Study On The Effects Of Xenia In Vernicia Fordii And Variety Combination Optimization

The Tung oil tree(Vernicia fordii(Hemsl.))is an important oil plant for the use of industry in China.The tung oil produced from its seeds is excellent dry oil.It is one of the main industrial oil and widely used in paint,plastics and other manufacturing industries.But at present,the tung oil industry is facing many problems such as single forest species and low yield.It is of great significance to study the genetic breeding of Tung oil tree.Many studies have shown that for monoecious and cross-pollinated economic forest crops,different varieties can be used to improve yield or quality.However,it is not known whether similar phenomena exist in Tung oil trees.In this study,some production characters of three improved varieties of Tung oil tree(Xiaomi,Putao and Dami)widely planted in Chongqing were analyzed.The flowering phenophases of three varieties were observed and the hybridization experiments were performed.The high-yield hybrid combinations were selected through the analysis of fruit setting rate,yield,oil content and other indicators.The contents of this study are as follows: To master the biological and ecological characteristics of three improved Tung oil tree varieties by studying their characteristics and adaptability.The observation of flowering phenology,the percentage of female flowers,the amount of pollen,the activity of pollen.To analyze whether the fruit setting rate of Tung oil tree has the direct effect of pollen through the cross test of different varieties.To analyze whether each character of Tung oil tree has obvious pollen direct effect by collecting the fruit,observing the fruit character and seed character,extracting tung oil,and measuring the quality of tung oil of each hybrid combination.On the basis of accurately grasping the biological and ecological characteristics of different varieties,the optimal configuration combination of Tung oil tree varieties was screened.This provides a combination of pollination tree configuration for production,so that cross pollinated Tung oil tree can be given pollen with good affinity,thus improving the yield of tung oil.Based on the above studies,the following research results were obtained: Xiaomi,Putao and Dami are similar in flowering period.It was feasible to pollinate each other when they were mixed.The statistics of pollen quantity showed that the amount of single anther pollen,the number of single flower anthers,and the number of single flower pollen grains of millet are the most among the three,which can be considered as pollinating varieties.The results of pollen activity test showed that the pollen activity of Xiaomi and Putao was slightly higher than that of Dami,but there was no significant difference among the three.The pollen vigor of the varieties meets the requirements of cross pollination.By comparing the flowering characters,fruit characters and tree characters of the three varieties,it was found that the female flower proportion,fruiting branch proportion,fruit cluster proportion,number of fruit per plant and yield per plant of Putao were the highest among the three varieties;the single fruit weight of the Dami was the highest;the tree structure of the Xiaomi and Putao was compact.According to the statistical results of flowering,fruit and tree characters,Putao is the most suitable variety for planting in Chongqing.Through the hybridization of three Tung oil tree varieties,we found that there was obvious pollen direct effect in Tung oil tree,which affected fruit or seed characters such as fruit setting rate,fresh single fruit weight,transverse diameter,dry single seed weight,dry single kernel weight,dry kernel yield and kernel oil content.This study finally screened two high-yielding species combinations:“?Putao × ?Xiaomi” and “?Putao × ?Dami”.The results of hybridization experiments showed that the fruit setting rate,fresh single fruit weight,transverse diameter,dry single seed weight,dry single kernel weight and kernel ratio had obvious xenia effect.The fruiting rate(increased by 4.81%),single fruit weight(increased by 13.34%)and oil yield(increased by 8.56%)of Putao were significantly increased when Xiaomi was used as pollination variety;in the same way,the above-mentioned indexes of Putao were significantly improved by using the Dami as the pollination variety,in which the fruit setting rate increased by 7.70%,the single fruit weight increased by 27.80%,and the oil yield increased by 14.26%.The quality of tung oil was not significantly affected when Xiaomi or Dami was used as pollination variety.The results of this study show that: the reasonable planting of Putao,Dami and Xiaomi with the same flowering phenology can further improve the fruit setting rate,single fruit weight,kernel oil content and other indicators of the most suitable variety Putao,which can significantly improve the tung oil yield per unit area.This provides a new planting mode for the future to solve the problems of the lack of resources,low per unit yield and backward high-yield cultivation technology.