Weeds and Their Response to Changing Climate: A Review

Climate change is one of the most important parameters to cause alteration in weed composition, population growth, life processes, physiological development, and infestation pressure. A few of the weed species may become inactive, while the rest may become aggressive invaders. Weeds possess unique biological characteristics and ecological range that enable them to tolerate and successfully intrude in any ecosystem with varied environmental conditions. Rising carbon dioxide, will benefit C3 crops to expand their photosynthetic capacity, thus leading to increased biomass production and productivity, on the other hand increased temperatures will benefit the C4 crops. These differences in response of C3 and C4 crops to changing climate will influence crop-weed interaction, most likely at the expense of crop. Moisture is another important environmental factor which plays a major role in weed seed germination, thus the survival. Temperature and relative humidity influence the course of absorption, translocation, and metabolism of herbicides in plants, any change in their range leads to decreased herbicide efficacy and thus the weed control. Studies focussed on the performance of weeds under elevated environmental factors help to make strategic decisions on their management before having their impact on change in weed biological aspects, and foresee the future with elevated temperature and carbon dioxide conditions. Weeds such as Parthenium hysterophorus, Sphagneticola trilobata, Prosopis juliflora and Eichhornia crassipes, have been identified as potential future threats. Consequently, exploring the bioprospecting potential of these weeds is seen as an inevitable necessity.