Articles by Author: J M P Geerthsen

Search results for J M P Geerthsen

We found 3 results for you
  1. Nitrogen fixation of annual temperate clover species determined by the nitrogen difference method

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    The nitrogen fixation ability of Trifolium vesiculosum cv. Amclo and Trifolium subterraneum cv. Mount Barker in pure and mixed stands with Lolium multiflorum cv. Midmar were compared using the nitrogen difference method (NDM). The percentage and quantity of apparent legume‚Äźderived...
  2. An explanation of genotype by environment interaction for maize in South Africa

    An explanation of genotype by environment interaction for maize in South Africa

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    The causes of genotype interaction with the environment was investigated using AMMI (Additive Main Effects and Multiplicative Interaction) analysis. AMMI quantified environments by means of E_IPCA1 (first principal component analysis for environment) such that it was highly significantly correlated (r...
  3. A comparison of collinearity mitigation techniques used in predicting BLUP breeding values and genetic gains over generations

    A comparison of collinearity mitigation techniques used in predicting BLUP breeding values and genetic gains over generations

    Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science
    Collinearity potentially has a negative impact on the prediction of genetic gains in tree breeding programs. This study investigated the reliability and impact of best linear unbiased prediction (BLUP) using various collinearity mitigation techniques and of two computational numerical precisions...