A Comparative Study on Fertilization of Washington Navel Orange Trees

Abstract

The effects of different soil application levels of Natural Elements Compound( NEC) either alone or in combination with EM soil application rates on Washington navel orange trees budded on sour orange rootstock grown under ''KarKashnda'' region, Qalyubeia Governorate condition to study their effects on some fruiting parameters and physical and chemical of fruit characteristics during the two successive seasons of 2013 and 2014. The obtained results revealed that all investigated treatments under study resulted in significantly increased in the most fruiting parameters and fruit characteristics as compared to the control treatment during the first and second seasons of experimental study. Moreover, data indicated that all studied treatments exhibited significantly increased fruit set % , yields either tree yield in kgs or yield expressed as tons per feddan. Furthermore, results displayed clearly that both studied fruit physical properties ( fruit weight, volume, height and diameter ) and fruit chemical characters such as TSS %, total acidity %, total sugers % and fruit juice vitamin C. contents were improved by subjected trees to different investigated treatments as compared with the control in the two experimental seasons of study. Generally, it could be concluded that , all investigated treatments under the study (NEC and EM ) either alone or in combination with them resulted in a significant and positive effects for increasing all fruiting parameters and improving most studied fruit quality. However, the treatment of (NEC 4 x EM 2 ) i.e. (6.0 kgs of NEC x 900 ml 3 /l of EM /tree /year) exhibited statistically the best and the most effect for increasing and improving all investigated fruiting parameters and fruit characteristics of Washington navel orange trees.