| The experiment was conducted in 2006-2009, rely on the rich germplasm collected and conserved in National Field Genebank for Loquat in Fuzhou. Taking the regeneration of resources in the whole field as an opportunity to carry out the identification of loquat seedling growth characteristics, tree growth characteristics, vegetative period, the high yield, inflorescence diversity and fruit characters under the uniform stock, uniform location, uniform planting, and uniform management conditions. Using of the cluster analysis in mathematical statistics and principal component analysis on the classification of ordinary loquat germplasm resources in order to provide the basis for the loquat germplasm collection, preservation, identification, evaluation and utilization genetic resources.The results were summarized as bellow:1. Survival rate, seedling rate, growth volume of graftwood, branch numbers of the loquat germplasm were obvious difference, and the variation coefficients were from 15.1% to 28.5%. From seedling to 30 months after planting, tree hihgt, crown diameter, trunk circumference, thick leaf power, number of central shoots, number of total shoots and number of lateral shoots were obvious difference, and the variation coefficients were from 12.5% to 42.9%. From seedling to 42 months after planting, central shoots heading rate, total shoots heading rate, number of lateral shoots heading rate, number of central shoots heading, number of total shoots heading, number of lateral shoots heading were obvious difference, and the variation coefficients were from 9.8% to 52.7%. There was very significant positive correlation between 8 traits (plant height, plant diameter, branch series, trunk circumference, thick leaf power, central fruit shoots number, lateral fruit shoots number, total shoots number). Tree vigor was highly correlated to plant diameter, lateral fruit shoots number and total shoots number.9 special germplasm with dwarfing were selected.2. The results showed that nutrition of loquat germplasm resources was between 6 months to 42 months. In 42 months after planting, the loquat germplasm resources were at a rapid growth stage, with the plant increment was highly correlated to the plant growing. Rate of center shoot heading, rate of lateral shoot heading and rate of shoot heading were increased with the plant growing. Central shoots number, lateral shoots number and shoots number were highly correlated to center shoot heading number and lateral shoot heading number, and the relationship was strengthening with the plants growing.Based on years of survey results, nutrition evaluation criteria was proprosed:very short (flowering in seeding or planting 12 months, rate of plants heading more than 80%, rate of shoot heading more than 50%), short (flowering in seeding or planting 12 months), medium (flowering in planting 18 months), long (flowering in planting 30 months), very long (flowering in planting 42 months), and 6 special germplasm with very short nutrition were selected.3. The result showed that, loquat yield/plant was abundant in germplasm resource, from 0.4 to 29.1kg. And the variation coefficient was up to 58.8%. There had been significant positive correlation between the field/plant and 13 characteristics, for number of central shoots, number of lateral shoots, number of shoots, number of center shoot heading, number of lateral shoot heading, number of shoot heading, plant height, crown diameter, trunk circumference, ratio of central shoot heading, thick leaf power, fruit weight, number of fruits. The PCA resulted in first main components that represented number of shoots, number of central shoots, number of lateral shoots, number of center shoot heading, number of shoot heading, number of lateral shoot heading, and treie accumulative contribution ratio amounted to 29.04%. The 228 loquat germplasm resources could be divided into 5 classes by high yield metricvalue (D value). Then 10 loquat genotype was selected with high yield (yield/plant>16.0 kg) and productivity (D>0.580).4. Diversity of eight flower cluster characters (attitude of lateral in relation to peduncle, density and number of lateral peduncles, shape, length, width of flower cluster, petal color and corolla diameter) of 210 loquat germplasm resources(Eriobotrya japonica (Thunb.) Lind1., Eriobotryaprinoides Rehd.& Wils., Eriobotrya dayaoshanensis Chen. and Eriobotrya bengalensis (Roxb.) Hook. f.) were studied and analyzed under the same planting conditions.The results showed:(1) there was abundant diversity among them. (2) Diversity index of loquat germplasm resources from different sources varied greatly with the highest was 2.108 (from Yunnan), the lowest was 1.137 (from America). (3) Variance analysis showed that flower cluster length of loquat germplasm from Yunnan and Guizhou were significantly longer than others, flower cluster width of loquat germplasm from Yunnan and Guizhou were very significantly wider than others, both length and width of flower cluster of wild loquat germplasm were very significantly bigger than those of cultivated species and wild relatives.5. Q cluster analysis showed that 199 loquat germplasm resources were seperated into cultivar and wild germplasm when L=87.31; five groups were seperated when L=34.92; the germplasm resources in the same group were most came from the same origin region showing the nearest genetic relationship. R cluster analysis showed that the various characters were decided in 3 groups. Some characters had strong correlativity within a group. Principal component analysis suggested that,86 characters can be simplified to 28 main factors, the cumulative contribution rate of which reaches to 74.7%and according to factor load capacity,58 characters which had more influence were chosed. |
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