Effect of Broomrape (Orobanche sp.) on yield and contributing traits in Taramira (Eruca sativa)

Abstract

Phelipanche aegyptiaca (Formally is known as Orobanche aegyptiaca) is a serious parasitic weed and a major constraint
on Brassicaceae crops, particularly for Rapeseed and Mustard, which causes about 75-80% of yield losses in India. Effect
of Broomrape on Taramira (Eruca sativa) is a major constraint in its production in Rajasthan. Five Taramira varieties viz. -
RTM 2002, RTM 314, RTM 1351, T 27 and RTM 1355 were evaluated in Orobanche infested fields and uninfected field in
Jobner, Jaipur, Rajasthan. The aim of the study was to determine the critical stage of host plants affected by parasitic weed
and to evaluate resistance level of taramira genotypes. The degree of infection and host resistance level was evaluated at
three host growing stages (flowering, siliqua formation and maturity stages) using different traits like number of Orobanche
emerged per plant, per plot, incidence and severity. The agronomic data such as stand count at emergence, flowering,
siliqua, maturity, plant height, number of siliquae, seeds per siliqua, test weight and seed yield were recorded from ten
randomly selected plants in the field. The analysis of variance showed that there were high significant variations (p < 0.01)
in measured traits between the three host growing stages and among genotypes in agronomic traits. The effect of O.
aegyptiaca on host plant was started from the flowering stage, but the siliqua initiation to seed formation stage is
economically important stage at which actual effect of the parasite was observed in field experiments. The analysis of
variance was carried out for various characters observed under normal and Orobanche stress condition. All the genotypes
exhibited significant differences for all the characters under both the conditions. The pooled analysis of variance also
indicated presence of significant difference among the genotypes for all the characters studied.