Orthogonal factor planning and evaluating method for the investigation of nickel-uptake of plants in greenhouse experiments
Vágó Imre1 – Tolner László2*
1University of Debrecen, Department of Agricultural
Chemistry and Soil Science
(phone: +36-52-508-410; fax: +36-52-413-385)
2Department for Soil
Science and Agricultural Chemistry, Szent István University
Páter Károly Street, H-2103 Gödöllő,
(phone: +36-30-581-0327; fax: +36-28-522-081)
(Received ; accepted )
Abstract. Investigating the effect of different factors on plant production, we may reveal positive interactions between some factors, but in case of other factors – for example toxic heavy metals – a negative effect can be observed.
A simple model that considers both positive and negative effects was developed by di Gléria. His basic hypothesis was, that the value of the relative minimum factor affects the increment (or even the decrement) of plant production proportionately to its distance from the optimal value. The development of this thesis resulted in relationship that can be characterized by a quadratic parabola. Converting the di Gléria-model to two-factorial we get a multiple full quadratic polynome (Biczók et al., 1994).
The multiple quadratic polynome shaped relationship can be practically defined by the application of the data of an experiment that has been set up on the base of a quadratic orthogonal factor plan.
We investigated in a greenhouse pot experiment the effect and interactions between nitrogen fertilization, nickel loading and liming on the dry matter production of Italian ryegrass (Lolium multiflorum L.), beside this on the nickel concentration of the dry matter and the amount of the nickel amount taken up.
It can be stated that the nickel content of Italian ryegrass is independent from the nitrogen fertilization level, but highly depends on the soil properties, on the level of nickel loading and the amount of lime added. High amount of nickel enters plants especially on light, flimsy soils with a small colloid content. The harmful effect can be reduced by liming.
Keywords: soil, heavy metal, liming, interaction, plant