林业科学
林業科學
임업과학
Scientia Silvae Sinicae
2015年
10期
134-141
,共8页
陈佳妮%廖亮%黄增冠%戴文圣%喻卫武%胡渊渊%吴家胜
陳佳妮%廖亮%黃增冠%戴文聖%喻衛武%鬍淵淵%吳傢勝
진가니%료량%황증관%대문골%유위무%호연연%오가성
气体交换%叶绿素荧光%幼叶%成熟叶%光保护
氣體交換%葉綠素熒光%幼葉%成熟葉%光保護
기체교환%협록소형광%유협%성숙협%광보호
gas exchange%chlorophyll fluorescence%young leaf%mature leaf%photoprotection
【目的】通过比较分析2个发育阶段的香榧和榧树叶片的气体交换参数、叶片氮含量及叶绿素荧光参数的差异，探讨香榧与榧树叶片光合特性及其光保护机制。【方法】以天然林中15年香榧和榧树的幼叶(即萌芽后10天)和成熟叶(即萌芽后50天)为研究对象，通过测定2个发育阶段香榧、榧树叶片的光响应曲线、光合色素含量、叶氮含量、比叶重(SLW)、叶绿素荧光参数的变化。【结果】1)香榧幼叶较榧树幼叶具有较低的最大净光合速率(Amax)、光饱和点(LSP)和较高的 SLW，相对差值分别为40.3%，33.1%和29.7%(P≤0.05)，而香榧成熟叶较榧树成熟叶具有较高的 Amax，LSP和 SLW，相对差值分别为26.3%，40.9%和44.8%(P≤0.05)。2)香榧幼叶和成熟叶较榧树叶片具有较高的氮含量，相对差值分别为32.5%和44.9%( P≤0.05)，却具有较低的光合氮素利用效率(PNUE)，相对差值分别为54.9%和12.8%(P≤0.05)。3)与9：00相比，13：00时(较高光强)香榧和榧树幼叶、成熟叶片的光合速率(Pn)和气孔导度(Gs)均显著降低，Pn 的相对差值分别为33.7%，26.8%，35.1%和44.4%(P≤0.05)，Gs 的相对差值分别为27.7%，23.5%，38.7%和45.0%，但胞间 CO2浓度(Ci)无显著变化(P≥0.05)。4)香榧幼叶较榧树幼叶具有较低的实际光化学量子效率(Y(II))(P≤0.05)，及较高的△pH 和叶黄素调节的热耗散量子效率(Y(NPQ))和类胡萝卜素/总叶绿素含量比值(Car/Chl)和叶绿素 a/叶绿素 b 含量比值(Chla/Chlb)(P≤0.05)；香榧成熟叶较榧树成熟叶具有较高的荧光和不依赖于光的非调节性热耗散量子效率(Y(NO))(P≤0.05)。【结论】具有较低 Amax和 LSP的香榧幼叶，在相同的高光强下较易发生光抑制，但较高光强下(13：00时)其光抑制程度小，主要是由于其能有效地通过增加 Y(NPQ)、Car的形式进行过剩光能的热耗散及通过降低 Chlb含量来减少光能的捕获；具有较高的 Amax和 LSP的香榧成熟叶还需通过 Y( NO)进行过剩光能的耗散。香榧叶片较榧树叶片具有较高的氮含量和较低的光合氮素利用效率( PNUE)，说明分配到非光合组分的氮素较多，因此香榧在生产中要注意氮肥的施用。
【目的】通過比較分析2箇髮育階段的香榧和榧樹葉片的氣體交換參數、葉片氮含量及葉綠素熒光參數的差異，探討香榧與榧樹葉片光閤特性及其光保護機製。【方法】以天然林中15年香榧和榧樹的幼葉(即萌芽後10天)和成熟葉(即萌芽後50天)為研究對象，通過測定2箇髮育階段香榧、榧樹葉片的光響應麯線、光閤色素含量、葉氮含量、比葉重(SLW)、葉綠素熒光參數的變化。【結果】1)香榧幼葉較榧樹幼葉具有較低的最大淨光閤速率(Amax)、光飽和點(LSP)和較高的 SLW，相對差值分彆為40.3%，33.1%和29.7%(P≤0.05)，而香榧成熟葉較榧樹成熟葉具有較高的 Amax，LSP和 SLW，相對差值分彆為26.3%，40.9%和44.8%(P≤0.05)。2)香榧幼葉和成熟葉較榧樹葉片具有較高的氮含量，相對差值分彆為32.5%和44.9%( P≤0.05)，卻具有較低的光閤氮素利用效率(PNUE)，相對差值分彆為54.9%和12.8%(P≤0.05)。3)與9：00相比，13：00時(較高光彊)香榧和榧樹幼葉、成熟葉片的光閤速率(Pn)和氣孔導度(Gs)均顯著降低，Pn 的相對差值分彆為33.7%，26.8%，35.1%和44.4%(P≤0.05)，Gs 的相對差值分彆為27.7%，23.5%，38.7%和45.0%，但胞間 CO2濃度(Ci)無顯著變化(P≥0.05)。4)香榧幼葉較榧樹幼葉具有較低的實際光化學量子效率(Y(II))(P≤0.05)，及較高的△pH 和葉黃素調節的熱耗散量子效率(Y(NPQ))和類鬍蘿蔔素/總葉綠素含量比值(Car/Chl)和葉綠素 a/葉綠素 b 含量比值(Chla/Chlb)(P≤0.05)；香榧成熟葉較榧樹成熟葉具有較高的熒光和不依賴于光的非調節性熱耗散量子效率(Y(NO))(P≤0.05)。【結論】具有較低 Amax和 LSP的香榧幼葉，在相同的高光彊下較易髮生光抑製，但較高光彊下(13：00時)其光抑製程度小，主要是由于其能有效地通過增加 Y(NPQ)、Car的形式進行過剩光能的熱耗散及通過降低 Chlb含量來減少光能的捕穫；具有較高的 Amax和 LSP的香榧成熟葉還需通過 Y( NO)進行過剩光能的耗散。香榧葉片較榧樹葉片具有較高的氮含量和較低的光閤氮素利用效率( PNUE)，說明分配到非光閤組分的氮素較多，因此香榧在生產中要註意氮肥的施用。
【목적】통과비교분석2개발육계단적향비화비수협편적기체교환삼수、협편담함량급협록소형광삼수적차이，탐토향비여비수협편광합특성급기광보호궤제。【방법】이천연림중15년향비화비수적유협(즉맹아후10천)화성숙협(즉맹아후50천)위연구대상，통과측정2개발육계단향비、비수협편적광향응곡선、광합색소함량、협담함량、비협중(SLW)、협록소형광삼수적변화。【결과】1)향비유협교비수유협구유교저적최대정광합속솔(Amax)、광포화점(LSP)화교고적 SLW，상대차치분별위40.3%，33.1%화29.7%(P≤0.05)，이향비성숙협교비수성숙협구유교고적 Amax，LSP화 SLW，상대차치분별위26.3%，40.9%화44.8%(P≤0.05)。2)향비유협화성숙협교비수협편구유교고적담함량，상대차치분별위32.5%화44.9%( P≤0.05)，각구유교저적광합담소이용효솔(PNUE)，상대차치분별위54.9%화12.8%(P≤0.05)。3)여9：00상비，13：00시(교고광강)향비화비수유협、성숙협편적광합속솔(Pn)화기공도도(Gs)균현저강저，Pn 적상대차치분별위33.7%，26.8%，35.1%화44.4%(P≤0.05)，Gs 적상대차치분별위27.7%，23.5%，38.7%화45.0%，단포간 CO2농도(Ci)무현저변화(P≥0.05)。4)향비유협교비수유협구유교저적실제광화학양자효솔(Y(II))(P≤0.05)，급교고적△pH 화협황소조절적열모산양자효솔(Y(NPQ))화류호라복소/총협록소함량비치(Car/Chl)화협록소 a/협록소 b 함량비치(Chla/Chlb)(P≤0.05)；향비성숙협교비수성숙협구유교고적형광화불의뢰우광적비조절성열모산양자효솔(Y(NO))(P≤0.05)。【결론】구유교저 Amax화 LSP적향비유협，재상동적고광강하교역발생광억제，단교고광강하(13：00시)기광억제정도소，주요시유우기능유효지통과증가 Y(NPQ)、Car적형식진행과잉광능적열모산급통과강저 Chlb함량래감소광능적포획；구유교고적 Amax화 LSP적향비성숙협환수통과 Y( NO)진행과잉광능적모산。향비협편교비수협편구유교고적담함량화교저적광합담소이용효솔( PNUE)，설명분배도비광합조분적담소교다，인차향비재생산중요주의담비적시용。
Objective]This paper investigated the differences in photosynthesis characteristics and photo-protection mechanisms between Torreya grandis cv.‘Merrilli’and T. grandis by comparing the characteristics of gas exchange,leaf nitrogen content and chlorophyll fluorescence of the flat young leaves ( young leaves ) and fully grown leaves ( mature leaves) of two species. [Method]We measured the light response curve,photosynthetic pigment content,leaf nitrogen content and chlorophyll fluorescence parameters of young leaves (10 days after budding) and mature leaves (50 days after budding) of T. grandis‘Merrilli’and T. grandis (15 years old) in a natural forest. [Result]The,young leaves of T. grandis‘Merrilli’had significant lower Amax,LSP and higher SLW than that of the young leaves of T. grandis,and the relative difference value was 40. 3%,33. 1% and 29. 7%,respectively (P≤0. 05). However,the mature leaves of T. grandis‘Merrilli’had significantly higher Amax,LSP and SLW than those of T. grandis,and the relative difference value was 26. 3%,40. 9% and 44. 8%,respectively (P≤0. 05). Furthermore,T. grandis cv. ‘Merrilli’had significantly higher leaf nitrogen content than those of T. grandis,and the content was about 32. 5% and 44. 9% higher in young and mature leaf,respectively (P≤0. 05). However,the PNUE in T. grandis cv. ‘Merrilli’were about 54. 9% and 12. 8%lower in young and mature leaf compared to those of T. grandis,respectively. The Pn and Gs in young or mature leaves both of T. grandis and T. grandis cv.‘Merrilli’measured at midday ( at 13:00 pm) were all distinctly lower than those in the morning (at 9:00 am),the relative difference value of Pn was 33. 7%,26. 8%,35. 1% and 44. 4% (P≤0. 05), and the relative difference value of Gs was 27. 7%,23. 5%,38. 7%,45. 0% (P≤0. 05),respectively. No significant changes in Ci(P≥0. 05) were observed. The young leaves of T. grandis cv. ‘Merrilli’had significant higher quantum yield of △pH-and xanthophyll-regulated thermal dissipation (Y(NPQ),),and Car/Chl and Chl a/b ratios (P≤0. 05). The mature leaves of T. grandis cv.‘Merrilli’had significant higher quantum yield of fluorescence and light-independent constitution thermal dissipation (Y(NO)) than T. grandis (P≤0. 05). [Conclusion]The results indicate that young leaves of T. grandis cv. ‘Merrilli’( with lower Amax and LSP compared to T. grandis) mainly dissipate the excess energy through increasing Y(NPQ) and Car,and decreasing Chlb content under high irradiance (at 13:00 pm). The mature leaf of T. grandis cv.‘Merrilli’( with higher Amax and LSP) also needs to increase the Y( NO) to dissipated the excess energy. Significant lower PNUE in leaves of T. grandis cv.‘Merrilli’reminds us to pay more attention to the use of nitrogen fertilizer in future.
