Pollen grains are suitable alternative food for rearing the commercially used predatory mite Neoseiulus cucumeris (Acari: Phytoseiidae)

Abstract

The generalist predatory mite, Neoseiulus cucumeris (Oudemans) is one of the most effective natural enemies on many crops in indoor cultivations. As supply of alternative food such as pollen is generally thought to enhance the reproductive and biological control performance of generalist predatory mites, the life table parameters of the predatory mite, N. cucumeris were determined  in laboratory at 25±1°C, 60±5% RH, and a photoperiod of 16:8 (L: D) hours when fed on seven different pollen (almond, bitter orange, maize, date palm, castor bean, sunflower, and bee-collected). Our results indicated that feeding the predator on castor bean, almond, date palm, and sunflower pollen led to better performance in terms of higher oviposition (38.18, 33.53, 32.87, and 29.48 eggs/female, respectively), intrinsic rate of increase (0.146, 0.129, 0.152, and 0.123 day-1, respectively) and net reproductive rate (19.55, 12.58, 14.93, and 14.06 eggs/individual, respectively), and shorter development time (7.08, 7.73, 7.19, and 9.30 days, respectively). Bitter orange and bee-collected pollen were not suitable diets for both development and reproduction of N. cucumeris. The shortest (7.08 days) and longest (16.09 days) development times were observed on castor bean and bee-collected pollen, respectively. Adult longevity varied from 6.88 days on maize to 60.4 days on castor bean pollen. The highest fecundity was obtained on almond, followed by date palm, and castor bean pollen, while feeding on maize pollen did not lead to oviposition. Overall, we found that castor bean along with date palm, almond, and sunflower pollen are suitable diets for large scale rearing of N. cucumeris for subsequent use in biological control of pests in greenhouses.