Life Sciences Commons^™

Light And Electron Microscopy Of Resistant And Susceptible Alfalfa Roots Infected By Meloidogyne Hapla, Bernard Al Tait

Theses and Dissertations

Resistant (65-410 and 65-393) and susceptible (breeders Lahontan) alfalfa seedlings were infected with the Northern root-knot nematode, Meloidogyne hapla. Infected roots were fixed, stained, and embedded in plastic for ultrastructural investigations. Sections of plastic embedded tissue, cut at 0.5-1.5 microns for light microscopy investigations, were stained with various histochemical stains to determine the chemical composition of the nematode-altered tissues. In the susceptible cultivar, giant cells were formed by enlargement of nematode-stimulated cells without cell wall lysis. The giant cells became multinucleate by karyonkinesis without cytokinesis. Proplastids in the giant cells became structurally altered to form tubular complexes. The resistant plants …