广西植物
廣西植物
엄서식물
Guihaia
2015年
5期
656-662,630
,共8页
刘爱荣%张远兵%张雪平%王雪娟%黄守程%谢宜勤
劉愛榮%張遠兵%張雪平%王雪娟%黃守程%謝宜勤
류애영%장원병%장설평%왕설연%황수정%사의근
模拟干旱%彩叶草%生长%渗透调节%抗氧化酶
模擬榦旱%綵葉草%生長%滲透調節%抗氧化酶
모의간한%채협초%생장%삼투조절%항양화매
simulated drought stress%Coleus blumei%growth%osmotic adj ustment%antioxidant enzyme
采用盆栽试验，对彩叶草进行 PEG-6000浓度为0(对照)、5％、10％、15％、20％(W/V)模拟干旱胁迫，研究在干旱胁迫下彩叶草的生长、渗透调节能力及抗氧化酶活性的变化。结果表明：与对照相比，随着PEG-6000浓度的增加，鲜质量、干质量、含水量、水势、根系脱氢酶活性、无机离子含量包括 K＋、Na＋、Ca2＋、Mg 2＋等均呈下降趋势；N O－3含量呈先下降后上升趋势；硝酸还原酶活性、可溶性蛋白含量、可溶性糖含量、超氧化物歧化酶活性均呈先上升后下降趋势；脯氨酸含量、游离氨基酸含量、过氧化物酶活性、过氧化氢酶活性、超氧阴离子(O－2?)产生速率、质膜透性则呈上升趋势。因此，模拟干旱胁迫对彩叶草生长有抑制作用，且随着PEG-6000浓度增加，其生长受抑制和水分胁迫程度加重；模拟干旱胁迫下，彩叶草不积累 K＋、Na＋、Ca2＋、Mg 2＋和N O－3等无机离子进行渗透调节，而积累脯氨酸、可溶性蛋白、可溶性糖、游离氨基酸等有机小分子物质进行渗透调节，但这4种小分子物质增加幅度不尽相同；轻度模拟干旱胁迫虽增强彩叶草抗氧化酶活性，但仍表现轻度的氧化伤害；重度模拟干旱胁迫加重彩叶草氧化伤害。研究结果可为彩叶草耐旱生理机制的研究积累资料，也为其节水型栽植和养护提供依据。
採用盆栽試驗，對綵葉草進行 PEG-6000濃度為0(對照)、5％、10％、15％、20％(W/V)模擬榦旱脅迫，研究在榦旱脅迫下綵葉草的生長、滲透調節能力及抗氧化酶活性的變化。結果錶明：與對照相比，隨著PEG-6000濃度的增加，鮮質量、榦質量、含水量、水勢、根繫脫氫酶活性、無機離子含量包括 K＋、Na＋、Ca2＋、Mg 2＋等均呈下降趨勢；N O－3含量呈先下降後上升趨勢；硝痠還原酶活性、可溶性蛋白含量、可溶性糖含量、超氧化物歧化酶活性均呈先上升後下降趨勢；脯氨痠含量、遊離氨基痠含量、過氧化物酶活性、過氧化氫酶活性、超氧陰離子(O－2?)產生速率、質膜透性則呈上升趨勢。因此，模擬榦旱脅迫對綵葉草生長有抑製作用，且隨著PEG-6000濃度增加，其生長受抑製和水分脅迫程度加重；模擬榦旱脅迫下，綵葉草不積纍 K＋、Na＋、Ca2＋、Mg 2＋和N O－3等無機離子進行滲透調節，而積纍脯氨痠、可溶性蛋白、可溶性糖、遊離氨基痠等有機小分子物質進行滲透調節，但這4種小分子物質增加幅度不儘相同；輕度模擬榦旱脅迫雖增彊綵葉草抗氧化酶活性，但仍錶現輕度的氧化傷害；重度模擬榦旱脅迫加重綵葉草氧化傷害。研究結果可為綵葉草耐旱生理機製的研究積纍資料，也為其節水型栽植和養護提供依據。
채용분재시험，대채협초진행 PEG-6000농도위0(대조)、5％、10％、15％、20％(W/V)모의간한협박，연구재간한협박하채협초적생장、삼투조절능력급항양화매활성적변화。결과표명：여대조상비，수착PEG-6000농도적증가，선질량、간질량、함수량、수세、근계탈경매활성、무궤리자함량포괄 K＋、Na＋、Ca2＋、Mg 2＋등균정하강추세；N O－3함량정선하강후상승추세；초산환원매활성、가용성단백함량、가용성당함량、초양화물기화매활성균정선상승후하강추세；포안산함량、유리안기산함량、과양화물매활성、과양화경매활성、초양음리자(O－2?)산생속솔、질막투성칙정상승추세。인차，모의간한협박대채협초생장유억제작용，차수착PEG-6000농도증가，기생장수억제화수분협박정도가중；모의간한협박하，채협초불적루 K＋、Na＋、Ca2＋、Mg 2＋화N O－3등무궤리자진행삼투조절，이적루포안산、가용성단백、가용성당、유리안기산등유궤소분자물질진행삼투조절，단저4충소분자물질증가폭도불진상동；경도모의간한협박수증강채협초항양화매활성，단잉표현경도적양화상해；중도모의간한협박가중채협초양화상해。연구결과가위채협초내한생리궤제적연구적루자료，야위기절수형재식화양호제공의거。
In the present study,Coleus blumei seedlings were treated with PEG-6000 at the concentrations of 5%, 10%,15%,or 20% as the simulated drought stress,and without PEG-6000 treatment as control to investigate the changes of the growth,osmotic adjustment ability and the antioxidant enzyme activities of C.blumei.The results demonstrated that,comparing with the control,the fresh and dry biomass,water content and potential,root dehydro-genase activity and the contents of inorganic ion (K+,Na+,Ca2+,Mg2+)declined gradually as the increase of PEG-6000 concentrations.The content of NO-3 decreased at first and then increased,but lower than that of the control;On the contrary,nitrate reductase (NR)activity,soluble protein content and soluble sugar content increased at first and then decreased,and the contents of the latter two parameters were higher than that of the controls;in addition,proline and free amino acid content elevated in a PEG-6000-dose dependant manner.We noticed that the superoxide dis-mutase (SOD)activities also initially increased and then decreased,and reached the peak under 10%PEG-6000 treat-ment.However,peroxidase (POD)activities,catalase (CAT )activities,O-2?production rates and membrane permea-bility were greatly improved as the increase of PEG-6000 concentrations.Comprehensive analysis showed that moder-ate simulated drought stress (5%-10% PEG-6000)resulted in the decreased absorption of inorganic ion and water in C.blumei root,but enhanced ability of NO-3 reduction,suggesting that the inhibition on growth and the degree of water deficit were not detrimental,and thus ornamental values were hardly impaired.However,severe simulated drought stress (15%-20% PEG-6000),caused significant loss of inorganic ion absorption and deficit of water as well as the decrease of NO-3 assimilation,which further aggravated the inhibitory effect on growth and osmotic srt-ess,and finally destroyed its ornamental value.We observed that C.blumei seedlings did not accumulate inorganic ion,such as K+,Na+,Ca2+,Mg2+ and NO-3 ;however,it indeed accumulated organic small molecules,such as pro-line,soluble protein,soluble sugar and free amino acid,to maintain the osmotic balance in spite of the increasing rate of these molecules were not parallel.Although moderate simulated drought stress could enhance the antioxidant en-zyme activities (SOD,POD and CAT )of C.blumei seedlings,slight oxidative inj uries were observed.As the increase of PEG-6000 concentration,the notable elevation of O-2?generation rate might result from the decreasing activity of SOD,a key enzyme for scavenging O-2?;although POD and CAT ,another two important antioxidant enzymes,could be significantly induced when suffering from the drought stress.As a result of imbalance of these antioxidant en-zymes,the inj ury of membrane lipid peroxidation was inevitable.These findings will provide some useful experimental basis for elucidating the physiological mechanisms of C.blumei drought tolerance,and also contribute to water-saving planting and maintaining of C.blumei in practice.
