Location: Adaptive Cropping Systems LaboratoryTitle: Effect of temperature under different evaporative demand conditions on maize leaf expansion
|MURA, JYOSTNA - Oak Ridge Institute For Science And Education (ORISE)|
Submitted to: Environmental and Experimental Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/27/2018
Publication Date: 7/31/2018
Citation: Mura, J.D., Reddy, V. 2018. Effect of temperature under different evaporative demand conditions on maize leaf expansion. Environmental and Experimental Botany. 155:509-5017.
Interpretive Summary: Leaf size is a major determinant of plant photosynthesis and performance that contributes to growth and yield in crops. It depends on environmental variables such as temperature, water availability and light. We studied the effect of different temperatures under dry and wet air conditions on leaf development and plant growth in maize. This research demonstrated that the effect of temperature varies with the surrounding air conditions, with the beneficial effect of high temperature with humid air conditions. High temperatures coupled with dry air had reduced leaf size and plant growth. This study is useful to understand the plant responsive mechanisms to different temperatures under different environments which is helpful in the development of the maize hybrids. These results can also be incorporated into crop models to predict the leaf growth and yield in environments with different temperatures and humid conditions.
Technical Abstract: Leaf expansion and development depends on various environmental variables. The interactive effect of temperature and evaporative demand on leaf development of maize under well-irrigated conditions was studied in detail. The effects of three temperatures (21, 27 and 320C) under high and low evaporative demand conditions were tested in growth chambers. Leaf expansion rate (LER) was increased along with an increase in the temperature under low evaporative demand environments. Under high evaporative demand, the LER increased with temperature until 270C. The depressing effects of vapor pressure deficit (VPD), at 320C with an increase in evaporative demand on LER and other related parameters such as net assimilation rate, relative growth rate, stomatal conductance, transpiration, and photosynthesis were observed. However, the variation in the rate of leaf appearance rate (LAR) appears to be linked to temperature but not VPD. The development of stomata and epidermal cells were clearly affected by VPD with larger and less frequent stomatal cell in low VPD environments. In addition, the relative transcripts of three expansin genes and xyloglucan endo transglycosylase/hydrolases involved in the leaf development were differentially expressed in all the treatments. A significant effect of temperature on the expression of vacuolar H+ pyro phosphatase and VPD on the expression of teosinte branched gene was detected.