Abstract
Abstract In this study three maize (Zea mays L.) genotypes, a single‐cross hybrid and its parents were evaluated for their efficiency to absorb Mn2+ and Cu2+. All experiments were run using excised roots and uptake efficiency was expressed as Vmax and Km. Also, the genotypes were investigated for possible mutual effects between Mn2+ and Cu2+ during their absorption by roots. Vmax values for both Mn2+ and Cu2+ showed that an appreciable heterotic effect occurred, higher for Mn2+ than for Cu2+ At the same time the hybrid displayed with respect to the inbreds higher Km values for Mn2+ and only slightly lower Km values for Cu2+. Hence a clear positive level of heterosis was evidenced with reference to the maximum absorption capacity (Vmax) but not to the affinity (1/Km) for substrates. Cu2+ inhibited uptake of Mn2+ in a non‐competitive fashion (Vmax for Mn2+ fell in the presence of Cu2+ while Km remained constant) and this effect appeared to a lesser extent in the hybrid than in its parentals. At the same tim...
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call