Abstract :
An open field was chosen at El Mahala El Kobra district, El Gharbia governorate. An area of about one faddan (about 4200 m2) was cultivated by cantaloupe seed (variety, Egyptian Galia Melon). N. californicus individuals were released in each predator’s area, once in the first half plots and twice in the second half plots (at two weeks intervals), at the rate of 3, 6 and 9 individuals/2plants in the first and second three treatments of once and twice releases, respectively.
A single release of N. californicus provides low reduction for the red spider mites, T. urticae. This unlikely those obtained from the double release which provides preferable results on controlling the red spider mite, T. urticae. On the other hand, one release of the predatory mite, N. californicus with the medium rate (6 predators/ 2 plants) or low rate (3 predators’ 2 plants), as well as releasing the predator two releases with the low rate resulted in low mite reduction.
In conclusion, under the open field conditions, our results showed a preference for utilizing multiple releases of the predatory mite, N. californicus to regulate the populations of T. urticae. Either moderating reduction or not prevent T. urticae from exceeding the economic threshold level.
Keyword :
Neoseiulus californicus; Releasing; biological control; Red spider mite; Tetranychus urticae