Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect no...Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect normal fruit growth and reduce fruit quality and yield.We took five-year-old Ruixue’(Qinfu 1×Pink Lady;CNA20151469.1) fruits as test materials,and the ambient temperature during fruit development was monitored.The results showed that during the fruit-growing season,especially during the rapid growth stage (July to August),the maximum daily temperature exceeded 30℃ and lasted for more than 40 days.To determine the effects of high temperature stress on the apple fruit resistance,we treated expanding,veraison,and maturity-period fruits at different temperatures.It was found that the fruits of the expanding period showed strong resistance to high temperature stress,whereas during veraison and maturity,fruit resistance to high temperature stress decreased,and the fruit peel browning phenotype appeared.Meanwhile,the content of malonaldehyde (MDA),hydrogen peroxide (H_(2)O_(2)),and superoxide anion (O._(2)^(-)) in the peel gradually increased with increasing temperature.The content of total phenols,flavanol,and flavonoids in the peel decreased substantially at 45℃.Moreover,it was found that polyphenol oxidase gene (MdPPO1) was most sensitive to high temperature stress in apple.Furthermore,transient and stable MdPPO1 overexpression significantly promoted peel browning.The transgenic materials were more sensitive to high temperatures,and browning was more severe compared to non-genetically modified organism (WT).Stable MdPPO1 knockout calli obtained via clustered regularly interspersed short palindromic repeats (CRISPR/Cas9) gene knockout technology reduced the browning phenotype,and the resultant fruits were not sensitive to the effects of high temperature stress.Thus,MdPPO1 expression may be a key factor of high temperature-related changes observed in the browning phenotype that provides a scientific theoretical basis for the selection of high temperature-resistant varieties and apple cultivation and management in the future.展开更多
Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning ...Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning of vegetation remain scarce.In this study,we utilized the normalized difference vegetation index(NDVI)as an indicator of vegetation to investigate the trends of vegetation greening and browning(monotonic,interruption,and reversal)through the breaks for the additive season and trend(BFAST)method across China’s drylands from 1982 to 2022.It also reveals the impacts of ecological restoration programs(ERPs)and climate change on these vegetation trends.We find that the vegetation displays an obvious pattern of east-greening and west-browning in China’s drylands.Greening trends mainly exhibits monotonic greening(29.8%)and greening with setback(36.8%),whereas browning shows a greening to browning reversal(19.2%).The increase rate of greening to browning reversal is 0.0342/yr,which is apparently greater than that of greening with setback,0.0078/yr.This research highlights that,under the background of widespread vegetation greening,vegetation browning is pro-gressively increasing due to the effects of climate change.Furthermore,the ERPs have significantly increased vegetation coverage,with the increase rate in 2000-2022 being twice as much as that of 1982-1999 in reveg-etation regions.Vegetation browning in southwestern Qingzang Plateau is primarily driven by adverse climatic factors and anthropogenic disturbances,which offset the efforts of ERPs.展开更多
Peel browning of pomegranate fruit is the key problem during storage. The mechanism of it during storage in relation to the technology of the browning control was studied in this paper. The effects of storage temperat...Peel browning of pomegranate fruit is the key problem during storage. The mechanism of it during storage in relation to the technology of the browning control was studied in this paper. The effects of storage temperature, gas component and pH value on peel browning of sweet pomegranate fruit in Lintong, Shaanxi Province, China, were investigated. Change in tannin content was measured and the relationship between the activities of ascorbic acid oxidase (AAO), polypenoloxidase (PPO), peroxidase (POD), catalase (CAT) and peel browning was analysed. The results showed tannin was the basic substance of pomegranate peel browning. The activities of the browning index of peel were correlated positively with AAO, PPO and POD, correlated negatively with CAT activity. Application of intermittent warming for 24 h at (15 ± 0.5)℃ every 5 days for pomegranate fruit storage under the conditions of pH 4.0, (5.0± 0.5)℃ and 5.0% CO2 + 8.0% O2 + 87.0% N2 gas component could delay browning, with the browning index being 0.15 after 120 days of storage. Enzymatic tannin denaturation was the main cause that led to peel browning of pomegranate fruit during storage. The browning control of pomegranate fruit peel was effective using intermittent warming storage with suitable pH, temperature and gas component.展开更多
Huangguan pear (Pyrus bretschneideri Rehd cv. Huangguan) is a pear cultivar that rapidly developed in China. However, rapid postharvest browning appearing in fruit peel and core during storage and shelf life pose a ch...Huangguan pear (Pyrus bretschneideri Rehd cv. Huangguan) is a pear cultivar that rapidly developed in China. However, rapid postharvest browning appearing in fruit peel and core during storage and shelf life pose a challenge for their marketing. The potential for low temperature conditioning (LTC) treatment to inhibit peel browning and improve quality of Huangguan pears in storage and shelf life was investigated. Pears were treated at 8℃ - 9℃ for 1, 3, 6 and 9 d, respectively, physiological indexes, including peel and core browning, core breakdown, malondialdehyde (MDA) content and ethanol content were determined and quality in storage period and shelf life was evaluated in this paper. LTC treatment alleviated peel browning and core browning either in storage or shelf life remarkably;it also delayed the decline of firmness, total soluble solids and titratable acidity in storage to some extent, inhibited ethanol and MDA content both in storage and shelf life effectively and maintained juiciness and crispness of pear fruit in shelf life. These results showed that LTC can serve as an important tool for the regulation of Huangguan pears external and internal quality in storage and shelf life with economic benefits and LTC treatment for 6 d was the optimum condition in the present study.展开更多
Objective: To determine the exposure of wild brown hares [Lepus europaeus(L. europaeus), pallas] to Anaplasma phagocytophilum(A. phagocytophilum), Borrelia burgdorferi(B. burgdorferi) sensu lato, Encephalitozoon cunic...Objective: To determine the exposure of wild brown hares [Lepus europaeus(L. europaeus), pallas] to Anaplasma phagocytophilum(A. phagocytophilum), Borrelia burgdorferi(B. burgdorferi) sensu lato, Encephalitozoon cuniculi(E. cuniculi), Leishmania sp., Neospora caninum(N. caninum) and Toxoplasma gondii(T. gondii). Methods: Two hundred twentytwo blood serum samples of wild brown hares captured in protected areas of the province of Pisa(Central Italy) were tested to detect antibodies against the reported pathogens. Results: Thirty one(14.0%) animals resulted positive for at least one tested agent, with antibody titres ranging from 1:20 to 1:320. In particular, 13(5.8%) samples were positive to B. burgdorferis.l., 11(4.9%) to N. caninum, 3(1.3%) to T. gondii, 2(0.9%) to A. phagocytophilum and 2(0.9%) to Leishmania sp. No samples scored positive to E. cuniculi. Four animals(14.8%) resulted coinfected with 2 different pathogens. Conclusion: The obtained results showed that B. burgdorferi s.l. N. caninum, T. gondii, A. phagocytophilum and Leishmania sp circulate in wild brown hares in Central Italy, suggesting a possible role of L. europaeus as reservoir of these pathogens. The obtained results showed that autochthonous wild brown hares living in Central Italy have been exposed to several pathogens circulating in this area, suggesting a possible role of L. europaeus as reservoir.展开更多
Purpose: Brown’s Syndrome (BS) is a restrictive strabismus characterized by a limitation of elevation in adduction. Several etiologies have been described, usually involving the superior oblique muscle. Spontaneous i...Purpose: Brown’s Syndrome (BS) is a restrictive strabismus characterized by a limitation of elevation in adduction. Several etiologies have been described, usually involving the superior oblique muscle. Spontaneous improvement has been reported in several studies, so surgery is reserved for a minority of cases. Our purpose is to review the characteristics, natural history and treatment of this pathology and present the experience of the Instituto de Oftalmologia Dr. Gama Pinto (IOGP). Methods: A consecutive retrospective series of BS patients seen at the Strabismus Department of IOGP between 1983 and 2014 was reviewed. All patients with complete clinical data were included in this study. The epidemiologic characteristics, clinical features, treatment, and clinical progression were reviewed. Results: Thirty-nine cases were selected, with a mean age at first diagnosis of 6.5 years. Of the thirty-nine cases, 6 were iatrogenic and the remainder idiopathic. Thirty-six cases were followed for a mean period of 6.1 years. Surgical intervention for BS was performed in 11 patients, using different approaches. Of these, 9 cases were considered successful. The remaining 25 cases were kept under observation without surgery, of which 17 showed spontaneous improvement and the other 7 remained unchanged. Conclusions: The surgical success rate was 82%, which demonstrates the good efficacy of the surgery despite the complexity and variety of pathophysiological mechanisms of the syndrome. In the patients kept under observation there was spontaneous improvement in 68%, confirming that a conservative approach seems to be adequate in most cases.展开更多
基金supported by China Agriculture Research System of MOF and MARA (Grant No.CARS-27)the Fundamental Research Funds for the Central Universities (Grant No.2452020033)Shaanxi Engineering Research Center of Apple。
文摘Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect normal fruit growth and reduce fruit quality and yield.We took five-year-old Ruixue’(Qinfu 1×Pink Lady;CNA20151469.1) fruits as test materials,and the ambient temperature during fruit development was monitored.The results showed that during the fruit-growing season,especially during the rapid growth stage (July to August),the maximum daily temperature exceeded 30℃ and lasted for more than 40 days.To determine the effects of high temperature stress on the apple fruit resistance,we treated expanding,veraison,and maturity-period fruits at different temperatures.It was found that the fruits of the expanding period showed strong resistance to high temperature stress,whereas during veraison and maturity,fruit resistance to high temperature stress decreased,and the fruit peel browning phenotype appeared.Meanwhile,the content of malonaldehyde (MDA),hydrogen peroxide (H_(2)O_(2)),and superoxide anion (O._(2)^(-)) in the peel gradually increased with increasing temperature.The content of total phenols,flavanol,and flavonoids in the peel decreased substantially at 45℃.Moreover,it was found that polyphenol oxidase gene (MdPPO1) was most sensitive to high temperature stress in apple.Furthermore,transient and stable MdPPO1 overexpression significantly promoted peel browning.The transgenic materials were more sensitive to high temperatures,and browning was more severe compared to non-genetically modified organism (WT).Stable MdPPO1 knockout calli obtained via clustered regularly interspersed short palindromic repeats (CRISPR/Cas9) gene knockout technology reduced the browning phenotype,and the resultant fruits were not sensitive to the effects of high temperature stress.Thus,MdPPO1 expression may be a key factor of high temperature-related changes observed in the browning phenotype that provides a scientific theoretical basis for the selection of high temperature-resistant varieties and apple cultivation and management in the future.
基金supported by the National Natural Science Foundation of China(Grants No.41991231,42041004,and 41888101)the China University Research Talents Recruitment Program(111 project,Grant No.B13045).
文摘Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning of vegetation remain scarce.In this study,we utilized the normalized difference vegetation index(NDVI)as an indicator of vegetation to investigate the trends of vegetation greening and browning(monotonic,interruption,and reversal)through the breaks for the additive season and trend(BFAST)method across China’s drylands from 1982 to 2022.It also reveals the impacts of ecological restoration programs(ERPs)and climate change on these vegetation trends.We find that the vegetation displays an obvious pattern of east-greening and west-browning in China’s drylands.Greening trends mainly exhibits monotonic greening(29.8%)and greening with setback(36.8%),whereas browning shows a greening to browning reversal(19.2%).The increase rate of greening to browning reversal is 0.0342/yr,which is apparently greater than that of greening with setback,0.0078/yr.This research highlights that,under the background of widespread vegetation greening,vegetation browning is pro-gressively increasing due to the effects of climate change.Furthermore,the ERPs have significantly increased vegetation coverage,with the increase rate in 2000-2022 being twice as much as that of 1982-1999 in reveg-etation regions.Vegetation browning in southwestern Qingzang Plateau is primarily driven by adverse climatic factors and anthropogenic disturbances,which offset the efforts of ERPs.
基金the Natural Science Foundation of Shaanxi Province,China(2004C109)Key Technology R&D Program of Shaanxi Province,China(2003K02-G6)Agricultural Science and Technology Development of Xi'an City,China(NG200313).
文摘Peel browning of pomegranate fruit is the key problem during storage. The mechanism of it during storage in relation to the technology of the browning control was studied in this paper. The effects of storage temperature, gas component and pH value on peel browning of sweet pomegranate fruit in Lintong, Shaanxi Province, China, were investigated. Change in tannin content was measured and the relationship between the activities of ascorbic acid oxidase (AAO), polypenoloxidase (PPO), peroxidase (POD), catalase (CAT) and peel browning was analysed. The results showed tannin was the basic substance of pomegranate peel browning. The activities of the browning index of peel were correlated positively with AAO, PPO and POD, correlated negatively with CAT activity. Application of intermittent warming for 24 h at (15 ± 0.5)℃ every 5 days for pomegranate fruit storage under the conditions of pH 4.0, (5.0± 0.5)℃ and 5.0% CO2 + 8.0% O2 + 87.0% N2 gas component could delay browning, with the browning index being 0.15 after 120 days of storage. Enzymatic tannin denaturation was the main cause that led to peel browning of pomegranate fruit during storage. The browning control of pomegranate fruit peel was effective using intermittent warming storage with suitable pH, temperature and gas component.
文摘Huangguan pear (Pyrus bretschneideri Rehd cv. Huangguan) is a pear cultivar that rapidly developed in China. However, rapid postharvest browning appearing in fruit peel and core during storage and shelf life pose a challenge for their marketing. The potential for low temperature conditioning (LTC) treatment to inhibit peel browning and improve quality of Huangguan pears in storage and shelf life was investigated. Pears were treated at 8℃ - 9℃ for 1, 3, 6 and 9 d, respectively, physiological indexes, including peel and core browning, core breakdown, malondialdehyde (MDA) content and ethanol content were determined and quality in storage period and shelf life was evaluated in this paper. LTC treatment alleviated peel browning and core browning either in storage or shelf life remarkably;it also delayed the decline of firmness, total soluble solids and titratable acidity in storage to some extent, inhibited ethanol and MDA content both in storage and shelf life effectively and maintained juiciness and crispness of pear fruit in shelf life. These results showed that LTC can serve as an important tool for the regulation of Huangguan pears external and internal quality in storage and shelf life with economic benefits and LTC treatment for 6 d was the optimum condition in the present study.
文摘Objective: To determine the exposure of wild brown hares [Lepus europaeus(L. europaeus), pallas] to Anaplasma phagocytophilum(A. phagocytophilum), Borrelia burgdorferi(B. burgdorferi) sensu lato, Encephalitozoon cuniculi(E. cuniculi), Leishmania sp., Neospora caninum(N. caninum) and Toxoplasma gondii(T. gondii). Methods: Two hundred twentytwo blood serum samples of wild brown hares captured in protected areas of the province of Pisa(Central Italy) were tested to detect antibodies against the reported pathogens. Results: Thirty one(14.0%) animals resulted positive for at least one tested agent, with antibody titres ranging from 1:20 to 1:320. In particular, 13(5.8%) samples were positive to B. burgdorferis.l., 11(4.9%) to N. caninum, 3(1.3%) to T. gondii, 2(0.9%) to A. phagocytophilum and 2(0.9%) to Leishmania sp. No samples scored positive to E. cuniculi. Four animals(14.8%) resulted coinfected with 2 different pathogens. Conclusion: The obtained results showed that B. burgdorferi s.l. N. caninum, T. gondii, A. phagocytophilum and Leishmania sp circulate in wild brown hares in Central Italy, suggesting a possible role of L. europaeus as reservoir of these pathogens. The obtained results showed that autochthonous wild brown hares living in Central Italy have been exposed to several pathogens circulating in this area, suggesting a possible role of L. europaeus as reservoir.
文摘Purpose: Brown’s Syndrome (BS) is a restrictive strabismus characterized by a limitation of elevation in adduction. Several etiologies have been described, usually involving the superior oblique muscle. Spontaneous improvement has been reported in several studies, so surgery is reserved for a minority of cases. Our purpose is to review the characteristics, natural history and treatment of this pathology and present the experience of the Instituto de Oftalmologia Dr. Gama Pinto (IOGP). Methods: A consecutive retrospective series of BS patients seen at the Strabismus Department of IOGP between 1983 and 2014 was reviewed. All patients with complete clinical data were included in this study. The epidemiologic characteristics, clinical features, treatment, and clinical progression were reviewed. Results: Thirty-nine cases were selected, with a mean age at first diagnosis of 6.5 years. Of the thirty-nine cases, 6 were iatrogenic and the remainder idiopathic. Thirty-six cases were followed for a mean period of 6.1 years. Surgical intervention for BS was performed in 11 patients, using different approaches. Of these, 9 cases were considered successful. The remaining 25 cases were kept under observation without surgery, of which 17 showed spontaneous improvement and the other 7 remained unchanged. Conclusions: The surgical success rate was 82%, which demonstrates the good efficacy of the surgery despite the complexity and variety of pathophysiological mechanisms of the syndrome. In the patients kept under observation there was spontaneous improvement in 68%, confirming that a conservative approach seems to be adequate in most cases.