D. S. Khurana

Effect of straw mulching, irrigation and fertilizer nitrogen levels on soil hydrothermal regime, water use and yield of hybrid chilli

In northern India, chilli is transplanted in the hot and dry months of February and March when the crop depends upon irrigation water for canopy establishment. Hybrid chilli may require more irrigation water and fertilizer N due to its higher yield potential but the problem of the depleting groundwater table in the region necessitates developing a technique for reducing water requirement. Rice residue mulching can lower soil temperature and reduce evaporation losses from soil. An experiment was conducted on sandy loam soil for three years to evaluate the effect of rice straw mulch @ 6 Mg ha−1 on yield, fertilizer N and irrigation water requirement of hybrid chilli. Maximum and minimum soil temperatures at 50 mm depth during 2003 were lowered up to 8.9 and 2.2°C, respectively, by rice residue mulching. Mulching improved fresh red chilli yield by 2.4 Mg ha−1 and required 120 mm less irrigation water. Substantial yield increase with mulching may be attributed to favourable soil hydrothermal regime as evident from lower soil temperature, higher profile moisture (12 mm) and 13.5 Mg ha−1 lower weed biomass. Chilli yield obtained with 45 kg N ha−1 with mulch was the same as that of 75 kg N ha−1 without mulch. Ascorbic acid content decreased with lower irrigation frequency but was significantly higher without mulch.

Effect of CIPC [Isopropyl-N(3-chlorophenyl)carbamate] on total nitrogen content and polyphenol oxidase activity in relation to processing of potatoes (Solanum tuberosum L.) stored under different conditions

Two varieties of potatoes viz. Kufri Chandramukhi and Kufri Sindhuri were treated with Isopropyl-N(3-chlorophenyl)carbamate at two different concentrations viz. 4000 and 5000 ppm. The treated potatoes were stored for a period of four months under different storage conditions i.e. room temperature, cold and evaporative cooling chamber storage and analysed for polyphenol oxidase activity, total nitrogen content and quality of dried slices produced from these at different stages of storage. Higher nitrogen content was observed in CIPC treated potatoes as compared to control. Polyphenol oxidase activity decreased more in Kufri Chandramukhi than in Kufri Sindhuri in CIPC treated as well as in control experiments. The changes in nitrogen content and polyphenol oxidase activity were more pronounced in evaporating cooling chamber and in room storage than in the cold storage. The quality of potato slices prepared from both varieties confirmed the superiority of Kufri Chandramukhi over Kufri Sindhuri for processing purposes.

Effect of different weed management practices on growth and yield of brinjal (Solanum melongena L.)

Brinjal (Solanum melongena L.) also known as eggplant or aubergine is an important commercial vegetable crop grown throughout the India mainly by small, marginal and resource-poor farmers. It is the second highest consumed vegetable in India after potato and is considered as poor man’s vegetable. It is quite high in nutritive value and can be well compared with tomato and is consumed as a cooked vegetable in various ways.