الملخص الإنجليزي
Thirty date palms from each of Khalas and Khassab cultivars at 6-7 years of age were selected randomly in Al-Fairooz Farm in Khabourah in Batina. Experiment treatments were applied in factorial design included: organic peat alone with 1000g urea divided into 5 and 4 doses mixed with 500g triple superphophate and 800g K2SO4 and with or without micronutrients. The control included no organic or chemical fertilizer. Mineral fertilizer tended to increase Khassab strand weight and decrease fruits number. The highest number and yield associated with smallest length and diameter were produced by NPK + micronutrients and organic peat. Whereas, in Khalas no significant differences were observed in fruit number, weight and measurments, but NPK 5 or 4 nitrogen doses with micronutrients and organic peat produced the highest yield. Four nitrogen doses with phosphate and K2SO4 resulted in an increase of Khalas yield by 22% over the control and 24.7% over organic peat. The same treatment increased Khassab yield by 77.5% over the control and 130% over organic peat. The five nitrogen doses increased the yield of Khalas by 17.8% over the control and 20.4 % over organic peat. On Khassab it increased the yield by 63% over the control and 112.4% over peat. Five nitrogen doses in Khalas produced higher weight of strand, number of fruits per strand, weight and length of fruit and yield than 4 doses. Whereas, it produced lower strand weight, fruit length and diameter, and higher yield and number of fruits per strand than the 4 doses on Khassab. In both cultivars fruits/strand, number, fruit weight and diameter decreased from Bisir to Rutab, but in contrast to Khalas, yield in Rutab was higher than Bisir. In year 2004 both cultivars produced higher yield, fruit number and weight/strand but lower fruit weight than in 2002 and 2003. Five nitrogen doses increased tannins, pectins, and pH over 4-N doses, but reduced TA% in both cultivars. There were no significant differences in the effect of fertilizers on the pectin, glucose and fructose content of fruit. Pectin content increased when the peat and mineral fertilizers were applied together. An increase in acidity was associated with a decrease in tannin and vice versa. There was a gradual increase in fructose when 5nitrogen doses were added with K and P and organic peat, but not with 4- nitrogen doses, an indication of sweeter dates. Chemical fertilizers resulted in gradual increase in the dry matter percentage. It was the highest with 4- doses of urea + K + P and lower with the control and organic peat and 5 - doses of urea. In both cultivars tannin and moisture decreased with mineral fertilizer. In contrast, TA, dry matter increased, whereas, pectin and sugars followed different trend. Pectins, tannins and TA were lower in Rutab than Bisir. In 2004 pectins and tannins were lower than 2002 and 2003, but TA reduced in Khalas and increased in Khassab with time. No significant difference on Khalas fruit content of N, P, K, Na, Ca, Mg, Fe, Zn, Cu, and Mn. Khassab fruit Mg, Ca, Fe, and Zn significantly increased by application of organic peat over the other fertilizer treatments.
