Sri Lanka has a tropical climate due to its location. Monsoonal, convectional, cyclonic and orographic are main rainfall types of the country. The country has been involved in agriculture since time ancient, blessed for its tropical climate and fertile soil. (Sangakkara et.al, ud). Paddy is the main crop among other agricultural crops in Sri Lanka. That is because it is the staple food in the country. There are two cropping seasons of paddy as Yala (dry season) and Maha (wet season).
Some 1.8 million people live and 0.77 million hectares of rice fields are cultivated throughout the country (Department of Agriculture, u.d). Paddy cultivation commonly governed by organic farming practices in past. Rice production began to increase in the 1970s with the green revolution by the use of genetically improved varieties, chemical fertilizers and chemical pesticide. At present, high yielding new improved varieties cultivate about 98% of the area from total rice growing areas of Sri Lanka. Those varieties are highly response to inorganic fertilizer and other chemical inputs.
The inorganic fertilizer use in paddy cultivation in Sri Lanka has been expanding since it’s introduction. Paddy contributes the largest part of the inorganic fertilizer use accounting for about 50% of Sri Lanka’s total use of chemical fertilizers. However, the ongoing use of chemical inputs has harmed the environment and human health, negatively affecting agricultural production and reducing the sustainability of agriculture.
Many scientists suggest that organic farming is a suitable alternative to the conventional farming system. However, organic material alone cannot supply enough nutrients to paddy cultivation. Not only that most farmers reluctance to use organic farming due to its use difficulties, low availability and labour intensive practices. Therefore, it is important to introduce sustainable farming practices without reducing paddy yield. This experiment will be conducted to compare soil fertility analysis, soil microbial analysis, and yield parameters analysis among conventional input system (Department of Agriculture recommendation), reduced input system (50% of Department of Agriculture recommendation + compost) and organic system on the purpose of obtaining basic data to develop sustainable cropping approach.
