Study On Evaluation Of Growth And Physiological And Biochemical Characteristics Of Superior Clones Of Ash

Six superior clones (R36; R39; R21; R34; H5; H9) of ash which is 5 -year-old and growing in saline habitats were studied, and the native ash(R1)was as CK in this experiment. A randomized block design with four replications, five tree plot and 3m×2m spacing was used.The physiological and biochemical characteristics of those six superior clones were measured and analyzed in order to provide the theory basis for the further genetic improvement of ash.The results of this study were as the following.The branching angle of R21is was the greatest and reached up to 85-95 degrees. It kept 270 days of green and 30 days later for leaf-falling date. The form-factor of R34 was up to 0.51 and the heightest individual of R34 was 7.51m and mean diameter at breast was 10.06cm. It was the fastest growing clones.The branching angle of H5 and H9 were relatively smaller and it,s highest individual was only 2.3m and the mean hight was 7.53m and 7.64m respectively.The mean diameter were 9.01cm and 9.72cm respectively. It was fast-growing and good pole form type.For all the physiological and biochemical indexes measured,the performance of R21 was the best.It has characters with small cell membrane permeability largest biomass produstic,low-MDA; higher protective enzymes activity; high organic osmolyte and strong photosynthesis.The contens of Na + and Cl- of R36 and R39 were lower than that of others.The ratio of Na + / K + were 0.052 (R36), 0.052 (R39), 0.106 (R34), 0.072 (H5), 0.082 (H9), 0.168 (R21), respectively.The are blong to high salt resistant, fast growing and long leaf-green type.Correlation analyze show that membrane permeability is significantly and negatively correlated with POD and SOD , and negatively correlated with CAT, Pro and SP .MDA is negatively correlated with CAT and SP. Pro is significant positively correlated with SOD and POD. RA is significantly correlated with CAT, Pro and SP. Pro and SP, SP with RA, Ca with Cb are significantly correlated. The result of main component analysis, showed that the score of R21 was the highest up to 19.2378.Through the comprehensive analyze R36 and R39 has low-salt ion content, and has a low ratio of Na + / K +. R34 have a good stem form, and faster growth rate than the native ash and increase wood production up to 160%.H5 and H9 has good tree form and faster growth. physiological and biochemical traits of R21 is the most outstanding,in which green period can up to 270 days, the date of leaf-falling was delayed 30-days than the others, and is an ideal landscape tree species.