RT Journal Article SR Electronic T1 Chlorophyll content and chlorophyll fluorescence as physiological parameters for monitoring Orobanche foetida Poir. infestation on faba bean (Vicia faba L.) JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.10.19.345173 DO 10.1101/2020.10.19.345173 A1 Moez Amri A1 Zouhaier Abbes A1 Imen Trabelsi A1 Michel Edmond Ghanem A1 Rachid Mentag A1 Mohamed Kharrat YR 2020 UL http://biorxiv.org/content/early/2020/10/19/2020.10.19.345173.abstract AB In total, 39 faba bean (Vicia faba L.) advanced lines were evaluated for resistance to broomrape Orobanche foetida under highly infested field conditions. The trials were conducted during two consecutive copping seasons at Oued-Beja Research Station in Tunisia. The advanced lines XAR-VF00.13-1-2-1-2-1 and XBJ90.04-2-3-1-1-1-2A expressed high resistance level to O. foetida exceeding those recorded for resistance checks Najeh and Baraca. Results showed that O. foetida significantly affected the biomass, grain yield, chlorophyll content index (CCI) and the maximum quantum efficiency (Fv/Fm ratio). No significant effect of O. foetida parasitism was observed on host plant water content (WC). O. foetida parasitism significantly affected both CCI and Fv/Fm ratio. CCI decreases varied from 46.4% for the susceptible check Badi and 4.2% and 9.3% observed for the genotypes Baraca and XBJ90.04-2-3-1-1-1-2A. Compared to susceptible check, slight decreases of Fv/Fm ratio were observed for both advanced lines XBJ90.04-2-3-1-1-1-2A and XAR-VF00.13-1-2-1-2-1. Correlation between CCI and Fv/Fm with the resistance to broomrape makes this, easy-to-measure, parameter very useful as a practical screening tool for early parasitism detection, diagnosis and identification and selection of high resistant plants against this pathogen.