In vivo labelling of nucleic acids during microsporogenesis in tomato

Methods are described for administering tritiated thymidine and orotic acid to microsporocytes of tomato at early meiotic prophase—I. Of five methods examined, bud inoculation proved to be the most effective for efficient entry and incorporation of precursors and convenience in handling a large population with least disturbance to the meiotic system. Application of this technique could be extended to other plant species having a similar growth habit and floral morphology.