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

Abstract

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 the highest values for number of leaves, leaves area ,shoots per seedling,stem diameter and shoot carbohydrate percentage.