Effects of Amino Acids On the Reproduction of Heterodera Rostochiensis

Of several racemic mixtures of amino acids tested, the most toxic to H. rostochiensis and the least toxic to potato plants growing in pots was DL methionine.The D and L forms were equally toxic to the nematodes which became less sensitive as they aged.Methionine did not act directly by contact with the nematode: it had first to be taken up by the host plant and was presumably ingested in sap extracted from giant cells.Although methionine affected populations of H. rostochiensis in field plots, even large amounts did not control it adequately.