Effects of macronutrients (N,P,K) ON quantity and quality of piarom Date_palm.

Extraordinary importance of date product especially in Hormozgan province and also it's nondenial effect of macronutrient elements such as Nitrogen, Phosphorus and Potassium on quantity and quality of this product, caused this research to be performed. Undoubtly, Piarom date is the best and the most commercial date variety in the region that has high desirability in global markets. So, this research was done on this date variety . Palmgroves of the province, are aften run without using chemical fertilizers, therefore, yield mean and also quality of date product is lower than the present potential. In order to chose the best fertifizer combination of macroelements in Piarom date variety, the research was accomplished during 2 years on 84 fruitful trees which were 12 years old and almost hemogenous in Haji-Abad agricultural research station.Treatments of this research consisted of four levels of Nitrogen (0,350, 700 and 1050 grams/ tree), there levels of Phosphorous (0, 300 and 600 grams/ tree), plus two extra treatments of Potassium (300 and 600 grams/ tree) with three replications (with two trees in each replication), in a factorial manner and in a randomized complete blocks design. Fruit decreasing was done in a ratio of 8 leaves to 1 cluster. Irrigation was done through drop system and also pollination according to region custom. The production was harvested every year in the early of Aban and the yield was measured. Leaf analysis and fruit quality analysis were done at soil and water laboratory and fruit analysis labaratory of agricultural research and natural resource center of Hormozgan province, respectively. Obtained raw data was analyzed statistically by MSTATC software and means comparison was done by Duncans' multiple range test. The results show that year factor has caused meaningful differences in measured plant responses, except for cluster numbers,Potassium, Fe in leaf and fruit pH. Furthermore, it is seen in statistical analysis of two years, that nitrogen levels have caused statistical variations in all considered parameters. The effect of different Phosphorus levels on all plant responses was meaningful except for cluster numbers, concentration of Nitrogen, Zinc and Copper in leaf. Also, interaction of these two factors has been meaninngful in some cases. Also, About extra treatments of Potassium, year element has had meaningful effect on few parameters and hasn't changed the others. Furthermore, Potassium treatments, statistically caused meaningful variations in some plant responses, meanwhile treatment 14, that is, using 600 grams Potassium ( plus 700 grams Nitrogen and 300 grams Phosphorus ) to each tree, has acted more effective (Except for concentration of Fe in leaf, which is increased in treatment 13, that is, using 300 grams Potassium).