H₂O₂Is Required for Optimal Establishment of the<i>Medicago sativa</i>/<i>Sinorhizobium meliloti</i>Symbiosis

Abstract

The symbiotic interaction between Medicago sativa and Sinorhizobium meliloti RmkatB(++) overexpressing the housekeeping catalase katB is delayed, and this delay is combined with an enlargement of infection threads. This result provides evidence that H(2)O(2) is required for optimal progression of infection threads through the root hairs and plant cell layers.