5种丛枝菌根真菌对君迁子幼苗光合生长的影响

Effects of inoculating different kinds of AMF on growth of seedlings in Diospyros lotus

为了探明丛枝菌根真菌对君迁子生长及光合作用的影响,以分别接种了细凹无梗囊酶（Acaulospora scrobiculata,简称AS）、聚丛根孢囊酶（Rhizophagus aggregatus,简称RA）、扭形多样孢囊酶（Diversispora trotuosa,简称DT）、根内根孢囊酶（Rhizophagus intraradices,简称RI）、摩西斗管囊酶（Funneliformis mosseae,简称FM）等5种丛枝菌根真菌和未接种菌根真菌的君迁子幼苗为试材,对6种处理下君迁子幼苗的生长情况和叶片的主要光合指标进行了观测,并用双曲线修正模型对所测数据进行拟合,得到光合响应曲线及各处理下君迁子幼苗各光合特征参数。结果表明：①菌根化的君迁子幼苗其株高、地径、叶片数、植株鲜质量等指标值均有明显的提高,与未接种的对照组相比,接种AS、RA、DT、RI、FM使君迁子的株高分别提高了48.22%、62.01%、14.34%、14.66%、29.01%;其地径分别提高了22.81%、46.84%、21.19%、17.23%、14.72%;其植株鲜质量分别提高了93.69%、103.93%、53.98%、68.52%、84.44%;其单株叶片数比对照组多2~5片。②菌根化的君迁子幼苗其净光合速率、光饱和点均高于对照组,而其光补偿点则反之。③各接种处理的净光合速率的日变化趋势较为一致,均呈“双峰”曲线,12：00~14：00时均存在“午休”现象,但接种处理下君迁子幼苗叶片的净光合速率、气孔导度、蒸腾速率、水分利用率的日均值均高于对照组。研究结果表明：接种丛枝菌根真菌能够显著提高君迁子幼苗的净光合速率,改善其对光的适应性,对植株的生长有显著的促进作用,但促进作用因菌种而异。

In order to ascertain the effects of AMF on growth and photosynthesis of Diospyros lotus, taking seedlings in D. lotus as materials, which were infected by five kinds of AMF, Acaulospora scrobiculata （AS）, Rhizophagus aggregatus （RA ）, Diversispora trotuosa （DT）, R. intraradices （RI）, and Funneliformis mosseae （FM）, growth indexes and main photosynthetic indicators of the materials and CK were determined. The photosynthetic response curves and photosynthetic characteristic parameters of the seedlings in the treatments, through fitting hyperbolic correction model. The results showed that infection of AMF significantly increased the growth indexes of seedling compared with CK, including seedlings height, ground diameter, leaf number and fresh mass per plant. In the AS, R.A, DT, RI, and FM treatments, seedling heights were respectively enhanced by 48.22%, 62.01%, 14.34%, 14.66%, 29.01%; ground diameters were respectively increased by 22.81%, 46.84%, 21.19%, 17.23%, 14.72%; fresh mass per plant were respectively increased by 93.69%, 103.93%, 53.98%, 68.52%, 84.44%; leaf number were increased by 2-5 pieces. Net photosynthetic rates and light saturation points were higher compared with CK, but light compensation points were lower. The diurnal variation trends of net photosynthetic rates of the treated seedlings were consistent, and the diurnal variations were typical bimodal curves with midday depression of photosynthesis during 12：00-14：00. The net photosynthetic rate recovered more quickly than CK after the midday depression. And the diurnal mean values of net photosynthetic rate, stomatal conductance, transpiration rate and water use efficiency were higher than CK. AMF could increase net photosynthetic rate, improve photosynthetic adaptability of seedlings, and promote growth of seedlings. But different AMF had different promote effects on seedlings growth in D. lotus.