Studies on Electrolyte Conductivity and Activity of Dehydrogenase of Chinese Fir and Masson Pine Bare—Root Seedling under Water and Cold Stress     

YuFangyuan XuXizeng GuoXinbao 《中国林学(英文版)》2003,5(1):30-33

The electrolyte conductivity and activity of dehydrogenase of bare-root seedlings of both Chinese fir (Cunninghamia lanceolata (Lamb.)Hook.)and Masson pine (Pinus massoniana Lamb.) under freezing and desiccation treatments were studied.The results showed that needle electrolyte conductivity of both speices increase significantly after freezing treatment and there are no significant differences in needle electrolyte conductivity between the two species.The dehydrogenase activity(ARD) of fine roots of both Chinese fir and Masson pine was negatively correlated with increasing freezing and desiccation.The results suggest that both electrolyte conductivity and dehydrogenase activity could be used as quick indicators of Chinese fir and Masson pine bare-root seedling quality.  相似文献   

重茬苹果园土壤理化性质变化及对幼树生长结果的影响     

杭波  韩青海  李庆军  原永兵  刘成连 《安徽农业科学》2011,39(21):12732-12734,12738

[目的]采用矮化密植栽培模式,添加土壤有机改良肥,以减轻重茬障碍对新定植苗的危害。[方法]以22年生老果园重茬改造园内的土壤和再植苗为试材,连续2年研究果园土壤养分、土壤酶活性以及再植苹果树生长量、产量。[结果]果园重置前的有机质含量在2g/kg左右,2009年达到10g/kg以上,2010年又降到5～9g/kg。这说明土壤的有机质正在转化吸收。定植前老果园的碱解氮含量大多在120～150mg/kg,速效磷含量150mg/kg,速效钾含量80～90mg/kg,80%的土壤样本pH低于5.5;2009年土壤碱解氮含量、速效磷含量变化并不大,速效钾含量在470mg/kg左右,全部土壤样本的pH都高于5.5;2010年土壤样本的碱解氮含量100～120mg/kg,速效磷含量30mg/kg,速效钾含量降到200～300mg/kg,80%土壤样本的pH在6.0以上。2010年苹果幼树平均开花率达649.2个/株,2009年却达74.5个/株;2010、2009年苹果单果重不存在差异,多在195.5g左右;2010年苹果单果重达200g,果树产量最高达40669.5kg/hm2。[结论]改良后的土壤有机质及N、P、K的含量均有所增加,在随后的2年内有机质及N、P、K含量降低;定植后的幼树生长良好,2010年已进入平稳的丰产期。  相似文献