Effects Of The Survival Rate And Growth On The Different Combinations In Carya Nutt

Recently, pecan has developed rapidly in China due to its high nutrition and economic value. There are 18 species in Nutt Carya, mainly distributed in eastern North America and Southeast Asia, especially C.cathyensis, C.hunanensis and C.illinoensis. With failure to break through the breeding difficulties, the pecan didn’t spread on a large scale. After the breakthrough of crucial technique in the grafting, the graft compatibility has become the most important factor affecting the survival rate of grafting. In recent years, though pecan is developing rapidly in China, which has not been reported in graft compatibility. Therefore, the affinity of Carya species was studied in different scion/rootstock combination of C.cathyensis,C.hunanensis, C.illinoensis, and the affinity of C.illinoensis species was studied in different scion/rootstock combination of Shaoxing No. 1,No. 64, No. 35, Ma Han and Weston. The germination rate, survival rate, growth index, leaf paraffin, light response curve, photosynthetic physiological parameters, the chlorophyll fluorescence parameters, relative chlorophyll content determination were studied in the Carya interspecific grafting affinity differences, can rich its advanced species and provide scientific evidence for the further promotion. The result indicate:1. The germination rate among the Carya interspecific graftingWhen hunanensis and illinoensis were rootstock, its Germination rate were highest,respectively 80.26% and 78.52%, and hunanensis rootstock can improve the cathyensis scion germination rate(increase by 12%).2. The growth index among the Carya interspecific graftingIllinoensis rootstock can promote the growth of cathyensis and hunanensis, llinoensis should not be grafted on to cathyensis and hunanensis;3. The photosynthetic physiological parameters among the Carya interspecific graftingThe Amax of illinoensis rootstock were significantly higher than in cathyensis and hunanensis rootstock, illinoensis rootstock can improve the Amax and AQY in cathyensis scion.The LSP of illinoensis rootstock were significantly highest.Hunanensis rootstock grafted on cathyensis can increase LSP.4. The palisade tissue among the Carya interspecific graftingIllinoensis grafted illinoensis seedlings’ palisade tissue was thick(145.665μ m), the plants use light energy efficiency was higher.illinoensis rootstock make cathyensis and hunanensis scion palisade tissue thicker.5. The pchlorophyll fluorescence parameters among the Carya interspecific graftingIn a rapid fluorescence curve, Y(II) in illinoensis grafted illinoensis scion was significantly higher than that of other combinations;Y(NPQ) in hunanensis grafting on cathyensis rootstock was the highest; regarding to ETR, when grafted on hunanensis rootstock, hunanensis scion and cathyensis scion was significantly higher than that of illinoensis scion.So cathyensis and hunanensis grafting compatibility were the better.The results also showed that when illinoensis(rootstock) was grafted cathyensis and hunanensis respectively,the graft compatibility was good,while cathyensis and hunanensis(rootstock) respectively was grafted illinoensis,the graft compatibility was poor.6. The germination rate among the C.illinoensis intraspecific graftingThe germination rate and Survival rate of Shaoxing No. 1 rootstock grafting Shaoxi ng No. 1 scion,Shaoxing No. 1 rootstock grafting No. 64 scion, Shaoxing No. 1 rootst ock grafting No. 35 scion, Shaoxing No. 1 rootstock grafting Ma Han scion and Shaoxi ng No. 1 rootstock grafting Weston scion have no significant difference. The germinatio n rate of Shaoxing No. 1 rootstock grafting Shaoxing No. 1(82.20%)have higher sign ificant difference than Ma Han rootstock grafting Shaoxing No. 1 scion(60.00%);The survival rate of No. 35 rootstock grafting Shaoxing No. 1 scion was75.33%,have highersignificant difference than Shaoxing No. 1 rootstock grafting Ma Han scion( 54.67%)and Ma Han rootstock grafting Shaoxing No. 1 scion(55.67%).7. The growth index among the C.illinoensis intraspecific graftingA new growth amount of Shaoxing No. 1 rootstock grafting No. 64 scion(39.957cm),Shaoxing No. 1 rootstock grafting No. 35 scion(39.254cm),have higher significant di-fference than the rest combination.Shaoxing No.1 rootstock grafting Ma Han scion was the lowest(19.552cm) and Shaoxing No. 1 rootstock grafting Weston scion have no signi ficant difference.8.The photosynthetic physiological parameters among the C.illinoensis i-ntraspecific graftingThe Amax and AQY of Shaoxing No. 1 rootstock grafting No. 35 scion,have highersignificant difference than the rest combination,and Ma Han rootstock grafting shaoxingNo. 1 scion was the lowest.9.The pchlorophyll fluorescence parameters among the C.illinoensis intraspecific graf tingThe Fv/Fm of No.35 rootstock grafting Shaoxing No.1 scion,have higher significant difference than the rest combination,and shaoxing No. 1 rootstock grafting Mahan scion was the lowest.So the graft compatibility of No.35, No.64 and Shaoxing No.1 were the better.Theresults also showed mahan and Shaoxing No.1 was poor.