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The Positive Growth Responses of Winter Cherry to Atmospheric CO2 Enrichment

Paper Reviewed
Sharma, R., Singh, H., Kaushik, M., Nautiyal, R. and Singh, O. 2018. Adaptive physiological response, carbon partitioning, and biomass production of Withania somnifera (L.) Dunal grown under elevated CO2 regimes. 3 Biotech 8: 267.

Winter cherry (Withania somnifera) is a perennial shrub that has been grown and utilized anciently in traditional medicinal practices, particularly in India and Africa (Patwardhan et al., 1998; Singh et al., 2015). And according to Sharma et al. (2018), there is an increasing demand for this species in the international market, leading to a growing interest in improving its cultivation and management to enhance growth. However, to date, little is known with respect to how this shrub might respond to rising concentrations of atmospheric carbon dioxide. Therefore, Sharma et al. set out to learn more on this subject.

The setting for their investigation was the open-top chamber facility of the Ecology, Climate Change and Forest Influence Division of the Forest Research Institute in Dehradun, Uttarakhand, India. There, over the course of one full growth cycle, the team of Indian researchers grew winter cherry under ambient (~400 ppm) and two elevated (600 and 800 ppm) atmospheric CO2 concentrations. Across the length of the experiment, uniform soil moisture was maintained through regular watering and weeding.

Results indicated that elevated CO2 positively influenced several growth parameters of the shrub. As shown in the figure below, for example, photosynthesis increased by 38.6 and 86.7% and net primary productivity rose by 36.2 and 70.5% in the 600 and 800 ppm CO2 treatments, respectively (compared to values measured in the ambient treatment). Similarly, leaf, stem and root biomass experienced CO2-induced enhancements, rising by 53.2, 32.6 and 8.8% in the 600 ppm treatment and by 90.7, 93.0 and 14.5% in the 800 ppm treatment, leading to a total plant biomass improvement of 31.6 and 71.5% in the 600 and 800 ppm CO2 treatments, respectively. Additionally, both instantaneous and intrinsic plant water use efficiency were enhanced in the elevated CO2 treatments (instantaneous by 15-36% and intrinsic by 21-29% in the 600 and 800 ppm treatments, respectively).

In light of the several findings reported above, it is clear that the growth of winter cherry plants will be significantly benefitted by the ongoing rise in the air's CO2 content.

Figure 1. Photosynthetic (a), net primary productivity (b) and biomass production (c) responses of winter cherry (Withania somnifera) under ambient (~400 ppm) and elevated (600 and 800 ppm) levels of atmospheric CO2. Source: Sharma et al. (2018).

Patwardhan, B., Panse, G.T. and Kulkarni, P.H. 1998. Ashwagandha a review. Journal of the National Integrated Medical Association 30: 7-11.

Singh, P., Guleri, R., Singh, V., Kaur, G., Katari, H., Singh, B., Kaura, G., Kaul, S.C., Wadhwa, R. and Pati, P.K. 2015. Biotechnological interventions in Withania somnifera (L.) Dunal. Biotechnology and Genetic Engineering Reviews 19: 1-20.

Posted 23 July 2018