CAJ | 학술논문

为了揭示高、低温及干旱交替对玉米植株生长及渗透调节物质的影响机制,以会单2号幼苗为试材,分别经高温(36℃、40℃)、低温(4℃、8℃)、室温(25℃,CK)预处理72 h,然后进行无土栽培,待苗长至50 cm左右时在营养液中加入15%聚乙二醇( PEG-6000)进行模拟干旱处理。结果表明,高、低温预处理对玉米苗的生长影响较大,其中高温预处理抑制玉米苗在干旱胁迫前的生长,降低生物量积累,但干旱胁迫后高温(36℃、40℃)预处理的玉米苗保持较快的生长速率,株高较干旱胁迫前分别增长了46.7、44.0 cm,生物量分别增长了41.0、37.4 g；而低温预处理却显著促进了玉米苗在干旱胁迫前的生长和生物量积累,但在干旱胁迫过程中表现不明显。高、低温预处理可显著减小玉米根、茎、叶相对含水率和总相对含水量的降幅,显著增加游离脯氨酸、可溶性糖、可溶性蛋白、总氮、钾的含量。干旱胁迫结束时,40℃预处理的玉米植株游离脯氨酸、可溶性糖、可溶性蛋白、总氮、钾含量分别达到1286.31μg/g、75.76 mg/g、11.43 mg/g、32.80 mg/g、12.19 mg/g,显著高于低温处理和CK。因此,低温预处理可促进玉米苗的生长,而高温预处理则抑制其生长,这种作用在干旱胁迫下则逆转。高、低温预处理可诱导玉米植株对干旱胁迫的交叉适应性,这种适应性与渗透调节能力的增强密切相关。
위료게시고、저온급간한교체대옥미식주생장급삼투조절물질적영향궤제,이회단2호유묘위시재,분별경고온(36℃、40℃)、저온(4℃、8℃)、실온(25℃,CK)예처리72 h,연후진행무토재배,대묘장지50 cm좌우시재영양액중가입15%취을이순( PEG-6000)진행모의간한처리。결과표명,고、저온예처리대옥미묘적생장영향교대,기중고온예처리억제옥미묘재간한협박전적생장,강저생물량적루,단간한협박후고온(36℃、40℃)예처리적옥미묘보지교쾌적생장속솔,주고교간한협박전분별증장료46.7、44.0 cm,생물량분별증장료41.0、37.4 g；이저온예처리각현저촉진료옥미묘재간한협박전적생장화생물량적루,단재간한협박과정중표현불명현。고、저온예처리가현저감소옥미근、경、협상대함수솔화총상대함수량적강폭,현저증가유리포안산、가용성당、가용성단백、총담、갑적함량。간한협박결속시,40℃예처리적옥미식주유리포안산、가용성당、가용성단백、총담、갑함량분별체도1286.31μg/g、75.76 mg/g、11.43 mg/g、32.80 mg/g、12.19 mg/g,현저고우저온처리화CK。인차,저온예처리가촉진옥미묘적생장,이고온예처리칙억제기생장,저충작용재간한협박하칙역전。고、저온예처리가유도옥미식주대간한협박적교차괄응성,저충괄응성여삼투조절능력적증강밀절상관。
In order to reveal the action mechanism of alternate treatments with high-low temperature/drought on plant growth and osmoregulation of maize,the seedlings of ‘Huidan 2’ were used as experi-mental materials, which were pretreated under high temperature ( 36 ℃, 40 ℃) and low temperature (4 ℃,8 ℃) for 72 h,taking room temperature (25 ℃) as control. Thereafter the soilless culture of the seedlings was conducted. When the seedlings grew to 50 cm high,15% polyethylene glycol (PEG-6000) was added into the nutrient solution to simulate the drought treatment. The results showed that the high and low temperature pretreatment had a large effect on the growth of maize seedlings. Among them, the high temperature pretreatment inhibited the growth of maize seedlings and decreased the biomass accumu-lation before the drought stress. However,after the drought stress,the maize seedlings pretreated with high temperature (36 ℃, 40 ℃) remained rapid growth, of which the plant height increased by 46. 7 cm and 44. 0 cm respectively,while the biomass increased by 41. 0 g and 37. 4 g respectively. Low temperature pretreatment significantly promoted the growth and biomass accumulation of maize seedlings before the drought stress,but it gradually became not obvious after the drought stress. High and low temperature pre-treatment significantly decreased the relative water contents of roots,stems and leaves of maize,while sig-nificantly increased the contents of proline,soluble sugar,soluble protein,total nitrogen and K+. At the end of the drought stress,the contents of proline,soluble sugar,soluble protein and K+ in maize with 40 ℃pretreatment reached 1 286. 31 g/g,75. 76 mg/g,11. 43 mg/g,32. 80 mg/g,12. 19 mg/g respectively, significantly higher than other treatments and CK. The results suggested that the low temperature pretreat-ment could promote the growth of maize seedlings, and the high temperature pretreatment inhibited the growth,but these effects could be reversed under drought stress. High and low temperature pretreatment could induce the cross adaptation of maize seedlings to drought,and the adaptation might be related to the observed enhance in osmoregulation capability.