Endophytic fungi from Vitis vinifera L. isolated in Canary Islands and ...

Aspects regarding the physiology of cuscuta (Cuscuta L.Convolvulaceae)Tănase Maria 1 *, Sand Camelia 11 “Lucian Blaga” University of Sibiu*Corresponding author. Email: maritanase@yahoo.comAbstract Many species of Cuscuta contain a small amount of chlorophyll;and while both chlorophyll a and b are present in normal proportions, theyonly occur in a very low concentration. Several authors have demonstratedthe capacity of Cuscuta for photosynthesis, making use of CO2 14 . Fer hasdemonstrated that Cuscuta exposed to strong air illumination, with a CO 2concentration much higher than the normal atmospheric CO 2 concentration,fixes more CO 2 during the photosynthesis process than the amount producedby means of respiration in both independently living seedlings and in the stemexcised from the host.The migration of assimilates is only occurring acropetally, notonly in the case of the plantula, but also in the case of the mature parasite.The entirely acropetal migration of assimilates can be explained by theattracting effect exerted by the terminal sprout, as well as by the lateralsprouts situated on the subterminal part of the branch. The rudimentary rootof the plantula does not have a meristem [19]; [12]; [28]; [23]; and theabsence of a downward migration within the plantula thus appearing to bedetermined by the absence of the radicular meristem [9].Key wordsCuscutasp.,photosynthesis, chlorophylla and b, assimilatetransportResearch on the spreading of cuscuta in South-EastTransylvania – RomaniaTanase Maria 1* , Sand Camelia 1 , Gheorghe Maria 2 , Moise Cristina 1 , Stanciu Mirela 1 ,Antonie Iuliana 11 University “Lucian Blaga” Sibiu; 2 Romanian Academy*Corresponding author. Email: maritanase@yahoo.comAbstract Cuscuta (dodder) species are holoparasitic anthophytes, almostentirely deprived of roots, but having filamentary stems; and attackingnumerous host plants, on which they fix themselves by means of haustoria.The economic losses determined by the presence of the dodder are ratherdifficult to support by developing countries, especially by those which are inneed of agricultural development. In the region on which the research hasbeen carried out, the most common species occurring in grasslands andperennial leguminous forages have been: Cuscuta campestris (Yuncker),Cuscuta epithymum (Murray (L.) Noth.) and Cuscuta trifolii (Babington). Thepresence of Cuscuta on cultures can cause substantial damages not only inour country, but in all countries with a warm and temperate climate, in which itis regarded as a quarantine parasite. [5]The Cuscuta species have developed certain means of adaptation inorder to increase their rate of success: a late seed germination, when hostplantsare relatively well-developed; a rather high degree of independencewhich can ensure its survival during a quite long period of autotrophic life(maximum of one month); the invasion of the host plant by extremelyelaborated and complicated means, etc. Cuscuta disseminates to a largeKey wordsCuscuta sp,. host plants,quarantine parasite,spreading