Abai, MR

6th International Congress of DipterologyPhotosynthetic reflectance properties of three cecidomyiidgalls of Machilus thunbergii and Litsea acuminata leavesHuang, M.-Y. (1), H.-M. Chou (1), Y.-T. Chang (1), M.-M. Yang (2) & C.-M. Yang (3)*(1) Department of Life science, National Taiwan Normal University, Taipei, Taiwan 116,ROC(2) Department of Entomology, National Chung-Hsing University, Taichung, Taiwan 402,ROC(3) Research Center for Biodiversity, Academia Sinica, Nankang, Taipei, Taiwan 115,ROC*Corresponding author: cmyang@gate.sinic.edu.twThe aim of this study was to test two hypotheses that leaf-derivedcecidomyiid galls of Machilus thunbergii and Litsea acuminata leaveshave different surface reflectance characteristics from their host leaves, andthat the spectral properties of galls are directly related to photosyntheticprocesses and pigment composition, as well as their host leaves. By usingthe reflectance spectrum from 200-900nm, the reflectance between 280-320nm (R 280-320 ), photosynthetic reflectance index (PRI), red/green ratio(R/G), adjusted normalized difference vegetation index (aNDVI) and coldhard band (CHB), were calculated to investigate the cecidomyiid gallpigment such as chlorophyll, carotenoid and anthocyanin andphotosynthetic properties indicated by Fv/Fm. The R 280-320 suggested thatall galls may reflect more UV radiation than the host leaf to avoid UVdamage. The PRI and R/G data indicated that xanthophyll cycle pigmentsand anthocyanin content are higher in galls than in host leaf. In contrast,the aNDVI and CHB values suggested that chlorophyll content andpigment-protein complexes are much lower in galls than in host leaf. TheFv/Fm ratio also indicated photosystem II is much less efficient in gallsthan in host leaf. Either PRI or CHB is positively correlated to Fv/Fm. Theabove reflectance analysis of three cecidomyiid galls strongly suggestedthat the photosynthetic efficiency of galls is much less than that of hostleaves which is consistent with the results of our earlier analyses showing adeficiency in structures of chlorophyll and pigment protein complexes. Asa result, the spectral reflectance revealed the possibility to be utilized as atool for studying the ecophysiology of galls.117