Temperature Dependence of Photosynthesis of Bean Plants as Affected by Decenylsuccinic Acid

Photosynthesis of most plants decreases rapidlv when the leaf temperature drops below 100. In contrast, however, several frost resistant plant species still perform appreciable photosynthesis at temperatures below 50 (8). Vetuhova (14, 15) demonstrated that photosynithesis at low temperature was related to winter hardiness. When leaves were cooled, she observed a smaller depression of photosynthesis in winter hardy wheat varieties than in less hardy varieties. Since a solution of decenylsuccinic acid applied to the roots induces considerable frost resistance in young bean plants (7), I determined whether this compound could change the temperature dependence of photosynthesis and report the results here.