Chlorophyll content and chlorophyll fluorescence as physiological parameters for monitoringOrobanche foetidaPoir. infestation on faba bean (Vicia fabaL.)

Abstract

AbstractIn total, 39 faba bean (Vicia fabaL.) advanced lines were evaluated for resistance to broomrapeOrobanche foetidaunder 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 toO. foetidaexceeding those recorded for resistance checks Najeh and Baraca. Results showed thatO. foetidasignificantly affected the biomass, grain yield, chlorophyll content index (CCI) and the maximum quantum efficiency (Fv/Fmratio). No significant effect ofO. foetidaparasitism was observed on host plant water content (WC).O. foetidaparasitism significantly affected both CCI and Fv/Fmratio. 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/Fmratio 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/Fmwith 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.