| Material problem is key factor of expanding Xanthoceras sorbifolia Bunge ecological energy sources forest. That is lack of Xanthoceras sorbifolia resource with high yield and oil content traits. Based on this, since 2006 the research analyzed Xanthoceras sorbifolia populations Inner Mongolia WQ and AQ of western song-liao plain,San menxia Sanxian of western Henan mountain and Cheng De of north Hebei mountain area. Established excellent traits synthesis evaluation index system. Selected super forest, super type and plus trees. Main results are as follows:(1)Established excellent traits synthesis evaluation index system. The research established rules for super forest selection. Index system contains 1 objective layer, 3 control layers and 10 indexes. Index system meets the demand for selecting super forest. 5 super forests with super growth traits and economic traits were selected by the index system.(2)Site factors had different effect on Xanthoceras sorbifolia forest growth and fruiting traits. Partial correlations analysis showed slope direction, slope position and soil thickness had significant effect on Xanthoceras sorbifolia growth and yield. The result showed Xanthoceras sorbifolia should be planted where soil was thick, slope gradient was little, lee slope and exposure to the sun, neutral or alkalescence sand soil region. In mountainous region it should be planted in south slope’s middle, or lower part, or mountain bottom. Slope gradient should be less than 30°.The effect of different plant density on Xanthoceras sorbifolia growth and yield was investigated. Plant density should be decided by site condition and management method. In mountain and sandy land with less fertilizer the density can be(1~3)m×(2~3)m in order to increase yield per square meter. In fertile loess hilly the density can be 3m×4m or 4m×4m. In area with thick soil and easy to irrigate and fertilize the density can be 5m×5m. The vacant land can be used for intercropping.(3)The research studied Xanthoceras sorbifolia population genetic diversity with AFLP technique. 15 primer combinations amplified 557 bands. Polymorphic bands rate was 66.39%. Average Shannon information index of 5 populations was 0.522. Average Nei’s gene diversity index of 5 populations was 0.3773. 2 indexes sequence from high to low was SX>KD>WQ>CD>DS. 6.61% of total genetic variation was between populations, and 93.39% was within populations. Gene flow was 7.0621. Based on genetic distance clustering WQ and KD were classified into one type, DS and SX were classified into one type, CD was one type.(4)In super forest Xanthoceras sorbifolia was divided into different types based on tree shape, branches, leaves, flowers, fruits and seeds. Xanthoceras sorbifolia was divided into simple flower and double flower based on flower character. Simple flower includes simple white flower type and simple red flower type. Based on fruit trait simple white flower type was classified into small spherical fruit type, big spherical fruit type, cylindrical fruit type, triquetrous fruit type, flat-sphere fruit type, peach fruit type and obovate fruit type. Simple red flower type’s yield was very low. Double flower included double purplish red flower type and double yellow flower type. Double flower type doesn’t bear fruit. Based on ornamental and economic value Xanthoceras sorbifolia was divided into fruiting type and flowering type. Fruiting type was simple white flower type. Flowering type included simple red flower type, double purplish red flower type and double yellow flower type. The research investigated each type’s distribution rate, biological characters, economic traits, growth, fruiting and phenophase.(5)Established super type synthesis evaluation index system and classifying standard. Index system contains 1 objective layer, 5 control layers and 19 indexes.Calculated each type’s score. Super types suit for different area were selected based on score and super type choosen rules. In Inner Mongolia WQ of western song-liao plain big spherical fruit type, triquetrous fruit type and cylindrical fruit type were super types. In Inner Mongolia KD and DS of western song-liao plain small spherical fruit type, big spherical fruit type and cylindrical fruit type were super types. In San menxia Sanxian of western Henan mountain big spherical fruit type and cylindrical fruit type were super types. In Cheng De of north Hebei mountain area small spherical fruit type, big spherical fruit type, flat-sphere fruit type and cylindrical fruit type were super types. The paper summarized super types’ area suitable for growing, forest type and site type.Seedling traits of simple white flower obovate fruit type and simple white flower peach fruit type were lower. Super type simple white flower big spherical fruit type, triquetrous fruit type and cylindrical fruit type’s growth traits were higher than small spherical fruit type and flat-sphere fruit type. There was obviously variation between types’ seedling traits.(6)Beside some plants don’t bear fruit, reason of low fruit setting rate of Xanthoceras sorbifolia is 2 years branch’s terminal inflorescences grow female flowers and lateral inflorescences grow male flowers. Male flowers are much more than female flowers.The result of different distributions and forests flowering and fruit setting traits investigation showed the number of fruit set and fruit setting rate of simple white flower type were higher than simple red flower type. Super types’ fruit setting rates were medium in every distribution and forest. The reason maybe the process of flowering and fruit setting goes on with new branch and leaves growing at the same time. This period needs much nutrition. Medium level fruit setting rate was good for keeping nutrition balance. Average fruit setting rate was highest(5.22%) in Inner Mongolia WQ of western song-liao plain.(7)This research established method and standard of plus tree selection. In WQ, KD, DS, SX, YX and CD populations 258 high yield trees were selected. 164 trees with high oil content were selected. 229 trees with super economic traits were selected altogether. Plus trees’ growth, fruit traits, seed oil content were obviously better than other trees of population.Ahp method was used to select trees with super synthesis traits. The research established individual traits classfication standard. 92 trees with excellent synthesis traits were selected.(8)Plus trees’ growth and fruit traits of different site condition, forest type and distribution were compared. Belonging to low mountain hilly south slope thick soil, sub concentrated distribution pure forest, CD plus trees’ growth traits were highest. Belonging to hilly platform chestnut soil, concentrated distribution pure forest, DS plus trees’ oil yield per m2, seed oil content, seed rate were highest. Belonging to low mountain hilly south slope thick soil, sub concentrated distribution pure forest, CD plus trees’ seed yield were highest. Belonging to low mountain south slope thin soil, concentrated distribution mixed forest of Xanthoceras sorbifolia, Robinia psedoaccia and Z.jujuba, SX plus trees’ seed yield were higher. Belonging tomidium mountain south slope thick soil, sub concentrated distribution pure forest, YX plus trees’ weight per 100 fruits, fruit and seed size and seeds number per fruit were highest.(9)There were obviously variation between plus tree progenies height, basal diameter, taproot length and biomass. The traits differences between provenances were significant. Genetic parameters were analysised. 43 super families were selected based on genetic gains.(10)Factors affected yield were mainly crown width, weight per 100 fruits, height and seed length. Fruit length, width, seed width and seeds per fruit also had obvious effect. |
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