Screening Technology Of High Quality Branched Apple Nursery Trees

The experiment was studied on two aspects. On the one hand, the apple(Malus domestica Borth.)cultivar Fuji Nagafu No.2 was used to study the effects of Promalin,and a combination of leaf removing and pinching on improving branching of nursery apple trees with T337 and M26 as interstocks and M. robusta Rehd. as rootstock; on the other hand, fertilization with different ratios of nitrogen(N), phosphorus(P), and potassium(K), for growth physiology of the apple(Malus domestica Borth) cultivar Fuji Nagafu No.2 with T337 as interstock and M. robusta Rehd as rootstock was tested using an L9(34)orthogonal design and regression analysis.The results showed that spraying treatments of Promalin and the combination of leaf removing and pinching were effective for improving the apple seedlings branching situation, and the effect was different from the concentrations. With the increase of concentration of Promalin, the the branching numbers were increased; the average branching length, total branching length and branching angles were decreased, however the branching angles in the treatments combining leaf removing with Promalin gained better effect than Promalin spraying alone. Though higher spraying concentration(1 500 to 2 000mg·L-1)of Promalin could produce a number of shoots,which could not meet requirement because of their thin laterals, the few number of effectual laterals and narrow branching angle. According to the experiment results, the treatment combining leaf removing with Promalin at concentration of 750 mg·L-1 is proposed to gain apple trees with well branching situation.In the orthogonal experiment of fertilization the growth and physiological indexes of the nursery apple trees were significantly influenced by fertilization with different proportions of nitrogen(N), phosphorus(P), and potassium(K). Results among the nine combinations, showed that for growth of height,diameter, leaf area,leaf weight,the diomass of different origin(trunk,interstock,rootstock and root)and total diomass, 9.5 g/ strain/year N, 52.5g/ strain P2O5/year, 30 g/ strain/year K2O(N3P1K3)were best.The accumulation of NPK content in leaf, fertilizerition can obviously increase the content of K in leaf, but the accumulation of NP were not obvious changed. The accumulation of nitrogen was not significantly improved in leaf with the high nitrogen treatments.The accumulation of P under high phosphorus level was higher, howere under the lower level of phosphorus the accumulation of P almost no obvious change compared with the control.The content of NPK in leaf of apple nursery trees with N3P1K3 treatment(high N and low PK) was better than the others.In the conclusion that N3P1K3 treatment of fertilization was suitable for the growth of nursery apple trees.