Manual fruit thinning(MFT)in fruit trees has been previously shown to increase fruit size and enhance fruit quality,but the effect of MFT on Ponkan(Citrus reticulata Blanco)and the underlying mechanisms remain poorly ...Manual fruit thinning(MFT)in fruit trees has been previously shown to increase fruit size and enhance fruit quality,but the effect of MFT on Ponkan(Citrus reticulata Blanco)and the underlying mechanisms remain poorly understood.In this study,efforts were made to elucidate how MFT influences the fruit quality of Ponkan.The results showed that MFT substantially increased fruit size and elevated fruit total soluble solids in comparison with the fruit from the unthinned trees(used as control).Expression analyses demonstrated that m RNA abundance of three important sugar transporter genes,including CrSUT1,CrSTP1 and CrTMT1,was evidently elevated in the flesh of thinned fruit when compared with those of the control.In addition,MFT prominently up-regulated the transcript levels of various auxin and gibberellin(GA)biosynthesis and signaling genes,including CrYUC6,CrAUX/IAA,CrGA20ox1 and CrGA3ox1.Concurrently,the contents of endogenous IAA and GA3,measured at 90 d after fruit thinning,were notably elevated in the fruit from trees with the thinning treatment relative to the control,although no difference was detected in the two groups before the thinning manipulation.Taken together,these results indicate that manual fruit thinning could greatly improve fruit quality,which may be attributed to promoting fruit expansion due to the increased auxin levels and expediting sugar accumulation through the up-regulation of sugar transporter genes.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
Huanglongbing （HLB, or citrus greening） is the most destructive disease of citrus, which is associated with Candidatus Liberibacter asiaticus （Las）. Few management options are available, aside from preventive meas...Huanglongbing （HLB, or citrus greening） is the most destructive disease of citrus, which is associated with Candidatus Liberibacter asiaticus （Las）. Few management options are available, aside from preventive measures such as removing infected plants, planting disease-free seedlings, and managing the insect vector. In this study, we assessed the efficacy of thermotherapy against HLB under controlled greenhouse conditions. A total of 60 two-year-old, graft-infected Citrus reticulata Blanco plants were used. The plants were randomly divided into three groups （45℃, 48℃, and untreated control）, with five plants/replicate （rep） and four reps/treatment. The treated plants were placed in phytotrons for a 4-h treatment session, repeated once per week for three consecutive weeks. Disease remission was observed eight weeks post-treatment. Real-time PCR assays revealed that Las titers in HLB-affected seedlings were significantly reduced in both 45 and 48℃ treatments four weeks after treatment, with the exception of eight plants. In contrast, Las titers in the untreated control plants increased significantly during the same period, with a maximum increase of 28-fold. Except for seven plants, Las titers in the new flushes of treated plants decreased more than 90% eight weeks after treatment. Las titers in mature leaves of treated plants decreased 56 and 60% in average at 45 and 48℃, respectively, eight weeks after treatment. The HLB symptoms and Las titer of seedings were markedly alleviated eight weeks after treatment in both 45 and 48℃ treatments. Our results laid a good foundation for the further development of citrus free-disease seedling cultivation and Huanglongbing control in the field. The whole plants were replaced for scion or branch in previous as the research object in this study, and the expression of Huanglongbing symptoms combined with real-time polymerase chain reaction （PCR） were used to evaluate the effect of heat treatment in the greenhouse.展开更多
Gametophytic self-incompatibility （GSI） is controlled by a highly polymorphic locus called the S-locus, which is an important factor that can result in seedless fruit in Citrus. The S 1 self-incompatibility locus-li...Gametophytic self-incompatibility （GSI） is controlled by a highly polymorphic locus called the S-locus, which is an important factor that can result in seedless fruit in Citrus. The S 1 self-incompatibility locus-linked pollen 3.15 gene （S1-3.15） belongs to a type of S locus gene. The role of S1-3.15 in the SI reaction of Citrus has not yet been reported. In this study, full-length sequences of cDNA and DNA encoding the S1-3.15 gene, referred to as CrS1-3.15 , were isolated from ‘Wuzishatangju’ （Self-incompatibility, SI） and ‘Shatangju’ （Self-compatibility, SC） . The predicted amino acid sequences of CrS1-3.15 between ‘Wuzishatangju’ and ‘Shatangju’ differ by only three amino acids. Compared to ‘Wuzishatangju’, three bases were substituted in the genomic DNA of CrS1-3.15 from ‘Shatangju’. Southern blot results showed that one copy of CrS1-3.15 existed in the genomic DNA of both ‘Wuzishatangju’ and ‘Shatangju’. The expression level of the CrS1-3.15 gene in the ovaries of ‘Shatangju’ was approximately 60-fold higher than that in the ovaries of ‘Wuzishatangju’. When ‘Wuzishatangju’ was cross-pollinated, the expression of CrS1-3.15 was upregulated in the ovaries at 3d, and the highest expression levels were detected in the ovaries at 6d after cross-pollination of ‘Wuzishatangju’ × ‘Shatangju’. To obtain the CrS1-3.15 protein, the full-length cDNA of CrS1-3.15 genes from ‘Wuzishatangju’ and ‘Shatangju’ was successfully expressed in Pichia pastoris. Pollen germination frequency of ‘Wuzishatangju’ was inhibited significantly with increasing CrS1-3.15 protein concentrations from SI ‘Wuzishatangju’.展开更多
Fruits are regarded as the richest dietary sources of polyphenols,carotenoids,terpenoids,and limonoids,making them highly desired prospects for the functional food industry.Citrus waste that remains after fruit proces...Fruits are regarded as the richest dietary sources of polyphenols,carotenoids,terpenoids,and limonoids,making them highly desired prospects for the functional food industry.Citrus waste that remains after fruit processing is also regarded as a valuable source of value-added phytochemicals.A comprehensive analysis of mandarin composition as a determinant of fruit functional properties,health benefits,and valorization into useful products is represented together with the effect of different processes such as light,wax coating,auxin addition,ozone treatment,and ethylene degreening.Such reviewing evidence is an essential precondition for improving the selling market of mandarin and highlighting its waste valorization potential and its incorporation into useful products produced by pharmaceutical industries.In this study,the phytochemical and biological reports presented to emphasize the needed priority for agricultural techniques to provide a certain mandarin product or trait.In addition,the paper summarizes the optimum conditions applied for the updated extraction techniques for phenolic acids,flavonoids,and oils at a commercial scale from mandarin peels and to enhance its global marketing.A brief representation is given towards potential mandarin patents and the valorization of its bio-waste fruits into commercial products of added value.The review can guide researchers to produce future potentially marketed functional food enriched with mandarin extracts and/or bioactives.展开更多
Objective To study the chemical constituents from Pericarpium Citri Reticulatae （Citrus reticulata）. Methods The chemical constituents were isolated and purified by silica gel column, Sephadex LH-20, and ODS column ...Objective To study the chemical constituents from Pericarpium Citri Reticulatae （Citrus reticulata）. Methods The chemical constituents were isolated and purified by silica gel column, Sephadex LH-20, and ODS column chromatography. The structures were identified by spectral data. Results Nineteen compounds were isolated and identified as 4＇,5,6,7-tetramethoxyflavone （1）, 3,3＇,4＇,5,6,7,8-heptmethoxyflavone （2）, sinensetin （3）, 5-O-demethylnobiletin （4）, tangeretin （5）, nobiletin （6）, apigenin （7）, 5-O- desmethyltangeretin （8）, 5,7-dihydroxy-3,3＇,4＇,6-tetramethoxyflavone （9）, pachypodol （10）, 4＇,5,6,7-tetramethoxyflavanone （11）, 3＇,4＇,5,7,8-pentamethoxyflavanone （12）, agestricin C （13）, scoparone （14）, isoscopoletin （15）, hesperidin （16）, didymin （17）, methylhesperidine （18）, and naringin （19）. Conclusion Compounds 9-15 are obtained from this plant for the first time.展开更多
Oviposition preference and egg deposition site selection by the butterfly, Papilio polytes L. （Lepidoptera： Papilionidae） on four rutaceous host plants, Citrus aurantofolia （Christm.） Swing., Citrus hystrix DC., ...Oviposition preference and egg deposition site selection by the butterfly, Papilio polytes L. （Lepidoptera： Papilionidae） on four rutaceous host plants, Citrus aurantofolia （Christm.） Swing., Citrus hystrix DC., Citrus reticulata Blanco, and Murraya koenigii （L.） Sprengel, were assessed in field cages measuring 2 × 2 ×2 m. Simultaneous two-choice and four-choice oviposition tests of whole host plants were conducted. The mean total number of eggs laid per plant on C. reticulata in the two-choice test was significantly higher （P 〈 0.01） than those on C. aurantifolia, C. hystrix, andM. koenigii. Among the three other host plants, C. aurantifolia was preferred over C. hystrix, and M. koenigii （P 〈 0.01） and C. hystrix was preferred over M. koenigii （P 〈 0.01）. In the four-choice test, C. reticulata was highly preferred and significantly different from C. hystrix and M. koenigii. However, no oviposition preference was detected with C. aurantifolia. Among the various plant parts in the two- and four-choice tests, eggs on leaves of each plant were the highest, followed by numbers on stems, and negligible numbers on pots. These numbers on leaves of C. reticulata and C. aurantifolia were not significantly different （P 〉 0.05）, but differed significantly （P 〈 0.01） from those on leaves of C. hystrix and M. koenigii. The quantitative trend of egg-laying on stems was very similar to that observed for the leaves. Papilio polytes showed strong preference to lay eggs on the underside of leaves of all host plants than on the upper side or on the petiole. More eggs were laid on the upper side of each host plant than on its petiole. The four host plants in descending order of preference were C. reticulata 〉 C. aurantifolia 〉 C. hystrix 〉 M. koenigii. Although M. koenigii was the least preferred, it has the potential to serve as an alternative host plant for P. polytes which can be manipulated when necessary, to alleviate the infestation of this pest to the citrus industry.展开更多
基金supported by the Hubei Provincial Agriculture Research System,Chinathe Special Program for Technology Innovation of Hubei Province,China(2020BBA036)the Hubei Provincial Agricultural Science and Technology Innovation,China。
文摘Manual fruit thinning(MFT)in fruit trees has been previously shown to increase fruit size and enhance fruit quality,but the effect of MFT on Ponkan(Citrus reticulata Blanco)and the underlying mechanisms remain poorly understood.In this study,efforts were made to elucidate how MFT influences the fruit quality of Ponkan.The results showed that MFT substantially increased fruit size and elevated fruit total soluble solids in comparison with the fruit from the unthinned trees(used as control).Expression analyses demonstrated that m RNA abundance of three important sugar transporter genes,including CrSUT1,CrSTP1 and CrTMT1,was evidently elevated in the flesh of thinned fruit when compared with those of the control.In addition,MFT prominently up-regulated the transcript levels of various auxin and gibberellin(GA)biosynthesis and signaling genes,including CrYUC6,CrAUX/IAA,CrGA20ox1 and CrGA3ox1.Concurrently,the contents of endogenous IAA and GA3,measured at 90 d after fruit thinning,were notably elevated in the fruit from trees with the thinning treatment relative to the control,although no difference was detected in the two groups before the thinning manipulation.Taken together,these results indicate that manual fruit thinning could greatly improve fruit quality,which may be attributed to promoting fruit expansion due to the increased auxin levels and expediting sugar accumulation through the up-regulation of sugar transporter genes.
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.
基金funded by the United States Department of Agriculture (USDA)-APHIS-PPQ-CPHST and North Carolina State University joint project (2012-0195-01)the Special Fund for Agro-Scientific Research in the Public Interest, China (201003067-05)
文摘Huanglongbing （HLB, or citrus greening） is the most destructive disease of citrus, which is associated with Candidatus Liberibacter asiaticus （Las）. Few management options are available, aside from preventive measures such as removing infected plants, planting disease-free seedlings, and managing the insect vector. In this study, we assessed the efficacy of thermotherapy against HLB under controlled greenhouse conditions. A total of 60 two-year-old, graft-infected Citrus reticulata Blanco plants were used. The plants were randomly divided into three groups （45℃, 48℃, and untreated control）, with five plants/replicate （rep） and four reps/treatment. The treated plants were placed in phytotrons for a 4-h treatment session, repeated once per week for three consecutive weeks. Disease remission was observed eight weeks post-treatment. Real-time PCR assays revealed that Las titers in HLB-affected seedlings were significantly reduced in both 45 and 48℃ treatments four weeks after treatment, with the exception of eight plants. In contrast, Las titers in the untreated control plants increased significantly during the same period, with a maximum increase of 28-fold. Except for seven plants, Las titers in the new flushes of treated plants decreased more than 90% eight weeks after treatment. Las titers in mature leaves of treated plants decreased 56 and 60% in average at 45 and 48℃, respectively, eight weeks after treatment. The HLB symptoms and Las titer of seedings were markedly alleviated eight weeks after treatment in both 45 and 48℃ treatments. Our results laid a good foundation for the further development of citrus free-disease seedling cultivation and Huanglongbing control in the field. The whole plants were replaced for scion or branch in previous as the research object in this study, and the expression of Huanglongbing symptoms combined with real-time polymerase chain reaction （PCR） were used to evaluate the effect of heat treatment in the greenhouse.
基金supported by the National Natural Science Foundation of China(31000899)the Research Fund for the Doctoral Program of Higher Education of China(20104404120015 and 20114404110018)+4 种基金the Guangdong Province Science Foundation of China(06025843)the Science and Technology Planning Project of Guangzhou(2010r1-C771)the open foundation of the State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources,South China Agricultural University(KSL-CUSAb-2012-09)the Key Laboratory of Innovation and Utilization for Germplasm Resources in Horticultural Crops in Southern China of Guangdong Higher Education Institutes,South China Agricultural University(No.KBL11008)the "211" Construction Fund for Key Subjects of College of Horticulture,South China Agricultural University
文摘Gametophytic self-incompatibility （GSI） is controlled by a highly polymorphic locus called the S-locus, which is an important factor that can result in seedless fruit in Citrus. The S 1 self-incompatibility locus-linked pollen 3.15 gene （S1-3.15） belongs to a type of S locus gene. The role of S1-3.15 in the SI reaction of Citrus has not yet been reported. In this study, full-length sequences of cDNA and DNA encoding the S1-3.15 gene, referred to as CrS1-3.15 , were isolated from ‘Wuzishatangju’ （Self-incompatibility, SI） and ‘Shatangju’ （Self-compatibility, SC） . The predicted amino acid sequences of CrS1-3.15 between ‘Wuzishatangju’ and ‘Shatangju’ differ by only three amino acids. Compared to ‘Wuzishatangju’, three bases were substituted in the genomic DNA of CrS1-3.15 from ‘Shatangju’. Southern blot results showed that one copy of CrS1-3.15 existed in the genomic DNA of both ‘Wuzishatangju’ and ‘Shatangju’. The expression level of the CrS1-3.15 gene in the ovaries of ‘Shatangju’ was approximately 60-fold higher than that in the ovaries of ‘Wuzishatangju’. When ‘Wuzishatangju’ was cross-pollinated, the expression of CrS1-3.15 was upregulated in the ovaries at 3d, and the highest expression levels were detected in the ovaries at 6d after cross-pollination of ‘Wuzishatangju’ × ‘Shatangju’. To obtain the CrS1-3.15 protein, the full-length cDNA of CrS1-3.15 genes from ‘Wuzishatangju’ and ‘Shatangju’ was successfully expressed in Pichia pastoris. Pollen germination frequency of ‘Wuzishatangju’ was inhibited significantly with increasing CrS1-3.15 protein concentrations from SI ‘Wuzishatangju’.
文摘Fruits are regarded as the richest dietary sources of polyphenols,carotenoids,terpenoids,and limonoids,making them highly desired prospects for the functional food industry.Citrus waste that remains after fruit processing is also regarded as a valuable source of value-added phytochemicals.A comprehensive analysis of mandarin composition as a determinant of fruit functional properties,health benefits,and valorization into useful products is represented together with the effect of different processes such as light,wax coating,auxin addition,ozone treatment,and ethylene degreening.Such reviewing evidence is an essential precondition for improving the selling market of mandarin and highlighting its waste valorization potential and its incorporation into useful products produced by pharmaceutical industries.In this study,the phytochemical and biological reports presented to emphasize the needed priority for agricultural techniques to provide a certain mandarin product or trait.In addition,the paper summarizes the optimum conditions applied for the updated extraction techniques for phenolic acids,flavonoids,and oils at a commercial scale from mandarin peels and to enhance its global marketing.A brief representation is given towards potential mandarin patents and the valorization of its bio-waste fruits into commercial products of added value.The review can guide researchers to produce future potentially marketed functional food enriched with mandarin extracts and/or bioactives.
基金Project of Guangdong Natural Science Foundation(No.2015A030310284,No.2015A030312001)Project of Chinese Public Welfare Industry Special(Agriculture)Research(No.201503142-03)Project of Agricultural Research in Guangdong Province(No.2015A020209065)
文摘Objective To study the chemical constituents from Pericarpium Citri Reticulatae （Citrus reticulata）. Methods The chemical constituents were isolated and purified by silica gel column, Sephadex LH-20, and ODS column chromatography. The structures were identified by spectral data. Results Nineteen compounds were isolated and identified as 4＇,5,6,7-tetramethoxyflavone （1）, 3,3＇,4＇,5,6,7,8-heptmethoxyflavone （2）, sinensetin （3）, 5-O-demethylnobiletin （4）, tangeretin （5）, nobiletin （6）, apigenin （7）, 5-O- desmethyltangeretin （8）, 5,7-dihydroxy-3,3＇,4＇,6-tetramethoxyflavone （9）, pachypodol （10）, 4＇,5,6,7-tetramethoxyflavanone （11）, 3＇,4＇,5,7,8-pentamethoxyflavanone （12）, agestricin C （13）, scoparone （14）, isoscopoletin （15）, hesperidin （16）, didymin （17）, methylhesperidine （18）, and naringin （19）. Conclusion Compounds 9-15 are obtained from this plant for the first time.
文摘Oviposition preference and egg deposition site selection by the butterfly, Papilio polytes L. （Lepidoptera： Papilionidae） on four rutaceous host plants, Citrus aurantofolia （Christm.） Swing., Citrus hystrix DC., Citrus reticulata Blanco, and Murraya koenigii （L.） Sprengel, were assessed in field cages measuring 2 × 2 ×2 m. Simultaneous two-choice and four-choice oviposition tests of whole host plants were conducted. The mean total number of eggs laid per plant on C. reticulata in the two-choice test was significantly higher （P 〈 0.01） than those on C. aurantifolia, C. hystrix, andM. koenigii. Among the three other host plants, C. aurantifolia was preferred over C. hystrix, and M. koenigii （P 〈 0.01） and C. hystrix was preferred over M. koenigii （P 〈 0.01）. In the four-choice test, C. reticulata was highly preferred and significantly different from C. hystrix and M. koenigii. However, no oviposition preference was detected with C. aurantifolia. Among the various plant parts in the two- and four-choice tests, eggs on leaves of each plant were the highest, followed by numbers on stems, and negligible numbers on pots. These numbers on leaves of C. reticulata and C. aurantifolia were not significantly different （P 〉 0.05）, but differed significantly （P 〈 0.01） from those on leaves of C. hystrix and M. koenigii. The quantitative trend of egg-laying on stems was very similar to that observed for the leaves. Papilio polytes showed strong preference to lay eggs on the underside of leaves of all host plants than on the upper side or on the petiole. More eggs were laid on the upper side of each host plant than on its petiole. The four host plants in descending order of preference were C. reticulata 〉 C. aurantifolia 〉 C. hystrix 〉 M. koenigii. Although M. koenigii was the least preferred, it has the potential to serve as an alternative host plant for P. polytes which can be manipulated when necessary, to alleviate the infestation of this pest to the citrus industry.
