Influence of Zinc Applications on Photosynthesis, Transpiration and Stomatal Conductance in Kharif Rice (Oryza sativa L.) Genotypes

A field experiment in rice investigation was conducted during kharif seasons of 2017 and 2018 at college farm, Navsari Agricultural University, Navsari to study the effect of variety and zinc application on rice.The experiment was laid out in a randomized block design with factorial concept and replicated thrice.The experiment consisted of three varieties viz., IET-25450 (V 1 ), BPT-5204 (V 2 ) and IET-24766 (V 3 ), three soil base zinc application (S 1 ) control (00 kg ZnSO 4 ha -1 ), (S 2 ) 10 kg ZnSO 4 ha -1 at the time of transplanting and (S 3 ) 20 kg ZnSO 4 ha -1 at the time of transplanting and two foliar Zn application (F 1 ) 0 % Zn EDTA and (F 2 ) 1 % Zn EDTA spray at tillering and grain filling stage.Varieties differed significantly in photosynthetic rate, stomatal conductance and transpiration rate.Among the varieties, IET-24766 gave significantly highest photosynthetic rate (44.78µMm -2 s -1 ), stomatal conductance (0.35mMm -2 s -1 ) and transpiration rate (5.66mMm -2 s -1 ) followed by IET-25450and BPT-5204 and soil base zinc application of 20 kg ZnSO 4 ha -1 at the time of transplanting as well as foliar zinc application of 1 % Zn EDTA spray at tillering and grain filling stage resulted in highest values in photosynthetic rate (43.52 and 43.02 µMm -2 s -1 , respectively), stomatal conductance (0.35 and 0.34 mMm -2 s -1 , respectively), transpiration rate (5.38 and 5.17 mMm -2 s -1 , respectively) during in pooled analysis.