SEED-TESTING MOTES.

Matamata Record, Volume II, Issue 96, 5 September 1918, Page 1

SEED-TESTING MOTES.

By E. Bruce Levy, Biological Laboratory. In view of the restrictions on export from Britain it is highly probable that all available stocks of turnip, swede, and rape seed at present in store in New Zealand will be drawn upon for the 1918 and 1919 sowings. Importations are still arriving, but there is no doubt that much old stock will of necessity be put into use. The following table of germinationanalyses, compiled from a consideration of 418 samples tested from April to July, gives a good indication of the germination Ccipacity of the lines of turnip, swede, rape, and kale seed at present in store in the Dominion : TniNirs Per Cent.

Note. —The non-specified varieties of turnips are those in which the sender uses a distinguishing mark only. Included in these is a good number of garden varieties. The great necessity for the farmer to know the germination of the seed he is sowing will be obvious from an examination of this table. With low-germinat-ing lines, even if sown thickly, the danger of failure is great, for the vitality even of those seeds which do germinate is low, and consequently establishment of the plants is uncertain. The merchant will be loth to sell his client seed of low vitality, but if it comes to the worst and supplies are really short, then something must be done so that the lowgerminating lines can be utilised with the least harm to the general turnip crops of the country. To mix high-germinating with low-germinating lines seems the most feasible thing to do. This would be preferable to selling each line separately, even if the germination certificate accompanied the seed sold. If even, say, 50 per cent, of a real good germinating (90-100 per cent) i seed be included in a poorgerminating line the resultant take should be quite good. In I the writer's opinion this would )be the best course for merchants * to adopt, even if it be necessary for them to buy high-germinating seed at a fairly high price. It will be obvious, of course, that the mixing should be done only with lines of one variety—Superlative swede with Superlative swede, for instance —and with seed from the same European exporter only. Merchants should aim at as [ high a general germination as possible, and this should in no case be less than 70 per cent. The following table suggests a method of mixing which, while the germination of the resultant mixture would be quite satisfactory, enables much of the poorer seed to be utilized : —■ 90 and 40% seed, proportions, 70% of 90% seed with 30% of 40% seed. Germination result, 75%. 90 and 50% seed, proportions, (30%, of 90% seed with 40% of 50% seed. Germination result, 74%. 90 and 00% seeil, proportions, 50% of each, Germination result, 75%,. 90 and 70% seed, proportions, 40% of 90% seed with 60% of 70% seed. Germination result, 75%. Alternative if a higher standard can be maintained. 90 and 50 0 3. seed, proportions, 80% of 90% seed with 20% of 50% seed. Germination result, 82%. 90 and 00% seed, proportions, 75% of 90% seed with 25% of 00% seed. Gcrininatiou result, 82.5%. 90 and 70% seed, proportions, 70% of 90% seed witli 30% of 70% seed. Germination result, 84%. 90 and 80 per cent, seed, proportions, 55 per cent, of 90 per cent, seed with 45 per cent, of 80 per cent. seed. Germination result, 84.5 per cent. |

For thy many cases in which lines of higher germination than 90 per cent, are available. 98 and 40 per cent, seed, proportions. 00 per cent, of 98 per cent seed with 40 percent, of 40 per cent. seed. Genninaation result, 74.8 per cent. Seed lower than 40 per cent, germination should not be used for such mixing. It must be borne in mind that the mixing of lines as a general practice is not for a moment advocated for normal conditions, but special conditions call for special actions, and if the shortage really becomes acute, then by adoption of the above methods the farmer should be secured against crop failures due to unduly low-germinating seed, while at the same time a supply equal to the requirements of all would be more readily available. The only other method to ensure reasonable security for the farmer is for him to know the germination of the seed he sows, so that in the case of a lowgerminating line a corresponding increase in the amount could be gauged and sown. Apart, however, from the factor of lowvitality seed, increasing the amount sown means a departure by the farmer from his usual procedure, and it is doubtful whether the exigencies of the moment would appear pressing enough for him to alter his established practice based on normal experience.

Green-top Min. Ave. Max Yellow Aberdeen 16 72.7 99 Purple-top Yellow Aberdeen 46 79 99 Pur.-top Mammoth 43 S3.7 97 Devonshire Greystone 80 75.3 98 Hardy Green Globe 29 57.25 93 Imperial Green Globe 12 87.7 99 Lincoln lied Globe 77 93.4 99 Forsterton Hybrid 68 90.75 99 Other varieties 30 70.6 94 Varieties not specified 14 83.5 100 Swedes— Magnum Eonum 31 57 87 Champion 12 73.7 94 Elephant (1 75 87 John Bull 40 75 93 Superlative 12 G3.75 98 Crimson King 45 75.3 96 Other varieties 58 79 87 Varieties not specified 5 77.5 97 Rape— Broad-leaf .Essex 18 87 100 Kale-Thousand-headed and Buda 2 55.5 92