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Sarwar M.,Nuclear Institute of Agriculture | Sarwar M.,Chinese Academy of Agricultural Sciences
International Journal of Pest Management

The food diversification strategy that can offer suitable nutrients as a diet for the natural enemies may possibly help to decrease pest populations by boosting the efficiency of predators. Therefore, my objective was to evaluate the effects of plant and animal diets on biological parameters of the phytoseiid mite Neoseiulus cucumeris (Oudemans). This predator that is a natural enemy of mites was reared on plant pollens (maize (Zea mays L.), sweet pepper (Capsicum annuum L.), mungbean (Vigna radiata L.), cucumber (Cucumis sativus L.), tomato (Lycopersicon esculentum Mill.), and rose (Rosa multiflora Thunb.), offered alone, and in combination with the prey mite Tyrophagus putrescentiae (Schrank). Results showed that N. cucumeris fed, developed and reproduced better when it was provided with plant and animal diets together, compared to pollens offered alone. The predator showed the most efficient capability for completion of life parameters (development, survival, fecundity, oviposition, longevity and instantaneous rate of increase) with maize and mungbean ingested pollens in combination with T. putrescentiae. The least competency was observed on cucumber and rose pollens used separately. The lowest developmental time of the predator from neonate larva to adult emergence, the highest immature survivorship, higher fecundity, long oviposition period, and the highest adult female's life span were observed when offered maize pollens along with T. putrescentiae compared to other treatments. Accordingly, the instantaneous rate of population increase (ri) day−1 was surpassed by N. cucumeris for the combination of pollen and T. putrescentiae diets than pollens utilized alone. It is determined that N. cucumeris can reproduce and develop more successfully on a food complex consisting of pollen and animal diets than any single diet. These findings reveal that pollen can be used by N. cucumeris as a suitable alternative food in periods when prey in the field is sparse or absent. Moreover, such propensity of predators to feed on food from plant origin increases their survival during periods when prey is locally scarce, but natural enemies might occur at the expense of an ability to utilize food as efficiently as specialized predators to boost the management strategies of pest species in field's ecosystem. © 2016 Taylor & Francis Source

Imtiaz M.,Nuclear Institute of Agriculture | Rashid A.,HQ Inc
Pakistan Journal of Botany

The soils in Pakistan across 22 Mha cultivated area are predominantly alluvial and loessal, alkaline in pH, calcareous and low in organic matter. These factors are mainly responsible for nutrient fixation in soil and low availability to plants. Zinc (Zn) deficiency in Pakistan was the first micronutrient disorder recognised in early 1970s as a cause of hadda disease in rice. After identification of Zn deficiency, extensive research has been carried out during last four decades on micronutrient deficiencies in soils and their drastic effects on crops. Subsequently, field-scale deficiencies of zinc (Zn) boron (B) and iron (Fe) have been established in many field and horticultural crops. The most widespread deficiency is of Zn as 70% of the soils of Pakistan are Zn deficient and observed in rice, wheat, cotton, maize, sunflower, sugarcane, brassica, potato and in many other crops along with citrus and deciduous fruits. Boron deficiency is another major nutritional disorder which severely affects rice, cotton, wheat, sugarbeet, peanut, citrus and deciduous fruits. The third field-scale disorder is Fe chlorosis which has been exhibited in peanut, chickpea, cotton, citrus, ornamentals and many tree species. Copper (Cu) and manganese (Mn) deficiencies are of localized occurrence. The mineral elements like Zn, Fe and Cu are as crucial for human health as organic compounds such as carbohydrates, fats, protein and vitamins. The daily dietary intake of young adult ranges from 10-60 mg for Fe, 2-3 mg for Cu and 15 mg for Zn. Intake less than these values can cause slow physiological processes. These micronutrients deficiencies in soil are not only hampering the crop productivity but also are deteriorating produce quality. High consumption of cereal based foods with low contents of micronutrients is causing health hazards in humans. The contents of micronutrients in food can be elevated either by supplementation, fortification or by agricultural strategies i.e., biofortification and application of micronutrients containing fertilizers. Food fortification and supplementation are too expensive, not practical to be applied on large scale and not easily accessible to poor masses. The development of micronutrient efficient genotypes can be a successive tool to overcome the micronutrient disorders in soil and for improvement in human health. However, the harvesting of micronutrient enriched grains from field would mine out more micronutrients. The cultivation of these genotypes can be integrated with the application of micronutrients containing fertilizers. Addition of such fertilizers will not only correct the deficiencies but also improve the fruit size and quality of crops. In general, 2-5 kg Zn ha-1 may be adequate for improved crop production, however, soil applied Fe is generally ineffective except for Fe-sequestrine. Repeated sprays of Ferrous sulphate (FeSO4) or chelated Fe cure the chlorosis and improve the quality of food stuff. However, despite being highly cost effective, currently micronutrient use is negligible. Source

Biological control of the spider mite Tetranychus cinnabarinus (Boisduval) (Tetranychidae) in an open-field cotton crop (Gossypium hirsutum L.) by releasing the predatory mite Neoseiulus pseudolongispinosus (Xin, Liang and Ke) (Phytoseiidae) was investigated. The objectives were to determine the predatory efficiency of N. pseudolongispinosus released during different growth stages of the cotton and the different numbers of plants treated. The factors evaluated were release of predatory mites at a constant rate of five predators per plant using different plant numbers of cotton (every plant or every second or third plant treated) and timing of predator release (early, middle and late season releases). All predator released treatments were compared with a " no predator released" (control) trial. Based on treatment applications, the experimental data collected from biologically managed cotton fields and the untreated control showed significant differences in population densities of pest and predatory mites. Overall, the combined populations of both mites were not significantly different during early and mid-season releases, but varied significantly from late releases of predacious mite. The results also showed that populations of both pests and predators were not significantly different when each cotton plant and every second plant was treated with predator but differed significantly when every third plant was treated, where increased numbers of T. cinnabarinus and decreased N. pseudolongispinosus were observed. Consequently, field release of the predaceous mite N. pseudolongispinosus to reduce the incidence of T. cinnabarinus at an early growth stage of cotton is a potentially useful pest management strategy if every plant is treated with predator. © 2012 Elsevier Inc.. Source

Sarwar M.,Nuclear Institute of Agriculture | Sarwar M.,Chinese Academy of Agricultural Sciences
African Entomology

Knowledge of the arthropod complex associated with any crop is essential for developing pest control strategies. Bt (GK-12, Lu-23 and SGK-321) and non-Bt (Zhong-12, Shiyuan-321 and Simian-3) cotton varieties were used for assessing differences in harbouring populations of the carmine spider mite Tetranychus cinnabarinus (Boisduval) and predatory mite Neoseiulus cucumeris (Oudemans). Two Bt cotton varieties GK-12 and Lu-23, and two non-Bt varieties Zhong-12 and Simian-3 appeared more supportive for maintaining T. cinnabarinus, whereas, SGK-321 (Bt) and Shiyuan-321 (non-Bt) clearly showed reduced pest susceptibility, but efficient in maintaining N. cucumeris population. Throughout the study period, the densities of T. cinnabarinus remained higher (1.77 and 1.40 per leaf) in Bt than non-Bt varieties following insecticides application against the cotton pest complex. The beneficial mite N. cucumeris remained active in both Bt and non-Bt varieties, but Bt cotton had slightly higher numbers of the predator (0.58 per leaf) than non-Bt cotton (0.40 per leaf). Consequently, there were no great impacts on the predatory natural enemy associated with Bt cotton and the predator population in Bt fields was not negatively affected in comparison with conventional cotton. All tested varieties of cotton significantly differed in relation to their morphological characteristics. Of the different factors found to affect the populations of predacious and phytophagous mites, in general, the trichome density on the lower surface of the leaf, leaf thickness and plant height had positive relations with arthropod abundance. Our results showed that SGK-321 (Bt) and Shiyuan-321 (non-Bt) could be recommended for use in creating new resistant cotton varieties as a component of an integrated pest management strategy. Hence, the differences in the response of pest and predator to host plant and leaf architectures should be considered to enhance their roles in biological control strategy. Source

The bruchid, Callosobruchus analis L., is a common storage insect pest of leguminous pulses including lentil (Lens culinaris Medikus). This study was conducted to document relative resistance and susceptibility differences among the eight lentil genotypes against C. analis. Feeding preference, weight lost after feeding, frass weight obtained, reproduction and development time of the bruchid pest, thickness of the outer seed coat and percentage germination were measured to determine the reaction of lentil genotypes. The results showed that none of the genotypes screened was completely free from bruchid infestation. Seeds of genotype AEL-49/20 were least infested and displayed relatively tolerant response; conversely, genotype AEL-23/40 harboured the maximum infestation and was highly susceptible. The remaining six genotypes, Matiary-S, AEL-57/50, M-85, ICARDA-8, AEL-28/40 and M-93 were categorized as intermediate (moderate resistant or moderate susceptible) to the attack of bruchids. Significant (P ≤ 0.05) variations existed among the lentil genotypes with respect to seed coat thickness (from 19 to 39 m), playing an important role in imparting resistance. Germination test of tolerant genotype AEL-49/20 showed 91 % emergence potential. The results emphasize the importance of resistance development to maximize the protection of L. culinaris against C. analis. Source

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