Possibilities for integrated control of the cotton bollworm (Helicoverpa armigera Hübner, 1808) in the growing tomato in greenhouses

In recent years, there has been a significant increase in the number of cotton bollworm (Helicoverpa armigera Hb., 1808) due to changing climatic conditions, the covert life cycle of caterpillars and the formation of resistance in the populations to some of the commonly used insecticides. Experiments with tomato variety Pink Rock F1 grown in greenhouses to determine the biological activity of some products for plant protection against cotton bollworm were conducted at the “Maritsa” Vegetable Crops Research Institute – Plovdiv. The bioproducts Rapax, Dipel 2X, Helicovex, Neem Azal T/S and Sineis 480 SC have good effectiveness >77% towards cotton bollworm in the interval 7-14 days after treatment. The tested insecticides Lanate 25 WP, Coragen 20 SC 200 ml/ha, Exalt 25 SC, Voliam Targo 063 SC, Ampligo 150 ZC and Affirm 095 SG show very good biological activity (E>84%) 7-14 days after treatment.

Efficacy of eco-smart insecticides against certain biological stages of jasmine moth, Palpita unionalis Hb. (Lepidoptera: Pyralidae)

The efficacy of six eco-smart insecticides, Dipel 2x 6.4% WP (Bacillus thuringensis AI), Biofly 100% WP (Beauvaria bessiana AI), Radiant 12% SC (Saccharopolyspora spinosa AI), Mectin 1.8% EC (Streptomyces avermitilis AI), Nimbecidine 0.03% EC (Azadirachtin AI) and Bio-Power 50% EC (Beauvaria bessiana AI), were tested against eggs, larvae and pupae of the jasmine moth, Palpita unionalis Hb. and its parasitoid Apanteles syleptae under laboratory conditions. Data indicated that all tested insecticides had ovicidal activity against P. unionalis. Mectin was the most toxic among the tested insecticides against the egg stage, followed by Radiant or Dipel 2x, and their respective values of LC50 were 0.005 cm/l, 0.006 cm/l and 0.055 g/l. Dipel 2x was the most toxic insecticide to the 1st instar larvae of P. unionalis, whereas Mectin was the most toxic to both the 3rd and 5th instar larvae. Also, the results revealed that Mectin was the most effective against the pupal stage, followed descendingly by Radiant and Dipel 2x. The toxicity index values showed a superior efficiency of Mectin at LC50 (100%) against eggs, 3rd and 5th instar larvae, and pupal stage, whereas Dipel 2x showed such superior efficiency at LC50 (100%) only against 1st instar larvae. The results showed that the percents of pupation and emergence of moths were significantly different in all treatments compared to control, while deformed pupae and malformed adults were insignificantly different when fifth instar larvae were treated with the tested insecticides. Moreover, the rate of P. unionalis adult emergence from treated pupae was concentration-dependent and significant differences were found between insecticide treatments and control. Generally, Mectin, Radiant and Dipel 2x caused the highest impacts on adult emergence and malformed adults percentages. Regarding the toxicity of insecticides to the endoparasitoid A. syleptae, the treated cocoons developed to adult stages with no significant differences compared to control. Meanwhile, the longevity of the emerged parasitoid adults did not differ among the insecticides treatments and control.

The Integration Between Trichogramma Evanescens West. (Hymenoptera: Trichogrammatidae) and Selected Bioinsecticides for Controlling the Potato Tuber Moth Phthorimaea Operculella (Zell.) (Lepidoptera: Gelechiidae) of Stored Potatoes

The Integration BetweenTrichogramma EvanescensWest. (Hymenoptera: Trichogrammatidae) and Selected Bioinsecticides for Controlling the Potato Tuber MothPhthorimaea Operculella(Zell.) (Lepidoptera: Gelechiidae) of Stored PotatoesThe efficacy of the egg-egg parasitoidTrichogramma evanescens(Hymenoptera: Trichogrammatidae) and certain bioinsecticides (e.g., Neemix, Virotecto, Agerin, Dipel 2x and Spinosad) for controlling the potato tuber moth (PTM),Phthorimaea operculella(Zeller) (Lepidoptera: Gelechiidae) under storage conditions was studied. Single and combined treatments ofT. evanescensand the bioinsecticides were tested. Neemix and spinosad were evaluated as spray treatments. Virotecto, Agerin and Dipel 2x were evaluated as dust and spray treatments. Data were recorded in terms of rate of infestation, reduction of infestation, number ofP. operculellapupae, and number of mines per 20 tubers as well as percentage of edible parts. Data revealed that the percentage of infestation in the control treatment was as high as in the Neemix treatment being 96.67 and 90% after one and two months of storage, respectively. Obviously, Spinosad and Dipel 2x were the most effective bioinsecticides in reducing tuber infestation and number ofP. operculellarecovered pupae. Virotecto and Agerin reduced rate of infestation and number of recoveredP. operculellapupae over that of the control, but their effect was significantly lower than that of Spinosad or Dipel 2x. Moreover, there were significant differences among treatments in the form of the number ofP. operculellatunnels and percentages of edible parts after two months in storage. Data further indicated that the integration between the tested bioinsecticides andT. evanescensenhanced the control ofP. operculella.Significant differences in percentages of infestation, edible parts, number of recovered pupae as well as number of mines in stored potatoes existed between individual treatments (withoutTrichogramma) and combined treatments.

Apple, Obliquebanded Leafroller Control with Spinosad, Bacillus Thuringiensis, Abamectin and Chlorpyrifos in Spring, 1995

Spinosad, 80% (formulation NAF-127, DowElanco); Bacillus thuringiensis (Bt) (Dipel 2X, Abbott Laboratories), abamectin Agri-Mek 0.15 EC (Merck & Co., Inc.) and chlorpyrifos (Lorsban 4E, DowElanco) were evaluated for their ability to control OBLR larvae of the overwintering generation. The test was conducted in an apple orchard in Mattawa, WA. The trees were 3-yr-old Delicious on dwarfing roots. Treatments were applied to 12-tree plots replicated 5 times in a randomized complete block. All treatments were applied with a handgun sprayer at 300 psi to the point of drip. Application dates were 5 Apr (pink) and 9 May (petal fall). Approximate application timings with regard to plant development stage are shown in the table. The post-treatment evaluation was made on 24 May by a count of the total number of live OBLR larvae on all trees of a treatment replication. Live larvae were collected to observe sublethal effects. Surviving larvae were reared on artificial leafroller diet in 3.25 oz portion cups until death or adult emergence. Any deformities possibly resulting from exposure to an insect growth regulator were recorded. Weather was good, calm winds and moderate temperatures, at the time of applications.