Physiological Effect of Plant Growth Regulators IBA and NAA on Flowers Dropping of Broad Bean (Vicia faba L.)

Abstract

A study was conducted of the winter season 2012-2013 in Kifri city-Kurddistan Region- Iraq to study role of plant growth regulators IBA and NAA in reducing flower dropping two cultivars of faba bean (Local and Spanish).and its effect on seed yield and protein percentage. Split split plots design was used with three replicates. The main plots included the cultivars(Local and Spanish).While sub plots were the plant growth regulators(IBA and NAA).The sub-sub plots represented four dates of plant growth regulators application: Control (No application),Soaking of seed sowing in the solution of IBA (150 ppm) and NAA (150 ppm). spraying the plant at branching stage and beginning of flowering. Results indicated superior Spanish cultivar with NAA in the beginning of flowering in leaf content from total chlorophyll reached (12.25 mg/g dry weight) and lowest percentage of dropped flowers by(68.1%)and higher seed yield/plant reached (21.3gm).The local cultivar treated with IBA in the same stage gave higher leaf area index by(0.86) While Spanish cultivar treated with IBA at branching stage gave highest seed content percentage of protein by(20.63%).