Effect of elevated atmospheric CO₂ concentrations on growth and yield of blackgram (Vigna mungo L. Hepper) - a rainfed pulse crop

Abstract

The response of blackgram (Vigna mungo L. Hepper) to two levels of elevated carbon dioxide (550 and 700 ppm) in terms of growth and yield was investigated and compared with ambient CO 2 level (365 ppm) using open-top chambers. The growth parameters viz., length and weight of root and shoot, root:shoot ratio, leaf area and weight significantly increased at 700 ppm CO 2 when compared with 550 ppm. The percentage increase in total biomass at 700 and 550 ppm CO 2 was 65.4% and 39%, respectively compared to the ambient (chamber) control. The increase in total seed yield at 700 ppm (129%) was due to an increase in number of pods per plant and 100 seed weight, whereas at 550 ppm (88.7%) it was due to an increased number of pods/plant and seeds/pod. The results indicate variable responsive effects at different levels of CO 2 emphasizing the pertinence of research on elevated CO 2 in various agroecological inhabitations all over the world. The indication of higher responses for root and leaf at initial growth stages at the higher elevated level of CO 2 (700 ppm), which leads to better root establishment, achieving early photosynthetic efficiency and also better biomass production, and its improved partitioning can be reckoned as a positive aspect of increasing concentrations of CO 2 in atmosphere. The harvest index increased significantly to 35.7 and 38.4% at 550 and 700 ppm, respectively; it is a very important phenomenon in pulses for breaking the yield barrier.

Impact of elevated Carbon Dioxide on two groundnut genotypes (Arachis hypogaea L.) under Open Top Chamber facility

“…This resulted in decreased HI of K-9 at eCO2 revealing that this genotype was not able to take the advantage of enhanced CO2 environment in terms of yield. The results which are in tune with previously reported findings revealed a significant increase in the HI in black gram due to their improved partitioning efficiency under eCO2 conditionby Vanaja et al [15]. The results obtained from the present study showed an increase in the dry matter production as well as economic yield at eCO2 level.…”

Climate Change: Seed Production and Options for Adaptation

“…In water stress conditions, this may allow plants to retain more seeds, but yields will always be lower compared to those in non-resource stress environments [15]. Sometimes there is also an increase in seed mass [21], although the effects of elevated CO 2 on seed mass are highly variable [22].…”

Global Warming and Its Possible Impact on Agriculture in India

“…The growth and yield response of black gram (Vigna mungo) to CO 2 concentrations (550 and 700 ppm) was investigated and compared with ambient CO 2 concentration (365 ppm) using open-top chambers (Vanaja et al, 2007). The growth parameters (root and shoot length, leaf area, and root volume) were significantly greater at 700 ppm CO 2 than at 550 ppm.…”

“…10 Yield parameters of black gram (of 10 plants) under 365, 550, and 700 ppm CO 2(Vanaja et al, 2007) …”