LONGEVITY STUDIES WITH WHEAT SEED AND CERTAIN SEED-BORNE FUNGI

Abstract

The longevity of several lots of wheat seed with cracked seed coats was compared, over a period of 17 years, with that of several lots of seed with sound coats. At the beginning of the test the average germination of the first group was 4 per cent lower than that of the second. This difference increased to 12 per cent and remained at that level for about 9 years, but for the last 4 years there was little difference in the germination of the two groups. All seed lots germinated well for about 8 years; then the seed lost its viability with increasing rapidity up to the 15th year, after which it deteriorated more slowly until, at the end of 17 years, nearly all the seed was dead.The longevity of two seed-borne fungi, Helminthosporium sativum, and Alternaria tenuis, on wheat seed was compared. A. tenuis disappeared in about 7 years. H. sativum lost its viability more slowly. Eight per cent of the original amount was present on the seed at the end of 17 years.