Studies On The Charactaristic Of The Walnut Tissue Regeneration

Walnut (Juglansregia L.) is one of the important nuts and woody oil species which belongsto the genus Juglans L, family Juglandaceae. walnuts are of important nutritional value,medicinal value and ecological value. Walnuts, as one of the important economic trees which aremore resistant to cold and can tolerate drought, are planted widely in china. The labouring peoplebring a wealth of walnuts growing management experience, but due to walnut’s own biologycharacters, seeding propagation can hardly maintain its desirable traits.How to get the efficientmethods of vegetative propagation is the key to push the walnut industrial development. The trialadopts soft cutting, grafting and pruning means to research the ability that Juglans. regia tissueregenerating and to find out the affecting factors.To discuss in which case the ability that Juglans.regia tissue regenerating is the best. In order to provide theory basis for getting the efficientmethods of vegetative propagation of walnuts. To push the walnut industrial development acrossthe bottleneck and to get more economic and ecological benefits. The main results are asfollowing:1The bud that closes to the cutting parts has the highest shoot sprouting percentage.Compared with the control group, the level of1/5clip weakens the regeneration of the shoot andthe level of2/5、3/5、4/5clip stimulate the shoot regeneration of the walnuts. Among them, theleave of3/5clip has the most impact. Compared with the control group, the chlorophyll contentof each treatment group was improved. But it did not change the dynamic change trend of thechlorophyll content. Each level of different clip all increased the walnut leaf weight. Comparedwith the control group, the leaf weight of the1/5level clip has increased14.2%, withoutsignificant difference. the leaf weight of2/5、3/5、4/5level clip has increased42.6%、36.2%、41.1%，with significant difference. As can be seen from the effects of different clip on leaf area0f the walnut, the control group and the2/5、4/5level clip has no significant difference.2Results of the trial indicated that the cuttings of3-5cm length is the best and2-3cm is themost appropriate cutting depth which can maintain good ventilation and reduce the cuttingsmildew and roting. The cuttings reaching half lignification and the smooth edge can improve thewound being quickly healed; The survival effect in early July was best. The healing rate was 87.5%.3Results of the trial indicated that IBA treatment was better than2,4-D treatment.Indifferent IBA treatments：0、300、600、900、1200、1500、1800、2100mg.kg-1，IBA900-1200mg/kg was the most optimal concentration and can form more callus blocks,What’smore, IBA900、1500mg/kg can induce to grow roots. Different concentration of IBA treatmentshave a significant impact on endogenous plant hormones levels in hardwood.4The bud grafting on the smooth planar had the lower survival rate. Among the three timesgrafting test, the bud transplanting experiment on May29thhad the highest survival rate. Thesurvival percentage of grafting of the3.5cm×3.5cm bud is higher than the2cm×2cm bud. Thebud grafting on the smooth planar has the higher height growth and girth growth.But it has thelower fresh weight.The earlier grafting time,the higher height growth, girth growth and freshweight. The3.5cm×3.5cm bud had the higher basal diameter increasing and seedlings heightthan the2cm×2cm bud..2cm×2cm bud’s fresh weight of under ground portion was lower thanthe3.5cm×3.5cm bud and without significant difference. Under natural conditions,the Ci,Pn andGs of the bud grafting on the smooth planar was lower. The Pn and Gs of the2cm×2cm budwere higher than the3.5cm×3.5cm bud.