Screening of plant protection products against downy mildew on cucumbers (Pseudoperonospora Cubensis (Berkeley & M. A. Curtis) Rostovzev) in cultivation facilities

S. Masheva, N. Velkov, N. Valchev, V. Yankova
Abstract. Screening of plant protection products (PPP) against downy mildew in cucumbers Pseudoperonospora cubensis (Berkeley & M. A. Curtis) Rostovzev was carried out during the period 2006-2011 in the “Maritsa” Vegetable Crops Research Institute, Plovdiv. Their toxicity to the imago of the bioagent Encarsia formosa Gah. were studied. High effectiveness (over 85.00 %) of the PPP with active ingredients: dimethomorph (Zampro SC, Acrobat paplus SC); symoxanil (Korsate Pro WG, Korsate R DF), strobilurins (Eclair 49 WG, Quadris 25 SC) was established. With the lowest effectiveness to the agent of downy mildew is Timorex 66 EC. All studied products are suitable for including in the systems for control of this disease. A non-toxic product to E. formosa is the botanical fungicide Timorex 66 EC, medium toxic products are those containing a.i. strobilurin and propamocarb-hydrochloride. The remaining PPP are slightly or medium toxic to the bioagent. Therefore E. fоrmosa could be applied parallel with slightly toxic fungicides against P. cubensis.

Bioproducts against diseases and pest in tomato production in cultivation facilities

S. Masheva, N. Valchev, V. Yankova

Abstract. Effectiveness of the botanical products for plant protection Timorex 66 EC and Timorex Gold against late blight (Phytophthora infestans) and early blight (Alternaria solani), of the products Pyros, Pyrethrum FS EC and NeemAzal T/S against greenhouse whitefly (Trialeurodes vaporariorum), tobacco thrips (Thrips tabaci) and twospotted spider mite (Tetranychus urticae) on tomato in cultivation facilities was studied in the period 2008-2010. Products included as a standard were: Ridomil Gold MZ 68 WG, Horus Top, Skore 250 EC, Vaztak new 100 EC, Mospilan 20 SP and Omit 57 Е. Timorex Gold 0,75 % demonstrates god effectiveness against late blight (68,66 %) and early blight (59,52 %). Pyros is described with good biological activity against greenhouse whitefly (against adults – 84,36 % and against larvae – 66,75 %). Phytopesticide Pyrethrum FS EC is with high effectiveness (89,29 %) against tobacco thrips while NeemAzal T/S was with good acaricide activity (92,57 %). In the laboratory tests that were conducted for determination of the secondary action of the botanical products was establishes that Timorex 66 EC, Timorex Gold and NeemAzal T/S are slightly toxic to the bioagent Encarsia formosa and they could be applied in the integrated and biological systems for vegetable production.


Toxicity of plant protection products towards the imago of Encarsia Formosa Gah

V. Yankova, S. Masheva, B. Boev, K. Toskov
Abstract. The endoparasite Encarsia formosa Gah. is one of the well-known and frequently used bioagents for control of greenhouse whitefly (Trialeurodes vaporariorum Westw.). The effect of many applied pesticides is negative towards this useful species. Successful combination of chemical products and biological method in the integrated plant protection systems requires recognition of their side-effect toward the useful species. Laboratory tests for establishment of the plant protection product toxicity to the imago of the parasite E. formosa were carried out in the Maritsa Vegetable Crops Research Institute, Plovdiv during the period 2007-2011. The products BioNeem Plus 1.5 ЕC 0.25% (i. a. azadirachtin), Preferal WG 0.1% – 0.2% (Paecilomyces fomoso-roseus), Timorex 66 EC 1.0% (i. a. extract from Malaleuca alternifolia), Rubin 72 WP 0.25% (i. a. metalaxil-mancoceb) are non-toxic to E. formosa parasite. These products could be applied in the integrated plant protection systems. The insecticides Bi 58 0.1% (i. a. dimethoat), Confidor energy OD 0.08% (i. a. imidacloprid+deltametrin) and Decis 2.5 ЕC 0.05% (i. a. deltametrin) that are strongly toxic should be avoided in use of the parasite E. formosa.