[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to d...[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to differentiate the degrees of drought stress based on changes in soil water content and leaf water potential and investigate variations in contents of osmotic regulation substances（free proline,soluble sugar and soluble protein） in leaves of five Catalpa bungei clones under different degrees of drought stresses. [Result] According to changes in soil water content and leaf water potential, the whole process of drought stress was divided into normal level（CK, with soil water content of 97.49% and leaf water potential of-0.54MPa）, light drought（LD with soil water content of 59.96% and leaf water potential of-1.28 MPa）, mediate drought（MD with soil water content of 34.19% and leaf water potential of-2.32 MPa） and severe drought（SD with soil water content of 14.52%and leaf water potential of-2.99 MPa）. The soil water content and leaf water potential of five Catalpa bungei clones reached the highest correlation in exponential fitting, with an average R2of 0.989 3（P0.001）. The free proline content in leaves of five Catalpa bungei clones increased rapidly with the increasing degree of drought stress（P 0.001）. To be specific, free proline contents of Catalpa bungei clones015-1 and 7080 were 34.39 and 33.41 times of the normal level under severe drought conditions, which reached an extremely significant level（P0.001）; the free proline content of Catalpa bungei clone 1-3 rapidly increased to（855.46±227.52） μg/g Fw under light drought conditions. The soluble protein content in leaves showed different variation trends. To be specific, the soluble protein content of Catalpa bungei clone 7080 was the lowest at various drought stages and reached（1.644 ±0.137）mg/g Fw under normal conditions; the soluble protein content of Catalpa bungei clone 1-3 was relatively high under normal conditions and was reduced rapidly under light drought conditions, showing different response patterns. [Conclusion] Osmotic regulation substances in leaves of five Catalpa bungei clones all have certain response to drought stress. Free proline is the most important osmotic regulation substance, followed by soluble protein, while soluble sugar makes no significant contribution. According to changes in content of osmotic regulation substances, Catalpa bungei clone 7080 has relatively high capacity and good drought resistance, while Catalpa bungei clone 1-3 has the rapidest response to drought stress.展开更多
In order to study the growth traits of Catalpa bungei clones in various growth periods during the nursery stage so as to provide a theoretical basis for genetic improvement,the authors matched the height and diameter ...In order to study the growth traits of Catalpa bungei clones in various growth periods during the nursery stage so as to provide a theoretical basis for genetic improvement,the authors matched the height and diameter in nursery stage by Logistic equation.The results showed that the mean height of clones was 325.19 cm,with the range of 253.48-402.88 cm,the mean basal diameter of clones was 4.29 cm,with the range of 3.61-5.05 cm.The height increment could be divided into two stage,i.e.the early-growing period and the fast-growing period,while the basal diameter increment could be divided into three stage,i.e.the early-growing period,the fast-growing period and the late-growing period.The beginning of fast-growing period,the end of fast-growing period,the duration of fast-growing period,and the daily mean height increment in fast-growing period were May 26-July 2,September 11-October 15,72-128 days,and 1.70-2.88 cm,while that for basal diameter increment were May 9-June 5,August 23-October 3,95-138 days,and 0.021-0.032 cm.The variation of traits in fast-growing period was more significant.The height and basal diameter were significantly correlated to their increments in earlygrowing period(0.744,0.928),fast-growing period(0.965,0.804),and their daily mean increment in fastgrowing period(0.733,0.811).展开更多
基金Supported by National Scientific and Technological Project in Rural Areas in the "Twelfth Five Year" Plan(2012BAD21B03,2012BAD21B0304)~~
文摘[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to differentiate the degrees of drought stress based on changes in soil water content and leaf water potential and investigate variations in contents of osmotic regulation substances（free proline,soluble sugar and soluble protein） in leaves of five Catalpa bungei clones under different degrees of drought stresses. [Result] According to changes in soil water content and leaf water potential, the whole process of drought stress was divided into normal level（CK, with soil water content of 97.49% and leaf water potential of-0.54MPa）, light drought（LD with soil water content of 59.96% and leaf water potential of-1.28 MPa）, mediate drought（MD with soil water content of 34.19% and leaf water potential of-2.32 MPa） and severe drought（SD with soil water content of 14.52%and leaf water potential of-2.99 MPa）. The soil water content and leaf water potential of five Catalpa bungei clones reached the highest correlation in exponential fitting, with an average R2of 0.989 3（P0.001）. The free proline content in leaves of five Catalpa bungei clones increased rapidly with the increasing degree of drought stress（P 0.001）. To be specific, free proline contents of Catalpa bungei clones015-1 and 7080 were 34.39 and 33.41 times of the normal level under severe drought conditions, which reached an extremely significant level（P0.001）; the free proline content of Catalpa bungei clone 1-3 rapidly increased to（855.46±227.52） μg/g Fw under light drought conditions. The soluble protein content in leaves showed different variation trends. To be specific, the soluble protein content of Catalpa bungei clone 7080 was the lowest at various drought stages and reached（1.644 ±0.137）mg/g Fw under normal conditions; the soluble protein content of Catalpa bungei clone 1-3 was relatively high under normal conditions and was reduced rapidly under light drought conditions, showing different response patterns. [Conclusion] Osmotic regulation substances in leaves of five Catalpa bungei clones all have certain response to drought stress. Free proline is the most important osmotic regulation substance, followed by soluble protein, while soluble sugar makes no significant contribution. According to changes in content of osmotic regulation substances, Catalpa bungei clone 7080 has relatively high capacity and good drought resistance, while Catalpa bungei clone 1-3 has the rapidest response to drought stress.
文摘In order to study the growth traits of Catalpa bungei clones in various growth periods during the nursery stage so as to provide a theoretical basis for genetic improvement,the authors matched the height and diameter in nursery stage by Logistic equation.The results showed that the mean height of clones was 325.19 cm,with the range of 253.48-402.88 cm,the mean basal diameter of clones was 4.29 cm,with the range of 3.61-5.05 cm.The height increment could be divided into two stage,i.e.the early-growing period and the fast-growing period,while the basal diameter increment could be divided into three stage,i.e.the early-growing period,the fast-growing period and the late-growing period.The beginning of fast-growing period,the end of fast-growing period,the duration of fast-growing period,and the daily mean height increment in fast-growing period were May 26-July 2,September 11-October 15,72-128 days,and 1.70-2.88 cm,while that for basal diameter increment were May 9-June 5,August 23-October 3,95-138 days,and 0.021-0.032 cm.The variation of traits in fast-growing period was more significant.The height and basal diameter were significantly correlated to their increments in earlygrowing period(0.744,0.928),fast-growing period(0.965,0.804),and their daily mean increment in fastgrowing period(0.733,0.811).
