The inheritance of glyphosate-resistant goosegrass was studied by making reciprocal crosses between resistant (R) and susceptible (S) biotypes. Eighty-four F₁ hybrids were confirmed using isozyme analyses. Reciprocal F₁ hybrids displayed uniform levels of resistance intermediate (I) to that of the parental types, with no indication of maternal inheritance. The F₁ hybrids were selfed to produce F₂ populations. F₃ populations were produced by selfing resistant and intermediate F₂ phenotypes. A segregation ratio of 1:2:1 (S:I:R) was observed in the F₂ and subsequently in the F₃ generations derived from selfing intermediate F₂ phenotypes. Individuals in F₃ families derived from selfing resistant F₂ phenotypes were resistant. Results from the present study show that glyphosate resistance in goosegrass is inherited as a single, nuclear, and incompletely dominant gene.

Nomenclature: Glyphosate; goosegrass, Eleusine indica L. Gaertn. ELEIN.