EFFECT OF NITROGEN AND FOLIAR APPLICATION OF PHENOLIC COMPOUNDS ON FLAG LEAF PIGMENTS AND GRAIN YIELD OF SPRING WHEAT (Triticum aestivum L.) GENOTYPES

Abstract

Application of phenolic compounds such as proline, glycinebetaine, silicon, cytokinins, methanol etc. are getting important consideration in modern agricultural research for managing plants to get maximum yield under different environmental conditions. However there is a lack of knowledge about the effects of these phenolic compounds on grain yield, yield components and physiological properties such as leaf photosynthetic pigments. In the context the the present study was conducted during 2015-2016 growing season at the experimental field in the faculty of agriculture, University of Cukurova, Adana, Turkey to evaluated the effects of some phenolic compounds such as proline, glycinebetaine, silicon, cytokinins, methanol etc on chlorophyll (Chl) as well as total carotenoid contents of four bread wheat genotypes (‘Adana-99’, ‘FSD-2008’, ‘Basribey-98’ and ‘Seher-06’) under two nitrogen levels viz., low nitrogen level, LN: 60 kg N ha-1 and high nitrogen level, HN: 180 kg N ha-1 under well-watered condition. The results of the LN showed that the grain yield was only significantly correlated with Chla/b (r=-0.751**) of wheat genotypes. While, under HN, Chla, Chlb, carotenoid and Chla/b were strongly correlated with grain yield (r=0.422*, r=0.635**, r=0.444* and r=-0.590**) respectively. Among the phenolic compounds, proline highly sitimulated the relationships between grain yield and Chlb, carotenoids and Chla/b (r=0.795*, r=0.795* and r=0.811*), respectively. Similary, methanol effects were strongly correlated with grain yield and Chlb and Chla/b (r=0.844** and r=-0.772*), respectively. Therefore it is concluded that foliar application of methanol and proline were significantly increased the flag leaf Chlb concentration which ultimately lead to increase the grain yield of wheat genotypes.