Study On The Walnut Growth And Fruiting Traits Genetic Analysis Of Hybrid Offsprings And The Superior Trees Selection Of ‘Lvling’

In order to reveal the walnut growth and fruiting traits genetic rules of hybird offsprings of ‘Lvling’, 4 hybrid populations, 374 strains, which were ‘Lvling’בLiaoning NO.1’,‘Liaoning NO.1’בLvling’, ‘Lvling’בLvzao’,‘Lvzao’×’ ‘Lvling’ were used as materials to study the genetic laws of the tree, leaf traits, phenological phase and disease resistance in Lincheng County, walnut breeding nursery of Hebei Lvling Fruit Limited Company, and the superior trees were selected by using the principal component analysis method. The results showed that:1. The variation coefficients of the kinds of fruit branch number, the disease resistance indexes, all phenophases and the internodal length of each hybrid offsprings of ‘Lvling’ walnut were 88.9~101.4%, 58.9%~70.9%, 38.5%~70.9%, 47.2%~50.0%, all of them were above 35%, the highest was 101%, their genetic stabilities were low, they had a high genetic diversities. The variation coefficients of the tree height, trunk girth, crown breadth and leaf traits were 15.4%~19.8%, 23.0%~27.7%, 24.6%~29.9% and 6.6%~28.4%, all of them were less than 30%, the lowest was 6.6%, and their genetic stabilities were relatively high.2.The broad-sense heritabilities of disease resistance index, leaf length, leaf width, leaf area, leaf index and specific leaf weight were respectively 36%~50%, 50.4%~84.6%, 79.2%~97.1%, 35.4%~40.3%, 83.2%~94.5%, 67.2%~79.1%, that the highest was leaf width and leaf index, and the genetic variance was bigger than that of environmental variance, they were not easily affected by environment. The lowest were disease resistance index and leaf area, and they were easily affected by environment, so the selection should be conducted at high generation.3. Among the tree traits, crown breadth, internodal length, the number of long bearing and short bearing branch rate in the hybrid combinations had no significant differences; the tree height of ‘Lvling’ב Liaoning NO.1’ was 4.37 m, which was significantly lower than those of the other three combinations; the trunk girth of ‘Liaoning NO.1’ בLvling’ was the bigest, which was 30.96 cm, it was significantly higher than that of ‘Lvling’ב Liaoning NO.1’, which was 28.00 cm; the number of medium bearing branch of ‘Lvling’בLvzao’ was the highest, which was 16.14 cm, and it was significantly higher than those of ‘Liaoning NO.1’בLvling’ and ‘Lvling’ב Liaoning NO.1’. The differences of the other traits were not significant among the other combinations.4. In the phenophases, the expectations of each female flower phenophase were all above 6, and the expectations of each male flower phenophase were all below 6; the early female flower stage of ‘Lvzao’בLvling’ was the latest whose expectation was 8.11, and significantly higher than that of the other combinations. The end of female flower stage of ‘Lvzao’בLvling’ was the latest whose expectation was 10.84, and significantly higher than that of the other combinations; that the earliest was ‘Lvling’ב Liaoning NO.1’ whose expectation was 6.24; the fruit set period of ‘Lvling’ בLvzao’ and ‘Lvzao’בLvling’ were the latest, whose expectations were respectively 9.92 and 9.07, and there were no significant difference between the two combinations; that the earliest was ‘Liaoning NO.1’ בLvling’, whose expectation was 7.76. There were no significant differences in the phenophases among the other combinations.5. In the leaf traits, the leaf lengths of ‘Lvling’בLiaoning NO.1’ and ‘Liaoning NO.1’ בLvling’ were 12.52 cm and 12.86 cm, the leaf lengths of ‘Lvling’ × ‘Lvzao’ and ‘Lvzao’ × ‘Lvling’ were 12.63 cm and 12.58 cm respectively, and there were no significant differences among those of the two obverse and inverse cross offsprings. The leaf width of ‘Lvling’ב Liaoning NO.1’ and ‘ Liaoning NO.1’ בLvling’ were 6.72 cm and 6.71 cm respectively, those of ‘Lvling’ × ‘Lvzao’ and ‘Lvzao’ × ‘Lvling’ were 6.73 cm and 6.80 cm, there were no significant difference among them too. The leaf area and specific leaf weight of ‘Lvling’בLiaoning NO.1’ were significantly greater than that of ‘Liaoning NO.1’× ‘Lvling’, which were respectively 56.43 cm2, 59.09 g/m2, the leaf index of ‘Lvling’ × ‘Lvzao’ was 1.94, which was significantly greater than that of ‘Lvzao’ × ‘Lvling’.6. 21 superior trees were primarily selected from the hybrid offsprings, principal component analysis methods were used to evaluate 13 traits of the 21 superior trees, such as fruits number, green husk rate, nut weight, yield per plant, kernel rate, average of 3 diameters, oil content, total protein content, dwarf index, disease resistance index, short bearing branch rate, internode length and the soluble protein content, and the superior trees were selected. The results showed that, according to the cumulative variance contribution which reached 74.3%, 4 principal components which reflected the main economic characters were determined; by calculating the comprehensive evaluation value of each plant, 3 superior trees from 21 superior trees were selected.