Journalartikel

Jahr der Veröffentlichung: 1979

Seiten: 836-847

Zeitschrift: Journal of Plant Nutrition and Soil Science

Bandnummer: 142

Heftnummer: 6

ISSN: 0044-3263

DOI Link: https://doi.org/10.1002/jpln.19791420609

Verlag: Wiley-VCH Verlag

Abstract: 
Pot experiments with ryegrass were conducted to determine whether the K released from the nonexchangeable soil K fraction will suffice to produce high crop yields. The soil used was a K rich clay soil (2.5 % total K, 1.9% HCl soluble K) with a content of exchangeable K+ of 500 ppm at the beginning of the experiment (Ko treatment). In a 2nd treatment (K1) the level of exchangeable K was raised to 1140 ppm by fertilizer K application. According to the principle of permanent cropping ryegrass was cultivated in both treatments which produced 11 cuts during the experimental period of 2 yr. The amount of K absorbed from the nonexchangeable soil K fraction was higher in the Ko treatment than in the treatment which received fertilizer K. The rate of K uptake from the nonexchangeable soil K fraction increased with depletion of exchangeable soil K. The rate of decrease in exchangeable soil K became low as soon as the content of exchangeable soil K fell below a level of 300 ppm. In this low range of exchangeable K, the K absorbed by plants originated mainly from the interlayer K of the clay minerals. Therefore in the range of < 300 ppm exchangeable soil K, the release rate of nonexchangeable K was more important for crop production than the level of exchangeable soil K. No clear relationship between crop yield and K application has been found for the 1st 7 cuts of ryegrass. The 8th cut yielded a highly significant yield increase in the treatment with K application. The differences in yield between both treatments increased with the following cuts. The level of exchangeable soil K at which at first the significant yield depression in the Ko treatment occurred was 280 ppm. Below this level the release rate of nonexchangeable soil K was not high enough to meet the K demand of the crop. In an additional experimental series with a more dry soil (50% of the maximum water capacity) lower yields were obtained in the Ko treatment as compared with the treatment which receive fertilizer K. K uptake, in particular from the nonexchangeable soil K fraction, was impaired by the dry soil medium.

Harvard-Zitierstil: MENGEL, K. and WIECHENS, B. (1979) EFFECT OF THE NON EXCHANGEABLE SOIL K-FRACTION ON THE YIELD PRODUCTION OF RYE-GRASS, Journal of Plant Nutrition and Soil Science = Zeitschrift für Pflanzenernährung und Bodenkunde, 142(6), pp. 836-847. https://doi.org/10.1002/jpln.19791420609

APA-Zitierstil: MENGEL, K., & WIECHENS, B. (1979). EFFECT OF THE NON EXCHANGEABLE SOIL K-FRACTION ON THE YIELD PRODUCTION OF RYE-GRASS. Journal of Plant Nutrition and Soil Science = Zeitschrift für Pflanzenernährung und Bodenkunde. 142(6), 836-847. https://doi.org/10.1002/jpln.19791420609