Phytohormone abscisic acid (ABA) was critical for many plant growth and developmental processesincluding seed maturation, germination and response to environmental factors. With the purpose to detectthe possible ABA r...Phytohormone abscisic acid (ABA) was critical for many plant growth and developmental processesincluding seed maturation, germination and response to environmental factors. With the purpose to detectthe possible ABA related signal transduction pathways, we tried to isolate ABA-regulated genes throughcDNA macroarray technology using ABA-treated rice seedling as materials (under treatment for 2, 4, 8 and12 h). Of 6144 cDNA clones tested, 37 differential clones showing induction or suppression for at least onetime, were isolated. Of them 30 and 7 were up- or down-regulated respectively. Sequence analyses revealedthat the putative encoded proteins were involved in different possible processes, including transcription,metabolism and resistance, photosynthesis, signal transduction, and seed maturation. 6 cDNA clones werefound to encode proteins with unknown functions. Regulation by ABA of 7 selected clones relating to signaltransduction or metabolism was confirmed by reverse transcription PCR. In addition, some clones werefurther shown to be regulated by other plant growth regulators including auxin and brassinosteroid, which,however, indicated the complicated interactions of plant hormones. Possible signal transduction pathwaysinvolved in ABA were discussed.展开更多
An HPLC method was used to analyze the contents and variation of IAA,GA3,ABA.and ZT at five stages around the tea shoot germinating in spring.The contents of GAa and ABA had a top value during the winter and decreased...An HPLC method was used to analyze the contents and variation of IAA,GA3,ABA.and ZT at five stages around the tea shoot germinating in spring.The contents of GAa and ABA had a top value during the winter and decreased with the growth of tea shoots,while the contents of IAA and ZT had a low value during the winter and increased quickly at the beginning of shoot growth,but soon afterwards increased slowly or decreased a little.The ratio of hormones was closely related to the growth of tea plant.The study indicated that the ratios of GA3 to ABA and IAA to ABA were at low values during the winter and went up with the shoot genninating.When the activity of roots was weak,the ratio of ZT to IAA had a top value,but went down gradually with luxuriant activity of roots.The ratio of GA3 to ZT had a certain relativity with the shoot genninating,which was at a top value during the winter but went down suddenly at the beginning of shoot genninating.展开更多
The predicted increase of temperature by effect of climatic change （1.5 ℃ to 4.5 ℃）, will affect some berry components. Anthocyanins and flavonols concentration are responsible of wine color. The level of anthocya...The predicted increase of temperature by effect of climatic change （1.5 ℃ to 4.5 ℃）, will affect some berry components. Anthocyanins and flavonols concentration are responsible of wine color. The level of anthocyanin is affected by light intensity, temperature, sugars, growth regulators and vineyard management. Abscisic acid （ABA） increases the synthesis of anthocyanin in grape. The object of study was to evaluate the effect of different temperature in berries in vitro, of two cultivars combined with ABA treatments. The treatments were control （C, water） and ABA treatment （1,000 ppm） and temperature： 25, 33 and 40 ℃. In Cabemet Sauvignon, 25 and 33 ~C did not affect anthocyanin total concentration but 40 ℃ produced a 30% decrease in anthocyanin. ABA treatment increased anthocyanin vs. C at 25 and 33 ℃, mainly due to glucosylated forms. But ABA ＋ 40 ℃ showed a 44-60% decrease in all anthocyanins forms compounds. Response of Malbec to the highest temperature （40 ℃）, at the end of ripening, was different; higher temperature produced only slight decrease of total anthocyanins concentration （decrease of 7%）. Combination of temperature ＋ ABA at 20℃ and 33℃ increased anthocyanin. But ABA ＋ 40℃ decreased glucosylated and cumarylated forms of anthocyanin.展开更多
Seed vigor is a key factor affecti ng seed quality.The mechanical drying process exerts a sign ificant in fluence on rice seed vigor.The initial moisture con tent(IMC)and drying temperature are considered the main fac...Seed vigor is a key factor affecti ng seed quality.The mechanical drying process exerts a sign ificant in fluence on rice seed vigor.The initial moisture con tent(IMC)and drying temperature are considered the main factors affecting rice seed vigor through mechanical drying.This study aimed to determine the optimum drying temperature for rice seeds according to the IMC,and elucidate the mechanisms mediating the effects of drying temperature and IMC on seed vigor.Rice seeds with three different IMCs(20%,25%,and 30%)were dried to the target moisture content(14%)at four different drying temperatures.The results showed that the drying temperature and IMC had significant effects on the drying performance and vigor of the rice seeds.The upper limits of drying temperature for rice seeds with 20%,25%,and 30%IMCs were 45,42,and 38°C,respectively.The drying rate and seed temperature increased sign ificantly with in creasing drying temperature.The drying temperature,drying rate,and seed temperature showed extremely significant negative correlations with germination energy(GE),germination rate,germination index(Gl),and vigor index(VI).A high IMC and drying temperature probably induced a massive accumulation of hydrogen peroxide(H2O2)and superoxide anions in the seeds,enhanced superoxide dismutase(SOD)and catalase(CAT)activity,and increased the abscisic acid(ABA)content.In the early stage of seed germination,the IMC and drying temperature regulated seed germination through the metabolism of H2O2,gibberellin acid(GA),ABA,and a-amylase.These results indicate that the metabolism of reactive oxygen species(ROS),antioxidant enzymes,GA,ABA,and a-amylase might be involved in the mediation of the effects of drying temperature on seed vigor.The results of this study provide a theoretical basis and technical guidance for the mechanical drying of rice seeds.展开更多
Plants are frequently exposed to adverse environments during their life span.Among them drought stress is one of the major threats to agricultural productivity.In order to survive in such unstable environment,plants h...Plants are frequently exposed to adverse environments during their life span.Among them drought stress is one of the major threats to agricultural productivity.In order to survive in such unstable environment,plants have developed mechanisms through which they recognize the severity of the stress based on the incoming environmental stimuli.To combat the detrimental effects of drought,the plants have evolved various strategies to modulate their physio-hormonal attributes.These strategies that can be modulated by shade and microbes contribute to enhancing tolerance to drought and reducing yield loss.Plant hormones,such as abscisic acid,auxin and ethylene have a major role in the shade-and microbe-associated improvement of drought tolerance through their effects on various metabolic pathways.In this process,the CLAVATA3/EMBRYOSURROUNDING REGION-RELATED 25 peptide has a major role due to its effect on ABA synthesis as shown in our regulatory model.展开更多
Maintaining participants in a trial ultimately without dropout helps keep a study on track,saving time,money,and resources.Since 2015,extensive bioequivalence(BE)studies have been carried out in China,while no researc...Maintaining participants in a trial ultimately without dropout helps keep a study on track,saving time,money,and resources.Since 2015,extensive bioequivalence(BE)studies have been carried out in China,while no research about dropout in healthy volunteers has been reported yet.In this retrospective study,1078 healthy volunteers participating in 18 BE studies from March 2016 to February 2019 in one Chinese hospital were included.Information about the healthy participants and BE studies was recorded for analysis.In terms of the dropout reason,poor compliance,adverse event(AE),and loss of follow-up were found to be the three leading causes of dropout,accounting for 78.7%of all dropouts.In terms of associated factors with active dropout,smoking habit(OR=5.790,P<0.001)was significantly associated with increased risk of active dropout,while older age(OR=0.940,P=0.042)and AE except for SAE(OR=0.321,P=0.004)were significantly associated with a decreased risk of active dropout.Strengthening the education on younger participants and participants with a smoking habit,as well as emphasizing the possible adverse reactions and potential risks,might be strategies to reduce active dropout in healthy participants.展开更多
基金Researches were supported by "the State Key Project of Basic Research, G1999011604" "Key Project of Knowledge Innovation, CAS", "the National Natural Science Foundation of China, No.30070073" "National Sciences Foundation of Pan-Deng". We thank Prof.
文摘Phytohormone abscisic acid (ABA) was critical for many plant growth and developmental processesincluding seed maturation, germination and response to environmental factors. With the purpose to detectthe possible ABA related signal transduction pathways, we tried to isolate ABA-regulated genes throughcDNA macroarray technology using ABA-treated rice seedling as materials (under treatment for 2, 4, 8 and12 h). Of 6144 cDNA clones tested, 37 differential clones showing induction or suppression for at least onetime, were isolated. Of them 30 and 7 were up- or down-regulated respectively. Sequence analyses revealedthat the putative encoded proteins were involved in different possible processes, including transcription,metabolism and resistance, photosynthesis, signal transduction, and seed maturation. 6 cDNA clones werefound to encode proteins with unknown functions. Regulation by ABA of 7 selected clones relating to signaltransduction or metabolism was confirmed by reverse transcription PCR. In addition, some clones werefurther shown to be regulated by other plant growth regulators including auxin and brassinosteroid, which,however, indicated the complicated interactions of plant hormones. Possible signal transduction pathwaysinvolved in ABA were discussed.
文摘An HPLC method was used to analyze the contents and variation of IAA,GA3,ABA.and ZT at five stages around the tea shoot germinating in spring.The contents of GAa and ABA had a top value during the winter and decreased with the growth of tea shoots,while the contents of IAA and ZT had a low value during the winter and increased quickly at the beginning of shoot growth,but soon afterwards increased slowly or decreased a little.The ratio of hormones was closely related to the growth of tea plant.The study indicated that the ratios of GA3 to ABA and IAA to ABA were at low values during the winter and went up with the shoot genninating.When the activity of roots was weak,the ratio of ZT to IAA had a top value,but went down gradually with luxuriant activity of roots.The ratio of GA3 to ZT had a certain relativity with the shoot genninating,which was at a top value during the winter but went down suddenly at the beginning of shoot genninating.
文摘The predicted increase of temperature by effect of climatic change （1.5 ℃ to 4.5 ℃）, will affect some berry components. Anthocyanins and flavonols concentration are responsible of wine color. The level of anthocyanin is affected by light intensity, temperature, sugars, growth regulators and vineyard management. Abscisic acid （ABA） increases the synthesis of anthocyanin in grape. The object of study was to evaluate the effect of different temperature in berries in vitro, of two cultivars combined with ABA treatments. The treatments were control （C, water） and ABA treatment （1,000 ppm） and temperature： 25, 33 and 40 ℃. In Cabemet Sauvignon, 25 and 33 ~C did not affect anthocyanin total concentration but 40 ℃ produced a 30% decrease in anthocyanin. ABA treatment increased anthocyanin vs. C at 25 and 33 ℃, mainly due to glucosylated forms. But ABA ＋ 40 ℃ showed a 44-60% decrease in all anthocyanins forms compounds. Response of Malbec to the highest temperature （40 ℃）, at the end of ripening, was different; higher temperature produced only slight decrease of total anthocyanins concentration （decrease of 7%）. Combination of temperature ＋ ABA at 20℃ and 33℃ increased anthocyanin. But ABA ＋ 40℃ decreased glucosylated and cumarylated forms of anthocyanin.
基金Key Research and Development Program of Zhejiang Province(No.2019C02011)the“San Nong Liu Fang”Science and Technology Cooperation Project of Zhejiang Province(No.2018SNLF004),China。
文摘Seed vigor is a key factor affecti ng seed quality.The mechanical drying process exerts a sign ificant in fluence on rice seed vigor.The initial moisture con tent(IMC)and drying temperature are considered the main factors affecting rice seed vigor through mechanical drying.This study aimed to determine the optimum drying temperature for rice seeds according to the IMC,and elucidate the mechanisms mediating the effects of drying temperature and IMC on seed vigor.Rice seeds with three different IMCs(20%,25%,and 30%)were dried to the target moisture content(14%)at four different drying temperatures.The results showed that the drying temperature and IMC had significant effects on the drying performance and vigor of the rice seeds.The upper limits of drying temperature for rice seeds with 20%,25%,and 30%IMCs were 45,42,and 38°C,respectively.The drying rate and seed temperature increased sign ificantly with in creasing drying temperature.The drying temperature,drying rate,and seed temperature showed extremely significant negative correlations with germination energy(GE),germination rate,germination index(Gl),and vigor index(VI).A high IMC and drying temperature probably induced a massive accumulation of hydrogen peroxide(H2O2)and superoxide anions in the seeds,enhanced superoxide dismutase(SOD)and catalase(CAT)activity,and increased the abscisic acid(ABA)content.In the early stage of seed germination,the IMC and drying temperature regulated seed germination through the metabolism of H2O2,gibberellin acid(GA),ABA,and a-amylase.These results indicate that the metabolism of reactive oxygen species(ROS),antioxidant enzymes,GA,ABA,and a-amylase might be involved in the mediation of the effects of drying temperature on seed vigor.The results of this study provide a theoretical basis and technical guidance for the mechanical drying of rice seeds.
基金This work was supported by the National Research,Development and Innovation Office(grant no.K131638)National Natural Science Foundation of China(grant nos.31871552,31671445)Sichuan Science and Technology Program(grant no.2018HH0108).
文摘Plants are frequently exposed to adverse environments during their life span.Among them drought stress is one of the major threats to agricultural productivity.In order to survive in such unstable environment,plants have developed mechanisms through which they recognize the severity of the stress based on the incoming environmental stimuli.To combat the detrimental effects of drought,the plants have evolved various strategies to modulate their physio-hormonal attributes.These strategies that can be modulated by shade and microbes contribute to enhancing tolerance to drought and reducing yield loss.Plant hormones,such as abscisic acid,auxin and ethylene have a major role in the shade-and microbe-associated improvement of drought tolerance through their effects on various metabolic pathways.In this process,the CLAVATA3/EMBRYOSURROUNDING REGION-RELATED 25 peptide has a major role due to its effect on ABA synthesis as shown in our regulatory model.
基金National Major Scientific and Technological Special Project for Significant New Drugs Development(Grant No.2017ZX09304022)。
文摘Maintaining participants in a trial ultimately without dropout helps keep a study on track,saving time,money,and resources.Since 2015,extensive bioequivalence(BE)studies have been carried out in China,while no research about dropout in healthy volunteers has been reported yet.In this retrospective study,1078 healthy volunteers participating in 18 BE studies from March 2016 to February 2019 in one Chinese hospital were included.Information about the healthy participants and BE studies was recorded for analysis.In terms of the dropout reason,poor compliance,adverse event(AE),and loss of follow-up were found to be the three leading causes of dropout,accounting for 78.7%of all dropouts.In terms of associated factors with active dropout,smoking habit(OR=5.790,P<0.001)was significantly associated with increased risk of active dropout,while older age(OR=0.940,P=0.042)and AE except for SAE(OR=0.321,P=0.004)were significantly associated with a decreased risk of active dropout.Strengthening the education on younger participants and participants with a smoking habit,as well as emphasizing the possible adverse reactions and potential risks,might be strategies to reduce active dropout in healthy participants.
