The present study was carried out at field scale to predicte the relative uptake of some nutrient elements as a function of relative growth rate{RGR). The test crop
was Broad bean (Vicia faba, L.) variety Giza 461. The obtained results Indicate that
the dry matter production can be expressed as a Guissian model. The constants of
the model represent the maximum dry matter production and the plant age at
maximum dry matter production{R2 = 0.996··). The nutrients uptake (U) was
regressed against the dry matter production (OM) .The three-order polynomial
equation was found to be the best filling equation. The relationship between relative
growth rate (RGR) and relative accumulation rate(RAR) was filled for each nutrient as
a linear regression model. The model discussed here provides a means for prediding
uptake rate if growth rate are known or can be predicted. Further studies must be
done to explain the factors that have a significant effect on the slope of RGR-RAR
relationship such as plant age. environmental factors, the response of different plant
parts to nutrient uptake and the nutrient availability and mobility in soil system as
related to soil properHes. MODELING NUTRIENTS UPTAKE AS A FUNCTION OF
PLANT GROWTH RATE Hussein, A. H. A. Faculty of Agriculture (Saba Bacha) - Alexandria University· EGYPT ABSTRACT The present study was carried out at field scale to predicte the relative uptake
of some nutrient elements as a function of relative growth rate{RGR). The test crop
was Broad bean (Vicia faba, L.) variety Giza 461. The obtained results Indicate that
the dry matter production can be expressed as a Guissian model. The constants of
the model represent the maximum dry matter production and the plant age at
maximum dry matter production{R2 = 0.996··). The nutrients uptake (U) was
regressed against the dry matter production (OM) .The three-order polynomial
equation was found to be the best filling equation. The relationship between relative
growth rate (RGR) and relative accumulation rate(RAR) was filled for each nutrient as
a linear regression model. The model discussed here provides a means for prediding
uptake rate if growth rate are known or can be predicted. Further studies must be
done to explain the factors that have a significant effect on the slope of RGR-RAR
relationship such as plant age. environmental factors, the response of different plant
parts to nutrient uptake and the nutrient availability and mobility in soil system as
related to soil properHes.