Photosynthetic Ecophysiologial Characteristics For Armeniaca Vulgaris Cv. Luntaibaixing In Oasis Habitat

Armeniaca vulgaris cv. Luntaibaixing is an ancient local fine variety of Luntai, native to the southXinjiang basin, with dried, fresh and open apricot stone processing of special variety with more than1,000years of cultivation history. Now it has become the main variety of the fruit industry in south Xinjiangbasin.Because of lacking in systematic study of the physiological and ecological characteristics for a longtime, resulting in a lack of in-depth understanding of its light utilization capacity in the oasis habitatconditions, which could affect taking advantange of its production and management. Therefore,this articletook artificial A.vulgaris cv. Luntaibaixing as the study object, under artificial cultivation in oasis habitat,and took photosynthesis of A.vulgaris cv. Luntaibaixing as the main line, combining the method of thefield live determination and indoor atatistical analysis,from the following aspects such as A.vulgaris cv.Luntaibaixing light response curve fitting and photosynthetic parameters estimates in different fruit growthperiods,the net photosynthetic changing rate under different weather conditions and its impact factors, anduse efficiency of instantaneous water were tested. The main conclusions are as follows:Though the light response curves of A.vulgaris cv. Luntaibaixing and photosynthetic parametersestimating, it showed that modified model of rectangular hyper bola was in accordance with the lightresponse process of A.vulgaris cv. Luntaibaixing.The light compensation（LCP）points were between16and56μmol·m^-2·s^-1, and the light saturation points（LSP）were between960and1,456μmol·m^-2·s^-1. As the fruitof A.vulgaris cv. Luntaibaixing gradually matured, the light saturation point of leaves showed a decliningtrend, but the maximum net photosynthetic rate and light saturation point showed a trend of rising.The photosynthetic physiological parameters of A.vulgaris cv. Luntaibaixing indicated that the diurnalchange of the net photosynthetic rate turned a two-peak pattern curve in sunnyday, with photosynthetic‘nap’ of A. vulgaris cv. Luntaibaixing caused by stomatal factors. The diurnal change of net photosyntheticrate showed a single peak curve in cloudy day, with no photosynthetic ‘nap’ phenomenon. The diurnalchanges of net photosynthetic rat was not stable in the overcast day, sometimes it assumed two-peakpattern curves, but sometimes it assumed unimodal curves. The daily mean value of A.vulgaris cv.Luntaibaixing leaf net photosynthetic was sunny day＞overcast day＞cloudy day in different fruit periods.The stepwise multiple regression and partial correlation analyzment showed that A.vulgaris cv.Luntaibaixing net photosynthetic rate was most closely related with the interaction of photosynthetic activeradiation and humidity in sunny day. However, its net photosynthetic rate was most closely related with theinteraction of photosynthetic active radiation and temoerature in sunny day.Water use efficiency in sunny day was fruit post-harvest period＞fruit maturity period＞fruit coloringperiod＞fruit hardcore period＞fruit enlargement period＞fruit set period,and water use efficiency incloudy day was fruit hardcore period＞fruit post-harvest period＞fruit coloring period＞fruit enlargementperiod＞fruit maturity period＞fruit set period. The caculation of water use efficiency of A.vulgaris cv.Luntaibaixing indicated water use efficiency in cloudy day was greater than it was in the sunny day.