[ Objective] This study aimed to investigate the effects of 5-aminolevulinic acid （ALA） on the content of total flavonoids and relative expression levels of chalcoue sythase （CHS） and chalcone isomerase （CHI） ge...[ Objective] This study aimed to investigate the effects of 5-aminolevulinic acid （ALA） on the content of total flavonoids and relative expression levels of chalcoue sythase （CHS） and chalcone isomerase （CHI） genes in young apples to determine the appropriate ALA concentration and processing time. [Method] Before thinning, young apples were treated with 0 （ CK）, 100,200,300 and 400 mg/L ALA. At 12 d after ALA treatment, the content of total flavonoids in young apples was determined by ultraviolet spectrophotometry. The relative expression levels of CHS and CHI genes in young apples were determined by qPCR. [ Result ] When ALA concentration was 0 - 300 mg/L, the content of total flavonoids and relative expression levels of CHS and CHI genes in young apples were improved with the increase of ALA concentration. As ALA concentration rose to 400 rag/L, various indicators showed a downward trend. Moreover, the content of total flavouoids and relative expression levels of CHS and CHI genes in young apples treated with different concentrations of ALA were improved significantly, which reached the maximum at 9 d and declined since 12 d. [ Conclusion] Compared with CK, spraying young apples with 300 mg/L ALA at 6 -9 d before thinning was conducive to improving the content of flavanoids in thinned young apples.展开更多
Wireless sensor network(WSN)nodes exchange information via wireless signals,whose power can attenuate at different levels according to the propagation environment.The branches and leaves of young apple trees are much ...Wireless sensor network(WSN)nodes exchange information via wireless signals,whose power can attenuate at different levels according to the propagation environment.The branches and leaves of young apple trees are much sparser than that of adult apple trees.Propagation rules such as propagation distance and attenuation rate are the parameters necessary to know before applying a WSN to a young apple orchard.Field tests were performed,and propagation distance and packet loss rate(PLR)were computed and compared under the two cases:a young apple orchard in fruit period and an open space to find the effect of the apple trees on radio propagation.A model of antenna height and propagation distance was created to forecast the extra path loss caused by the young trees.Validation experiments were performed in a different young apple orchard,and the validation results showed that 70% of R^(2) were higher than 0.7,while the smallest being 0.65;80% RMSE were smaller than 5.The new model was also compared with some classical models such as Cost 235,FITU,ITU-R,and Weissberger model,and the new model was proved to be the best.展开更多
基金Supported by Earmarked Fund for Modern Agro-industry Technology Research System of China(GK661001)
文摘[ Objective] This study aimed to investigate the effects of 5-aminolevulinic acid （ALA） on the content of total flavonoids and relative expression levels of chalcoue sythase （CHS） and chalcone isomerase （CHI） genes in young apples to determine the appropriate ALA concentration and processing time. [Method] Before thinning, young apples were treated with 0 （ CK）, 100,200,300 and 400 mg/L ALA. At 12 d after ALA treatment, the content of total flavonoids in young apples was determined by ultraviolet spectrophotometry. The relative expression levels of CHS and CHI genes in young apples were determined by qPCR. [ Result ] When ALA concentration was 0 - 300 mg/L, the content of total flavonoids and relative expression levels of CHS and CHI genes in young apples were improved with the increase of ALA concentration. As ALA concentration rose to 400 rag/L, various indicators showed a downward trend. Moreover, the content of total flavouoids and relative expression levels of CHS and CHI genes in young apples treated with different concentrations of ALA were improved significantly, which reached the maximum at 9 d and declined since 12 d. [ Conclusion] Compared with CK, spraying young apples with 300 mg/L ALA at 6 -9 d before thinning was conducive to improving the content of flavanoids in thinned young apples.
基金financially supported by the National High Technology and Development Program of China(863):Model-based digital management platform for orchard and rape plants(2013AA102405).
文摘Wireless sensor network(WSN)nodes exchange information via wireless signals,whose power can attenuate at different levels according to the propagation environment.The branches and leaves of young apple trees are much sparser than that of adult apple trees.Propagation rules such as propagation distance and attenuation rate are the parameters necessary to know before applying a WSN to a young apple orchard.Field tests were performed,and propagation distance and packet loss rate(PLR)were computed and compared under the two cases:a young apple orchard in fruit period and an open space to find the effect of the apple trees on radio propagation.A model of antenna height and propagation distance was created to forecast the extra path loss caused by the young trees.Validation experiments were performed in a different young apple orchard,and the validation results showed that 70% of R^(2) were higher than 0.7,while the smallest being 0.65;80% RMSE were smaller than 5.The new model was also compared with some classical models such as Cost 235,FITU,ITU-R,and Weissberger model,and the new model was proved to be the best.
