The Effects of Elevated Atmospheric Carbon Dioxide and Water Stress on Ligth Interception, Dry Matter Production and Yield in Stands of Groundnut (Arachis hypogaeaL.

作者：Steven C. Clifford, Ian Stronach, Arif Mohamed, S.N. Azam-Ali, N.M.J. Crout · 发表于：Journal of Experimental Botany · 年份：1993 · DOI：10.1093/jxb/44.12.1763 · 被引用次数：74 · 研究领域：Plant responses to elevated CO2、Atmospheric chemistry and aerosols、Climate variability and models

Stands of groundnut (Arachis hypogaea L.), a C3 legume, were grown in controlled-environment glasshouses at 28 °C (±5°C) under two levels of atmospheric CO2 (350 ppmv or 700 ppmv) and two levels of soil moisture (irrigated weekly or no water from 35 d after sowing). Elevated CO2 increased the maximum rate of net photosynthesis by up to 40%, with an increase in conversion coefficient for intercepted radiation of 30% (from 1–66 to 2–16 g MJ−1) in well-irrigated conditions, and 94% (from 0–64 to 1·24 g MJ−1) on a drying soil profile. In plants well supplied with water, elevated CO2 increased dry matter accumulation by 16% (from 13·79 to 16·03 t −1 ) and pod yield by 25% (from 2·7 to 3·4t ha−1). However, the harvest index (total poddry weight/above-ground dry weight) was unaffected by CO2 treatment. The beneficial effects of elevated CO2 were enhanced under severe water stress, dry matter production increased by 112% (from 4·13 to 8·87 t ha−1) and a pod yield of 1·34t ha−1 was obtained in elevated CO2, whereas comparable plotsat 350 ppmv CO2 only yielded 0·22 t ha-1. There was a corresponding decrease in harvest index from 0·15 to 0·05. Following the withholding of irrigation, plants growing on a stored soil water profile in elevated CO2 could maintain significantly less negative leaf water potentials (P<0·01) for the remainder of the season than comparable plants grown in ambient CO2, allowing prolonged plant activity during drought. In plants which were well supplied with water...