79 



more rapidly. Further, in 1923 oats were again the last to become 

 germinating-ripe," and some samples had not attained that state by 

 the sowing season. In 1924, however, conditions for germination were 

 again especially good, so that the number of plants is, in general, 

 abundant. 



In order to learn the relationship between the germinating capacity 

 of the cut seeds and the germinating energy, in the field, of corresponding 

 untreated seeds, 20 samples of oats, the germinating capacity of which 

 had been ascertained earlier in the season, were, on the 24th May, placed 

 in test under usual conditions at a temperature of 11-14° C. ; simulta- 

 neously, cut seeds were put in test, and six lots of 100 seeds of each sample 

 were sown the same day in our trial field and covered with a layer of soil 

 2J cm. in depth. The soil was very suitable and sufficiently moist. The 

 germination results originally obtained in the laboratory and those 

 obtained for the samples placed in test on the 24th May in the laboratory, 

 and also the results of the tests carried out in the field, are to be found 

 in Table 4 {see page 82). 



On comparing the results of the first and the second laboratory tests 

 it will be seen that the " germinating speed " as well as the capacity for 

 germination, as regards almost all the samples, is larger in the second test, 

 and that the differences are most marked where the germinating capacity 

 was small at the time of the first test. The sample numbered 17, which 

 germinated very poorly, had, however, a smaller germinating capacity at 

 the second than at the first examination which shows that the sample in 

 question does not lack " germinating- ripeness " but that the non- 

 germinated seeds were dead. 



The germination results for the out seeds are almost identical with 

 those for the last test of the untreated seeds, and' by that time it may 

 reasonably be supposed all seeds would have been " germinating-ripe." 

 This shows that the first test of the cut seeds affords an immediate 

 general indication of the germinating capacity which may be expected of 

 the samples when they become " germinating-ripe." 



The results of the field experiments show that, in most cases, the 

 germination in the field was high in proportion to the germinating power . 

 found in the laboratory. Numerous examinations in our control fields 

 have shown that, on an average, about two-thirds of the seed which would 

 have germinated in the laboratory will germinate in the field under 

 normal conditions. The germination in the field last spring was, however, 

 better than usual, as almost four-fifths of the number of seeds germinable 

 in the laboratory germinated in the field. It appears, moreover, that the 

 germination results obtained in the field are proportionate to those 

 obtained for the cut seeds in the first and second laboratory tests, as well 

 as to the germinating capacity of the untreated seeds in the second 

 laboratory test. It is thus possible, immediately after the first examination 

 of the cut seeds, to decide whether or not the bulk is suitable for sowing 

 in the field. 



The Danish State Seed Testing Station intends, therefore, to continue, 

 in futtu-e, to make examinations of cut seeds in addition to the usual 

 tests, and to state on the analysis certificates, in cases where the usual 

 test shows that the bulk is not " germinating-ripe," that, after having 

 been stored, or, if necessary, dried or stirred, the seed will probably reach 

 a germinating capacity corresponding to that found in the cut seeds. 



In order to obtain some information as to when cereal seeds become 

 " germinating-ripe," and how the matter is affected by the degree of 

 ripeness reached by the crop at the time of harvesting, some tests have 

 been carried out on samples of cereals harvested at varying stages of 

 maturity. The samples were taken from two varieties of wheat, three of 

 barley (two two-rowed and one six-roWed) and two of oats, all of which 

 are commonly grown in Denmark, and represented each of these varieties 

 at three different stages of maturity, viz., " green-ripe " (the glumes and 

 pales still greenish, the albumen at the transitional stage from milky to 

 tough), " yellow-ripe " (the glumes and pales almost yellow, albumen of a 



