绿洲与沙漠地带疏叶骆驼刺(Alhagi sparsifolia.)光合生理特征的适应差异

光系统Ⅱ的电子传递、生物量积累和形态变化三个方面对比研究了新疆石河子地区绿洲和沙漠生境下疏叶骆驼刺(Alhagi sparsifolia Shap.)光合生理特征的适应特点,发现两地Pn(净光合速率)特征值表现出清晨高,午后低的节律变化。沙漠生境下疏叶骆驼刺具有光饱合点高、蒸腾速率低和高水分利用率的特点,而绿洲生境下疏叶骆驼刺则通过较高的蒸腾速率来维持其高的光合速率,表现出高蒸腾、高光合的特点。二个样点Pn都与gs,WUE相关显著,而受Fv/Fm和水势变化的影响较小。认为疏叶骆驼刺对新疆沙漠和绿洲二种生境具有良好的环境适应性,并形成了不同的光合生理的适应特点;沙漠环境虽然不利于种群繁殖,但不影响疏叶骆驼刺的个体生长。

Differences of photosynthetic and physiological adaption between oasis and dersert on Alhagi sparsifolia

Gas exchange of Alhagi sparsifolia Shap.between oasis and desert were studied from three aspects,which are electron transferation,biomass accumulation and morphologic.The humidity is higher in desert than oasis because of the extent temperature changes,but the PPED is similar at the same time.we select the Unfolding leaf as object which come from 8 healthy plants.we using li-6400 to measure Pn,Gs,WUE(water using effect),E(Transpiration Rate) at each 2 hours,3 times and draw the diurnal courses of photosynthesis.For finding out the difference of adaption contrastively,we also measure the diurnal fluorescence after 20 minitue dark-adapted.leaf water potential(WP) is measure by PSYPRO.After measure above we take all plants back then meaure the biomass.We discovered that the rhythm of Pn(net photosynthetic rate) between oasis and desert is same,up in morning and lower at noon.The population of desert has higher light saturation,lower net of transpiration and higher WUE compare with the oasis population.The oasis population has higher transpiration to maintain the upper photosynthesis.Both in oasis and desert population,Pn and gs Pn and WUE,has significant correlation,but Pn is not affected by Fv/Fm and WP(water potential).We concluded that A.sparsifolia is very adaptive and form a difference photosynthetic characters,the desert habitation is not suit to propagation,but in not affect the growth.