Rising Atmospheric Carbon Dioxide and Crop Responses

Abstract

Exponential rise in the atmospheric carbon dioxide (CO2) concentration anthropogenically has aroused interest to characterize the possible response of crop plants to the elevated carbon dioxide in future. Open Top Chamber (OTC) and Free Air Carbon Dioxide (CO2) Enrichment (FACE) technologies were developed to study the crop responses. Study revealed that elevated CO2 significantly ameliorated the adverse stress effect in Brassica species. It also demonstrated the possibility of transferring the CO2 response character in Brassica oxycamp hybrid. The stress induced adverse effect on grain composition of Brassica juncea, particularly on carbohydrate and oil content was significantly ameliorated due to sequestering of carbon and improvement in water status. Studies on rice cultivars showed that additional carbohydrate contributed to the production of mass tillers. The CO2 induced increase in the rice grain yield was attributed to the number of tillers and grain per plant. Additional carbohydrate has helped in balancing the profile of photosynthetic proteins to sustain greater photosynthetic activity in rice plant. These studies lead to the establishment of South Asian CO2 Crop Research Network of Bangladesh, India, Nepal, Pakistan and Sri Lanka and the first Asian FACE facility at the Indian Agricultural Research Institute, New Delhi, India.