460 



Failure of Black Yeo Oats in Glamorgan. [Aug., 



Samples of the grain were subjected to test at the Plant 

 Breeding Station at Aberystwyth together with a sample of 

 Kadnor shire Sprig Oats which had failed to establish itself at 

 that Station. The Radnorshire Sprig, like the Black Yeo, had 

 all the appearance of being a perfectly satisfactory sample — it 

 had no odour and the grain was plump and bright, but in this 

 case the laboratory germination test proved it only to be capable 

 of a growth of 23 per cent. 



A laboratory test conducted at Aberystwyth on the Black Yeo 

 confirmed that of the Official Seed Testing Station, but revealed 

 the fact that the energy of germination (germination in three 

 days) was decidedly poor. Microscopic examination of the ker- 

 nels did not reveal any apparent defect in the embryo. 



A pot experiment was consequently made to investigate the 

 matter in greater detail. The procedure adopted was as follows : — 

 The Black Yeo and Radnorshire Sprig were tested against a 

 sample of Culberson as control. The Culberson had given a 

 perfectly normal laboratory germination of 99 per cent., with a 

 high energy of germination, and the lot from which the sample 

 had been drawn had given rise to a thick " stand " and had 

 made good grow 7 th on the plots. The seed was sown in 5 -in. pots 

 (five seeds per pot). Twenty-five pots constituted a " series." 

 The experiment was set up on 27th June, and subsequently as 

 required one series received " full," i.e., normal watering, and 

 whenever this series was watered a second series was given 

 " half " the normal watering, a third series " quarter " of the 

 normal watering and a fourth series *' double " the normal 

 watering. 



The chief results obtained are set out in the Table hereunder : 



Particulars of Tests. 



Culberson Control : 

 Laboratory germ. 

 99 per cent. 



Radnor Sprig : 

 Laboratory germ. 

 •_'3 per cent. 



Black Yeo : 

 Laboratory germ. 

 97 per cent. 



Per- 

 centage of 

 seedlings 

 17 days 



after 

 planting. 



Final 

 percentage 

 of estab- 

 lished 

 plants 

 33 days 



after 

 planting. 



Per- 

 centage of 

 seedlings 

 17 days 

 after 

 planting. 



Final 

 percentage 

 of estab- 

 lished 

 plants 

 33 days 

 after 

 planting. 



Per- 

 centage of 

 seedlings 

 17 days 

 after 

 planting. 



Final 

 percentage 

 of estab- 

 lished 

 plants 

 33 days 



after 

 planting. 



Normal watering 



97 



98 



16 



IS 



26 



91 



Half watering 



97 



91 



11 



14 



17 



73 



Quarter watering 



75 



87 



13 



14 



2 



25 



Double watering 



97 



86 



5 



(J 



3S 



63 



Difference between : 















Full and half watering 







— 7 



-5 



- 4 



- 9 



-18 



,. „ quarter .. 



- 22 



- 11 



-3 



-4 



-24 



-66 



„ ., double ,, 







- 12 



-11 



- 12 



+ 12 



-28 



( — ) = decrease and (+)=-= increase compared with normal watering. 



