Biological invasions have become recognized as one of the greatest threats to ecosystems.Codium,a genus of invasive green algae,has frequent global outbreaks and damages local marine ecosystems.It is now generally acc...Biological invasions have become recognized as one of the greatest threats to ecosystems.Codium,a genus of invasive green algae,has frequent global outbreaks and damages local marine ecosystems.It is now generally accepted that light is one of the main factors affecting the luxuriant growth of macroalgae such as Codium.In this study,to investigate the invasive photo-adaptation strategy of Codium fragile,the photo-adaptation characteristics of C.fragile and Codium.cylindricum from the Nan’ao Island of China were compared and explored.The effect of light intensity on the photosynthetic properties of the two species was investigated:the maximum quantum yield of photosystemⅡ(Fv/Fm)of C.fragile was significantly higher at low light intensity.At a light intensity of 90μmol/(m^(2)·s),maximum relative electron transport rate(rETR_(max))of the thalli was maximum,and the minimum saturating irradiance(Ek)was significantly increased.The photosynthetic rate(αvalue)of thalli was highest at a light intensity of 30μmol/(m^(2)·s).The photochemical quenching(qP)was enhanced but non-photochemical quenching(NPQ)was reduced at high light intensities.As for C.cylindricum,the optimal photochemical efficiency of the thalli at low light intensity was higher.High light intensity significantly reduced the rETR of the thalli.At low light intensity,αwas significantly higher,Ek was significantly lower,and NPQ was also significantly decreased.The response relationship between light acclimation and antioxidant capacity of the thalli of two species of Codium was investigated:there was no significant effect of light intensity variation on the total antioxidant capacity of C.fragile.In the case of C.cylindricum,the degree of membrane lipid peroxidation was significantly increased at low light intensity,and its antioxidant capacity was significantly reduced when the light intensity was too high or too low.It can be hypothesized that the self-protection ability of C.fragile may be stronger than that of C.cylindricum under low and high light intensities,which is closely related to the strong invasiveness of C.fragile.展开更多
基金The National Natural Science Foundation of China under contract Nos 32270219 and 31970216.
文摘Biological invasions have become recognized as one of the greatest threats to ecosystems.Codium,a genus of invasive green algae,has frequent global outbreaks and damages local marine ecosystems.It is now generally accepted that light is one of the main factors affecting the luxuriant growth of macroalgae such as Codium.In this study,to investigate the invasive photo-adaptation strategy of Codium fragile,the photo-adaptation characteristics of C.fragile and Codium.cylindricum from the Nan’ao Island of China were compared and explored.The effect of light intensity on the photosynthetic properties of the two species was investigated:the maximum quantum yield of photosystemⅡ(Fv/Fm)of C.fragile was significantly higher at low light intensity.At a light intensity of 90μmol/(m^(2)·s),maximum relative electron transport rate(rETR_(max))of the thalli was maximum,and the minimum saturating irradiance(Ek)was significantly increased.The photosynthetic rate(αvalue)of thalli was highest at a light intensity of 30μmol/(m^(2)·s).The photochemical quenching(qP)was enhanced but non-photochemical quenching(NPQ)was reduced at high light intensities.As for C.cylindricum,the optimal photochemical efficiency of the thalli at low light intensity was higher.High light intensity significantly reduced the rETR of the thalli.At low light intensity,αwas significantly higher,Ek was significantly lower,and NPQ was also significantly decreased.The response relationship between light acclimation and antioxidant capacity of the thalli of two species of Codium was investigated:there was no significant effect of light intensity variation on the total antioxidant capacity of C.fragile.In the case of C.cylindricum,the degree of membrane lipid peroxidation was significantly increased at low light intensity,and its antioxidant capacity was significantly reduced when the light intensity was too high or too low.It can be hypothesized that the self-protection ability of C.fragile may be stronger than that of C.cylindricum under low and high light intensities,which is closely related to the strong invasiveness of C.fragile.
