Preliminary Study On Distant Hybridization Of Acer Sinense Pax×Acer Palmatum Thunb And Hybrids Identification

Acer sinense Pax and Acer palmatum Thunb are belong to the Aceraceae group on the taxonomy, having close relatives. Both are important ornamental in color of Acer Linn. They are beautiful in leaf shape and color; having polygamous flowers, samara expands into obtuse or acute angle; the shape of tree is elegant; they are an important ornamental tree in landscape.Acer sinense Pax has better orthostatic branches, but not much application in the northern region. Its leaf color is single, ornamental period is shorter, and often accompanied by plant diseases and insect pests, poor adaptability when it was planted in the north. Acer palmatum Thunb has relatively flat branches and variety of leaf color. Its leaf is smaller than the Acer sinense Pax, but has strong adaptability, widely applied in northern region. By distant hybridization, in order to get erect branches, colorful leaf, elegant leaf shape, high adaptability,high ornamental value, setting both advantages in hybrids, creating new heterocyst.The experimental materials taken from Shandong agricultural university campus of the Acer sinense Pax and Acer palmatum Thunb, This paper mainly include the following several aspects: The first was the Acer sinense Pax pollen technology, including the best measurement time of the pollen germination in vitro culture; the rapid determination method of the pollen vigor, the choice of pollen culture 0conditions, the choice of pollen storage conditions, etc; the second was Acer palmatum Thunb,including the choice of the Acer palmatum Thunb pollen in vitro culture condition; The third was the distant hybridization research between Acer sinense Pax and Acer palmatum Thunb, mainly including reciprocal cross; the fluorescence microscopic observation after pollination of pollen tube behavior and obstacle of hybrid technology. The main results were as follows:(1) Single factor such as sucrose, boric acid and calcium chloride has remarkable effect on pollen germination of the pollen of Acer sinense Pax, in vitro culture after 16 h, the suitable single factor for pollen germination of Acer sinense Pax was: 100 g/L sucrose; 50 mg/L boric acid; 30 mg/L Calcium chloride.In vitro culture method, I2- KI, TTC and acetate magenta,the 4 method of in vitro culture of the pollen Acer sinense Pax germination rate is highest, and lowest TTC method, the most close to the Acer sinense Pax pollen germination in vitro culture method is I2- KI method, and significant difference in vitro culture method, themethod of acetate magenta is not suitable for the Acer sinense Pax pollen activity assay. In vitro culture is the most suitable for the determination of real Acer sinense Pax pollen vitality.The Acer sinense Pax pollen storage at room temperature, 4℃and 20℃ condition respectively,the results show that at room temperature, pollen viability of Acer sinense Pax can live at most 10d; under the condition of 4℃ for 60d; under the condition of- 20℃ can store 120 d.(2) Different concentrations of sucrose 、 boric acid has a different effect on pollen germination of Acer palmatum Thunb, in the certain concentration range, with the increase of concentration of sucrose and boric acid, the pollen germination rate also will increase; but beyond a certain range, the pollen germination rate changes, suitable for Acer palmatum Thunb pollen germination of sucrose and boric acid composition is: 15% sucrose + 0.05%boric acid.(3) Acer sinense Pax × Acer palmatum Thunb, observation with fluorescent microscope Found that Acer palmatum Thunb can be adhesive on the stigma of Acer sinense Pax and germination, pollination 12 h a lot of pollen germination when 12 h after pollination, 48 h after pollination, pollen tube can be extended to the style of 1/4, but growth retardation, can’t reach ovary completed fertilization. Take repeated pollination, GA3 treatment head, cutting styles and mixed pollination. etc; although repeated pollination can increase the quantity of pollen germination, but only GA3 treatment head got 7 hybrids, the rest of the way has not been the ideal effect. Hybrid seedlings is similar to parents in the leaf length, leaf crack and the leaf color more inclined to their mothers, and take further measures, that was ISSR molecular marker identification, found that hybrids are more inclined to Acer sinense Pax.(4) Acer palmatum Thunb ×Acer sinense Pax, put the pollen of Acer sinense Pax that store a year later after- 80 ℃ daub to Acer palmatum Thunb stigma; did not find the pollen of Acer sinense Pax germination. Repeated pollination, cutting head and the way of GA3 treatment head, there is still no hybrid seeds, there are serious reproductive isolation in inverse cross.