[Objectives]This study was conducted to investigate the synergized preservation effect of different concentrations of prochloraz and chitosan on citrus Gonggan,so as to prolong the sales period of Gonggan.[Methods]&qu...[Objectives]This study was conducted to investigate the synergized preservation effect of different concentrations of prochloraz and chitosan on citrus Gonggan,so as to prolong the sales period of Gonggan.[Methods]"Zhongshan Gonggan" was used as a material.The Gonggan fruit was soaked with prochloraz (250,300 and 350 mg/L) and then coated with different concentrations of chitosan (1.0% and 1.5%),respectively.The good fruit rate,weight loss rate and titratable acid (TA),reducing sugar,total soluble solids (TSS) and Vc contents were used as evaluation indexes to investigate the preservation effect of Gonggan during cold storage.[Results]The treatment of prochloraz plus chitosan can significantly prolong the shelf life of Gonggan as it can inhibit the decline of good fruit rate,reduce the weight loss rate,and slow down the degradation and loss of titratable acid,reducing sugar,soluble solids and Vc.The 350 mg/L prochloraz+1.0% chitosan treatment was superior to other treatments.[Conclusions]This study provides a theoretical basis for better prolonging the storage period of Gonggan.展开更多
[Objective]This paper was to identify the pathogen of leaf brown-spot on‘gonggan’mandarin(Citrus reticulate var.gonggan)in Zhaoqing,Guangdong Province.[Method]The pathogen was determined based on sequence analysis o...[Objective]This paper was to identify the pathogen of leaf brown-spot on‘gonggan’mandarin(Citrus reticulate var.gonggan)in Zhaoqing,Guangdong Province.[Method]The pathogen was determined based on sequence analysis of ITS,endoPG,tef1,gapdh,Alt a1,rpb2 and opa10-2 genes;the morphological characteristics were recorded on PDA and PCA;and its pathogenicity on excised and intact host leaves of citrus‘gonggan’was tested.[Result]A detailed description of Alternaria gaisen was obtained based on morphological,molecular and pathogenic characterization,which was the causal agent of brown-spot disease on leaves of‘gonggan’mandarin orchard trees in Zhaoqing,Guangdong,China.[Conclusion]This study provides a scientific basis for the effective control of leaf brown-spot on‘gonggan’mandarin.展开更多
‘Gonggan’( Citrus reticulata) is a famous,high-quality and special citrus cultivar in the Xijiang River valley,Guangdong Province. However,it easily suffers from postharvest diseases,and thus is not tolerant to stor...‘Gonggan’( Citrus reticulata) is a famous,high-quality and special citrus cultivar in the Xijiang River valley,Guangdong Province. However,it easily suffers from postharvest diseases,and thus is not tolerant to storage. Based on the preliminary test results,prochloraz-manganese chloride complex was selected as the disinfectant,and prepared into different concentrations for carrying out preservation test by dipping fruits. The fruit weight loss,soluble solids content and decay rate were analyzed,and the application security and sensory evaluation for fruit freshness and flavor were observed. The results showed that dipping fruits with prochloraz-manganese chloride complex solution had significant preservation effect on‘Gonggan’fruits in postharvest storage; the suitable concentration was 2. 0-3. 0 g/L,and the decay rates of fruits stored at room temperature for 30,60 and 90 d were below 5%,10% and 15%,respectively. Plate inoculation test further revealed that the pathogen of‘Gonggan’was sensitive to prochloraz-manganese chloride complex,and the concentration of 1. 0 g/L was enough to produce significant antimicrobial effect. Other technical links related to postharvest preservation of‘Gonggan’with prochloraz-manganese chloride complex were discussed.展开更多
[Objectives]This study was conducted to understand the infection characteristics of Penicillium on‘Gonggan’mandarin(Citrus reticulata)and its effects on postharvest storage quality.[Methods]Nine inoculation treatmen...[Objectives]This study was conducted to understand the infection characteristics of Penicillium on‘Gonggan’mandarin(Citrus reticulata)and its effects on postharvest storage quality.[Methods]Nine inoculation treatments were designed and tested for the three identified Penicillium species,namely:three single inoculation experiments,four compound inoculation experiments,and two controls without inoculation.After treatment,the fruit was put into plastic film fresh-keeping bags and stored at a natural room temperature.The determined and analyzed indexes included fruit disease incidence,disease index,disease symptoms,disease spot expansion speed and weight loss rate,soluble solid content and organic acid content in different inoculation treatments.[Results]All‘Gonggan’fruit inoculated with Penicillium were diseased 2 d after inoculation,and completely rotted 14 d later.Of the three Penicillium species isolated and identified,Penicillium digitorum and its combinations were the most harmful to‘Gonggan’fruit.The hazard of Penicillium italicum was equal to or even weaker than that of Penicillium expansum.Eventually,P.digitorum dominated when coexisting on the same fruit.Different species of Penicillium obviously showed competition and antagonism in the process of growth and infection,especially for P.digitorum which was stronger,but other two species of Penicillium also had obvious self-protection ability.Low-temperature storage played a crucial role in the preservation of‘Gonggan’fruit,because it could significantly inhibit Penicillium infestation,and suppress fruit weight loss and the reduction of the contents of soluble solids and organic acids.[Conclusions]The infection characteristics and interaction relationship of Penicillium in the postharvest storage of‘Gonggan’fruit were revealed.展开更多
[Objectives]To investigate the effects and mechanism of fruit immersion treatment with salicylic acid(SA),calcium chloride(CaCl_(2))solutions at different concentrations or their combinations on post-harvest preservat...[Objectives]To investigate the effects and mechanism of fruit immersion treatment with salicylic acid(SA),calcium chloride(CaCl_(2))solutions at different concentrations or their combinations on post-harvest preservation of Gonggan Mandarin(Citrus reticulata)fruit.[Methods]13 experiments(2 storage temperatures,3 control treatments,3 concentrations of SA solution,4 concentrations of CaCl_(2) solution and 3 combinations of SA+CaCl_(2) solution for fruit immersion treatment)were conducted for 90 d.Gonggan fruit weight loss rate,rotting rate,disease index,disease type,soluble solids and organic acids content,and the differences in the activity of six enzymes(APX,PPO,CHI,CAT,SOD,PAL)related to fruit disease resistance were detected regularly.[Results]With the increase of storage days,the weight loss rate,rotting rate and disease index increased,the content of soluble solids and organic acids decreased,the activity of APX,PPO,CHI and SOD increased,and the activity of CAT and PAL decreased.However,the increase or decrease of fruit loss at low temperature was the smallest,and the increase or decrease of fruit at natural room temperature was the largest.Gonggan fruit cleaning before storage is an effective preservation and fresh-keeping technology,but its preservation and fresh-keeping effect is far less than that of fruit immersion by SA,CaCl_(2) and SA+CaCl_(2) compound solution.The effect of fruit immersion by SA solution was greater than that of fruit immersion by CaCl_(2) solution;the best concentration of SA alone was 6.0 mmol/L,which was not significantly different from 3.0 mmol/L,but the effect of 9.0 mmol/L decreased;the best concentration of CaCl_(2) alone was 6.0 mmol/L,which was significantly better than 3.0 and 9.0 mmol/L;the optimal concentration combination of SA+CaCl_(2) compound solution for fruit immersion treatment was 6.0 mmol/L SA+3.0 mmol/L CaCl_(2).[Conclusions]The fruit immersion by SA,CaCl_(2) and their compound solutions induced the increase of activity of six enzymes related to disease resistance in Gonggan fruit,and PPO and CHI were judged to be two key enzymes based on response intensity.展开更多
借助动力学、热力学等方法,研究不同热风干燥温度下贡柑片在干燥过程中的干燥规律、动力学模型、水分迁移、热力学参数等,解析超声微波协同预处理对热风干燥贡柑片干燥效率的影响。结果表明:贡柑片的干燥过程遵循Two term exponential模...借助动力学、热力学等方法,研究不同热风干燥温度下贡柑片在干燥过程中的干燥规律、动力学模型、水分迁移、热力学参数等,解析超声微波协同预处理对热风干燥贡柑片干燥效率的影响。结果表明:贡柑片的干燥过程遵循Two term exponential模型,干燥速率与干燥温度有关,且当干燥温度为80℃时,干燥速率最快;超声微波协同预处理可有效缩短贡柑片的干燥时间(缩短了0.5~1.5 h),并显著降低其水分扩散的活化能(降低了1.620 kJ/mol);同一热风干燥温度下,超声微波协同预处理组的ΔH^(≠)、ΔS^(≠)和ΔG^(≠)均低于对照组;超声微波协同预处理可提高贡柑片的水分扩散有效系数(4.333×10^(-7)~8.967×10^(-7)),使其表面形成更多孔道。因此,超声微波协同预处理可有效提高贡柑片的热风干燥效率。展开更多
基金Supported by Natural Science Foundation of Guangxi(2017GXNSFAA198082)Hezhou Scientific Research and Technology Development Program of Guangxi(HKG1541005)
文摘[Objectives]This study was conducted to investigate the synergized preservation effect of different concentrations of prochloraz and chitosan on citrus Gonggan,so as to prolong the sales period of Gonggan.[Methods]"Zhongshan Gonggan" was used as a material.The Gonggan fruit was soaked with prochloraz (250,300 and 350 mg/L) and then coated with different concentrations of chitosan (1.0% and 1.5%),respectively.The good fruit rate,weight loss rate and titratable acid (TA),reducing sugar,total soluble solids (TSS) and Vc contents were used as evaluation indexes to investigate the preservation effect of Gonggan during cold storage.[Results]The treatment of prochloraz plus chitosan can significantly prolong the shelf life of Gonggan as it can inhibit the decline of good fruit rate,reduce the weight loss rate,and slow down the degradation and loss of titratable acid,reducing sugar,soluble solids and Vc.The 350 mg/L prochloraz+1.0% chitosan treatment was superior to other treatments.[Conclusions]This study provides a theoretical basis for better prolonging the storage period of Gonggan.
基金Guangxi Key Laboratory of Biology for Crop Disease and Insect Pests(2019-KF-01).
文摘[Objective]This paper was to identify the pathogen of leaf brown-spot on‘gonggan’mandarin(Citrus reticulate var.gonggan)in Zhaoqing,Guangdong Province.[Method]The pathogen was determined based on sequence analysis of ITS,endoPG,tef1,gapdh,Alt a1,rpb2 and opa10-2 genes;the morphological characteristics were recorded on PDA and PCA;and its pathogenicity on excised and intact host leaves of citrus‘gonggan’was tested.[Result]A detailed description of Alternaria gaisen was obtained based on morphological,molecular and pathogenic characterization,which was the causal agent of brown-spot disease on leaves of‘gonggan’mandarin orchard trees in Zhaoqing,Guangdong,China.[Conclusion]This study provides a scientific basis for the effective control of leaf brown-spot on‘gonggan’mandarin.
基金Supported by Science and Technology Project of Guangdong Province(2014A020208143)Natural Science Foundation of Guangdong Province(S2013010015195)+1 种基金Science and Technology Innovation Project of Guangdong Department of Education(2013KJCX0192)Special Fund for the Introduction of Talents in Colleges and Universities of Guangdong Province(2010)
文摘‘Gonggan’( Citrus reticulata) is a famous,high-quality and special citrus cultivar in the Xijiang River valley,Guangdong Province. However,it easily suffers from postharvest diseases,and thus is not tolerant to storage. Based on the preliminary test results,prochloraz-manganese chloride complex was selected as the disinfectant,and prepared into different concentrations for carrying out preservation test by dipping fruits. The fruit weight loss,soluble solids content and decay rate were analyzed,and the application security and sensory evaluation for fruit freshness and flavor were observed. The results showed that dipping fruits with prochloraz-manganese chloride complex solution had significant preservation effect on‘Gonggan’fruits in postharvest storage; the suitable concentration was 2. 0-3. 0 g/L,and the decay rates of fruits stored at room temperature for 30,60 and 90 d were below 5%,10% and 15%,respectively. Plate inoculation test further revealed that the pathogen of‘Gonggan’was sensitive to prochloraz-manganese chloride complex,and the concentration of 1. 0 g/L was enough to produce significant antimicrobial effect. Other technical links related to postharvest preservation of‘Gonggan’with prochloraz-manganese chloride complex were discussed.
基金Supported by Guangdong Science and Technology Planning Project(2014A020208143)。
文摘[Objectives]This study was conducted to understand the infection characteristics of Penicillium on‘Gonggan’mandarin(Citrus reticulata)and its effects on postharvest storage quality.[Methods]Nine inoculation treatments were designed and tested for the three identified Penicillium species,namely:three single inoculation experiments,four compound inoculation experiments,and two controls without inoculation.After treatment,the fruit was put into plastic film fresh-keeping bags and stored at a natural room temperature.The determined and analyzed indexes included fruit disease incidence,disease index,disease symptoms,disease spot expansion speed and weight loss rate,soluble solid content and organic acid content in different inoculation treatments.[Results]All‘Gonggan’fruit inoculated with Penicillium were diseased 2 d after inoculation,and completely rotted 14 d later.Of the three Penicillium species isolated and identified,Penicillium digitorum and its combinations were the most harmful to‘Gonggan’fruit.The hazard of Penicillium italicum was equal to or even weaker than that of Penicillium expansum.Eventually,P.digitorum dominated when coexisting on the same fruit.Different species of Penicillium obviously showed competition and antagonism in the process of growth and infection,especially for P.digitorum which was stronger,but other two species of Penicillium also had obvious self-protection ability.Low-temperature storage played a crucial role in the preservation of‘Gonggan’fruit,because it could significantly inhibit Penicillium infestation,and suppress fruit weight loss and the reduction of the contents of soluble solids and organic acids.[Conclusions]The infection characteristics and interaction relationship of Penicillium in the postharvest storage of‘Gonggan’fruit were revealed.
基金Supported by Guangdong Science and Technology Plan Project(2014A020208143)。
文摘[Objectives]To investigate the effects and mechanism of fruit immersion treatment with salicylic acid(SA),calcium chloride(CaCl_(2))solutions at different concentrations or their combinations on post-harvest preservation of Gonggan Mandarin(Citrus reticulata)fruit.[Methods]13 experiments(2 storage temperatures,3 control treatments,3 concentrations of SA solution,4 concentrations of CaCl_(2) solution and 3 combinations of SA+CaCl_(2) solution for fruit immersion treatment)were conducted for 90 d.Gonggan fruit weight loss rate,rotting rate,disease index,disease type,soluble solids and organic acids content,and the differences in the activity of six enzymes(APX,PPO,CHI,CAT,SOD,PAL)related to fruit disease resistance were detected regularly.[Results]With the increase of storage days,the weight loss rate,rotting rate and disease index increased,the content of soluble solids and organic acids decreased,the activity of APX,PPO,CHI and SOD increased,and the activity of CAT and PAL decreased.However,the increase or decrease of fruit loss at low temperature was the smallest,and the increase or decrease of fruit at natural room temperature was the largest.Gonggan fruit cleaning before storage is an effective preservation and fresh-keeping technology,but its preservation and fresh-keeping effect is far less than that of fruit immersion by SA,CaCl_(2) and SA+CaCl_(2) compound solution.The effect of fruit immersion by SA solution was greater than that of fruit immersion by CaCl_(2) solution;the best concentration of SA alone was 6.0 mmol/L,which was not significantly different from 3.0 mmol/L,but the effect of 9.0 mmol/L decreased;the best concentration of CaCl_(2) alone was 6.0 mmol/L,which was significantly better than 3.0 and 9.0 mmol/L;the optimal concentration combination of SA+CaCl_(2) compound solution for fruit immersion treatment was 6.0 mmol/L SA+3.0 mmol/L CaCl_(2).[Conclusions]The fruit immersion by SA,CaCl_(2) and their compound solutions induced the increase of activity of six enzymes related to disease resistance in Gonggan fruit,and PPO and CHI were judged to be two key enzymes based on response intensity.
文摘借助动力学、热力学等方法,研究不同热风干燥温度下贡柑片在干燥过程中的干燥规律、动力学模型、水分迁移、热力学参数等,解析超声微波协同预处理对热风干燥贡柑片干燥效率的影响。结果表明:贡柑片的干燥过程遵循Two term exponential模型,干燥速率与干燥温度有关,且当干燥温度为80℃时,干燥速率最快;超声微波协同预处理可有效缩短贡柑片的干燥时间(缩短了0.5~1.5 h),并显著降低其水分扩散的活化能(降低了1.620 kJ/mol);同一热风干燥温度下,超声微波协同预处理组的ΔH^(≠)、ΔS^(≠)和ΔG^(≠)均低于对照组;超声微波协同预处理可提高贡柑片的水分扩散有效系数(4.333×10^(-7)~8.967×10^(-7)),使其表面形成更多孔道。因此,超声微波协同预处理可有效提高贡柑片的热风干燥效率。