CAJ | 학술논문

【目的】以南方红壤中储量较大的难溶性铁磷为对象，研究杉木根系细胞壁活化难溶性铁磷的能力，分析林龄、根径级、以及木质部和韧皮部等不同组织部位对杉木根系细胞壁活化铁磷能力的影响情况，以期为南方林区红壤潜在可利用磷素含量的研究提供理论依据。【方法】在福建三明莘口教学林场的10年生杉木幼龄林、22年生杉木中龄林和34年生杉木老龄林中各选择3株平均木作为研究对象，按根直径＜2 mm，2～5 mm，5～10 mm，10～20 mm，20～30 mm，＞30 mm等6个径级进行分组，分别从不同径级根系的木质部和韧皮部中提取细胞壁，采用钼锑抗比色法测定细胞壁对难溶性铁磷活化的有效磷含量，分析比较杉木根系细胞壁活化难溶性铁磷的能力，以及根径级、组织部位及林龄等因子对杉木根系细胞壁活化铁磷的影响。【结果】杉木根系细胞壁对铁磷的活化量为17.67～497.50 mg·kg －1。根径级小于10 mm的根系，其木质部和韧皮部中细胞壁对铁磷的活化能力均高于径级大于10 mm的根系。与同一根径级木质部相比，各林龄杉木根系韧皮部的细胞壁对铁磷活化能力均较高。不同林龄杉木同一根径级的木质部和韧皮部，其提取出的细胞壁对铁磷活化能力均表现为：老龄林＞中龄林＞幼龄林。【结论】杉木根径级、组织部位及林龄等因子对其根系细胞壁活化铁磷的影响均较显著。总体上表现为从径级较小根系提取的细胞壁活化铁磷能力高于径级较大根系；随着林龄的增加，根系对铁磷的活化能力呈逐渐增强的趋势，且韧皮部细胞壁的活化能力明显高于木质部。这可能与细胞壁磷溶解内含物的累积及空间结构特征发育规律有关。由于根直径较小的细根生长发育较快，有利于细胞壁活性物质的形成与积累；而与木质部相比，韧皮部作为植物贮藏组织之一，其化学成分含量明显较高；林龄对根系的生长，特别是对细胞壁内果胶等主要内含物的积累具重要作用。因此，今后应对参与细胞壁合成和重组的基因和蛋白进行系统研究，以期找出逆境胁迫下细胞壁通过释放特异性活性物质等途径的作用机制。【目的】以南方紅壤中儲量較大的難溶性鐵燐為對象，研究杉木根繫細胞壁活化難溶性鐵燐的能力，分析林齡、根徑級、以及木質部和韌皮部等不同組織部位對杉木根繫細胞壁活化鐵燐能力的影響情況，以期為南方林區紅壤潛在可利用燐素含量的研究提供理論依據。【方法】在福建三明莘口教學林場的10年生杉木幼齡林、22年生杉木中齡林和34年生杉木老齡林中各選擇3株平均木作為研究對象，按根直徑＜2 mm，2～5 mm，5～10 mm，10～20 mm，20～30 mm，＞30 mm等6箇徑級進行分組，分彆從不同徑級根繫的木質部和韌皮部中提取細胞壁，採用鉬銻抗比色法測定細胞壁對難溶性鐵燐活化的有效燐含量，分析比較杉木根繫細胞壁活化難溶性鐵燐的能力，以及根徑級、組織部位及林齡等因子對杉木根繫細胞壁活化鐵燐的影響。【結果】杉木根繫細胞壁對鐵燐的活化量為17.67～497.50 mg·kg －1。根徑級小于10 mm的根繫，其木質部和韌皮部中細胞壁對鐵燐的活化能力均高于徑級大于10 mm的根繫。與同一根徑級木質部相比，各林齡杉木根繫韌皮部的細胞壁對鐵燐活化能力均較高。不同林齡杉木同一根徑級的木質部和韌皮部，其提取齣的細胞壁對鐵燐活化能力均錶現為：老齡林＞中齡林＞幼齡林。【結論】杉木根徑級、組織部位及林齡等因子對其根繫細胞壁活化鐵燐的影響均較顯著。總體上錶現為從徑級較小根繫提取的細胞壁活化鐵燐能力高于徑級較大根繫；隨著林齡的增加，根繫對鐵燐的活化能力呈逐漸增彊的趨勢，且韌皮部細胞壁的活化能力明顯高于木質部。這可能與細胞壁燐溶解內含物的纍積及空間結構特徵髮育規律有關。由于根直徑較小的細根生長髮育較快，有利于細胞壁活性物質的形成與積纍；而與木質部相比，韌皮部作為植物貯藏組織之一，其化學成分含量明顯較高；林齡對根繫的生長，特彆是對細胞壁內果膠等主要內含物的積纍具重要作用。因此，今後應對參與細胞壁閤成和重組的基因和蛋白進行繫統研究，以期找齣逆境脅迫下細胞壁通過釋放特異性活性物質等途徑的作用機製。
【목적】이남방홍양중저량교대적난용성철린위대상，연구삼목근계세포벽활화난용성철린적능력，분석림령、근경급、이급목질부화인피부등불동조직부위대삼목근계세포벽활화철린능력적영향정황，이기위남방림구홍양잠재가이용린소함량적연구제공이론의거。【방법】재복건삼명신구교학림장적10년생삼목유령림、22년생삼목중령림화34년생삼목노령림중각선택3주평균목작위연구대상，안근직경＜2 mm，2～5 mm，5～10 mm，10～20 mm，20～30 mm，＞30 mm등6개경급진행분조，분별종불동경급근계적목질부화인피부중제취세포벽，채용목제항비색법측정세포벽대난용성철린활화적유효린함량，분석비교삼목근계세포벽활화난용성철린적능력，이급근경급、조직부위급림령등인자대삼목근계세포벽활화철린적영향。【결과】삼목근계세포벽대철린적활화량위17.67～497.50 mg·kg －1。근경급소우10 mm적근계，기목질부화인피부중세포벽대철린적활화능력균고우경급대우10 mm적근계。여동일근경급목질부상비，각림령삼목근계인피부적세포벽대철린활화능력균교고。불동림령삼목동일근경급적목질부화인피부，기제취출적세포벽대철린활화능력균표현위：노령림＞중령림＞유령림。【결론】삼목근경급、조직부위급림령등인자대기근계세포벽활화철린적영향균교현저。총체상표현위종경급교소근계제취적세포벽활화철린능력고우경급교대근계；수착림령적증가，근계대철린적활화능력정축점증강적추세，차인피부세포벽적활화능력명현고우목질부。저가능여세포벽린용해내함물적루적급공간결구특정발육규률유관。유우근직경교소적세근생장발육교쾌，유리우세포벽활성물질적형성여적루；이여목질부상비，인피부작위식물저장조직지일，기화학성분함량명현교고；림령대근계적생장，특별시대세포벽내과효등주요내함물적적루구중요작용。인차，금후응대삼여세포벽합성화중조적기인화단백진행계통연구，이기조출역경협박하세포벽통과석방특이성활성물질등도경적작용궤제。
[Objective]Aims: The insoluble iron bound phosphate in red soil of southern China was used to study the capacity of cell wall of Chinese fir roots in mobilizing insoluble iron bound phosphate and the impact factors,including forest age,root diameter and tissue structure of Chinese fir root cell wall. This study aims at providing a theoretical basis for fully using potentially available phosphorus content in the forest red soil of southern China.[Method]Methods: In Xinkou Forest Station of Sanming in Fujian,we chose 3 average trees from different aged forests,the 10-year-old as the young forest,22-year-old as middle-aged forest and 34-year-old as old forest of Chinese fir plantations,and classified the roots into 6 classes according to the root diameter,less than 2 mm,2-5 mm,5-10 mm,10-20 mm,20-30 mm,and more than 30 mm. The cell wall was extracted from xylem and phloem of different root classes,respectively. The phosphorus content mobilized by cell-wall from insoluble iron bound phosphate was determined by using the molybdenum antimony colorimetric method,to analyze and compare the ability of cell wall of Chinese fir root in mobilization of insoluble iron bound phosphate,and the influence factors,such as root diameter,tissue structures and forest age.[Result]The mobilizing phosphorus content by Chinese fir root cell wall from insoluble iron bound phosphate was from 17 . 67 mg kg-1 to 497 . 50 mg kg-1 . The xylem and phloem cell wall of less than 10 mm diameter roots had greater ability of activating insoluble iron bound phosphate than that of the more than 10 mm diameter roots. Compared with xylem in each forest age, the phloem cell wall of the same diameter root activated more insoluble iron bound phosphate. There was difference in activating ability of insoluble iron bound phosphate among the different forest ages with the same root diameter,and the ability of cell wall in activating insoluble iron bound phosphate was as follows: old forest > middle-aged forest > young forest.[Conclusion]The factors such as root diameter,tissue structures and forest age of Chinese fir had a significantly impact on the capacity for root cell wall to activate insoluble iron bound phosphate. The smaller diameter roots had greater ability activating insoluble iron bound phosphate than the bigger roots; the older forest had greater ability in activating insoluble iron bound phosphate than the younger,and the cell wall extracted from phloem had significantly greater activation ability than that from the xylem. This would be related to the inclusions accumulation of phosphorus dissolved of the cell wall and development pattern of spatial structure. The rapid growth of fine root would conducive to the formation and accumulation of active substances of cell wall. Phloem is a storage tissue of plants,and it has a higher chemical contents compared with the xylem. The forest age especially plays an important role in accumulation of the main contents like pectin in the cell wall. Thus, it is proposed that the genes and proteins involved in cell wall synthesis and restructuring should be studied and emphasized in the future,to understand the mechanism of cell wall in mobilizing insoluble iron bound phosphate through releasing specific active substances under stress condition.