EFFECT OF FOLIAR APPLICATION OF K , Fe , Zn , CO2 ENRICHMENT AND LIGHT INTENSITY ON GROWTH OF SOUR ORANGE SEEDLINGS.

Abstract

Influence of different foliar fertilizers, CO2 enrichment and light intensity on growth characteristics of sour orange seedlings grown under nursery conditions from October 2009 to May 2011.Six- month old sour orange seedlings were sprayed 7 times during the study period by using Three foliar fertilizers namely KNO3 , Fe-EDDHA and ZnSO4 in three concentrations: 0 (distilled water was used for spraying the control transplants), 5000 mg K L-1 + 20 mg Fe L-1 +15 mg Zn L-1 and 10000 mg K L-1 + 40 mg Fe L-1 + 30 mg Zn L-1 .The transplants also exposed to three CO2 levels , near those of ambient air( 0.0385 % ) , ( 0.0685 % ) and ( 0.0985 %) .The seedlings also exposed to two light intensities ( 25 % and 50 % ) of sun light . The results demonstrated that the sour orange seedlings sprayed with ( 10000 mg K L-1 + 40 mg Fe L-1 + 30 mg Zn L-1 ) and exposed to ( 0.0985 %) and ( 50 % ) of sun light gave thehighest values for number of leaves, leaves area ,shoots per seedling,stem diameter and shoot carbohydrate percentage