CAJ | 학술논문

以紫花苜蓿为研究对象,测定了不同水分处理下牧草刈割后残茬光合作用、膜脂过氧化、渗透调节物质及抗氧化酶类物质的变化,初步探讨了刈割后紫花苜蓿光合变化的机制.刈割后较短时间内紫花苜蓿光合速率(Pn)可恢复甚至上升,气孔导度(gs)也有不同程度的增加;刈割后10 h,紫花苜蓿丙二醛(MDA)含量下降明显,而脯氨酸(proline)含量增加显著;抗氧化酶(SOD、POD和 CAT)活性在刈割后总体迅速上升.不同水分处理下有相同变化趋势,但不同水分处理间差异显著.刈割可能缓解了水分胁迫,减弱了膜脂过氧化程度;渗透调节物质增多,增强了抵抗"刈割"刺激/胁迫的能力;抗氧化酶活性的总体增高,提高了清除"刈割"产生的活性氧的能力,有助于维护光合细胞膜的完整性.总之,细胞膜脂过氧化的减弱、活性氧清除的加强和抵抗胁迫能力的提高,保证了植物器官功能(如气孔运动)的正常甚至超常发挥,从而导致刈割后紫花苜蓿残茬迅速恢复甚至提高光合能力.
이자화목숙위연구대상,측정료불동수분처리하목초예할후잔치광합작용、막지과양화、삼투조절물질급항양화매류물질적변화,초보탐토료예할후자화목숙광합변화적궤제.예할후교단시간내자화목숙광합속솔(Pn)가회복심지상승,기공도도(gs)야유불동정도적증가;예할후10 h,자화목숙병이철(MDA)함량하강명현,이포안산(proline)함량증가현저;항양화매(SOD、POD화 CAT)활성재예할후총체신속상승.불동수분처리하유상동변화추세,단불동수분처리간차이현저.예할가능완해료수분협박,감약료막지과양화정도;삼투조절물질증다,증강료저항"예할"자격/협박적능력;항양화매활성적총체증고,제고료청제"예할"산생적활성양적능력,유조우유호광합세포막적완정성.총지,세포막지과양화적감약、활성양청제적가강화저항협박능력적제고,보증료식물기관공능(여기공운동)적정상심지초상발휘,종이도치예할후자화목숙잔치신속회복심지제고광합능력.
The changes in photosynthetic rate and its mechanism during lucerne (Medicago sativa) regrowth after cutting were investigated in a greenhouse experiment. Photosynthetic rate (Pn), stomatal conductance (gs), contents of malondialchehyche (MDA) and proline, and the activities of superoxidase (SOD), peroxidase (POD) and catalase (CAT) were measured at different soil water availabilities and cutting. Pn and gs increased shortly after cutting. Leaf MDA content decreased 10 h after cutting, while proline content increased. In addition, activity of antioxidases, including SOD, POD and CAT, increased shortly after cutting. The same trend of changes was observed under both water treatments, but significant difference appeared between treatments. It is suggested that cutting stimuli may reduce water stress within the plant body, enhancing osmotic adjustment and clearance of oxygen species, promoting normal functions of plant organs like stomatal movement. Thus, enough CO_2 can be supplied and Pn is then maintained and even enhanced.