Influence of Water Stress on the Seedling Growth and Physiological Characteristics of Parakmeria latungensis
LI Yuan-fa et al(Forestry College of Guangxi University,Nanning,Guangxi 530005)
[Objective] The research aimed to investigate the physiological and growth index changes of Parakmeria lotungensis under different water stress conditions.[Method] With potted seedlings of P.lotungensis as tested material,setting 5 treatments of water stress,i.e.10%,20%,40%,60% and 80% of field capacity,the effect of water stress on seedling growth of P.lotungensis was studied.[Result] The relative increments of seedling height and basal stem diameter,chlorophyll content and root activity of P.lotungensis were increased with the rising of soil moisture,their maximum value was reached when the soil moisture content was 60% of field capacity,being 13.67%,15.04%,1.45 mg/g,50.89 mg/(g·h) resp.,and then began to decline,the 4 growing indexes were fallen to 2.88%,5.56%,1.086 mg/g,and 25.252 mg/(g·h) resp.when the soil moisture content was 80% of field capacity.The variation trend of free proline content in leaves was just opposite,as the soil moisture contents were 60% and 80% of field capacity,the free proline content reached the minimum of 0.008 μg/ml and maximum of 0.053 μg/ml resp.[Conclusion] It was suitable for growing of P.lotungensis seedlings when the soil moisture content was 60% of field capacity.