On the Occurrence and Impact of Paddy Pest and Diseases in the Sundarban Region of West Bengal and their Management Practices

Aman paddy is grown in an area of 23050 hectare (2005-06) in Basanti Block of Sundarban region of West Bengal. The production and productivity of Aman paddy in this block were 52471.57 MT (Clean rice) and 2267.55 kg/hectare (Clean rice) respectively. This may be hampered by several factors like pests and diseases. During the Aman season of paddy from July to December, 2006 at Basanti Block of Sundarban region of West Bengal, India surveys were undertaken at an interval of 7 days and data pertaining to the nature of damage of Aman paddy were recorded during each survey trip. During investigation, it has been observed that paddy was mostly affected with one pest (rice leaf folder), one fvmgal disease (sheath blight), one bacterial disease (BLB) and zinc deficiency. Rice leaf folder is a lepidopteran pest of paddy (Atwal and Dhaliwal, 2002). Sheath blight is a fungal disease of paddy (Singh, 2005). Heavy rainfall and water stagnation may cause zinc deficiency of paddy (Gour ct ai, 1999). It is probable that heavy rainfall of 131.9 mm, 110.7 mm and 88.3 mm on 21.09.06, 22.09.06 and 23.09.06 respectively may provide a favourable condition for these pest and disease infestations. It seems that concentration of rainfall at the tillering stage may enhance the infestation of those pests and diseases.