CAJ | 학술논문

研究了我国南亚热带森林5种建群树种UV-B辐射诱导的UV-B吸收物质(在280～320 nm波长下测定)的积累及抗UV-B辐射的可能性保护机制.增补UV-B辐射下,马尾松(Pinus massoniana)针叶的甲醇可溶性提取物和细胞壁的碱提取酚类的含量明显高于正常水平的光辐射下.红椎(Castanopsis hystrix)和厚壳桂(Cryptocarya chinensis)叶片的这些化学物质也升高,意味着增补UV-B辐射刺激UV-B辐射吸收物质的生成,形成抗UV-B辐射的功能性保护结构.然而,自然光下已含有大量细胞壁碱提取酚类的荷木(Schima superba)和藜蒴(Castanopsis fissa),这些化合物在增补UV-B辐射下则见下降,很有可能表皮层细胞壁碱提取酚类被转移到含有较低甲醇可溶性色素的液胞可溶性化合物里,这一现象意示着可能涉及叶肉组织光合机构的保护策略.增补UV-B下,马尾松针叶的叶绿素a和b含量不受影响,而其他4种阔叶树叶片则下降10.7% 到16.8%不等.胡萝卜素对增补UV-B辐射的响应变化不一,红椎和荷木的胡萝卜素水平下降,而马尾松、厚壳桂和藜蒴的胡萝卜素则上升,后者也许与功能性增加激发能耗散有关.结果显示,自然条件下不同树种展示出不同的驯化策略以形成抗UV-B辐射增加的防护机制.表4参29
연구료아국남아열대삼림5충건군수충UV-B복사유도적UV-B흡수물질(재280～320 nm파장하측정)적적루급항UV-B복사적가능성보호궤제.증보UV-B복사하,마미송(Pinus massoniana)침협적갑순가용성제취물화세포벽적감제취분류적함량명현고우정상수평적광복사하.홍추(Castanopsis hystrix)화후각계(Cryptocarya chinensis)협편적저사화학물질야승고,의미착증보UV-B복사자격UV-B복사흡수물질적생성,형성항UV-B복사적공능성보호결구.연이,자연광하이함유대량세포벽감제취분류적하목(Schima superba)화려삭(Castanopsis fissa),저사화합물재증보UV-B복사하칙견하강,흔유가능표피층세포벽감제취분류피전이도함유교저갑순가용성색소적액포가용성화합물리,저일현상의시착가능섭급협육조직광합궤구적보호책략.증보UV-B하,마미송침협적협록소a화b함량불수영향,이기타4충활협수협편칙하강10.7% 도16.8%불등.호라복소대증보UV-B복사적향응변화불일,홍추화하목적호라복소수평하강,이마미송、후각계화려삭적호라복소칙상승,후자야허여공능성증가격발능모산유관.결과현시,자연조건하불동수충전시출불동적순화책략이형성항UV-B복사증가적방호궤제.표4삼29
The accumulation of UV-B absorbing materials (measured at the wavelength band of 280～320 nm) induced by UV-B radiation and possible involvement of a protective screening against UV-B radiation were investigated in five constructive species of low subtropical forest in South China. The methanol soluble extracts and alkali-extractable cell wall-bound phendics were significantly higher in needles of Pinus massoniana under supplementary UV-B radiation than under normal level of sunlight. These compounds were also enhanced in leaves of Castanopsis hystrix and Cryptocarya chinensis, implying that the supplementary UV-B radiation stimulated the synthesis of UV-B radiation absorbing materials, forming a functional protecting screen against UV-B radiation. However, Schima superba and Castanopsi fissa that contained relatively high alkali-extractable cell wall-bound phendics under natural sunlight exhibited a decrease in content of these compounds when exposed to supplementary UV-B radiation, suggesting that under supplementary UV-B radiation the cell wall-phendics in epidermal cell layers might be transformed into soluble compounds in vacuoles where there were lower contents of methanol soluble pigment. This fact assumes that a strategy for protection of photosynthetic apparatus hidden in mesophyll tissue was evolved. Chlorophyll a+b content (μg g-1) was not affected in the needles of P. massoniana and a decrease of 10.7% to 16.8% (mg m-1) occurred in the leaves of the other examined broad-leaved tree species under exposure of supplementary UV-B radiation. Response of carotenoids to supplementary UV-B radiation was variable: The decreased level of carotenoid was observed in C. hystrix and S. superba, and carotenoids were stimulated in P. massoniana, C. chinensis and C. fissa, which might be a functional increase in dissipation of excited energy. The results showed that different acclimation strategies were developed to protect against the increasing UV-B radiation in nature and flavoid screen in the acclimation to UV-B radiation was an important feature of adaptation process in the plants of low subtropical forest. Tab 4, Ref 29