Johannes Auke Postma

Learn More
Themajority of experiments in plant biology use plants grown in some kind of container or pot.We conducted a meta-analysis on 65 studies that analysed the effect of pot size on growth and underlying variables.On average, a doubling of the pot size increased biomass production by 43%. Further analysis of pot size effects on the underlying components of(More)
Observed phenotypic variation in the lateral root branching density (LRBD) in maize (Zea mays) is large (1-41 cm(-1) major axis [i.e. brace, crown, seminal, and primary roots]), suggesting that LRBD has varying utility and tradeoffs in specific environments. Using the functional-structural plant model SimRoot, we simulated the three-dimensional development(More)
Root cortical aerenchyma (RCA) is induced by hypoxia, drought, and several nutrient deficiencies. Previous research showed that RCA formation reduces the respiration and nutrient content of root tissue. We used SimRoot, a functional-structural model, to provide quantitative support for the hypothesis that RCA formation is a useful adaptation to suboptimal(More)
Three–dimensional root architectural models emerged in the late 1980s, providing an opportunity to conceptualise and investigate that all important part of plants that is typically hidden and difficult to measure and study. These models have progressed from representing pre–defined root architectural arrangements, to simulating root growth in response to(More)
BACKGROUND AND AIMS The formation of root cortical aerenchyma (RCA) reduces root respiration and nutrient content by converting living tissue to air volume. It was hypothesized that RCA increases soil resource acquisition by reducing the metabolic and phosphorus cost of soil exploration. METHODS To test the quantitative logic of the hypothesis, SimRoot, a(More)
BACKGROUND AND AIMS During their domestication, maize, bean and squash evolved in polycultures grown by small-scale farmers in the Americas. Polycultures often overyield on low-fertility soils, which are a primary production constraint in low-input agriculture. We hypothesized that root architectural differences among these crops causes niche(More)
Shallow basal root growth angle (BRGA) increases phosphorus acquisition efficiency by enhancing topsoil foraging because in most soils, phosphorus is concentrated in the topsoil. Root hair length and density (RHL/D) increase phosphorus acquisition by expanding the soil volume subject to phosphorus depletion through diffusion. We hypothesized that shallow(More)
BACKGROUND AND AIMS Since ancient times in the Americas, maize, bean and squash have been grown together in a polyculture known as the 'three sisters'. This polyculture and its maize/bean variant have greater yield than component monocultures on a land-equivalent basis. This study shows that below-ground niche complementarity may contribute to this yield(More)
Precise measurements of root system architecture traits are an important requirement for plant phenotyping. Most of the current methods for analyzing root growth require either artificial growing conditions (e.g. hydroponics), are severely restricted in the fraction of roots detectable (e.g. rhizotrons), or are destructive (e.g. soil coring). On the other(More)
Root plasticity in response to the edaphic environment represents a challenge in the quantification of phenotypic variation in crop germplasm. The aim of this study was to use various growth systems to assess phenotypic variation among wild genotypes of Lupinus angustifolius. Ten wild genotypes of L. angustifolius selected from an earlier phenotyping study(More)