SUMMARY :Weed survival in the crop fields cause direct and indirect damage to the crop yield and quality.30-40% yield loss occurs due to weedsbecause they compete with crops for water, nutrients and light.In addition to the above effects, weedsact as one of the most significant sources of insect and mite pests and diseases. Crop debris can harbour a lot of pests, giving them a safe place to wait around before moving into another crop. Weeds provide shelter and food for insect and mite pests and act as a host or alternate hosts for insects. Insects will move easily from weed to crop plants and they act as vectors for various plant diseases in the field.To minimise the incidence of the pests and diseases on the crop, it is essential to keep the weeds under check by adopting the effective weed control methods which include preventive and control methods.Before adopting an appropriate method, it is essential to know about the weed seeds dispersal, mode of propagation, crop-weed competition.Crop production practices should seek to sever the taxonomic association between the crop and the weeds found within the crop, and nearby places they must be eliminated. Particularly important integrated weed management practices including crop rotation, intercropping, flooding, green manuringand reduceduse of chemical herbicides, management of weeds in non-cultivated areas should be followed. Reshma, A., Ushakumari, K. and Rishitha, G. (2017 How to cite this article :

A total of twenty six seedling progenies of elephant foot yam were evaluated for 24 quantitative characters at Horticultural Research Station, Kovvur to determine the pattern of variation, relationship among the individuals and their characteristics. The principal component analysis reduced the data set into seven principal components which explained 84.61% percent towards variability. The first principal component analysis accounted a maximum of 27.3% of the total variation and contributed by discriminating traits of pseudo-stem height, plant height, breadth of largest leaflet, height of corm and thickness of pseudo-stem base. In general, this study reveals the presence of diversity among 26 seedling progenies of elephant foot yam which can give opportunity for genetic improvement for desirable characters.

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India grows the largest number of vegetables in the world. Varied agro climatic conditions in India make it feasible to grow several vegetables round the year. As many as 61 annuals and 4 perennials are grown in India.Being short duration crops, vegetables are more susceptible to extremities in environment. And vegetable production is also not consistent due to weather extremities and diminishing natural resources. In countries like India it is a serious problem in view of large population depending on agriculture, excessive pressure on natural resources and poor cropping mechanisms. Malnutrition in children in India is also increasing alarmingly. Vegetables play an important role in achieving the nutritional security as they encounter the malnutrition problems in India and also serve as a source of income for the small and marginal farmers.The major objectives of reducing malnutrition and alleviating poverty indeveloping countries through improvedand consumption of safe vegetables that involves adaptation of current vegetable cropping systems like, multiple cropping, mixed farming, intercropping, and relay cropping systems. Integration of crop production, different farming systems with suitable soil and water conservation measures lead to sustainable production increase in income levels and towards better livelihoods. Major emphasis should be given on development of diverse technologies for optimization of farm resources, increased economic return and improved sustainability.