EFFECTS OF POLLEN SOURCE AND MIXING OF POLLEN GRAINS ON PHYSICAL AND BIOCHEMICAL CHARACTERISTICS OF FRUITS IN TISSUE CULTURE-DERIVED DATE PALM (PHOENIX DACTYLIFERA L. CV.  BARHEE')

Occurrence of abnormalities in vegetative growth and fruit set are the most serious problems associated with tissue culture-derived date palm trees. In order to evaluate the pollen source and mixing ratio on fruit characteristics of cv ‘Barhee’, an experiment was carried out in a commercial orchard in ‘Minab’ (‘Homozgan’ province, Iran), during 2008. The treatments were three pollen sources (genotypes 1002, 1003 and 1006) and four pollen mixing ratios (100%, 75%+25%, 50%+50% and 25%+25%+50%). A factorial experiment was arranged as a completely randomized design with four replications (one tree in each replication). Results showed that significant variations were in fruit characteristics among the various treatments. The effects of mixing of pollens were significant on pH, titratable acidity, reducing sugars, weight and length of fruit and pit diameter. Also, the effect of pollen source was significant on pulp weight, total soluble solid and total reducing sugars. Pollen sources and/or mixing of pollens had no a significant effects on moisture, dry matter, fruit diameter, pit length and pulp/pit weight ratio. Results showed that mixing of pollens affected some fruit and pit characteristics of tissue culture-derived date palm and mixing of different pollens could be considered as a new method of pollination for date palm tress.