Abstract

EXTENT OF CROP DAMAGES CAUSED BY A SERIOUS RODENT PEST, THE RATTUS SIKKIMENSIS, IN THE GANGETIC AND NON-GANGETIC PLAINS OF WEST BENGAL, INDIA

Debiprosad Chattopadhyay and Chanchal Kumar Manna*

ABSTRACT

Rodents are the serious pests throughout the world. Every year, rats in Asia consume food crops that could feed 200 million people for an entire year. In the present study four districts, two from the Gangetic plain and two from the non-Gangetic plain of West Bengal were selected. The Gangetic and the non-Gangetic plains were very different to their climatic condition, soil structure and major crop pattern. Naturally the crop production and the extent of damages will be varied due to change in soil structure in these regions. The average temperature of the Gangetic and the non-Gangetic plains were 39 ± 2.74 °C (maximum), 10.7 ± 2.62°C (minimum) and rainfall were, 1339.07 ± 135.92 millimeter and 44.5 ± 0.84°C (maximum), 7.8 ± 0.91°C (minimum), 1266.71 ± 116.85 millimeter respectively. The average pH, clay content and sand percentage were 6.75 ± 0.39, 24.2 ± 0.89 and 33.2 ± 1.35 respectively in the Gangetic plain and 5.93 ± 0.32, 15.3 ± 1.03 and 78 ± 2.14 respectively in the non-Gangetic plain. No such significant differences were observed in the available nitrogen, organic carbon and the phosphate in between the Gangetic and the non-Gangetic plains. Major crops of the Gangetic plain were rice, wheat, gram, mustard, jute, mesta, sugar cane, potato, chilli and ginger, and in the non-Gangetic plain major crops were rice, wheat, maize, mustard oil seed, sugarcane, potato and chilli. Almost all the major crops of both these regions were damaged by rodents and especially the Rattus sikkimensis. It was observed that in comparison to rice much damage was observed in the wheat field. It may be due to their favourite food stuff and a relatively long exposure time and dense biomass.

Keywords: Gangetic, Non - Gangetic, Damage, Climatic condition, Rodent Pest.