Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-...Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-PCR experiments is essential for the accurate quantification of gene expression.In this study,eight candidate reference genes were selected from our previously published RNA-seq data,and primers for each candidate reference gene were designed and evaluated.The Cq values of the candidate reference genes were calculated by RT-qPCR in 31 different loquat samples,including 12 subgroups of developing or abiotic-stressed tissues.Different combinations of stable reference genes were screened according to a comprehensive rank,which was synthesized from the results of four algorithms,including the geNorm,NormFinder,BestKeeper andΔCt methods.The screened reference genes were verified by normalizing EjLGA1 in each subgroup.The obtained suitable combinations of reference genes for accurate normalization were GAPDH,EF1αand ACT for floral development;GAPDH,UBCE and ACT for fruit setting;EF1α,GAPDH and eIF2B for fruit ripening;ACT,EF1αand UBCE for leaves under heat stress;eIF2B,UBCE and EF1αfor leaves under freezing stress;EF1α,TUA and UBCE for leaves under salt stress;ACT,EF1αand eIF2B for immature pulp under freezing stress;ACT,UBCE and eIF2B for immature seeds under freezing stress;EF1α,eIF2B and UBCE for both immature pulp and seeds under freezing stress;UBCE,TUB and TUA for red-fleshed fruits under cold-storage stress;eIF2B,RPS3 and TUB for white-fleshed fruits under coldstorage stress;and eIF2B,UBCE and RPS3 for both red-and white-fleshed fruits under cold-storage stress.This study obtained different combinations of stable reference genes for accurate normalization in twelve subgroups of developing or abiotic-stressed tissues in loquat.To our knowledge,this is the first report to obtain stable reference genes for normalizing gene expression of abiotic-stressed tissues in E.japonica.The use of the three most stable reference genes could increase the reliability of future quantification experiments.展开更多
The objective of this research was investigated the effect of polyphenol oxidase microwave treatment on phenolic composition, antioxidant activity and microstructure of loquat fruit. Phenolic profile of methanolic ext...The objective of this research was investigated the effect of polyphenol oxidase microwave treatment on phenolic composition, antioxidant activity and microstructure of loquat fruit. Phenolic profile of methanolic extracts prepared from fresh, and microwave-treated samples were analyzed. Antioxidant activity was also evaluated by 2,2’-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS?+) and 1,1-diphenyl-2-picrylhydrazyl (DPPH+) methods. In addition, polyphenol oxidase inactivation was carried out using a response surface methodology to establish the optimal conditions of treatment. The phenolic content of fresh mesocarp was 311 ± 0.60 mg gallic acid equivalents (GAE)/100g dry weight (DW) and that of microwave-treated mesocarp was 1230 ± 0.36 mg GAE/100g DW. Total phenolic content of water/ methanol extract significantly increases after microwave treatment rather than methanolic extract of fresh loquat. Five glycoside phenolics were identified by HPLC-DAD-MS as 3-caffeoylquinic acid, 3-p-coumaroylquinic acid, 5-caffeoylquinic acid and quercetin-3-O-sambubioside. Methanolic extract of microwave-treated mesocarp showed higher antioxidant activity than that of fresh mesocarp. Thus, polyphenol oxidase inactivation by microwave energy preserved the integrity of phenolic compounds as well as antioxidant activity in mesocarp extracts prepared from loquat fruit. It was also noted that phenolics were more abundant in the microwaved samples than in the fresh samples.展开更多
The purpose of this study was to investigate the effects of various presowing treatments on the germinability(final germination percentage)and germination rate of loquat seeds in order to increase seedling production ...The purpose of this study was to investigate the effects of various presowing treatments on the germinability(final germination percentage)and germination rate of loquat seeds in order to increase seedling production in nurseries(applied research)as well as provide answers for important physiological issues related to loquat seeds and their seed coat(basic research).Three experiments were carried out with various pre-sowing treatments.These treatments included full or partial removal of seed coat(perisperm),partial cutting of cotyledons as well as moist chilling at 5℃ for 13 days and/or soaking the seeds in water or 250 ppm gibberellic acid(GA_(3))solution for 24 h.According to the results,cotyledons excision resulted in delayed germination,regardless of the presence or absence of the seed coat in comparison with the decoated seeds that demonstrated the highest germination rate amongst them.In addition,even the partial excision of seed coats affected positively both the germinability and the germination rate,compared to the control-intact seeds.Furthermore,control-intact seeds had a higher germination percentage when exposed to moist chilling independently of the application or not of gibberellin;while the combination of gibberellin application and moist chilling improved both the percentage and the rate of germination of decoated seeds.In conclusion,the role of perisperm(seed coat)in the germination procedure of loquat seeds seems to be important,indicating the existence of seed coat-imposed dormancy on loquat seeds.Finally,the existence of a mild endogenous embryo-dormancy on loquat is also discussed.展开更多
The effect of La 3+ and Eu 3+ on the rooting of Eriobotrya japonica Lindl. plantlet in vitro was studied with adding La 3+ and Eu 3+ to the rooted medium. The rooting rate, the number of root and the lengt...The effect of La 3+ and Eu 3+ on the rooting of Eriobotrya japonica Lindl. plantlet in vitro was studied with adding La 3+ and Eu 3+ to the rooted medium. The rooting rate, the number of root and the length of root were studied after transplanting 20 d. The activity of peroxidase, nitrate reductase and fresh weight of roots were determined after transplanting 44 d. The results show that the optimum concentration range of La 3+ (1.0~3.0 μmol·L -1), Eu 3+ (2.0~3.0 μmol·L -1) in the rooted medium can increase the rooting rate and the fresh weight of roots, and promote the length of root and raise the activities of peroxidase and nitrate reductase significantly. La 3+ has more effect in improving the rooting rate, root length and the activities of peroxidase and less effect in promoting root fresh weight and the activities of nitrate reductase than Eu 3+.展开更多
A devastating trunk beetle has been found in Baisha loquat in Dongshan Town, Wuzhong District, Suzhou City in recent years. It is iden-tified as a new insect species, Cryphalus eriobotryae, belonging to Scolytinae, Cu...A devastating trunk beetle has been found in Baisha loquat in Dongshan Town, Wuzhong District, Suzhou City in recent years. It is iden-tified as a new insect species, Cryphalus eriobotryae, belonging to Scolytinae, Curculionidae, Coleoptera. So far, loquat is known as the unique host of C. eriobotryae, and trees of 20-30 years old or 3-4 years old are all attacked by the insect. Holes drilled by adults with the diameter of about0.8 mm and sores(ate by adults) with the diameter of 1 mm are found on bark and trunk of damaged trees. Three-dimensional channels in 3-4 layers are formed in cortex, which are filled with insect dung. The phloem turns black-brown in late stage, and loses transport function, resulting in plant death and a great impact on loquat production and industrial development. During the occurrence period of C. eriobotryae from April to November,the damaged trunks and branches should be sprayed with 48% chlorpyrifos EC or 5% imidacloprid EC 100 times dilution once every 10 d for con-tinuous 2-3 times, and various states of the insect could be killed. If the phloem is damaged in the early and middle stages and does not turn black and brown completely, the plant could grow new cortex to realize recovery.展开更多
Relationships between plant water status and gas exchange parameters at increasing levels of water stress were determined in Algerie loquats which grown in 50 I pots. Changes in soil water content and stem water poten...Relationships between plant water status and gas exchange parameters at increasing levels of water stress were determined in Algerie loquats which grown in 50 I pots. Changes in soil water content and stem water potential and their effects on stomatal conductance (Gs ) and net photosynthesis (Pn) rate were followed in control plants and in plants without irrigation until the latter reached near permanent wilting point and some leaf abscission took place. Then, the irrigation was restarted and the comparison repeated. Soil water content and stem water potential gradually diminished in response to drought reaching the minimum values of 0.9 mm and -5.0 MPa, respectively, 9 days after watering suspension. Compromised plant water status had drastic effects on Gs values that dropped by 97% in the last day of the drought period. Pn was diminished by 80% at the end of the drought period. The increasing levels of water stress did not cause a steady increase in leaf temperature in non-irrigated plants. Non-irrigated plants wilted and lost some leaves due to the severity of the water stress. However, all non-irrigated plants survived and reached similar Pn than control plants just a week after the irrigation was restarted, confirming drought tolerance of loquat and suggesting that photosynthesis machinery remained intact.展开更多
Loquat(Eriobotrya japonica Lindl.)is an evergreen fruit tree species of the Rosaceae,and its unique flowering time greatly hinders its production.To explore the artificial regulation of loquat flowering time,we remove...Loquat(Eriobotrya japonica Lindl.)is an evergreen fruit tree species of the Rosaceae,and its unique flowering time greatly hinders its production.To explore the artificial regulation of loquat flowering time,we removed the main inflorescence(by cutting it)to induce reflowering.For different loquat tree cultivars with different stages,the inflorescence was removed by cutting the main floral axis at two alternative positions:the upper or the lower position beneath the inflorescence,and it was found that the proportion of reflowering resulting from removing the upper position of the main floral axis of yellow-flesh loquat cultivars during the full-bloom stage was the highest.In addition,compared with those of the normal-growing panicles,the number of flower buds and branch axes of the reflowering panicles decreased significantly after cutting.Importantly,these newly produced inflorescences flowered 2–4 months later than normal-growing inflorescences did,effectively prolonging both the flowering and fruiting time.In addition,qRT-PCR results showed that EjFT1,EjFT2,EjAP1–1 and EjAP1–2 were highly expressed in the floral axis.These findings highlighted a new method for extending the production cycle of loquat and provided a reference for the flowering regulation of loquat and other economically important fruit tree species.展开更多
基金funded by the Natural Science Foundation of Fujian Province(2021J05240)Fujian Provincial Science and Technology Project(2021N5014,2022N5006)+1 种基金Research Project of Putian Science and Technology Bureau(2021ZP08,2021ZP09,2021ZP10,2021ZP11)Scientific Research Project of Putian University(2018064).
文摘Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-PCR experiments is essential for the accurate quantification of gene expression.In this study,eight candidate reference genes were selected from our previously published RNA-seq data,and primers for each candidate reference gene were designed and evaluated.The Cq values of the candidate reference genes were calculated by RT-qPCR in 31 different loquat samples,including 12 subgroups of developing or abiotic-stressed tissues.Different combinations of stable reference genes were screened according to a comprehensive rank,which was synthesized from the results of four algorithms,including the geNorm,NormFinder,BestKeeper andΔCt methods.The screened reference genes were verified by normalizing EjLGA1 in each subgroup.The obtained suitable combinations of reference genes for accurate normalization were GAPDH,EF1αand ACT for floral development;GAPDH,UBCE and ACT for fruit setting;EF1α,GAPDH and eIF2B for fruit ripening;ACT,EF1αand UBCE for leaves under heat stress;eIF2B,UBCE and EF1αfor leaves under freezing stress;EF1α,TUA and UBCE for leaves under salt stress;ACT,EF1αand eIF2B for immature pulp under freezing stress;ACT,UBCE and eIF2B for immature seeds under freezing stress;EF1α,eIF2B and UBCE for both immature pulp and seeds under freezing stress;UBCE,TUB and TUA for red-fleshed fruits under cold-storage stress;eIF2B,RPS3 and TUB for white-fleshed fruits under coldstorage stress;and eIF2B,UBCE and RPS3 for both red-and white-fleshed fruits under cold-storage stress.This study obtained different combinations of stable reference genes for accurate normalization in twelve subgroups of developing or abiotic-stressed tissues in loquat.To our knowledge,this is the first report to obtain stable reference genes for normalizing gene expression of abiotic-stressed tissues in E.japonica.The use of the three most stable reference genes could increase the reliability of future quantification experiments.
文摘The objective of this research was investigated the effect of polyphenol oxidase microwave treatment on phenolic composition, antioxidant activity and microstructure of loquat fruit. Phenolic profile of methanolic extracts prepared from fresh, and microwave-treated samples were analyzed. Antioxidant activity was also evaluated by 2,2’-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS?+) and 1,1-diphenyl-2-picrylhydrazyl (DPPH+) methods. In addition, polyphenol oxidase inactivation was carried out using a response surface methodology to establish the optimal conditions of treatment. The phenolic content of fresh mesocarp was 311 ± 0.60 mg gallic acid equivalents (GAE)/100g dry weight (DW) and that of microwave-treated mesocarp was 1230 ± 0.36 mg GAE/100g DW. Total phenolic content of water/ methanol extract significantly increases after microwave treatment rather than methanolic extract of fresh loquat. Five glycoside phenolics were identified by HPLC-DAD-MS as 3-caffeoylquinic acid, 3-p-coumaroylquinic acid, 5-caffeoylquinic acid and quercetin-3-O-sambubioside. Methanolic extract of microwave-treated mesocarp showed higher antioxidant activity than that of fresh mesocarp. Thus, polyphenol oxidase inactivation by microwave energy preserved the integrity of phenolic compounds as well as antioxidant activity in mesocarp extracts prepared from loquat fruit. It was also noted that phenolics were more abundant in the microwaved samples than in the fresh samples.
文摘The purpose of this study was to investigate the effects of various presowing treatments on the germinability(final germination percentage)and germination rate of loquat seeds in order to increase seedling production in nurseries(applied research)as well as provide answers for important physiological issues related to loquat seeds and their seed coat(basic research).Three experiments were carried out with various pre-sowing treatments.These treatments included full or partial removal of seed coat(perisperm),partial cutting of cotyledons as well as moist chilling at 5℃ for 13 days and/or soaking the seeds in water or 250 ppm gibberellic acid(GA_(3))solution for 24 h.According to the results,cotyledons excision resulted in delayed germination,regardless of the presence or absence of the seed coat in comparison with the decoated seeds that demonstrated the highest germination rate amongst them.In addition,even the partial excision of seed coats affected positively both the germinability and the germination rate,compared to the control-intact seeds.Furthermore,control-intact seeds had a higher germination percentage when exposed to moist chilling independently of the application or not of gibberellin;while the combination of gibberellin application and moist chilling improved both the percentage and the rate of germination of decoated seeds.In conclusion,the role of perisperm(seed coat)in the germination procedure of loquat seeds seems to be important,indicating the existence of seed coat-imposed dormancy on loquat seeds.Finally,the existence of a mild endogenous embryo-dormancy on loquat is also discussed.
文摘The effect of La 3+ and Eu 3+ on the rooting of Eriobotrya japonica Lindl. plantlet in vitro was studied with adding La 3+ and Eu 3+ to the rooted medium. The rooting rate, the number of root and the length of root were studied after transplanting 20 d. The activity of peroxidase, nitrate reductase and fresh weight of roots were determined after transplanting 44 d. The results show that the optimum concentration range of La 3+ (1.0~3.0 μmol·L -1), Eu 3+ (2.0~3.0 μmol·L -1) in the rooted medium can increase the rooting rate and the fresh weight of roots, and promote the length of root and raise the activities of peroxidase and nitrate reductase significantly. La 3+ has more effect in improving the rooting rate, root length and the activities of peroxidase and less effect in promoting root fresh weight and the activities of nitrate reductase than Eu 3+.
文摘A devastating trunk beetle has been found in Baisha loquat in Dongshan Town, Wuzhong District, Suzhou City in recent years. It is iden-tified as a new insect species, Cryphalus eriobotryae, belonging to Scolytinae, Curculionidae, Coleoptera. So far, loquat is known as the unique host of C. eriobotryae, and trees of 20-30 years old or 3-4 years old are all attacked by the insect. Holes drilled by adults with the diameter of about0.8 mm and sores(ate by adults) with the diameter of 1 mm are found on bark and trunk of damaged trees. Three-dimensional channels in 3-4 layers are formed in cortex, which are filled with insect dung. The phloem turns black-brown in late stage, and loses transport function, resulting in plant death and a great impact on loquat production and industrial development. During the occurrence period of C. eriobotryae from April to November,the damaged trunks and branches should be sprayed with 48% chlorpyrifos EC or 5% imidacloprid EC 100 times dilution once every 10 d for con-tinuous 2-3 times, and various states of the insect could be killed. If the phloem is damaged in the early and middle stages and does not turn black and brown completely, the plant could grow new cortex to realize recovery.
基金partially financed by the Junta de Andalucía with European Union(FEDER)funds(AGR-03183)
文摘Relationships between plant water status and gas exchange parameters at increasing levels of water stress were determined in Algerie loquats which grown in 50 I pots. Changes in soil water content and stem water potential and their effects on stomatal conductance (Gs ) and net photosynthesis (Pn) rate were followed in control plants and in plants without irrigation until the latter reached near permanent wilting point and some leaf abscission took place. Then, the irrigation was restarted and the comparison repeated. Soil water content and stem water potential gradually diminished in response to drought reaching the minimum values of 0.9 mm and -5.0 MPa, respectively, 9 days after watering suspension. Compromised plant water status had drastic effects on Gs values that dropped by 97% in the last day of the drought period. Pn was diminished by 80% at the end of the drought period. The increasing levels of water stress did not cause a steady increase in leaf temperature in non-irrigated plants. Non-irrigated plants wilted and lost some leaves due to the severity of the water stress. However, all non-irrigated plants survived and reached similar Pn than control plants just a week after the irrigation was restarted, confirming drought tolerance of loquat and suggesting that photosynthesis machinery remained intact.
基金supported by Shaoguan City Science and Technology Planning Project(Social Development Direction-Supporting Scientific Research Workers Project)(Grant No.200811094530739)the Key Realm R&D Program of Guang Dong Provide(Grant No.2018B020202011)+2 种基金Open Fund of Key laboratory of Loquat Germplasm Innovation and Utilization(Putian University)Fujian Province University(Grant No.2019005)Guangdong Province College Students’Innovative and Entrepreneurial Training Program(Grant No.S202010576014X)。
文摘Loquat(Eriobotrya japonica Lindl.)is an evergreen fruit tree species of the Rosaceae,and its unique flowering time greatly hinders its production.To explore the artificial regulation of loquat flowering time,we removed the main inflorescence(by cutting it)to induce reflowering.For different loquat tree cultivars with different stages,the inflorescence was removed by cutting the main floral axis at two alternative positions:the upper or the lower position beneath the inflorescence,and it was found that the proportion of reflowering resulting from removing the upper position of the main floral axis of yellow-flesh loquat cultivars during the full-bloom stage was the highest.In addition,compared with those of the normal-growing panicles,the number of flower buds and branch axes of the reflowering panicles decreased significantly after cutting.Importantly,these newly produced inflorescences flowered 2–4 months later than normal-growing inflorescences did,effectively prolonging both the flowering and fruiting time.In addition,qRT-PCR results showed that EjFT1,EjFT2,EjAP1–1 and EjAP1–2 were highly expressed in the floral axis.These findings highlighted a new method for extending the production cycle of loquat and provided a reference for the flowering regulation of loquat and other economically important fruit tree species.