CAJ | 학술논문

目的获得生产生物能源的优质原料．方法在田间采用LI-6400便携式光合作用测定仪对‘热研4号’王草Pennisetum purpureum ×P．americanum cv．Reyan No．4和五节芒Miscanthus floridulus的光合特性日变化进行研究，并分析了其净光合速率（ Pn）与主要影响因子的相关性．结果和结论‘热研4号’王草和五节芒的净光合速率日变化均呈“单峰型”，无光合“午休”现象，且‘热研4号’王草日均Pn （25.45μmol · m－2· s－1）略高于五节芒（25.08μmol· m－2· s－1）．2种草的蒸腾速率（Tr）、水分利用效率（WUE）、光能利用率（LUE）和气孔导度（Gs）与Pn一样，最大值均出现在13：00时左右，且‘热研4号’王草的Tr、LUE和Gs也都略高于五节芒，只有WUE略低于五节芒．气孔限制值（Ls）日变化呈正钟型，在11：00时左右达最高值（均为0.86μmol· m－2· s－1），早晚最低，而胞间CO2摩尔分数（xi）日变化趋势与之相反．此外，‘热研4号’王草和五节芒的Pn均与大气CO2摩尔分数（xa）呈显著负相关（P＜0.05），且分别与空气相对湿度（RH）和Gs呈显著正相关（P＜0．05）．以上结果说明‘热研4号’王草的光合能力比五节芒强．
목적획득생산생물능원적우질원료．방법재전간채용LI-6400편휴식광합작용측정의대‘열연4호’왕초Pennisetum purpureum ×P．americanum cv．Reyan No．4화오절망Miscanthus floridulus적광합특성일변화진행연구，병분석료기정광합속솔（ Pn）여주요영향인자적상관성．결과화결론‘열연4호’왕초화오절망적정광합속솔일변화균정“단봉형”，무광합“오휴”현상，차‘열연4호’왕초일균Pn （25.45μmol · m－2· s－1）략고우오절망（25.08μmol· m－2· s－1）．2충초적증등속솔（Tr）、수분이용효솔（WUE）、광능이용솔（LUE）화기공도도（Gs）여Pn일양，최대치균출현재13：00시좌우，차‘열연4호’왕초적Tr、LUE화Gs야도략고우오절망，지유WUE략저우오절망．기공한제치（Ls）일변화정정종형，재11：00시좌우체최고치（균위0.86μmol· m－2· s－1），조만최저，이포간CO2마이분수（xi）일변화추세여지상반．차외，‘열연4호’왕초화오절망적Pn균여대기CO2마이분수（xa）정현저부상관（P＜0.05），차분별여공기상대습도（RH）화Gs정현저정상관（P＜0．05）．이상결과설명‘열연4호’왕초적광합능력비오절망강．
Objective] The purpose of this study was to obtain high quality raw materials for producing biofuels.[Method] Diurnal variation of photosynthetic characteristics of Pennisetum purpureum ×P. americanum cv.Reyan No.4 and Miscanthus floridulus was studied and the correlation between net pho-tosynthetic rate and major impact factors was analyzed using the LI-6400 portable photosynthesis analyzer in the field.[Result and conclusion] The results showed that diurnal variation of the net photosynthetic rate ( Pn) of ‘Reyan No.4’ and M.floridulus showed a “single peak”, with no “midday depression”phenomenon.Pn of ‘Reyan No.4’ (25.45 μmol· m-2· s-1) was slightly higher than that of M.flo-ridulus (25.08 μmol· m-2· s-1).Transpiration rate (Tr), water use efficiency (WUE), light use efficiency ( LUE) and stomatal conductance ( Gs) were similar to Pn and reached the maximum at about 13:00.Tr, LUE and Gs of‘Reyan No.4’ were slightly higher than those of M.floridulus.Diurnal vari-ation of stomatal limitation value (Ls) for both grasses was bell-shaped, reaching the highest value (0.86μmol· m-2 · s-1 ) at about 11:00 and the lowest in the early morning and late afternoon , but diurnal variation of intercellular CO2 mole fraction (xi) was the opposite.Pn of two grasses was negatively corre-lated with atmospheric CO 2 mole fraction ( xa ) ( P<0.05) , and positively correlated with relative air hu-midity ( RH) and Gs ( P<0.05 ) , respectively .These results indicate ‘Reyan No.4 ’ has a stronger photosynthetic capacity than M.floridulus.