Variation within clones and families and superior individual selection in different cultivars of Camellia oleifera‘Ruanzhi’.

Camellia oleifera ‘Ruanzhi’ is an excellent germplasm with larger variation in seed reproduction, which can be further improved. The project selected the objects as four contrast experimental forests of ten-year-old grafted clones and open-pollinated seedlings of C. oleifera ‘Ruanzhi’ in Sanjiang County, Guangxi Province, analyzed the main variations of economic characters of four different clones and families. The results showed that there are significant differences between different clones fruit heights, fruit diameters, fruit shape index, fresh fruit weight, pericarp thickness, single fruit seed number and seed mass, and the clone repeatability was between 0.14-0.95. Besides, within the same family, there are significant differences among fruit height, fruit diameter, fresh fruit weight, pericarp thickness, seed mass, seed yield, oil percentage in kernel and oil percentage in seed, and the family heritability was between 0.1-0.91. The varied range of single plant within the same clone and family was large, while the upper limit of the varied range in the single plant within the family was obviously higher than that of the clones, which laid the foundation for the superior selection of C. oleifera ‘Ruanzhi’. The study finds that among the 15 seed indexes, 14 indexes’ average value of the family were higher than that of the clones, among which the fruit oil content of the families was 83.64% higher than that of the clones, the mean value of 4 seed indexes (fresh fruit weight, seed mass, dried seed weight and dried kernel weight) was 45% higher, and the mean value of 3 seed oil indexes (oil percentage in fruit, oil percentage in seed and oil percentage in kernel) was 20% higher. Compared with grafting propagation, the seedling breeding plants have obvious advantages in seed weight index and oil content index, although the found needs more surveys to be confirmed, it should be a reminder of thinking about the utilization strategies of excellent germplasm of C. oleifera ‘Ruanzhi’. With principal component analysis of the main economic characters and in accordance with the selection rate of 5%, choosing 6 superior plants with high value of comprehensive assessment from 4 ‘Ruanzhi’ families, the dominance ratios of the mean value of superior plants’ fruit oil content and that of clones and that of families are 4.1 and 2.2, respectively, which can be used as excellent local germplasm to develop and make use of.