Agriculture Reference
In-Depth Information
The Suitability of Different Winter and Spring Wheat Varieties for Cultivation in Organic Farming
http://dx.doi.org/10.5772/58351
against weeds, average level of grain yield and low leaf infestation by fungal pathogens (Table
12). The second cluster grouped 2 varieties: spelt Schwabenkorn and Ostka Strzelecka, with
the lowest grain yield, small wheat density, medium level of infestation by weeds and leaf
diseases. Third cluster was represented only by one variety - Smuga, which was characterized
by the highest yields and the highest stand density and biomass. These parameters of Smuga's
canopy influence its competitiveness against weeds and is reflected in the lowest weed
infestation. If not for its highest leaves infestation index, Smuga would have been recom‐
mended variety for organic system (Table 12).
The most required features of cereal varieties cultivated in organic system are: winter hardi‐
ness, high competitive ability against weeds, tolerance of fungal diseases and ability to take
up and effectively use fertilizers from soil [5-14]. Smuga, due to its winter hardiness, compet‐
itiveness ability against weeds and high yields seems to be suitable for organic farming system.
A little less suitable (considering the same features) are spelt Schwabenkorn and Ostka
Strzelecka. Kobra Plus, Bogatka and Tonacja were the highest yielders in years with good
weather conditions, with optimal plant density and poorer weed pressure. The grain yield of
these varieties was low when there was a high level of weed infestation (180 g m
-2
and more),
as in 2009 and 2010. Kobra Plus and Bogatka was also the less leaf fungal-infested varieties in
organic system in the research period 2008-2010.
3.1.1. Summary
1.
In organic farming system, among the tested varieties, Smuga gave the highest yields (4.26
t ha
-1
), while Ostka Strzelecka was the lowest yielder (3.17 t ha
-1
). Yields of spelt Schwa‐
benkorn were approximately 13% lower than those of modern varieties (glume grain) (3,20
t ha
-1
). Old varieties of common wheat: Ostka Kazimierska, Kujawianka Więcławicka,
Wysokolitewka Sztywnosłoma were not very useful for cultivation in organic system
because of low grain yield and high infestation of leaves.
2.
Yields of winter wheat cultivated in conventional farming system were on average 45%
higher than those produced in organic system. Research conducted in 2005-2007 on
varieties: Roma, Kobra, Zyta, Sukces revealed that average yield differences between
organic and conventional farming system were 19%. Lower yields in organic system,
despite the same sowing rate, were caused by lower number of spikes per m
2
(25% on
average) and slightly lower grains weight (15%).
3.
Weed communities differed in years and between tested varieties. The lowest level of
weed infestation was observed in 2008 (19-46 g m
-2
), whereas the biggest dry matter of
weeds was noted in 2010 (170-345 g m
-2
), which was related to sparse canopies after winter.
The comparison of common wheat and spelt wheat varieties showed the highest level of
weed infestation in Kobra Plus, Bogatka and Tonacja canopies. The lowest number of
weeds at dough stage was shown by Smuga, Ostka Strzelecka and spelt Schwabenkon.
Weed infestation was significantly influenced by wheat plant density, dry matter and
plant height.
4.
Stem base diseases has a lower importance in organic farming system than have leaf
diseases. Kobra Plus and Bogatka showed the highest resistance to leaf fungal diseases.
