Background The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a serious pest of solanaceous plant species, mainly Solanum lycopersicum L. The entomopathogenic fungi, an alternative to chemical insecticides, proved to be an efficient biocontrol agent in reducing pest population density. In the present study, an entomopathogenic fungus, Purpureocillium lilacinum isolated from soil was identified based on the morphological and molecular characteristics and its pathogenicity was tested against target pest. Results The micromorphological characters showed variations in growth pattern, shape and colour on different cultural media. For molecular analysis, a phylogenetic tree based on ITS/LSU and ITS/β-tubulin (benA) gene regions was constructed which revealed the isolate (FC18) as P. lilacinum (Thom) Luangsa-ard, Houbraken, Hywel-Jones and Samson (Family: Ophiocordycipitaceae). Further, the pathogenicity of P. lilacinum was tested using different spore concentrations (1 × 108, 1 × 107, 1 × 106, 1 × 105 and 1 × 104 spores/ml) on larval and pupal stages of T. absoluta, which showed a dose-dependent mortality. At the highest concentration (1 × 108 spores/ml), the mean mortality of 92.99, 83.05, 72.0% of second, third and fourth instar was observed, respectively. Pupal mortality also showed significant differences at different spore concentrations. Conclusion Obtained results showed that the virulence of the indigenous strain of P. lilacinum on T. absoluta can be utilized in the field suppression of the pest as a potent biocontrol agent.

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This study on the population dynamites of pod borer Helicoverpa armigera (Hubn.) on soybean revealed that it appeared from 29th Standard meteorological week (SMW) (0.40± 0.10 three leaves/ plant). It increased and reached its peak level of 2.67± 0.17/ 3 leaves/ plant during 33rd SMW. The declining trend was observed and reached 0.60± 0.13/ 3 leaves/ plant during 40th SMW. The peak infestation was 48% during 35th SMW. The incidence exhibited non-significant positive correlation with maximum (r= 0.227) and minimum temperature (r= 0.335) and evening relative humidity (RH) (r=0.315); and a significant positive one with morning RH (r= 0.599) and significant negative one with rainfall (r= -0.42). The sunshine was found to be negatively and non-significantly correlated (r = -0.069).

The present study was conducted in three villages of district Budgam in the union territory of Jammu and Kashmir, to find out how farmers differentiate the quality of soils and to determine the level of concurrence between farmers perception and scientific assessment of soil quality. Five fields in each village were selected and ranked on the basis of soil quality indices computed from the minimum data set of indicators, including plant available nutrients N, P, K, Ca, Mg, S, OC, BD, WHC (water holding capacity), CEC (cation exchange capacity) as well as microbial count. The respondents ranked the same 5 selected fields on the bases of their experience and perceptions of soil quality. The study reveals that 58% of farmers ranked the best soils correctly whereas, the percentage of farmers who ranked 2nd, 3rd, 4th and 5th soils correctly was 40, 30, 40, and 45%, respectively. The study found that a greater number of farmers from the remotest village Dalwash were able to judge the soils properly, thereby indicating more profound knowledge and better cognitive abilities to understand soils in the local context. The results divulged by the current study highlight the remarkable local soil knowledge of the farmers and therefore, linking this knowledge system with scientific concepts would prove valuable for sustained land-use management.

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