77 



ripe," phenomena that are now widely known through existing literature. 

 As has been recognised for some time, cereal seeds that have been to 

 some extent damaged, germinate, as a rule, better than do the other seeds 

 in a bulk which is not " germinating-ripe." Purchasers of malting barley, 

 who wished to ascertain Whether those seeds which did not germinate 

 under normal conditions could be made to do so, shook the seeds so 

 vigorously in a bottle that they became damaged. Mr. Wallden utilised 

 this experience. He cut off that end of the cereal seeds Which is opposite 

 the embryo, and then placed the seeds in test. After this treatment, 

 many of them germinated normally during the usual number of days 

 (10-12). 



In addition to the normal tests of the germinating capacity of cereal 

 seeds (in damp sand in earthenware bowls), tests of small numbers of 

 grains (50 or 100) which were cut as described above, have been carried 

 out at the Danish State Seed Testing Station. When it appeared that 

 those seeds which were not treated in this way germinated slowly and 

 poorly, whereas the cut seeds germinated normally, the following state- 

 ment Was made on the analysis certificates : " The low gemlinating 

 capacity suggests that the sample is not ' germinating-ripe ' ; if it be 

 stored for a period in a dry place it will probably attain a higher germina- 

 ting capacity." The senders of the samples thus knew that there was 

 no reason to reject the goods for seed purpose. 



In our rules for seed testing it is laid down that the seeds shaU not be 

 subjectod to any physical or chemical treatment before the test. It has, 

 therefore, been possible to use the method of cutting the ends of the seeds 

 only for the piu"pose of obtaining information as to whether or not seeds 

 would attain a greater germinating capacity later on ; the method is, for 

 this reason, used only Where the seed is not " germinating-ripe." Under 

 normal conditions, barley and oats generally become " germinating-ripe " 

 in Denmark in October or November. Recent summers have, however, 

 been comparatively moist and cool, and this has prevented cereal seed 

 generally from becoming " germinating-ripe " until towards the sowing 

 season, while oats Were frequently not " germinating-ripe " even at that 

 time. In the Report of the Danish State Seed Testing Station for 1922/23,* 

 the results of a series of examinations of cereal seeds which were not 

 " germinating-ripe " are recorded. 



■ In order to ascertain Whether a sample of cereal seed has sufficient 

 germinating energy (the term " germinating speed " is used in this paper 

 when speaking of germination in the laboratory during about one-third of 

 the whole time fixed for germination tests of the species in question, 

 whereas the term " germinating energy " is employed when speaking of 

 germination in soil, where the seeds have resistance to overcome), We 

 make a special examination When it is desired. The cereal seed is then 

 sown in mould in flower-pots and covered to the> normal depth of about 

 2 J cm. The results shown in Table 1 {see page 81) indicate how important 

 it is that seed Which is about to be sown should have a high " germinating 

 speed " and a large capacity for germination. 



A series of comparative germination tests, at temperatures of from 

 17 to 20° C, as hitherto used in tests of cereal seed, and 11-14° C, 

 respectively, have been carried out on samples of cereal seed received 

 at the Danish State Seed Testing Station during the latter part of 1922 

 and the early months of 1923. Some of the results arrived at are recorded 

 in Table 2 {see page 81). 



It appears from this Table that in each case the largest germiinating 

 capacity and, in seven out of the eight samples, the highest " germinating 

 speed " also, was found at the low temperature. Only in the case of 

 sample " h." was the highest germinating speed found at. the high 

 temperature. For a few other samples which germinated normally, 

 something similar was found to hold good; but, in consideration of the 

 small mmaber of samples for which a better germinating speed was 



* Tidakrift for Planteavl, vol. 30, pp. 329-337. 



