Study On Biology Characteristics,Photosynthetic Characteristics And Cold Resistance Of Xin Jiang Wild Almond

In this experiment,5 different population wild almond, Yuming, Tuoli, Buerjin, Tacheng and Habahe were chosen as research materials to observe the phenophase, characteristics of growth and development, floral organ characteristics and fruit characteristics; By using Li-6400 photosynthesis system, the net photosynthetic rate, stomatal conductance, intercellular CO2 concentration and transpiration rate of wild almond were measured as well as their light response. In winter, the wild almond branches were treated at low temperature to measure the contents of soluble sugar, starch, MDA, soluble protein, SOD activity, POD activity and changes of the relative conductivity, then the recovery growth experiment was carried out to compare their resistance with the method of membership function. The results showed that:(1) As for the growth period, all the five populations were around 150 d, and the biological characteristics and growth habits demonstrated obvious difference in different populations of wild almond. The new shoots, leaf width, plant height and the ground diameter of Tacheng population were the largest, but the blade thickness was the smallest; As for the fruit kernel, Tuoli population was the longest in the length, Habahe population was the shortest in the length and the minimum in the weight of hundred seeds, Tacheng population were the largest in the width and thickness, and Burjin population were the minimum in the width and thickness.(2) The growth dynamic curve of plant height of wild almond showed a trend of "S", while the growth dynamic of ground diameter exhibited as "uniform growth". As for the cumulative growth, Tacheng population was the least in plant height, but the largest in ground diameter; Burjin population were the maximum in height plant, and Habahe population were the minimum in ground diameter.(3) The results showed that the leaf Pn of these 5 different population wild almond presented bimodal curve, and the midday depression of photosynthesis appeared at 14:00; Net photosynthetic rate and transpiration rate both appeared significant difference. Stomatal conductance presented extremely significant difference, and there was no difference in intercellular CO2 concentration. Tacheng group had the max value on net photosynthetic rate, Tuoli group had the minimum value on net photosynthetic rate, the other group in center.(4) As the light increased, the photoresponse curve of different wild almond groups had different rising, intercellular CO2 concentration had different degrees of decline, and stomatal conductance and transpiration rate presented slowly rising. Tacheng group had the strong ability to use weak light, and had the max value on net photosynthetic rate at 15001x light intensity, but had the minimum value on R<d, had the highest light saturation point, and presented strong photosynthetic capacity.(5) The relative conductivity presented "S" curve with decreasing of temperature, the contents of starch, soluble protein, MDA, soluble sugar content changed from falling to rising, SOD activity and POD activity changed from rising to falling. The results of membership function values and recovery growth results suggested that the order of cold resistance as follow:Habahe>Tacheng>Buerjin>Yumin>Tuoli.