Agriculture Reference
In-Depth Information
2. Material and methods
Paper was established on the base of the authors' results and literature. The authors' field
experiments were conducted according to organic agriculture rules in Agriculture Experi‐
mental Stations of Institute of Soil Science and Plant Cultivation - State Research Institute
and individual organic farms in different parts of Poland. The results of research were statis‐
tically elaborated. The impact of the examined factors experiments on the determined char‐
acteristics were assessed using analysis of variance, the half-intervals of confidence being
determined by Tukey's test at the significance level of α = 0.05.
2.1. The importance of legume-cereal mixtures and benefits from the cultivation
Mixtures of legumes with cereals may be used in different ways. If they are grown for seeds,
they can be used for the production of fodder for monogastric animals (pigs and poultry),
because of the increased protein content compared to the grains of sole cereals. In turn, if they
are cultivated for green forage, they provide valuable roughage for ruminants. They can also
be used for plowing, as green manure.
Mixtures make a better utilization of habitat resources than sole crops. Differentiation in the
size and depth of the root systems of cereals and legumes allows them to utilization water and
nutrients from different soil layers, the result of which is a compensatory growth and devel‐
opment of plants. The research on comparison of mixtures root systems of wheat and barley
with peas sown together in alternate and intersecting rows showed that sowing in alternate
rows was the least favorable [9]. Competition between the components of the mixtures can
involve the access to light. A higher cereal component often results in limiting growth
conditions for the accompanying legume by shading, especially under conditions of increased
nitrogen. In legumes, photosynthesis is then limited and nitrogen uptake is reduced [10].
Studies on mixtures of yellow lupine with triticale and oats have shown that a competitive
potential of a single legume is larger than a single cereal plant, but because of the larger number
of cereals in the mixture, their total pressure on legumes is stronger than the pressure of
legumes on cereals [11]. The strength of interspecific competition depends on the severity of
intraspecific competition, which is largely related to the participation of the individual
components. Mixtures of legumes with cereals create the conditions for the formation of
allelopathic interactions that have a significant influence on the subsequent development of
stand structure and the share of each component in the creation of seeds yield. Secondary
metabolites of root exudates may affect rhisospheric organisms, as well as the neighboring
plants [12]. Studies [13] have shown that water solutions of root exudates of seedlings of wheat,
triticale and barley (an effect of 5 cereal seedlings on 1 seed of legume), after 4 days, strongly
reduced the germination of seeds of pea, vetch, blue and yellow lupine, and after 8 days,
exudates of barley and wheat caused the loss of germination of pea seeds (Table 1).
An additional benefit of growing legume-cereal mixtures is their effect on soil fertility and its
phytosanitary status. Mixtures mitigate the negative effects associated with consecutive
sowing of cereals as they become an element which interrupts the continuity of the crops.
