Author(s):

Manisankar G and Ramesh T

Abstract: Climate change refers to a statistically significant variation in either the mean state of the climate or in its variability, persisting for an extended period (typically decades or longer). Under changing climate, high temperature and elevated CO₂ are predicted to increase in frequency, causing serious challenges to sustain global food security. Among the 86-plant species which supply most of the world's food, only five are C₄ species. Among 18 most troublesome weeds in the world, 14 are C₄ species. Most of troublesome weeds species are C₄, while most major crops areC₃photosynthetic pathway. Various studies revealed that both crops and weeds respond to changing climate scenario. Weeds comes under C₃ pathway may dominate under elevated CO₂ conditions, whereas in elevated temperature, C₄ weeds may dominate. The interactive effect of elevated CO₂ and temperature showed that C₄ weeds dominate over C₃ weeds. Crop-weed competition was low at elevated CO₂ whereas high under elevated temperature. The interactive effect of elevated CO₂ and temperature on crop-weed competition was high. Hence, weed management is considered as a major threat to future agriculture.

Pages: 427-431  |  1223 Views  321 Downloads

Download (400KB)