The Description Of Different Developmental Stages Of Persimmon And The Classification Of Anthracnose Resistance

Persimmon(Diospyros kaki),as a traditional fruit tree in China,has rich germplasm resources,which can not only be eaten fresh,but also be reprocessed.In recent years,persimmon industry has developed rapidly.In addition to the traditional East Asian region,persimmon is also one of the important fruits for commercial cultivation in the Mediterranean region.Anthracnose as a common fruit tree fungal disease in most crops have occurred,China’s persimmon main production areas most of the cultivated varieties of persimmon anthracnose pathogen resistance level is not high disease outbreak on the development of persimmon industry and fruit farmers economic income will cause serious impact.And the prevention and control of anthracnose can not blindly rely on chemical control,need to combine certain management measures and the breeding of new resistant varieties,from many aspects for the development of persimmon industry to provide protection.In this study,based on BBCH(Biologische Bundesanstalt,Bundessortenamt Chemische Industrie)standard,the different growth stages and states of cultivated persimmons were described accurately and standardized.Secondly,through outdoor anthracnose experiment,the resistance evaluation and identification of 130 main persimmon cultivars were carried out,which provided theoretical basis for screening and identification of persimmon anthracnose resistant germplasm and future resistance breeding research.The study is as follows:1.Using the four representative types of persimmon in the national field genebank for persimmon: ’Taishuu’(monoecious plant),’Luotian Tianshi’(female plant),’Mopanshi’(female plant)and ’Male 8’(Male plant).According to BBCH-scale,the growth phenology of persimmon varieties was systematically coded and described.The main growth stages of persimmon varieties were divided into vegetative phenology and reproductive phenology.The vegetative phenological stages included bud development(0),leaf development(1),shoot development(3),senescence and beginning of the rest period(9).Reproductive phenology includes inflorescence emergence(5),flowering(6),fruit development(7),maturity of fruit(8).Based on the above criteria,the developmental stages of different persimmon varieties were drawn.In the bud development stage(0 stage),the bud development of ’Mopan persimmon’ was earlier.In the flower development stage(5 and 6),’ The flower buds of ’Taishuu’ and ’ Male 8’ expanded and bloomed earlier.In addition,’Male 8’ has the longest flowering period,which is more conducive to artificial or natural hybridization as a male parent.The fruit growth period(7 and 8 stages)of ’ Mopanshi ’ was the shortest,and the fruit coloring time of ’Taishuu’ was earlier than that of ’ Mopanshi ’ and ’ Luotian Tianshi’.2 Persimmon anthracnose isolation and identification,the ’Taishuu’,’Mopanshi’,’Fuping jianshi’ different parts of the disease(branches,leaves,fruits)persimmon anthracnose bacteria separation and purification after obtaining 5 suspected different types of strains,according to the morphological characteristics of persimmon anthracnose pathogenic bacteria,ITS sequence analysis and pathogenicity analysis,Finally,Colletotrichum horii was confirmed as the pathogen of anthracnose in the national field genebank for persimmon.3.On the observation of the characteristics of persimmon anthracnose infection in different parts and the investigation of the incidence of persimmon anthracnose in the national persimmon germplasm resources nursery from 2019 to 2020,the regularity of persimmon anthracnose incidence was summarized: To Japanese persimmon persimmon anthracnose young leaves,mature fruit,and strong infection,and mainly concentrated in late may to October each year,under the condition of high temperature and high humidity its rapid onset and high fatality rate and infection cycle pattern formation,so for persimmon orchard anthracnose prevention and control of the main case is given priority to,complementary with various agronomic measures;A preliminary experiment was carried out on the selection of insecticides for the prevention and control of persimmonic anthracnose.The results showed that fenazolimide,fenazolimide and fenazolimide had good inhibitory effect on the pathogenic bacteria of anthracnose,and could be used as alternative insecticides for the prevention and control of anthracnose in field.4.Persimmon germplasm resources of anthracnose resistance identification and the preliminary development of resistance classification standard,resistance investigation should be in the past on the premise of the number of disease spot statistics on the phenotypic characteristics of the disease materials recorded.Including the initial onset time,the size of the plaque,the severity of the disease,the expansion rate of the plaque and so on.The method of artificial identification of resistance to infection was to choose regional spore suspension drip method instead of spraying method to carry out a more systematic investigation of the incidence under the same environmental conditions.Resistance of 130 varieties of persimmon identification and phenotypic descriptions,select a disease-resistant varieties ‘Yuanqu Ba Yue Hong’,6 high resistance varieties: ‘Tong Pen Shi’,‘Zhaoan Yuan Xiao Shi’,‘Cheng Su Shi’,‘Baoshan Da Fang Shi’,‘Hyakume’,‘Ying Shi’.resistance and sums up the classification standard of experimental method and the appraisal process.