Changes in the composition of free amino acids and sugars of leaf sheath and culm of wheat during uredospore and teleutospore formation of Puccinia graminis tritici.

There were altogether fourteen amino acids in leaf sheath and culm of wheat infected with Puccinia graminis tritici, especially in and around uredial and telial pustules. Valine, tyrosine, and proline, due to their exclusive presence in uredial pustules on leaf sheath and culm of wheat, were involved in the eruption of uredospores of P. graminis tritici. Glutamic acid and dl-threonine were, however, involved in a different manner during uredospore differentiation; their amounts diminishesd parallel to sporulation. The other amino compounds, detected in and around uredial and telial pustules on leaf sheaths and culms, were l-leucine/isoleucine, beta-phenylalanine, beta-alanine, glycine, serine, aspartic acid, homoserine, and glutamine. The amounts of these amino acids either remained the same or were lowered during uredo- and teluto-spores formation, except for serine which increased in its amount. The depletion of these amino compounds indicated their metabolic activity and utilization for uredo- and teleuto-spores differentiation of P. graminis tritici. Sucrose, glucose, and fructose, among sugars, were also utilized as their amounts diminished, for uredo- and teleuto-spores formation.