The degree of surface wrinkles on a dried jujube fruit(Ziziphus jujuba Mill.)is an important quality grading criterion.The aim of this research was to propose an image processing method based on the watershed segmenta...The degree of surface wrinkles on a dried jujube fruit(Ziziphus jujuba Mill.)is an important quality grading criterion.The aim of this research was to propose an image processing method based on the watershed segmentation to extract the wrinkle features of jujube fruits.Original images of jujube fruit taken under cyan light were transformed into grayscale images.The noise in these images was then removed by morphological reconstruction.The H-minima extended transformation was used to label the foreground of jujube fruit images after reconstruction,and the labeled foreground regions were segmented by a distance transform-based watershed algorithm.Then,the grayscale images were filtered with a local range filter.The segmentation function was obtained using the minima imposition method.Finally,a watershed segmentation was used to extract the wrinkle features of jujube fruits.Experiments on 304 images of jujube fruit showed that the accuracy of wrinkle-based grading obtained by the algorithm was 92.11%,which proved that this method could be used to classify jujube wrinkles.展开更多
In order to explore the effects of arginine(Arg)treatment on postharvest rot of jujube caused by Alternaria alternata(A.alternata),winter jujube was treated with different concentrations of Arg(0,20,200,and 1000μmol/...In order to explore the effects of arginine(Arg)treatment on postharvest rot of jujube caused by Alternaria alternata(A.alternata),winter jujube was treated with different concentrations of Arg(0,20,200,and 1000μmol/L).Results showed that Arg treatment substantially inhibited the expansion of lesion diameter,and jujubes treated with 200μmol/L Arg had the smallest lesion diameter.In vitro experiments demonstrated that Arg could not inhibit spore germination and mycelial growth of A.alternata.Further experimental results showed that Arg treatment reduced the production rate of O_(2)^(-) and H_(2)O_(2) content and improved the activities of superoxide dismutase,catalase,peroxidase,and ascorbate peroxidase in comparison with the control;Arg treatment enhanced the activities of chitinase andβ-1,3-glucanase.Furthermore,Arg treatment significantly increased the activity of phenylalamine ammonia lyase and the contents of flavonoids,phenolics,and lignin.Results indicated that,although Arg could not directly inhibit the growth of pathogenic fungi as a fungicide,it can induce resistance to Alternaria rot by maintaining the balance of reactive oxygen species,increasing the activities of pathogenesis-related protein,and promoting the phenylpropane metabolism in jujube fruit tissue.Therefore,Arg treatment can be a novel measure for inducing the resistance of jujube to postharvest Alternaria rot.展开更多
基金supported by National Key Research Program(2016YFD0701501)Beijing Higher Education Young Elite Teacher Project(YETP0318).
文摘The degree of surface wrinkles on a dried jujube fruit(Ziziphus jujuba Mill.)is an important quality grading criterion.The aim of this research was to propose an image processing method based on the watershed segmentation to extract the wrinkle features of jujube fruits.Original images of jujube fruit taken under cyan light were transformed into grayscale images.The noise in these images was then removed by morphological reconstruction.The H-minima extended transformation was used to label the foreground of jujube fruit images after reconstruction,and the labeled foreground regions were segmented by a distance transform-based watershed algorithm.Then,the grayscale images were filtered with a local range filter.The segmentation function was obtained using the minima imposition method.Finally,a watershed segmentation was used to extract the wrinkle features of jujube fruits.Experiments on 304 images of jujube fruit showed that the accuracy of wrinkle-based grading obtained by the algorithm was 92.11%,which proved that this method could be used to classify jujube wrinkles.
基金the National Natural Science Foundation of China(No.31671905)the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(2018),China.
文摘In order to explore the effects of arginine(Arg)treatment on postharvest rot of jujube caused by Alternaria alternata(A.alternata),winter jujube was treated with different concentrations of Arg(0,20,200,and 1000μmol/L).Results showed that Arg treatment substantially inhibited the expansion of lesion diameter,and jujubes treated with 200μmol/L Arg had the smallest lesion diameter.In vitro experiments demonstrated that Arg could not inhibit spore germination and mycelial growth of A.alternata.Further experimental results showed that Arg treatment reduced the production rate of O_(2)^(-) and H_(2)O_(2) content and improved the activities of superoxide dismutase,catalase,peroxidase,and ascorbate peroxidase in comparison with the control;Arg treatment enhanced the activities of chitinase andβ-1,3-glucanase.Furthermore,Arg treatment significantly increased the activity of phenylalamine ammonia lyase and the contents of flavonoids,phenolics,and lignin.Results indicated that,although Arg could not directly inhibit the growth of pathogenic fungi as a fungicide,it can induce resistance to Alternaria rot by maintaining the balance of reactive oxygen species,increasing the activities of pathogenesis-related protein,and promoting the phenylpropane metabolism in jujube fruit tissue.Therefore,Arg treatment can be a novel measure for inducing the resistance of jujube to postharvest Alternaria rot.
