Preharvest Chitosan Effects on Growth, Yield and Quality of ‘Super Hot’ and ‘Num Khao’ Chili Pepper (<i>Capsicum annuum</i> L.)

Two chili pepper (Capsicum annuum L.) cultivars ‘Super Hot’ and ‘Num Khao’ grown under field conditions in Thailand were sprayed with 0 (distilled water, control), 25, 50, 100, 200 ppm chitosan after one week from transplanting weekly thereafter for five weeks. Chitosan spray improved vegetative growth of both as measured by increased canopy size. It also the plant height cultivar reduced leaf curl incidence cultivar. Leaf size chlorophyll content not significantly affected. Fruit harvested at commercial maturity stage; that is, red-ripe stage light green Khao’. From four harvests intervals, treatment yield because greater fruit production there was a higher number per produced color (L*, a*, b*, sensory color) affected, but overall acceptability response to due quality appearance, glossiness 50 appeared be optimum concentration induce above effects cultivars.