Corolla opening is essential for the propagation of unisexual flowering plants,meanwhile commodity fruits with opening corolla have higher commodity value in cucumber fresh food market.Until now,there is little resear...Corolla opening is essential for the propagation of unisexual flowering plants,meanwhile commodity fruits with opening corolla have higher commodity value in cucumber fresh food market.Until now,there is little research on the mechanism of corolla opening in cucumber.In a previous paper,we identified a unique cucumber(Cucumis sativus)line(‘6457’)that possesses super ovaries and shows delayed corolla opening when nutrient supplies are abundant.We also previously showed that the expression of CsIPT1b(isopentenyl transferase)and CsUGT85A2(cytokinin glycosyltransferase)is correlated with the delayed opening of the female corolla.Here,we investigated the mechanism of delayed female corolla opening in cucumber by conducting transgenic experiments,hormone assays,and yeast one-hybrid assays.CsIPT1b and CsUGT85A2 positively and negatively regulated delayed female corolla opening,respectively.In CsIPT1b-overexpressing plants and CsUGT85A2 knockout plants,the content of the trans-zeatin riboside,trans-zeatin,and N6-isopentenyladenosine was increased.Overall,our findings indicate that CsIPT1b and CsUGT85A2 were important regulators of the timing of female corolla opening.These genes could thus be targets to cucumber molecular breeding of fruit with flowers remaining on the tip.展开更多
Since its 2018 invasion of eastern Asia,the fall armyworm Spodoptera frugiperda(Lepidoptera:Noctuidae)has become a key pest in local maize production.Though pesticides have been widely used to mitigate the initial S.f...Since its 2018 invasion of eastern Asia,the fall armyworm Spodoptera frugiperda(Lepidoptera:Noctuidae)has become a key pest in local maize production.Though pesticides have been widely used to mitigate the initial S.frugiperda attack,biological control is receiving ample attention as a desirable,environmentally-sound alternative to chemical control.Hoverflies(Diptera:Syrphidae)are abundant natural enemies in Chinese maize fields and have been observed to consume S.frugiperda larvae.In this study,we use laboratory assays to study the two-way interaction between immature stages of S.frugiperda and the endemic syrphid Eupeodes corollae.To mimic natural conditions,assays were performed in the presence of fresh maize leaves.Those 2 nd or 3 rd instar larvae of E.corollae preyed on 1 st and 2 nd instar S.frugiperda larvae with a Holling type III response,consuming a respective theoretical maximum of 43.48 and 83.33 larvae over a 24-h period.Conversely,once S.frugiperda larvae reached 3 rd instar,they exhibited aggressive behavior and equally preyed on syrphid larvae with a Holling type III response.Those 5 th and 6 th instar larvae of S.frugiperda consumed a respective 16.39-19.23,6.02-19.61 and 6.76-8.26 of 1 st,2 nd and 3 rd instar E.corollae larvae per day.Though our results await field-level validation,S.frugiperda agonistic(i.e.,defensive)and consumptive behavior towards resident natural enemies such as E.corollae possibly degrades biotic resistance and raises its invasion potential.Our findings shine new light on the interaction between lepidopteran herbivores and their natural enemies,and can help advance the development of conservation biological control and other integrated pest management(IPM)strategies against S.frugiperda in China and abroad.展开更多
‘Corollas and spines’ is an important trait for fresh market cucumber. In a unique cucumber line, ‘6457’, the super ovary is much larger and corolla opening is delayed by 4–5 days, thus the resulting fruit has a ...‘Corollas and spines’ is an important trait for fresh market cucumber. In a unique cucumber line, ‘6457’, the super ovary is much larger and corolla opening is delayed by 4–5 days, thus the resulting fruit has a flower that remains on the tip,which has a high commodity value. In this study, to better understand the molecular basis of corolla opening, mRNA and miRNA transcriptome analyses were performed during corolla development of the super and normal ovaries. A total of 234 differentially expressed miRNAs(DEMs) and 291 differentially expressed target genes(DE-target genes) were identified from four developmental stages, and the greatest number of DEMs was found at the yellow bud stage. Thirty of the DE-target genes were regulated by more than five DEMs, among which, CsHD-Zip was regulated by 28 DEMs,followed by DD2X(18). In addition, the expression patterns of miRNA_104, miRNA_157, miRNA_349, miRNA_242, and miRNA_98 were similar during corolla development, and they shared the same target gene, CsCuRX. Moreover, several critical candidate DEMs and DE-target genes were characterized and profiled by a qRT-PCR experiment. Three of the miRNAs, miRNA_157-CsCuRX, miRNA_411-CsGH3.6, and miRNA_161/297/257-CsHD-Zip, might be responsible for corolla opening in the cucumber super ovary. This integrated study on the transcriptional and post-transcriptional profiles can provide insights into the molecular regulatory mechanism underlying corolla opening in the cucumber.展开更多
Toyota's liquid hydrogen-fueled GR Corolla finally made its racing debut in the ENEOS Super Taikyu Series 2023 Round 2 NAPAC Fuji SUPER TEC 24 Hours Race,which was held from May 26 to 28,2023.It is the world's...Toyota's liquid hydrogen-fueled GR Corolla finally made its racing debut in the ENEOS Super Taikyu Series 2023 Round 2 NAPAC Fuji SUPER TEC 24 Hours Race,which was held from May 26 to 28,2023.It is the world's first car to race with liquid hydrogen as its power source.展开更多
The evolution of long corolla tubes has been hypothesized to be driven by long-tongued pollinators.Corolla tubes in Pedicularis species can be longer than 10 cm which may function as flower stalks to increase visual a...The evolution of long corolla tubes has been hypothesized to be driven by long-tongued pollinators.Corolla tubes in Pedicularis species can be longer than 10 cm which may function as flower stalks to increase visual attractiveness to pollinators because these species provide no nectar and are pollinated by bumblebees. The corolla tube length was manipulated（shorter or longer） in two Pedicularis species in field to examine whether longer tubes are more attractive to pollinators and produce more seeds than short tubes. Our results did not support the pollinator attraction hypothesis, leaving the evolution of long tubes in Pedicularis remains mysterious.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31772327)S&T Program of Hebei(Grant No.21326309D).
文摘Corolla opening is essential for the propagation of unisexual flowering plants,meanwhile commodity fruits with opening corolla have higher commodity value in cucumber fresh food market.Until now,there is little research on the mechanism of corolla opening in cucumber.In a previous paper,we identified a unique cucumber(Cucumis sativus)line(‘6457’)that possesses super ovaries and shows delayed corolla opening when nutrient supplies are abundant.We also previously showed that the expression of CsIPT1b(isopentenyl transferase)and CsUGT85A2(cytokinin glycosyltransferase)is correlated with the delayed opening of the female corolla.Here,we investigated the mechanism of delayed female corolla opening in cucumber by conducting transgenic experiments,hormone assays,and yeast one-hybrid assays.CsIPT1b and CsUGT85A2 positively and negatively regulated delayed female corolla opening,respectively.In CsIPT1b-overexpressing plants and CsUGT85A2 knockout plants,the content of the trans-zeatin riboside,trans-zeatin,and N6-isopentenyladenosine was increased.Overall,our findings indicate that CsIPT1b and CsUGT85A2 were important regulators of the timing of female corolla opening.These genes could thus be targets to cucumber molecular breeding of fruit with flowers remaining on the tip.
基金supported by the earmarked fund for China Agriculture Research System(CARS-15-19)。
文摘Since its 2018 invasion of eastern Asia,the fall armyworm Spodoptera frugiperda(Lepidoptera:Noctuidae)has become a key pest in local maize production.Though pesticides have been widely used to mitigate the initial S.frugiperda attack,biological control is receiving ample attention as a desirable,environmentally-sound alternative to chemical control.Hoverflies(Diptera:Syrphidae)are abundant natural enemies in Chinese maize fields and have been observed to consume S.frugiperda larvae.In this study,we use laboratory assays to study the two-way interaction between immature stages of S.frugiperda and the endemic syrphid Eupeodes corollae.To mimic natural conditions,assays were performed in the presence of fresh maize leaves.Those 2 nd or 3 rd instar larvae of E.corollae preyed on 1 st and 2 nd instar S.frugiperda larvae with a Holling type III response,consuming a respective theoretical maximum of 43.48 and 83.33 larvae over a 24-h period.Conversely,once S.frugiperda larvae reached 3 rd instar,they exhibited aggressive behavior and equally preyed on syrphid larvae with a Holling type III response.Those 5 th and 6 th instar larvae of S.frugiperda consumed a respective 16.39-19.23,6.02-19.61 and 6.76-8.26 of 1 st,2 nd and 3 rd instar E.corollae larvae per day.Though our results await field-level validation,S.frugiperda agonistic(i.e.,defensive)and consumptive behavior towards resident natural enemies such as E.corollae possibly degrades biotic resistance and raises its invasion potential.Our findings shine new light on the interaction between lepidopteran herbivores and their natural enemies,and can help advance the development of conservation biological control and other integrated pest management(IPM)strategies against S.frugiperda in China and abroad.
基金supported by the National Natural Science Foundation of China(31772327 and 31801877)the Hebei Vegetable Innovation Projects of Modern Agricultural Industry Technology System,China(HBCT2018030209)。
文摘‘Corollas and spines’ is an important trait for fresh market cucumber. In a unique cucumber line, ‘6457’, the super ovary is much larger and corolla opening is delayed by 4–5 days, thus the resulting fruit has a flower that remains on the tip,which has a high commodity value. In this study, to better understand the molecular basis of corolla opening, mRNA and miRNA transcriptome analyses were performed during corolla development of the super and normal ovaries. A total of 234 differentially expressed miRNAs(DEMs) and 291 differentially expressed target genes(DE-target genes) were identified from four developmental stages, and the greatest number of DEMs was found at the yellow bud stage. Thirty of the DE-target genes were regulated by more than five DEMs, among which, CsHD-Zip was regulated by 28 DEMs,followed by DD2X(18). In addition, the expression patterns of miRNA_104, miRNA_157, miRNA_349, miRNA_242, and miRNA_98 were similar during corolla development, and they shared the same target gene, CsCuRX. Moreover, several critical candidate DEMs and DE-target genes were characterized and profiled by a qRT-PCR experiment. Three of the miRNAs, miRNA_157-CsCuRX, miRNA_411-CsGH3.6, and miRNA_161/297/257-CsHD-Zip, might be responsible for corolla opening in the cucumber super ovary. This integrated study on the transcriptional and post-transcriptional profiles can provide insights into the molecular regulatory mechanism underlying corolla opening in the cucumber.
文摘Toyota's liquid hydrogen-fueled GR Corolla finally made its racing debut in the ENEOS Super Taikyu Series 2023 Round 2 NAPAC Fuji SUPER TEC 24 Hours Race,which was held from May 26 to 28,2023.It is the world's first car to race with liquid hydrogen as its power source.
基金National Science Foundation of China (No. 31270281) to SQH supported this work
文摘The evolution of long corolla tubes has been hypothesized to be driven by long-tongued pollinators.Corolla tubes in Pedicularis species can be longer than 10 cm which may function as flower stalks to increase visual attractiveness to pollinators because these species provide no nectar and are pollinated by bumblebees. The corolla tube length was manipulated（shorter or longer） in two Pedicularis species in field to examine whether longer tubes are more attractive to pollinators and produce more seeds than short tubes. Our results did not support the pollinator attraction hypothesis, leaving the evolution of long tubes in Pedicularis remains mysterious.
