction of two food sources that P. ubiquitus can encounter on a tomato crop: tomato pollen and powdery mildew. In a second laboratory experiment, we evaluated the nutritional value of two types of prey mites: the astigmatid Carpoglyphus lactis L. (Acari: Carpoglyphidae) and the tarsonemid Tarsonemus fusarii (Acari: Tarsonemidae). Powdery mildew and C. lactis did not contribute to the reproduction, whereas tomato pollen and T. fusarii did allow egg-laying. However, Typha angustifolia pollen was a superior food source in both experiments. In a greenhouse trial on individual caged tomato plants, we evaluated the impact of pollen supplementation frequency on establishment of P. ubiquitus. Here, a pollen addition frequency of every other week was required to allow populations of P. ubiquitus to establish.

The evaluation of potato virus Y transfer by some beneficial bugs (Hemiptera: Heteroptera)

Pazyuk IM, Fominykh TS. 2019. The evaluation of potato virus Y transfer by some beneficial bugs (Hemiptera: Heteroptera). Biodiversitas 20: 1222-1227. The predatory bugs Podisus maculiventris, Orius majusculus, Nesidiocoris tenuis, and Macrolophus pygmaeus were commonly used for control of pests in potato meristem culture in greenhouses. In this study, the risk of transmission of potato virus Y (PVY) by entomophagous bugs was estimated in cage experiments. It has been shown that none of the bugs tested was capable of transmitting the PVY. However, N. tenuis and M. pygmaeus have been shown to damage potato seedlings in the absence of animal food (pests or factitious food). The bug N. tenuis caused severer damage to potato plants than did the bug M. pygmaeus. Therefore, we can recommend only P. maculiventris and O. majusculus for pest control in potato meristem culture in greenhouses.

Хищные клопы в системе контроля вирусов на семенном картофеле

В статье рассмотрена возможность выпуска хищных клопов (подизуса, ориуса, незидиокориса и макролофуса) против вредных насекомых-переносчиков вирусных болезней на меристемном картофеле в теплицах. В садковых экспериментах в 2016–2017 годах оценивали вероятность переноса Y-вируса картофеля этими энтомофагами. Опыты показали, что ни один из видов клопов не переносил Y-вирус. Однако было выявлено, что незидиокорис и макролофус повреждали рассаду картофеля в отсутствии животной пищи (вредителей, подкормки). В связи с этим для биологической защиты меристемного картофеля от вредителей можно рекомендовать только клопов подизуса и ориуса.The predatory bugs Podisus maculiventris, Orius majusculus, Nesidiocoris tenuis and Macrolophus pygmaeus were tested for control of pests in potato meristem culture in greenhouses. The risk of Y potato virus transmission by these entomophagous bugs was estimated in cage experiments in years 2016–2017. It has been shown that none of the bugs tested was capable of transmitting the Y-virus. However, N. tenuis and M. pygmaeus have been shown to damage potato seedlings in the absence of animal food (pests or factitious food). Therefore, we can recommend only P. maculiventris and O. majusculus for pest control in potato meristem culture in greenhouses.