Effects of short-term temperature fluctuations on leaf photosynthesis in corn (Zea mays)

Publisher Website
Google Scholar
Abstract
The effects of short-term temperature fluctuations on net photosynthetic rates (Pn) are described for a single-cross corn (Zea mays L.) hybrid (Harrow 691). The hybrid was grown at 25.degree. C and subjected to 4 days at either 15 or 35.degree. C, and then administered at 25.degree. C. Genotypic differences in tolerance of Pn to low temperature were studied using 12 hybrids of different maturities grown at 25.degree. C and subjected to 4 days at 15.degree. C. Following low temperature treatment, Pn was initially reduced by about 15% for leaves 5, 9 and 13 of hybrid Harrow 691, but completely recovered after 1 day at 25.degree. C. Following high temperature treatment, leaves 5 and 9 showed similar reductions in Pn, whereas leaf 13 was not affected. The photosynthetic activity of the heat-stressed leaf 9 recovered after 1 day, but that of leaf 5 showed no recovery for 14 days at 25.degree. C. Among 12 hybrids, Pn of the newly matured leaf 7 was reduced after the low temperature treatment, but the reduction was more drastic for 2 late hybrids than for 3 early hybrids. Most hybrids showed complete recovery of Pn after 1 day at 25.degree. C, but genotypic differences were evident. The results reported indicate that further evaluation of the amount of genetic variation in temperature stability in corn could be carried out usefully.

This publication has 0 references indexed in Scilit: