Influence of mother tree age and rejuvenation on the physiology and adventitious root occurrence of Castanea henryi scions
[Objective]This study aims to investigate the effects of mother tree age and basal rejuvenation on the semi-lignified softwood cutting rooting of Castanea henryi,and analyze the possible reasons from physiological and anatomical characteristics aspects,providing theoretical and practical guidance for C.henryi propagation by cutting.[Method]Basal rejuvenation treatments were carried out on 2-year-old and 8-year-old C.henryi mother trees,with the new semi-lignified branches as the experimental material,and branches from non-rejuvenated trees as the control.The basal portions of the cuttings were taken at 0 d,7 d,and 14 d after cutting,and the anatomical observed by making paraffin sections.The dynamic changes of soluble sugar content,soluble protein content,lignin content,enzyme activity,and hormone levels were measured,and the rooting rate and number of roots were calculated after cutting 60 days.[Result]1)After cutting 14 days,adventitious roots were observed on the cuttings of 2-year-old C.henryi,while white protrusions appeared at the base of the cuttings of 8-year-old C.henryi.2)The older the mother tree,the lower the rooting rate,and basal rejuvenation had no significant effect on the adventitious root formation of C.henryi cuttings(P＞0.05).The rooting rates(68.0%,70.0%)and the number of adventitious roots per cutting(11.3,10.6)from 2-year-old control and its rejuvenated cuttings were significantly higher than those of 8-year-old control and its rejuvenated cuttings(3.2%,4.4%)and the number of adventitious roots per cutting(3.2,2.9)(P＜0.05).3)The lignin content of 8-year-old cuttings was significantly higher than that of 2-year-old cuttings during the adventitious root formation(P＜0.05),and rejuvenation did not reduce the lignin content of the cuttings.At 7 days,the soluble protein content of 8-year-old cuttings was significantly lower than that of 2-year-old cuttings in both control and rejuvenation treatments(P＜0.05).4)During the adventitious root formation process,the IAAO enzyme activity did not differ significantly among different ages and rejuvenated cuttings(P＞0.05);the IAA level of 8-year-old cuttings was significantly higher than that of 2-year-old cuttings(P＜0.05).At 7 days,the SOD of 2-year-old C.henryi cuttings was significantly higher than that of 8-year-old cuttings(P＜0.05),and the GA3 content of 8-year-old cuttings was significantly higher than that of 2-year-old cuttings(P＜0.05).[Conclusion]Mother tree age is the main factor affecting the adventitious root formation of C.henryi cuttings,and simply basal rejuvenation treatments may not be suitable for increasing the adventitious rooting rate of adult C.henryi cuttings.Regulating the synthesis and metabolism pathways of lignin may be the key to improving the adventitious root formation of adult C.henryi cuttings.
tree agerejuvenationadventitious root occurrenceCastanea henryi
万方数据
维普
