Influence of NPK-application to seed-potato crops on the productivity of the progeny
SummaryThe amount of P- and K-application to the seed-potato crop did not show any influence on the chemical composition of the immature harvested tubers, nor on the productivity if used as seed. Nitrogen had a marked influence on the chemical composition of the tubers.Seed from plots with high nitrogen dressing showed a tendency to give fewer main stems. Concerning the productivity of the seed the experiments showed contradictory results. It is concluded that the amount of fertilizer applied to the seed-potato crop is of little importance for the productivity of the progeny.
Nitrate estimates using the Nitrachek Test for precise N-fertilization during plant growth and, after harvest, for quality testing potato tubers
SummaryThe effect of various levels, timing, and form of inorganic and organic nitrogenous fertilizers on the variation in nitrate content of stem bases over time was measured by means of the Nitrachek test in experiments carried out on sandy soils in Bremervörde, Germany (1985–7) and Helsinki, Finland (1987).There were good correlations between fertilizer use and nitrate content in the stem sap, and it was shown to be feasible to derive standard nitrate values which varied with growth stage.Splitting the application of N gave higher yields than applying all the N in the seedbed. The nitrate contents of tubers at harvest were correlated with the intensity of fertilizer use and was influenced by season. Soil N balances showed that splitting the N dressings reduced the soil N content more than applying all the nitrogen at the time of planting.
Handbuch der Landwirtschaft
NOW that the publication of this handbook is complete, it is possible to form the compreheneive view of the whole work that was defeated earlier by its fragmentary method of production. With all the parts in hand, the objection based on non-consecutiveness is reduced to a problem for the bookbinder.Handbuch der Landwirtschaft.Herausgegeben von Fr. Aereboe J. Hansen Th. Roemer. Fünf Bände. Lieferungen 12–25. (Berlin: Paul Parey, 1929.) 5.80 gold marks each part.