Vol. 6, Issue 12 (2017)

Author(s):
Ajit Kumar Mandal, Ga Dheebakaran, Mahamaya Banik, Arun Kumar and S Arul Prasad

Abstract:
Future climate scenarios indicated that, during the second part of this century Indian agriculture would suffer with elevated temperature and moisture stress. Weeds are one of the important biotic factor, compete the crop for its resources. It is very difficult to eliminate weeds completely from agricultural system. Weeds respond very quickly to stress and adopt easily than crops. In this context an investigation was carried out at Agro Climate Research Centre, Tamil Nadu Agricultural University, Coimbatore during 2015 -16 to understand weeds response to climate change for preparing ourselves to manage them during future climate scenarios. Experiment was carried out as pot culture in climate control chamber under CRD with 10 treatments and three replications. Each treatment was a combination of one temperature and one moisture level. Three temperature levels viz., ambient (0^oC), +2^oC and +4^oC increase over the ambient. Two moisture levels viz., supply of moisture at 100 percent of evaporation (M₁₀₀) and 60 percent of evaporation (M₆₀) occurred previous day. The results inferred that, the problematic weed Cynodon dactylon had high acclimatization capacity and produced more growth under elevated temperature up to +4^oC, with sufficient moisture. The C₄ pathway of Bermuda grass helps that weed to utilise the moisture and temperature more efficiently even during stress and produce more growth. Moisture stress with increased temperature had negative effect on growth, but induced the early flowering and more seed production in Cynodon dactylon. It is concluded that, in future elevated temperature, during the rainy season, the crop production would suffer with Cynodon dactylon menace. Hence, necessary protection measures to be planned during rainy season and precaution measures to be planned during moisture stressed summer to control the weeds before seed setting.