Nepal is an agrarian country whose population is primarily dependent on agriculture but the contribution to national Gross Domestic Product (GDP) is low as expected. There are many constraints to agricultural crop production and the farmers are facing those problems in their day-to-day lives. Deployment of insecticides and others to mitigate various insects and pests is one of them. Although abundant with locally available plant resources for pest management, farmers, especially in commercial pocket areas, are primarily dependent on conventional pesticides and those chemicals have detrimental effects on human health, including various flora, fauna, and environment. Although the Nepal government has formulated an act and worked on that basis, there is plenty of room to work on. Since farmer knowledge and behavior have a positive impact on reducing the use of conventional insecticides and work on alternative measures for pest management, these sorts of programs should be prioritized by the Government of Nepal and its allied agricultural organizations.

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Cabbage aphid (Brevicoryne brassicae L.) is an important pest of cabbage which reduces the yield and quality of the cabbage head. Farmers haven been using chemical pesticides to manage them but unfortunately these practices are toxic for human health, biodiversity and the environment. The study was conducted to test the efficacy of different bio-rational insecticides along with the chemical insecticide. ‘Green Coronet’ cabbage variety was used and the field experiment was laid out in the experimental farm of Agriculture and Forestry University (AFU), Rampur, Chitwan during the winter season of 2014.  The Experiment was designed in randomized complete block design with having 7 treatments (bio-rational insecticides with chemical and control)  and 3 replications. Plot size was 5.76 m2 (2.4m×2.4m) and spacing of 1 m was maintained between each blocks and plots. Field experiment showed that the highest reduction of cabbage aphid was obtained in Dimethoate (30 EC) treated plot followed by Derisom treated plot. The highest yield of cabbage head was obtained in Dimethoate treated plots (66.47 mt/ha) which was significantly at par with the Derisom (58.79 mt/ ha) treated plots. The yield for other treated plots were 47.60 mt/ha for Margosom, 43.77 mt/ha for Verticillium, 41.63 mt/ ha for Cow urine, 36.77 mt/ ha for Spinosad and control (33.45 mt/ ha) in terms of cabbage head yield. And, at the same time, natural enemies’ population was significantly lower to Dimethoate treated plots compared to bio-rational insecticides. Thus, Derisom (Derris based botanical) might be the best viable alternative in eco-friendly management of cabbage aphid considering cabbage head yield and protection of natural enemies. It was also evident from the research that Margosom (Neem based botanical) was found beneficial not only to conserve natural enemies in the cabbage field but also to minimize cabbage aphid population.

Yellow stem borer, Scirpophaga incertulas (Walker) is monophagous insect pest causing serious damage to rice growers of plain regions of Nepal. This study was done to evaluate the host preference of yellow stem borer to the various genotypes of rice. The research design employed was Randomized Complete Block Design (RCBD) with seven treatments and three replications and done in kharif season of 2021. Rice varieties selected were Sabitri, Sarju 52, US 312, Radha 4, Sawa Mansuli, Silki and Hardinath 3, which are popularly cultivated in Kailali. Sex pheromone trap (scirpolure) was installed to monitor the preference of yellow stem borer for various rice varieties, especially at the panicle initiation stage of rice. Statistical analysis of four weeks data of adult male moths trapped on different cultivars of rice revealed that the yellow stem borer adult moths were highly attracted to the US 312 and less attracted to Sarju 52 and Silki varieties. This research implied that the adoption of popular rice variety Sarju 52 could safeguard the farmers from the notorious pest i.e. yellow stem borer of rice.

Brown marmorated stink bug (BMSB), native to East Asia, is an important agricultural and residential pest of serious global concern. Since its first arrival to Pennsylvania in 1996, it has been dispersed in different states of the USA and continues to invade more. Not only in North America, this insect has invaded Europe, Australia, South America, recently to Africa and newer regions of Asia. These insects are reported to be highly efficient in terms of biological characteristics. Furthermore, due to the absence of effective natural enemies in the newly invaded area, these insect's population is building extensively and causing severe damages to various crops. In the newly invaded areas, control options for these pests are limited till now and growers are mostly dependent on broad spectrum insecticides, which is not only costlier but also have negative consequences to the environment and biodiversity at large. Globalized trade has brought the risk of potential spread of this insect species to the South Asian region from the native areas and newly invaded regions. The regions of sub-tropical climate in South Asia may favor brown marmorated stink bug's growth, development and population buildup and could bear losses to proliferating growers of vegetable and fruit crops. Therefore, it is crucial to monitor the movement and spread of this insect species to South Asia by following strong quarantine measures.