author(s)
Md. Iftiar Hossain Molla and Krishna Karmakar

abstract
An experiment was carried out at Block Seed Farm, BCKV, Kalyani, West Bengal, during kharif season of 2017 with a view to select the best performing rice lines against the rice sheath mite in relation to the plant morphological characteristics and yield parameters of forty two rice lines. Among these forty two rice lines, twenty two were newly developed tall (T) and sixteen were dwarf (D) rice lines besides there were three tall (Black rice, Masoori and Prakash) and one popular dwarf rice cultivar (IET-4786) was considered for the experiment. The most of the traditional variety was found to be infested by rice sheath mite causing severe yield loss, hence, these newly developed rice lines were evaluated against the mite in comparison to the selected cultivars. The findings revealed that, the population of sheath mite was maximum in the tall line T-1033-1 and dwarf cultivar IET 4786 while it was very low in rice lines Masoori and D-450-1. From this field experiment it is concluded that the rice lines T-226-1 and D-450-1 had the characteristics with good yield performance as well as tolerant to rice sheath mite infestation. So these rice lines can be used for further experiments with a view to commercial purpose.