This paper studied the effects of cinnamon acid treatments on the respiratory rate and related enzymes activity in the seedling roots of Malus hupehensis Rehd.It would provide information for understanding the mechani...This paper studied the effects of cinnamon acid treatments on the respiratory rate and related enzymes activity in the seedling roots of Malus hupehensis Rehd.It would provide information for understanding the mechanisms of inhibition damage caused by continuous cultivation of apple tree.20 mL of solution containing different concentrations of cinnamon acid was added into container with the tested seedlings.After treatment,the samples were taken periodically and the respiratory rates were measured by OXY-LAB oxygen electrodes under 25°C stable temperature and then the activities of related enzymes were measured.The rates of total respiration and other 2 pathways [tricarboxylic acid cycle （TCA） and pentose phosphate pathway （PPP）] appeared initially an increasing treads and late （on the 3rd d） began to decline.However,they again appeared an increase trend at the end period,on the contrast,the respiratory rate of embden-meyer- hot-parnas （EMP） pathway appeared a stead decline tread but it had a recover on the last day.The respiratory rate of total and 3 pathways were decreased under 125 mg kg-1 （soil）.The dynamic trends of the enzymes activities of pyrophosphate-dependent phosphofructokinase （PFK）,glucose-6-phosphate dehydrogenase （G-6-PDH） and malate dehydrogenase （MDH） showed similarly.In conclusion,treatments of certain concentration of cinnamon acid would inhibit the respiratory rate and related enzymes activity of roots of M.hupehensis Rehd.And the inhibition degrees were positively related with concentration of cinnamon acid treatments.展开更多
Root border cells （RBCs） originate from the root tip epidermis and surround the root apices. In this study, we evaluated the developmental characteristics and the roles of RBCs in protection of root apices of cucumb...Root border cells （RBCs） originate from the root tip epidermis and surround the root apices. In this study, we evaluated the developmental characteristics and the roles of RBCs in protection of root apices of cucumber and ifgleaf gourd seedlings from CA toxicity. The formation of RBCs and the emergence of the root tip occurred almost simultaneously in root apices of cucumber and ifgleaf gourd seedlings. CA ranging from 0 to 0.25 mol L-1 inhibited root elongation and decreased root cell viability in the root tip, moreover the inhibitory effects of CA were more signiifcant in the CA-sensitive cucumber than in the CA-tolerant ifgleaf gourd. Removal of RBCs from root tips led to more severe CA induced inhibition of root elongation and decline in root cell viability. Increasing CA levels and treatment time decreased the relative viability of attached and detached RBCs. CA also induced a thicker mucilage layer surrounding attached RBCs of both species. Additionally, a signiifcantly higher relative cell viability of attached RBCs and thicker mucilage layers were observed in ifgleaf gourd. These results suggest that RBCs play an important role in protecting root tips from CA toxicity.展开更多
基金suppoted by the Project of 948 from Ministry of Agriculture of China (2006-G28)the Non-profit Research Foundation from Ministry of Agriculture of China (nyhyzx07-024)+1 种基金the Ear Marked Fund for Modern Agro-Industry Technology Research System, Chinathe Key Innovation Project for Agricultural Application Technology of Shandong Province, China.
文摘This paper studied the effects of cinnamon acid treatments on the respiratory rate and related enzymes activity in the seedling roots of Malus hupehensis Rehd.It would provide information for understanding the mechanisms of inhibition damage caused by continuous cultivation of apple tree.20 mL of solution containing different concentrations of cinnamon acid was added into container with the tested seedlings.After treatment,the samples were taken periodically and the respiratory rates were measured by OXY-LAB oxygen electrodes under 25°C stable temperature and then the activities of related enzymes were measured.The rates of total respiration and other 2 pathways [tricarboxylic acid cycle （TCA） and pentose phosphate pathway （PPP）] appeared initially an increasing treads and late （on the 3rd d） began to decline.However,they again appeared an increase trend at the end period,on the contrast,the respiratory rate of embden-meyer- hot-parnas （EMP） pathway appeared a stead decline tread but it had a recover on the last day.The respiratory rate of total and 3 pathways were decreased under 125 mg kg-1 （soil）.The dynamic trends of the enzymes activities of pyrophosphate-dependent phosphofructokinase （PFK）,glucose-6-phosphate dehydrogenase （G-6-PDH） and malate dehydrogenase （MDH） showed similarly.In conclusion,treatments of certain concentration of cinnamon acid would inhibit the respiratory rate and related enzymes activity of roots of M.hupehensis Rehd.And the inhibition degrees were positively related with concentration of cinnamon acid treatments.
基金supported by the National Basic Research Program of China(973 Program2009CB1190002)the National Key Technology R&D Program of China(2011BAD12B01)
文摘Root border cells （RBCs） originate from the root tip epidermis and surround the root apices. In this study, we evaluated the developmental characteristics and the roles of RBCs in protection of root apices of cucumber and ifgleaf gourd seedlings from CA toxicity. The formation of RBCs and the emergence of the root tip occurred almost simultaneously in root apices of cucumber and ifgleaf gourd seedlings. CA ranging from 0 to 0.25 mol L-1 inhibited root elongation and decreased root cell viability in the root tip, moreover the inhibitory effects of CA were more signiifcant in the CA-sensitive cucumber than in the CA-tolerant ifgleaf gourd. Removal of RBCs from root tips led to more severe CA induced inhibition of root elongation and decline in root cell viability. Increasing CA levels and treatment time decreased the relative viability of attached and detached RBCs. CA also induced a thicker mucilage layer surrounding attached RBCs of both species. Additionally, a signiifcantly higher relative cell viability of attached RBCs and thicker mucilage layers were observed in ifgleaf gourd. These results suggest that RBCs play an important role in protecting root tips from CA toxicity.
