ملخص البحث
Field experiment of this investigation was carried out on date palm (Phoenix dactylifera L.) Zaghloul cultivar growing in Edco district, El-Behera Governorate Egypt during the two successive seasons 2007 and
2008. Two previously studied pollinators were used in this study, named here (A) and (B). The experiment was designed as randomized complete blocks with four replicates (each spathe as one replicate) in addition to the
control (non-pollinated spathes). Results proved that pollinated spathes by pollinator (A) had significantly greater GA content than those pollinated with pollinator (B), while the highest content was found in fruits of 3
non-pollinated spathes control in the first season, however a different trend of results was obtained in the second season. Moreover, there were two district peaks of GA in fruits of pollinated spathes as compared with 3
only one peak of GA increase in fruits of non-pollinated spathes. Spathes pollinated with pollinator (A) 3 showed a higher 1AA content in the fruit as compared with using pollinator (B) in a consistent manner.
However, 1AA content in seedless fruits (without pollination) was not consistent, as compared with fruits of pollinated spathes. Fruits of pollinator (B) had significantly greater ABA than those of pollinator (A) in both
seasons. Meanwhile, fruits of non-pollinated spathes had consistently greater amount of ABA as compared with fruits of pollinated spathes. Changes over time, proved that ABA tended to increase in the fruit after
pollination then declined as the fruit tended to go through the kimri stage of development with a clear pattern especially in the first season. Spathes pollinated with pollinator (A) had significantly greater zeatin content than
those pollinated with pollinator (B) in both seasons. However, non-pollinated spathes did not show a consistent pattern in fruit content of zeatin, as compared with that of pollinated spathes. Furthermore there was
a clear peak of zeatin content in all types of fruits which coincided with the initiation of the enlargement phase in pollinated spathes. The values and trends of kinetin in the fruit varied between the two seasons, since there
was no significant difference in such phytohormones between pollinated and non-pollinated spathes in the first season. In the second season, fruits of spathes pollinated with pollinator (A) had much higher content of
kinetin as compared with those in the spathes pollinated with pollinator (B). The data showed that benzyl adenine content in the fruits of spathes pollinated with pollinator (A) had significantly greater amount than
those of spathes pollinated with pollinator (B). Even non-pollinated spathes contained fruits with much less benzyl adenine than fruits of pollinator (A). With regard to the time factor, the data revealed that benzyl adenine
by the end of Hababouk reached a peak in the fruit. In conclusion, results revealed that some phytohormones might be involved in such metaxenic effects especially GA , IAA, zeatin and benzyl adenine while abscissic acid 3 was greatest in fruits of non-pollinated spathes as compared with fruits of pollinated spathes. These results could be utilized to recommend pollinator (A) for "Zaghloul" date spathes and may reveal the significance of applying such phytohormones (GA , IAA, zeatin and benzyl adenine) at the beginning of cell enlargement 3 phase (or the Kimri stage) to obtain similar enhancement of such fruit characteristics