Gamma radiation to mutagenesis induction in natal grass [Melinis repens (Willd.) Zizka]

Abstract

Gamma radiation can be used to know the radiosensitivity range (RSR) of grasses for the genetic improvement by mutagenesis. Natal grass is an invasive species that can be enhanced in forage value and other characteristics. The objective of this study was to determine the optimal dose of radiation with cobalt-60 (⁶⁰Co) to effective mutations in natal grass through the mean lethal dose (LD₅₀) and mean growth reduction (GR₅₀). The study was divided into field, laboratory and greenhouse stages. According to weighted means in LD₅₀ and GR₅₀ of each of the variables, the optimal dose was estimated at 304 Gy. The results set the bases for the application of gamma radiation of ⁶⁰Co to induce characteristics of economic and ecological interest in natal grass.