International journal of Agronomy and Plant Production. Vol., 2 (3), 114-134, 2011 Available online at http:// www.victorquestpub.com ISSN XXXXXXXX ©2011 VictorQuest Publications Organic farming of rice (Oryza sativa L.) - wheat (Triticum aestivum L.) cropping system: a review Moola Ram * , Mohammadreza Davari and S. N. Sharma Indian Agricultural Research Institute, New Delhi – 110012 *Corresponding Author Email: mramagro@gmail.com Abstract Sustainability problem caused by factor productivity decline due to indiscriminate use of chemical fertilizers and pesticides in rice-wheat cropping system can be solved with production of the cropping system under organic farming. Organic farming enhances soil organic carbon, available phosphorus content and microbial population / enzymatic activity of soil thus making it sustainable for organic crop production. Use of different organic amendments in combinations and in a cumulative manner can meet the nutrient requirement of organic rice and wheat in rice-wheat cropping system. The main weed control strategies used in organic farming of rice-wheat cropping system is often combine cultural or husbandry techniques with direct mechanical and thermal methods. Pests are generally not a significant problem in organic system, since healthy plants living in good soil with balanced nutrition are better able to resist pest and disease attack. However, commercial production of biopesticides containing different bacteria, fungi and viruses has been undertaken to control certain insects, pests and diseases in organic crop production systems. Owing to positive influence of organic components in rice-wheat cropping system, it is therefore, be assumed that those farmers who adopted organic management practices, found a way to improve the quality of their soil, or at least stemmed the deterioration ensuring productive capacity for future generations. Keywords: Rice, fungi, organic farming, wheat and organic carbon. Introduction The rice (Oryza sativa L.) - wheat (Triticum aestivum L.) cropping system occupies about 28.8 million hectares mainly spread over Asia’s five countries, namely, India, Pakistan, Nepal, Bangladesh and China (Timsinia and Connor, 2001; Prasad, 2005). In India rice-wheat cropping system covers about 12 million hectares spreading over states of Punjab, Haryana, UP, Bihar, West Bengal, Himachal Pradesh, Uttarakhand, Madhya Pradesh and Rajasthan. Rice-wheat cropping system accounts for about one-fourth of total food grain production of South-East Asia (Abrol et al., 1997) and about 31% of the total food grain production of India (Kumar et al., 1998; Prasad, 2005). This signifies the contribution of rice-wheat cropping system in meeting food requirements of the country. The rice-wheat cropping system, which is considered as the backbone of food self- sufficiency, is however facing a sustainability problem due to practices of modern production system with indiscriminate use of chemical fertilizers and pesticides (Nambiar, 1994; Duxbury et al., 2000; Ladha et al., 2000; Yadav et al., 2000; Prasad, 2005). The concerns like declining factor productivity (Biswas and Sharma, 2008; Patil, 2008; Yadav, 1998; Yadav, 2008), depletion of soil organic carbon and mineral nutrients content (Prakash et al., 2008), water logging and salinization, increasing nitrate concentration in well water (Singh et al., 1995) etc are the consequents of modern rice-wheat production system with unbalanced and injudicious use of chemical fertilizers and pesticides. The adverse effects of these chemicals are clearly visible on soil structure, microflora, quality of water, food and fodder. The quality of produce is also deteriorated due to entry of chemical residues in