Genetic diversity in chestnuts of Kashmir valley Intercropping with legumes makes effective use of land and other resources and results in reduced cost of production. Increased agricultural production through intercropping with minimal cost is need of time to feed increasing population. The reported work evaluates the biological efficiencies and economics of pea, garlic, turnip and cauliflower grown as sole crops and when pea intercropped in garlic, turnip and cauliflower during 2010-12. All the vegetables generally yielded more when grown as single crop compared with when pea was intercropped in these vegetables. In peas in garlic intercropping, pea yield was not significantly affected; however, garlic yield was significantly reduced (65.8%). Pea intercropping in turnip or cauliflower resulted in significantly lower yields of both crops (29.1 and 28.0%, respectively) as compared with their sole cropping. All other characteristics (plant growth and yield components) of all the four crops which indicate biological efficiency generally were greater when grown as single crops and decreased in intercropping combinations. Analysis of intercropping treatments revealed that pea intercropping in turnip resulted in the highest marginal rate of return (8,875%), followed by pea intercropping in cauliflower (6,977%), due to lower input costs incurred per hectare. However, net benefit to the growers was higher (Rs. 327,925) in case of pea intercropping in cauliflower, followed by pea intercropping in garlic (Rs. 213,425). Keywords: Allium sativum, Brassica oleracea var. Botrytis, Brassica rapa, Pisum sativum, Marginal rate of return, intercropping. INTRODUCTION Demand of vegetables is increasing with rapidly growing world population which will become 9 billions in year 2050. There is also large gap between demand and supply of vegetables in Pakistan. Hence, a cropping system that can increase the rate of vegetable production and/or lower the cost of production will provide economical opportunity for farmers. Intercropping has been identified as a promising system that makes effective use of land and other resources (Remison, 1982) like water and soil nutrients and results in reduced cost of production (Bijay et al., 1978). It has also gained wide acceptability among farmers of tropical and sub-tropical countries because of its economic advantages resulting from the symbiotic association of legumes intercropped with other crops (Ahmed and Gunasema, 1979). Intercropping involving legumes has been found to be most useful (Adeniyi, 2011) as it improves soil fertility and gives better yields and economic returns (Lithourgidis et al., 2011). Common beans are poor fixers (less than 56 kg ha -1 per growing season) and fix less than their nitrogen needs. Other grain legumes, such as peas, peanuts, cowpeas, soybeans and faba beans are good nitrogen fixers and can fix all of their nitrogen needs other than that absorbed from the soil. These legumes may fix up to 280 kg N ha -1 and are not usually fertilized (Lindemann and Glover, 2003). Almost all of the fixed nitrogen goes directly into the plant and little leaks into the soil for neighboring non-legume plants. Eventually, nitrogen returns to the soil for following crops when vegetation (roots, leaves, fruits) of the legume dies and decomposes (Lindemann and Glover, 2003; Rahman et al., 2009). Since, excessive use of inorganic fertilizers contribute to environmental damage such as nitrate pollution; legumes grown in intercropping are regarded as an alternative and sustainable way of introducing N into lower input agro- ecosystems (Fustec et al., 2010). The main effect of intercropping is because of more efficient utilization of available resources and increased productivity compared with each sole crop (Hauggaard-Nielsen and Jensen, 2001; Hauggaard-Nielsen et al., 2001; Zhang and Li, 2003; Szumigalski and van Acker, 2006; Dhima et al., 2007; Agegnehu et al., 2008; Launay et al., 2009; Mucheru-Muna et al., 2010; Mao et al., 2012). Yield is increased because growth resources such as light, water and nutrients are more efficiently absorbed and converted to crop biomass by the intercropping over time and space as a result of differences in competitive ability for growth resources between the component crops. This exploits the variation of the mixed crops in characteristics such as rates of canopy development, Pak. J. Agri. Sci., Vol. 50(3), 399-406; 2013 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 http://www.pakjas.com.pk EFFECT OF PEA INTERCROPPING ON BIOLOGICAL EFFICIENCIES AND ECONOMICS OF SOME NON-LEGUME WINTER VEGETABLES Syed Ali Qasim 1 , Muhammad Akbar Anjum 1’* , Sajjad Hussain 1 and Shakeel Ahmad 2 1 Department of Horticulture, Faculty of Agricultural Sciences & Technology, Bahauddin Zakariya University, Multan-60800, Pakistan; 2 Department of Agronomy, Faculty of Agricultural Sciences & Technology, Bahauddin Zakariya University, Multan-60800, Pakistan *Corresponding author’s e.mail: akbaranjum@bzu.edu.pk