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The maize weevil Sitophilus zeamais Motschulsky (Coleoptera:Curculionidae) is an important pest of maize in storage in term of losses caused in food quality and quantity in Nepal. Attempt made to review bionomics and management practices of this pest gleaning published literatures/papers on national and international journals, proceedings, reports, newsletter and books. The paper discusses on nomenclature, morphology, distribution, biology and ecology of maize weevil and provides prospect of using various physical, sanitary, cultural, botanical, biological and chemical control measures to manage weevil. This information is useful to personnel involved on agricultural research and development for developing location specific integrated pest management approach of this pest. Finally, it also shows importance of farmers’ awareness on pest biology and ecology, appropriate maize harvesting time, storage structures and post-harvest handling practices to reduce losses in maize storage.

Farmers in the mid-hills of Nepal have a mix of rainfed land on which millet is grown in relay after maize (maize/millet), and irrigated land on which wheat is grown sequentially after rice (wheat±rice). Double cropping is the norm but the diminishing quantities of organic materials, coupled with the trend towards increased use of inorganic fertilizers, have raised questions about the long-term productivity and sustainability of the cropping systems. The aim of this work was to examine the long-term eects (eight years) on grain yield of additions of manure and fertilizer either singly or in combination. Maize/millet and wheat±rice rotations were established on a Dystochrept at Pakhribas Agricultural Centre at about 1450 m altitude. Manure and fertilizer applications were applied to the maize (eight combinations in May) and the wheat (dierent rates in seven combinations in November) every year with the succeeding crops (millet and rice) utilizing residual nutrients. Yields of maize, millet and rice were greater when manure rather than fertilizer was applied but yields of wheat were less. The combined application of manure and fertilizer signi®cantly increased yields of maize and wheat compared with applications of either manure or fertilizer alone. However, for the subsequent crops (millet and rice) there was either a small residual bene®t of the combined application when compared with fertilizer alone, or no bene®t when compared with manure alone. Overall, the combined application increased total grain yields by about 35% in the maize/millet rotation and by 16% in the wheat±rice rotation. There was no trend in yields in response to treatment with time.

Nepalese hillside terraces are classified into two broad groups, sloping or bari terraces which are only rainfed, and level or khet terraces which are commonly flood irrigated but may also be rainfed. Although such terraces may be adjacent, the process of irrigation by flooding and puddling changes the pattern of variability both within and between terraces. Data collected from Pakhribas Agricultural Centre, Dhankuta, Nepal, were used to describe this variability. The variability is manifest not only in the soil characteristics of the two terrace types, with khet terraces being more uniform than bari terraces both within and between terraces, but also in the variability of field experiments on the two terrace types. However, both terrace types exhibit similar patterns of variability which influence the design of experiments. These include the following: a gradient between the terrace riser and wall which is generally more important than gradients along the terrace, variability within terraces which can preclude the assumption that plots on the same terrace are similar, and variability between terraces which requires experimental units in the same block to be assigned to the same terrace.

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