Bekzat Mombayeva

Environmentally sound insect pest management strategies require continuous isolation and identification of effective biocontrol agents from different ecosystems. The quest for fungal isolates that are adapted to high temperatures is particularly significant, as they hold the potential to produce mycoinsecticides that are highly effective in semiarid and arid areas. This study aimed to collect new virulent isolates of entomopathogenic fungi (EPF) from Kazakhstan that show promise for controlling Colorado potato beetle (CPB) populations under arid conditions. Local isolates could be adapted to abiotic and biotic factors in the environment in which they survive. The findings of this study should provide insights into the species of EPF that inhabit a specific arid region of Kazakhstan, examining their traits in the regional climate, soil composition, and biological diversity. Throughout 2023–2024, a series of soil samples was collected from diverse locations within the Turkestan region of southern Kazakhstan for the isolation of EPF. The isolation of EPF was conducted using susceptible larvae of Tenebrio molitor (Coleoptera: Tenebrionidae), a host that does not have specificity for particular species of EPF. Using this insect bait, 41 pure cultures of EPF were isolated from soils in the arid zone of Kazakhstan. Polymerase chain reaction analysis based on the TEF1-α locus showed that all the isolates were indistinguishable from Beauveria bassiana ARSEF 2860 species. However, analysis of the ITS locus revealed two cryptic species: B. bassiana and B. pseudobassiana. For laboratory evaluation of biological activity EPF, the second and third instars of CPB were collected from potato fields in southern Kazakhstan and placed in plastic containers. Test CPB larvae were treated with conidia suspensions at 1 × 10⁷ spores/mL and survival was recorded daily for 3 weeks. The results of the bioassays revealed that all the new Kazakhstan isolates were pathogenic to larvae CPB and caused complete mortality by the end of the 11-day. These results showed that new isolates of EPF were highly virulent against larvae CPB.

As a result of field studies conducted from 2022 to 2024, measures will be proposed to identify pests of rapeseed crops and protect rapeseed crops. The research was carried out at the Berik farm in the T. Ryskulov district of the Zhambyl region. Field experiments on the use of chemical substances and mineral fertilizers against rapeseed pests were conducted in the studied area. Among the soil-dwelling pests, rapeseed crops were affected by chewing worms and wireworms. The identified entomophages included ground beetles, road beetles, soldier beetles, and ladybugs. Ground beetles, soldier beetles, and ladybugs appeared during the budding stage. The following insecticides were tested against crucifer flea beetles: Sumi-Alpha 5% EC (esfenvalerate, 0.3 L/ha), BI-58 EC (dimethoate, 0.8 L/ha), and Achilles EC (lambda-cyhalothrin, 0.2 L/ha). All tested insecticides demonstrated high biological effectiveness. The biological characteristics of key pests and the factors reducing their population were studied. The following types of pests have been registered in rapeseed crops in the Zhambyl region: Psylliodes chrysocephala L., Eurydema omata L., Eurydema oleracea L., Colahellus sophiae Schall., Entomoscelis adonidis Pall., Phaedon cochlearial F., Ceutorchynchus assimilis Pauk., Baris chlorizans userm., Meligethes aeneus F., Perrisia brassiae Winn., Evergestis extimalis Scop.

Мақалада Жетісу облысы жағдайында қантты жүгері агроценозының зиянкесі мақта көбелегінің (Helicoverpaarmigera Hubn.) биоэкологиялық ерекшелігі және олармен күресу шараларытуралы талдау жасалған. Қантты жүгері дақылының агроценозындағы зиянкес мақта көбелегінің биоэкологиялық ерекшелігі зерттеліп, олардың ересек көбелектерінің динамикасын зерттеу үшін әртүрлі феромон тұзақтарының тиімдігілі анықталды. Жетісу облысы аумағында егу уақытына байланысты, мақта көбелегінің (Helicoverpaarmigera Hubn.) қантты жүгері дақылдарын зақымдауы мен оларға зиянкестердің қоныстануы зерттелді. Мақта көбелегінің санының ауытқып отыру себептері, алғашқы ұрпақ имаголарының ұшу уақытын болжаудың ең дәл әдістері анықталды. Сонымен қатар, қантты жүгері дақылына инсектицидтерді қолданып, олардың биологиялық, экономикалық тиімділігі бағаланды. Жүргізілген зерттеулердің нәтижелері негізінде қантты жүгері дақылын себудің оңтайлы мерзімдері мен оларға қарсы күресу шараларын қолданудың да оңтайлы уақыты анықталды. Мақта көбелегінің (Helicoverpa armigera Hubn.) зиянкестерімен күресу үшін Габробракон (Habrobracon hebetor) энтомофагын сынау, ұсақ мөлтекті аудандық тәжірибеде (ауданы 20 м2 ) күресу үшін биопрепараттар: Греен голд, 0,3% мас.э.(0,3%), Биобатурин, с.п. Bacillus thuringiensis 32000 IU/mg және химиялық инсектицидтер: Абалон, 1,8 % к.э. (18г/л), Барин, к.э. (36г/л), Цепеллин, к.э. (100г/л), Тиамамектин, 3,6%, к.э. қолданылып, қорғау шаралары жүргізілді. Сонымен қатар,өндірістік тәжірибеде (аумақ көлемі- 2 га) қантты жүгері егісінде химиялық инсектицидтер сыналды. Қолданған биопрепараттар мен химиялық инсектицидтердің мақта көбелегімен күресу кезіндегі көрсеткен тиімділі бойынша, биопрепараттардың тиімділі төмен болса, ал химиялық инсектицидтердің тиімділігі жоғары тиімділік көрсетіп отыр.

This article presents the results of isolating and identifying EPF species and screening thermotolerant and highly virulent EPF strains that are promising for controlling Colorado potato beetle populations. Soil samples were collected from southern Kazakhstan for the isolation of fungi used in the experiments. Using the insect bait method, 41 isolates of EPF were obtained from the soils of southern Kazakhstan. PCR analysis based on ITS and TEF loci (elongation factor Ef1a) showed that all the isolates belong to the species B. bassiana. However, analysis of the ITS locus revealed two cryptic species: B. bassiana and B. pseudobassiana. No other fungal species were detected, likely due to the insufficient informativeness of the ITS and TEF loci in distinguishing species. Further studies with other loci are required. As a result of selecting natural isolates for virulence and thermotolerance, the following strains were identified: B13, B14, B15, B22, B23, B24, B25, B23-23, Bc4, Bc7, and Bc8. These strains showed high virulence (100% on the 11th day after treatment) and tolerance to suboptimal temperatures (+15°C and +30°C). Therefore, they are considered the most promising for use in the context of climate change. The data suggest that, despite the source of the isolates, EPF have great potential for controlling Colorado potato beetle populations, as the majority of isolates lead to fatal outcomes. Their geographical origin primarily influences their temperature preferences, which negatively affect their effectiveness in field conditions.

В результате полевых исследований, проведенных в пустынных районах Юго-Восточного Казахстана (песчаные, засоленные, каменистые и почвенные пустыни), основу экологической группы составляют дендрофаги - вредители, питающиеся различными органами саксаула, олигофаги, питающиеся корнями и стволами. В зависимости от особенностей питания жесткокрылых было выделено 6 групп питательных сред. По количеству всех зарегистрированных жесткокрылых вредителей различают: ризофагов, филлофагов, гименоантофагов, ксилофагов, карпофагов, лимфофагов. Вредителем, поражающим различные органы саксаула, зарегистрированным в списке, являются жесткокрылые, среди многих видов полифагов и олигофагов. В то время как большинство полифагов (Scarabaeidae, Tenobrionidae, Elateridae, Curculionidae) питаются в основном вегетативными органами (ростками, побега), большинство олигофагов считаются специализированными вредителями. В статье представлена система классификации, распространение, краткая морфология и биоэкологические особенности саксаула, полученные за годы исследований, виды вредителей, принадлежащие к разным родам жесткокрылых вредителей, которые массово встречаются и специализируются на разных стадиях роста.

According to the field of research, there are species of saxaul and pasture plants that feed on vegetative and generative organs and cause significant damage to phytomass and seed yield during mass reproduction. Lepidoptera occupy leading positions as pests of forest, agricultural crops, pasture plants and fruit trees, as well as pests of warehouses. The article provides information on the biological and ecological features of one of them, a pest species, Coleophoridae. In the countries of the former USSR, more than 1,000 species of Coleophoridae are known, including pests of agricultural crops, forest and fruit trees and pasture plants. The following species live in saxaula: Characia haloxyli (Flkv.), Coleophora captiosa (Flkv.), Ionescumia saxauli (Flkv.), Casignotella gallivora (Flkv.), Coleophora galligena, Coleophora calligoni. As a result of taxonomic verification conducted by scientists around the world recently, it was proved that the genus Coleophoridae is divided into 11 genera. As a result of our research conducted in the desert areas of Southeastern Kazakhstan, 2 species of Coleophoridae were found living in the saxaul, which feed mainly on the generative and vegetative organs of the saxaul. Data on the peculiarities of their biological development, food connection and harmfulness have been obtained. Optimal stages of their development have been determined for the phenological development and control of massively occurring species.