sodininkystė ir daržininkystė 25(4)

affect proper utilisation of this nutrient (Pisulewska, 1993; Kulig et al., 1997; Pastuszewska,
1997; Martyniak, 2001). Such studies are growing in importance at the
moment, as dieticians recommend substituting some animal protein and fat with
plant nutrients (Lampart-Szczapa, 1997; Pastuszewska and Ochtabiñska, 1995). Increased
demand for high-protein foodstuffs, which can be obtained for example from
pea seeds, meets certain obstacles, both natural as the production of pea is strongly
dependent on the climatic conditions, and economic factors (Pahl i Hoffman, 1995).
Kotecki (1990), Alvino and Leone (1993), Fougereus and Dore (1997), Szukaùa
et al. (1997) point to the fact that seed yield and protein content in seeds of leguminous
plants, including pea, depend not only on genetic factors but also on the weather
conditions (moisture and temperatures). Considering the latter, it is worth noticing
that the literature usually contains information pertaining to the optimum water
and temperature demands of a particular plant species, without making any distinction
between cultivars. This problem has been raised by such authors as Andrzejewska
et al. (2002), Szukaùa et al. (1997), Alvino and Leone (1993), who emphasise the
fact that cultivars not only differ in their morphology and use, but they also respond
differently to meteorological conditions, including temperatures and sunlight, which
are of great importance for accumulation of protein. As far as yield of seeds is
concerned, optimum air humidity and rainfall are more important.
The aim of the present study has been to determine to what extent weather
conditions and seed dressing chemicals, which control plant diseases and pests,
influence the content and yield of protein in seeds of several pea cultivars.
Methods and conditions. The experiment was carried out at the Experimental
and Plant Production Station in Baùcyny near Ostróda, in the years 2004–2006. A
strict, two-factor field trial was established on good wheat soil complex (2), classified
according to the Polish soil classification system as class IIIb. It was rich in
phosphorus and potassium and moderately rich in magnesium. The soil pH was 6.7.
In each year of the trial pea was preceded by cereals.
The variables in the experiment consisted of:
– weather conditions (an independent variable, but characterised by high probability
of variability, especially of average temperatures and rainfalls during subsequent
months of pea vegetation seasons in a three-year trial);
– either no seed dressing chemicals (control plots) or application of plant disease
control preparations (Funaben T, Sarfun T) or disease and pest control preparation
(Super Homai 70 DS);
– two different types of pea cultivars: edible (‘Brylant’ and ‘Wenus’) and field
ones (‘Marych’ and ‘Eurika’).
In each year of the trial, seeds were sown in the first decade of April, using a
row seed drill, with the plant density of 100 plants per 1 square meter. Pea plants
were harvested at two stages, in each year on the same day – 31 st of July. The
volume of yields was assessed at comparable seed moisture content (14%), and the
concentration of total protein was determined in laboratory, with Kjeldahl’s method
applied to average samples collected from replications.
The field experiment was established in a split-plot design, with four replications.
Each plot measured 14.4 m 2 in surface area. The results were processed
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