CAJ | 학술논문

以耐热能力不同的两个爪哇稻Oryza stavia L. ssp. javanica品种IRAT109(耐热)和19 D(热敏感)为试验材料,对两种水稻在人工气候室进行日平均气温为33.5℃的高温处理,研究了高温胁迫对耐热能力不同的两个爪哇稻光合特性和渗透调节物质的影响,旨在揭示全球气候变暖的大背景下,耐热能力不同的爪哇稻品种对高温热害的生理代谢变化规律及响应机制.试验结果显示,高温胁迫引起爪哇稻气孔导度下降,胞间 CO2浓度升高,叶绿素含量降低,最终导致净光合速率下降,并随着胁迫时间延长而呈现逐渐下降的趋势,但耐热品种IRAT109与热敏感品种19 D相比仍能维持较高的光合作用.两种水稻中气孔导度,胞间CO2浓度,叶绿素含量,净光合速率在高温胁迫12 d后与自然温度下的植株相比差异显著.同时,高温胁迫造成两爪哇稻中可溶性糖、可溶性蛋白含量降低,且随着高温胁迫时间的延长而逐渐降低,热稳定蛋白随高温胁迫时间的延长而逐渐升高,脯氨酸含量随高温胁迫时间延长呈现先升高后降低的变化趋势.耐热品种IRAT09在高温胁迫过程中可溶性糖和可溶性蛋白的下降幅度小于热敏感品种19 D,热稳定蛋白和脯氨酸含量的上升水平高于热敏感品种19 D.高温胁迫6 d后两爪哇稻中的可溶性糖,可溶性蛋白和热稳定蛋白含量与自然温度下植株相比差异显著,在高温胁迫第3、6和9天两爪哇稻中脯氨酸含量与自然温度下的植株相比差异显著.研究结果表明,耐热爪哇稻品种在高温胁迫下维持较高的光合特性和较高的渗透调节物质含量是其耐热的生理基础.
이내열능력불동적량개조왜도Oryza stavia L. ssp. javanica품충IRAT109(내열)화19 D(열민감)위시험재료,대량충수도재인공기후실진행일평균기온위33.5℃적고온처리,연구료고온협박대내열능력불동적량개조왜도광합특성화삼투조절물질적영향,지재게시전구기후변난적대배경하,내열능력불동적조왜도품충대고온열해적생리대사변화규률급향응궤제.시험결과현시,고온협박인기조왜도기공도도하강,포간 CO2농도승고,협록소함량강저,최종도치정광합속솔하강,병수착협박시간연장이정현축점하강적추세,단내열품충IRAT109여열민감품충19 D상비잉능유지교고적광합작용.량충수도중기공도도,포간CO2농도,협록소함량,정광합속솔재고온협박12 d후여자연온도하적식주상비차이현저.동시,고온협박조성량조왜도중가용성당、가용성단백함량강저,차수착고온협박시간적연장이축점강저,열은정단백수고온협박시간적연장이축점승고,포안산함량수고온협박시간연장정현선승고후강저적변화추세.내열품충IRAT09재고온협박과정중가용성당화가용성단백적하강폭도소우열민감품충19 D,열은정단백화포안산함량적상승수평고우열민감품충19 D.고온협박6 d후량조왜도중적가용성당,가용성단백화열은정단백함량여자연온도하식주상비차이현저,재고온협박제3、6화9천량조왜도중포안산함량여자연온도하적식주상비차이현저.연구결과표명,내열조왜도품충재고온협박하유지교고적광합특성화교고적삼투조절물질함량시기내열적생리기출.
Exposure of high temperature during anthesis in rice was expected to occur more frequently in future climates. The objectives of this study were to investigate the effects of high temperature stress on the photosynthesis and the osmoregulation substances and to reveal the mechanisms for physiological metabolism change. Two varieties of Oryza stavia L. ssp. javanica IRAT109 (thermo-tolerant) and 19 D (thermo-sensitive) were treated in phytron under high temperature of 33.5 °C. The results showed that the stomatal conductance, chlorophyll content and net photosynthesis rate decreased and the intercellular CO2 concentration increased in both of the varieties during high temperature stress. But the thermo-tolerant variety IRAT109 maintained higher level of photosynthesis than thermo-sensitive variety 19 D. For two varieties, the stomatal conductance, chlorophyll content and net photosynthesis rate in plants under high temperature for 12 d were significant different from those under natural temperature. The soluble sugar and protein contents decreased gradually and the heat stable proteins increased gradually as high temperature gone in both of the varieties during high temperature stress. The proline content increased in the beginning and decreased at the end during high temperature treatment in two varieties of rice. However, the reductions in soluble sugars and proteins in IRAT109 were smaller than those in 19 D, while the increases in heat stable protein and proline content in IRAT109 were greater than those in 19 D. The contents of soluble sugars, soluble proteins and heat stable proteins in plants under high temperature stress for 6 d, 9 d and 12 d were significant different with that under nature condition in both varieties of rice. The content of proline in plants treated for 3 d, 6d and 9d increased significantly than that under natural condition in both varieties of rice. We proposed that maintaining a higher level of photosynthesis and osmoregulation substance was the physiological basis for thermo-tolerance in Oryza stavia L. ssp. javanica.