1922.] 



Germination of Indigenous Seeds. 



121 



abundant. The grain weight (vvt. per 1,000 seed) has in all 

 cases been taken on " heavy " seed and not on the sample 

 as a whole. This plan has been adopted in view of the fact 

 that the indigenous seed both collected and " once grown " 

 has not been well cleaned or in any way dressed, thus a 

 " heavy " seed grain weight gives a more accurate comparison 

 between indigenous (collected and " once grown ") and com- 

 mercial than a grain weight based on the weight of 1,000 seeds 

 taken from a sample before removing the " light " seed. The 

 grain weight figures given for commercial samples are of 

 necessity based on special tests made at Aberystwyth and have 

 been obtained for the most part on high-grade seed which 

 has been used in connection with the nationality trials con- 

 ducted at the Plant Breeding Station.* 



It will be seen that the germination of the indigenous 

 grasses collected from various habitats is in the main very low — 

 the average of all the samples together being only about 50 per 

 cent. Individual samples, however, gave high figures; this 

 was particularly so in the case of Timothy and crested dogs- 

 tail. The low germination is very largely due to the consider- 

 able amount of light seed present, which in all cases averagrs 

 more than that found in commercial samples. The germina- 

 tion of heavy seed was, however, also found to be lower than 

 that of heavy commercial seed. One reason, and perhaps the 

 chief reason of the relatively poorer germination of collected 

 than of commercial seed, is undoubtedly the result of greater 

 injury by the grubs of various insects. This was particularly 

 marked in the case of cocksfoot — the seed of which suffered in 

 a marked degree from attacks by the larva? of Glyphipteryx 

 fischcricUa. The attack was greatest on plants growing in 

 thickets and relatively shaded places. Meadow foxtail showed 



* The average figures given in the first, second and third Annual Reports 

 of the Official Seed Testing Station are not generally applicable to the 

 comparisons here made, for the reason that grain weight, percentage of In avj 

 seed and germination figures for the different nationalities of the grasses are 

 not recorded. Average figures from the reports in respect of germination have 

 however in some cases been drawn upon: the reports in question should be 

 referred to: See First Annual Report in this Journal. Vol. XXV (6), September, 

 1918, Second Annual Report, ibid. Vol. XXVI (<)). December, 1919, and Third 

 Annual Report, ibid., Supplement No. 20. The majority of the Aberystwyth 

 tests have been made specially in connection with the work under review; 

 results previously recorded have, however, also been drawn upon, Bee, i '/.. 

 Stapledon, " Seed Studies," Journal Agricultural Science Vol. X (1), June 1920, 

 and report on the "Condition of the Seed Trade in the Aberystwyth College 

 area" — Univ. Coll. of Wales, Aberystwyth, Bulletin, — February, T.'l I. Results 

 of tests made by Jenkin (sec "Seed Testing and RepOli Oil Seeds Tested 

 1013"; Univ. Coil, of N. Wales. Bangor, Bulletin) have also been drawn upon 

 in arriving at some of the average figures. 



