TRANSPIRATION DECLINE CURVES AND STOMATAL CHARACTERISTICS OF FABA BEAN GENOTYPES

Nine F-1 crosses of faba bean (Vicia faba L.) and their parental genot ypes were evaluated for transpiration decline curves (TDC) and stomata l characteristics. The most common type of TDC had one inflexion. One parent and three crosses were characterized by TDC of two inflexions, while one cross had TDC without inflexion. The genotypes which exhibit ed TDC with 2 inflexions showed later time to stomatal closure (SC), A lso stomatal and cuticular transpiration rates differ significantly am ong studied genotypes. A model for selecting genotypes with effective water retaining features was suggested. This model includes relative w ater content (RWC) at SC, stomatal density, guard cell length, stomata l pore width at both sides of the leaf, stomatal pore length at lower side and leaflet dry mass.