Abstract
The authors investigated on the quality of seed, germination and hard seed content of milk vetch seed in relation to harvesting time for every five days in the field. 1) The germination percentage of seeds was higher in late harvested seeds than that of early harvested seeds, and also the germination tended to be quicken in late harvested seeds (Fig. 2). 2) Hard seed content in the first harvesting time (I) was 7.9 per cent and it was the lowest. At the harvesting time II, it was 17.2 per cent. At the harvesting time III, it was 18.8 per cent and was the highest. And this time contained about 30 per cent of immatured green pods and about 55 per cent of matured black pods. And at harvesting time IV and V, the hard seed content was 11.9 and 12.0 per cent respectively, and it was lower at these times than those of the immatured stages such as harvesting time II and III (Fig. 3). 3) The percentage of corrupt seeds was higher at early harvesting time. The hard seed content for viable seeds, therefore, came to show the highest at harvesting time II (Fig. 4). And this time contained about 9 per cent of matured black pods and about 63 per cent of immatured green pods (Table 1). 4) The weight of 1000 seeds increased as harvested later, but the increase was not so large in seeds harvested after harvesting time III. And the proportion of large-sized seeds was large in late harvested seeds (Table 2). Although the germination percentage was remarkably low in the seeds of less than 14-meshes, no difference of germination percentage was found in the seeds of 14-meshes or larger seeds. 5) From the experimental results mentioned above, it was generally considered that the seeds harvested and dried at immatured stage have the tendency to hardiness than that of harvested after normal maturation on the stalk.
