The Effect of Water Deficit on Chlorophyll Fluorescence, Vegetative Characteristics and Grain Yield of Corn Hybrids
Subject Areas : Journal of Plant Ecophysiologyhouman homayouni 1 , victoria khazarian 2 , Mohsen Saeidi 3
1 - Lecturer, Mahestan Higher Education Institute
2 - Professor, Institute of Botanic, National Academy of Sciences of Armenia, Yerevan
3 - Assistant Professor, Department of Agronomy and Plant Breeding, Faculty of Agriculture, Razi University, Kermanshah
Keywords: Leaf area index, Plant height, Quantum yield of photosynthesis, Restriction of humidity,
Abstract :
Restriction of humidity is one of the main factors limiting production in arid and semiarid regions. To evaluate the effects of water deficit on chlorophyll fluorescence, vegetative characteristics and grain yield of corn, an experiment was conducted a spilt plot plan in the form of a completely randomized block design in triplicate in Karaj in 2009 and 2010. The main plots consisted irrigation, including full irrigation (I1), 12.5 % (I2), 25 % (I3), 37.5 % (I4) and 50 % (I5) water deficit, and the subplot consisted corn hybrids including SC704, SC500 and SC301. In terms of fluorescence chlorophyll parameters, in the Leaf10 stage and tasseling stage, there was a meaningful difference among corn hybrids, while in other cases a meaningful difference was not observed. The leaf area index, plant height and grain yield decreased by decreasing the amount of water in water deficit treatments. However, decreasing water to 12.5 % did not have a meaningful effect on the grain yield. The lowest grain yield was related to I5 (with performance of 2497 kg/ha). Among hybrids, SC704 (with yield of 4592 kg/ha) accrued the highest grain yield to itself. At the same time as the intensification of deficit irrigation, the decrease in the level of photosynthesis that occurred through decrease of leaf area played a more important role compared to photosystem II efficiency in grain yield. Moreover, due to the scatted data of the quantum yield of photosystem II achieved, which are affected by the environmental conditions.
