Vol. 6, Issue 11 (2017)

Author(s):
Ajit Kumar Mandal, Ga Dheebakaran, Mahamaya Banik, Arun Kumar and Vimal Kumar

Abstract:
Climate change, such as long drought periods and occasional very wet years may worsen weed invasion. Horse purslane has high reproduction and efficient seed dispersal mechanisms which helps them to take advantage of the expected calamities like cyclones and floods. Weeds have more adaptability to stress conditions than crops. Hence, it’s important to understand the thriving capacity of weeds under future projected climate for preparing ourselves to manage during future climate condition. 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 in order to manage them during future climate scenarios. Experiment was carried out under pot culture mode in Climate Control Chamber under CRD with 10 treatments. Each treatment was a combination of one temperature and one moisture level. Three temperature levels viz., ambient (0 ⁰C), +2 ⁰C and +4 ⁰C increase over the ambient and two moisture levels viz., supply of moisture at 100% and 60% ET of previous day. The results revealed that, the problematic weed Trianthema portulacastrum had high acclimatization capacity and produced more growth under elevated temperature up to +4 ⁰C, under sufficient moisture. The C₄ pathway of Horse purslane helped the weed to utilise the moisture and temperature more efficiently even during stress and produced higher growth. Moisture stress with increased temperature had negative effect on growth, but induced early flowering and more seed production in Trianthema portulacastrum. It is concluded from the study that, in future under elevated temperature the crop production would suffer with Trianthema portulacastrum menace under rainy and drought season.Hence, necessary precaution measures against Trianthema portulacastrum have to be included in climate change adaptation technologies.