Judicious Defoliation Increases the Yield of Tomato by Controlling the Morphological Characteristics

Abstract

Growers usually practice pruning at vegetative and reproductive stages of staked tomato. This study was conducted during November to March for two successive years of 2016 and 2017 to investigate the effect of defoliations on morphological characters, and yield of tomato. Five levels of defoliation comprising of 0 (control), 3, 6, 9 and 12 leaves from basal 17 leaves were applied at beginning of flowering phase considering two widely cultivated varieties of TM-110 and TM-135. The study was laid out in two factors split-plot design with three replicates where varieties as main plot and defoliation levels as sub-plot. Morphological traits like plant height and leaves per plant were not affected up to 6 leaves defoliation irrespective of genotypes and seasons. Fruit yield (Kg) per plant also not affected up to 6 leaves defoliation, rather increases 10.24% and 2.92% for TM-110 and 11.35% and 5.16% for TM-135 in season 2016 and 2017, respectively. However, in season 2017, TM-110 increases 5.00% yield at 3 leaf defoliation. Heavy defoliation (> 6 leaves) causes reduced plant height and smaller number of leaves per plant for all the cases. Fruit yield per plant also decreased as total sink (flower and fruits) production is hampered due to reduction of source sizes. That’s why lowest fruit yield was recorded in 12 leaves defoliated plants. These results indicate that tomato plants can tolerate one-third leaf loss during reproductive stage. Implication of the results in relation to early blight disease management is also crucial.