The effect of picking dates on fruit set, dropping and nutrient change of Washington navel orange were studied during 2009/2010 and 2010/2011 seasons.It is an evident decrease in N, P and K contents in leaves and juice was obtained with delayed harvest date.Activity of pectin methyl esterase and polygalacturonase (PGU) enzymes in fruit peduncles was increased by delayed picking dates.This was rela...