بررسی روند و میزان جذب عناصر غذایی در سه گونه آزمایشگاهی جهت بهینه سازی تولید نهال به روش آزمایشگاهی

An attempt was made to study the effects of different concenterations of N, P and K with Special attention to different forms of N such as NH4+ and NO3-, on micropropagation of Aspen tree (Populus tremula L.). The medium which was employed was ACM but addition and deficit of N, P and K compare to ACM medium was treated. N content in trentments media was also NH 4 + and NO3- in the proportion of 0:1, 1:1 and 1:2. The proportion of N, P and K in the medium was added or less compare to the basic ACM medium. The effects of mentioned factors were Studied on five morphological behaviour concerned to the efficiency of propagation such as: mean of shoots lenght, number of shoots in each microshrub, number of leaves in each microshrub, greenish intensity and size of callus formed in the bottom of each microshrub. The relationship between fresh weight and dry weight of microshrub to absorbtion of N, P and K was also studied. From statistical point of view it was observed that generally 45 day microshrubs were more efficient than 30 day ones. Efficient treatments showed more absorbtion of N, P and K from medium, So only a little of mentioned elements remained in the medium. It was seen that treatments of ACM medium but contain (19 mM k + ) , (6.31 mM k + ), (7mM NH4+ , 7mM NO3-, 1.875 mM H2PO4 -, 19mM k+), (11mM NH4+, 11mM NO3-, 0.625 mM 2 PO 4 - , 6.31 mM NH4 + ) and (11 mM NH4+, 11mM NO3-) showed more advantages (according to morphological behaviours) compare to ACM medium alone. The above mentioned numbers of treatments are 46, 45, 13, 15 and 50 respectively. Key words: Jojoba, Wild cherry, Aspen, micropropagation, Nitrogen sources, phosphorous, potassium, mass production, growth characteristics, coefficient of multiplication.