Study On Germplasm Resources And Elite Germplasm Selection Of Camellia Oleifera In Sanjiang Area

Oil-tea(Camellia oleifera Abel.)is an important economic tree species and plays an important role in the agricultural economy of Sanjiang country in Guangxi province.However,due to extensive local management and low utilization rate of superior cultivars,most oil-tea forests are still in a low-yielding state.It is of great significance to study the variation rule of important characters of regional oil-tea germplasm,and to selete elite germplasms.In this paper,three kinds of oil-tea types widely planted in sanjiang area were studied.The variation pattern of local oil-tea germplasms was effectively understood through the exploration of local germplasms.In addition,individuals with excellent comprehensive traits were selected as low-yield forest reconstruction materials.On this basis,the genetic diversity of local oil tea germplasms was analyzed by SSR markers.The genetic distance between different types of oil tea was compared.An overview of the mating system of local oil tea was illustrated with the case of C.oleifera ’Ruanzhi’.The fingerprint of three types of oil tea was constructed,which has certain reference value for the further conservation and improvement of local oil-tea germplasm resources.The results showed that:(1)Of the three types of oil-tea,C.oleifera of Mengjiang was superior to C.oleifera ’uanzhi’ and Camellia meiocarpa in the growth of the tree body.The C.oleifera ’Ruanzhi’ was superior to the other two types in the fruit oil content,and it was the best in oil producing efficiency.(2)The genetic stability of the growth index of different clones of ’Ruanzhi’ was better than that of the family and more extensive variation within the family line.However,the economic characters of family lines were better than that of the clones in general,and the mean oil content of family fruit was 83.64%higher than that of the clones.(3)According to the comprehensive model evaluation method,in accordance with the rate of 5%,6 seedlings of ’Ruanzhi’,3 seedlings of Mengjiang and 9 seedlings of C.meiocarpa were selected to improve utilization.(4)The genetic diversity analysis of three types of oil-tea shows that:C.oleifera of Mengjiang>C.oleifera ’Ruanzhi’>C.meiocarpa.Genetic analysis showed that compared with C.meiocarpa,the genetic relationship between Mengjiang and ’Ruanzhi’ was closer.(5)Mating system analysis of ’Ruanzhi’ showed that C.oleifera ’Ruanzhi’ was highly heterozygous in the local area,and there is no correlation copulation.(6)Based on SSR molecular markers,the fingerprint map of the selected individuals was constructed,and different types of oil-tea could be distinguished according to the commonness of the fingerprint.This paper proposed about germplasm resources conservation of oil-tea in the region,the strategy and way of improvement and utilization.The enormous differences in the economic traits of "Ruanzhi"sexual and asexual reproduction should be taken seriously.It has certain theoretical and application reference value for the related research and industrial development of oil tea,and has certain guiding significance for the management,improvement and utilization of oil tea germplasm resources in sanjiang area.