How much leaves near the ear contribute on yield and yield components of maize?

Abstract

In order to study the role of leaf position on yield and yield component of maize, this research was conducted based on randomized complete block design with three replicates at the research field of Urmia University, Urmia, Iran, in 2011. For determine the role of leaf position in maize yield, we used the leaf removing (clipping) treatments. Leaf clipping treatments contain ear leaf clipping, above ear leaf clipping, below ear leaf clipping and control (without leaf clipping) that imposed at one week after ear initiation. Leaf removing had a significant effect on all measured traits (number of seed per row, row number per ear, ear length, 1000 seed weight, seed yield, biological yield), except harvest index. Removing of above leaves decreased 6.68% the number of seeds on ear compare to control. The highest 1000 seed weight (274 g) was observed in plants without leaf clipping. Ear leaf clipping and below ear leaf defoliation ranked second for 1000 seed weight. Whereas plants without any leaf clipping had the utmost seed yield (8.77 t ha-1) but defoliating of leaf above ear lead to lower seed yield (6.77 t ha-1). Leaf removal above ear decreased 22.80% biological yield compared to control. The correlation analysis showed that all traits had positive correlation with seed yield. The most correlation was between ear length and number of row per ear (r=0.89**). Also, number of seed per row (r=0.71**), 1000 seed weight (r=0.67**), ear length (r=0.65**), biological yield and harvest index (r=0.59**) showed the most correlation with seed yield, respectively. Results revealed that the most reduction in all traits accrued in maize plants with above ear leaf clipping, this results indicated that the important roles of leaves position especially the role of above ear leaves in yield and yield components of maize.