George Thomas, CRenu, SKAU2020-11-132020-11-131999171620https://krishikosh.egranth.ac.in/handle/1/5810155009MScSacciolepis interrupta (Willd.) Stapf. is a serious weed opthe semi dry rice in Kerala. An investigation focussing on the emergence pattern and growth characteristics of Sacciolepis and its management were undertaken at the Agricultural Research Station, Mannuthy during the early Kharif of 1999. Sacciolepis interrupta was found to emerge during the first few weeks after the initial ploughing followed by pre-monsoon showers. Majority of the weed seedlings (87%) emerged during the first two weeks. The emergence pattern supports the possibility of practicing a stale seed bed. in the management of the weed. Seeds collected during July 1998 remained dormant for initial six to seven months. The seed germination commenced by the month of March and attained a peak during June and July. The study on the competitiveness of Sacciolepis interrupta modified by stale seed bed technique was conducted during the first crop season using split plot arrangement in randomised block design (early Kharif) of 1999. The study revealed that competition from Sacciolepis alone could reduce the rice grain yield by 50.1 per cent. The Sacciolepis compete with the crop and reduced the height, LAI, tiller production and biomass production of the crop. Adoption of stale seed bed method reduced the competition from all weeds including Sacciolepis. Stale seed bed with paraquat application was found to be better than stale seed with hoeing. Application of oxyfluorfen @ 0.15 kg ai ha-1 as preemergence spray though reduced the problem of Sacciolepis in the semi-dry rice, could not prevent germination of other weeds beyond 15 DAS. However, as preemergence application of oxyflourfen prevented germination of all type of weeds in the beginning, it could save one hand weeding. From the study, it could be concluded that the practice of stale seed bed technique is an efficient tool for the management of Sacciolepis interrupta in semi-diy rice. The practice was found to be economically viable also.EnglishThesis