Study On The Application Of Semi-Open Cuttage Technology Of Kiwifruit

Kiwifruit belongs to Actinidiaceae,Actinidia,which is a perennial woody plant.Beca use of its rich nutrients,the content of vitamin C ranks first in fruits and is favored by cons umers.Cutting is an important method for asexual propagation of woody plants,which has the advantages of maintaining the excellent characters of mother plants,blooming and fruiti ng earlier,producing uniform plants,more breeding materials,low production cost,easy to master and so on.Therefore,exploring the application of cutting technology in kiwifruit is of great significance to the establishment of kiwifruit rapid propagation system.In the experiment,the suitable cutting substrate was selected by changing the cutting e nvironment.The effects of different growth regulators,substrate ratio,humidity and stem t hickness on the growth of kiwifruit hardwood cuttings and tender wood cuttings and the eff ects of micro-root grafting on the growth of kiwifruit seedlings were studied.The following results are obtained:If the monthly average air temperature,humidity,monthly average wind speed（except August）and monthly average soil temperature of the new seedbed in the greenhouse are hi gher than those outside the greenhouse and the old seedbed in the greenhouse,cutting exper iments are carried out on the new seedbed in the greenhouse.It can effectively control envir onmental factors such as air temperature,humidity and wind speed in the seedbed.It is help ful to further study the effects of suitable substrate,substrate ratio and humidity,growth reg ulators and stem thickness on kiwifruit cutting rooting.The effects of finished substrate and common substrate on the growth of kiwifruit cutti ngs were studied.the results showed that the rooting rate,rooting number,root length,root surface area,root volume,germination rate and leaflet number of finished substrate of’MX-1’and’Hayward’were higher than those of common substrate.The effects of different growth regulators on the growth of softwood cuttings of’Nong da Jinmi’and’Hayward’were studied.The growth regulator was IAA 200mg L^-1.The cuttin gs of’Nongda Jinmi’kiwifruit could obtain higher rooting rate of 38.3%,root length 11.1c m,root surface area 4.68cm²,root volume 0.16cm³and germination rate of 89.0%.Cutting’Hayward’also obtained higher rooting rate of 50.2%and sprouting rate of 90.7%.The effe cts of different substrate ratio and humidity on the growth of softwood cuttings of’Xuxiang’and’Gezao’were further studied.The relative water content of substrate suitable for softw ood cuttings of’Gezao’was 70%.When the matrix ratio is vermiculite:perlite 1:1,higher r ooting rate,root length,root diameter,root surface area,root volume,germination rate and number of leaflets can be obtained.The relative water content of substrate suitable for’Xux iang’kiwifruit softwood cutting is 70%,and the ratio of substrate is vermiculite:perlite at 1:1,the root system is sturdy,and the rooting rate,root length,coarse root surface area and ro ot volume are the highest.The effect of stem thickness on softwood cuttings of’Xuxiang’a nd’big seed’was studied.When the stem thickness of’Xuxiang’was 0.6～0.9cm,the rooting rate was higher,and the rooting rate,root length,root surface area,root volume and germi nation rate were better.When the thickness of stem segment of’big seed’is 0.5～0.7cm,the number of rooting is more and the germination rate is higher.The types of growth regulators,different substrate ratio,humidity and stem thickness were selected for each kiwifruit variety during softwood cutting.in addition,the types of gr owth regulators,different substrate ratio and humidity and stem segment thickness of each kiwifruit variety were selected.Combining the best influencing factors of the above researc h,hardwood and softwood cuttings were carried out on’Xu Xiang’,’Nongda Jinmi’,’Big see d’,’Gezao’and’MX-1’.The rooting rates of hardwood cuttings were 63.5%,36.7%,96.3%,98.8%and 98.2%,respectively.The rooting rates of softwood cuttings were 69.0%,50.0%,97.0%,99.2%and 98.7%,respectively.After microroot grafting cuttings of’Xu Xiang’and’Nongda Jinmi’,the days required f or leaf spreading and rooting were significantly shortened after microroot cutting of’Nongd a Jinmi’and’Xuxiang’.Generally,it only took 20 days,and the interface between the root g rafting and cuttings healed well,and the grafted roots grew new roots,and the plants grew healthily.It takes 30 days for’Xuxiang’.The interface between root grafting and cuttings he als well,and new roots grow out,and the plant grows healthily.Micro-root cuttage overca me the problems such as insufficient supply of nutrients to buds in early cutting,and the ro oting rate of cuttings was further improved.The root system is formed at the base of the cut tings,and the whole kiwifruit cuttings form two sets of roots.The method is simple and eas y to operate,reduces the cost of raising seedlings,ensures the survival rate of cutting seedli ngs,and is suitable for the practice of industrial seedling management and improve econom ic benefits.