草业科学
草業科學
초업과학
Pratacultural Science
2015年
10期
157-165
,共9页
干旱%生理反应%渗透调节%抗旱性
榦旱%生理反應%滲透調節%抗旱性
간한%생리반응%삼투조절%항한성
drought%physiological response%osmoregulation%drought resistance
为了解不同牧草对干旱胁迫的响应,筛选抗旱性强的牧草种类,试验选用扁穗牛鞭草、高丹草和拉巴豆为材料,盆栽研究了水分胁迫对牧草生长的影响及其生理反应。结果表明,牧草对干旱的响应因牧草种类和生理指标不同而异。随着旱情加剧,3种牧草的生物量持续降低,最大降幅可比对照降低18.29%(牛鞭草)、31.21%(高丹草)和33.55%(拉巴豆)。但是,轻、中度干旱对牛鞭草和高丹草的根系生长影响较小,根冠比增加。牧草地上部生物量减少有益于降低水分消耗,根冠比增加使相对更多的根系参与水分和养分吸收。干旱导致细胞膜破坏,丙二醛含量提高,胞内物质外渗,电导率增加,叶绿素和根系活力降低,进而抑制牧草生长。在干旱条件下,牧草体内的脯氨酸是对照的1.3~8.1倍,可溶性糖和蛋白质含量显著提高,产生渗透调节。干旱还能诱导激活牧草体内的超氧化物歧化酶、过氧化物酶和过氧化氢酶,促进消除游离氧自由基,减轻干旱危害。采用隶属函数法综合评价牧草的抗旱性表明,扁穗牛鞭草的抗旱性最强,拉巴豆次之,高丹草最差。
為瞭解不同牧草對榦旱脅迫的響應,篩選抗旱性彊的牧草種類,試驗選用扁穗牛鞭草、高丹草和拉巴豆為材料,盆栽研究瞭水分脅迫對牧草生長的影響及其生理反應。結果錶明,牧草對榦旱的響應因牧草種類和生理指標不同而異。隨著旱情加劇,3種牧草的生物量持續降低,最大降幅可比對照降低18.29%(牛鞭草)、31.21%(高丹草)和33.55%(拉巴豆)。但是,輕、中度榦旱對牛鞭草和高丹草的根繫生長影響較小,根冠比增加。牧草地上部生物量減少有益于降低水分消耗,根冠比增加使相對更多的根繫參與水分和養分吸收。榦旱導緻細胞膜破壞,丙二醛含量提高,胞內物質外滲,電導率增加,葉綠素和根繫活力降低,進而抑製牧草生長。在榦旱條件下,牧草體內的脯氨痠是對照的1.3~8.1倍,可溶性糖和蛋白質含量顯著提高,產生滲透調節。榦旱還能誘導激活牧草體內的超氧化物歧化酶、過氧化物酶和過氧化氫酶,促進消除遊離氧自由基,減輕榦旱危害。採用隸屬函數法綜閤評價牧草的抗旱性錶明,扁穗牛鞭草的抗旱性最彊,拉巴豆次之,高丹草最差。
위료해불동목초대간한협박적향응,사선항한성강적목초충류,시험선용편수우편초、고단초화랍파두위재료,분재연구료수분협박대목초생장적영향급기생리반응。결과표명,목초대간한적향응인목초충류화생리지표불동이이。수착한정가극,3충목초적생물량지속강저,최대강폭가비대조강저18.29%(우편초)、31.21%(고단초)화33.55%(랍파두)。단시,경、중도간한대우편초화고단초적근계생장영향교소,근관비증가。목초지상부생물량감소유익우강저수분소모,근관비증가사상대경다적근계삼여수분화양분흡수。간한도치세포막파배,병이철함량제고,포내물질외삼,전도솔증가,협록소화근계활력강저,진이억제목초생장。재간한조건하,목초체내적포안산시대조적1.3~8.1배,가용성당화단백질함량현저제고,산생삼투조절。간한환능유도격활목초체내적초양화물기화매、과양화물매화과양화경매,촉진소제유리양자유기,감경간한위해。채용대속함수법종합평개목초적항한성표명,편수우편초적항한성최강,랍파두차지,고단초최차。
The aim of this study was to evaluate the drought stress responses of various forages and to select forage cultivars with high drought resistance.A pot experiment was carried out to study the effects of drought stress on the growth and physiology of Hemarthria compressa ,Sudangrass (a Sorghum hybrid),and Dolichos lab lab .The drought responses,as measured using various physiological indices,differed among the three for-ages.The biomass of the three forages continuously decreased as the duration of the drought treatment extend-ed.The maximum decrease in biomass under drought,as compared with their respective controls,was 18.29% for H .compressa,31.21% for Sudangrass,and 33.55% for D .lab lab .Light and medium drought treatments had little effect on the root growth of H .compressa and Sudangrass,but increased their root:shoot ratios.The decrease in shoot biomass under drought reduced water consumption,and the increased root:shoot ratios increased the water and nutrition absorption capacity of the plants.The drought treatments damaged cell membranes and increased the malondialdehyde content,resulting in leakage of intracellular materials,increased relative electric conductivity,reduced chlorophyll content,and lower root activity,all of which inhibited growth of the three forages.Under drought stress,the proline content in tissues of the three forages was 1.3-8.1 times that in their respective controls,and there were significant increases in soluble sugar content and sol-uble protein content,which aided osmotic adjustment.The drought treatments also promoted the activity of antioxidant enzymes (superoxide dismutase,peroxidase,and catalase)in the three forages.The increased an-tioxidant enzyme activities helped to eliminate free oxygen radicals to mitigate drought damage.A comprehen-sive evaluation of the drought resistance of the three forages using the membership function method ranked their drought resistance,from strongest to weakest,as follows:H .compressa>D .lab lab >Sudangrass.