TITLE:
Root and Foot Rot Diseases of Winter Wheat Grown in Conventional and Organic Systems
AUTHORS:
Jozef Tyburski, Tomasz Kurowski, Ewa Adamiak
KEYWORDS:
Winter Wheat, Root and Foot Rot Diseases, Organic Farming, Conventional, Farming
JOURNAL NAME:
Journal of Agricultural Chemistry and Environment,
Vol.3 No.3B,
July
14,
2014
ABSTRACT: The object of the study was fungous
diseases occurring on roots, leave sheaths and stem base of winter wheat in the
two opposing cropping systems (organic and conventional). The observations were
made in vegetation periods (2007-2009) in the fields of winter wheat in northern
Poland. Every year on each plot of compared farming systems root rot occurred (Fusarium
spp., Gaeumannomyces graminis and other fungi). For the period of 3 years the degree
of disease injury on the roots of winter wheat grown in the conventional system
in the vegetation period increased, while in the organic one remained on pretty
the same level. On average a lot more affected roots, especially in the flowering
stage, occurred on the winter wheat grown in the conventional system. Fusarium foot
rot (Fusarium spp.) developed on the wheat during the entire vegetation period.
It was the most dangerous root and foot rot disease (the highest indexes of injury).
The mean degree of disease injury on leave sheath was on pretty the same level in
the two farming systems, although in investigated vegetation periods differed a
lot, whereas at the bases of stems the pathogen was on the higher level on the wheat
in the conventional system. Also eyespot (Tapesia yallude) developed in the entire
vegetation period of the winter wheat, but its intensity was much lower than in
case of fusarium foot rot. Leave sheaths of the wheat grown in the conventional
system were slightly stronger affected than those grown in the organic system. In
the flowering stage the intensity of the disease in both farming systems became
equal, while in the wax maturity it was considerably higher in the conventional
system. Sharp eyespot (Rhizoctonia spp.) appeared relatively late and occurred only
in two years of investigation. The intensiveness of the disease was definitely higher
on the organic plots. Among the affected roots, taken in the stem elongation stage,
from the organic system 28 cultures of fungi were isolated, and from the conventional
one 24 colonies. Cereals pathogenic fungi amounted 35.8% of isolates obtained from
the organic system and as many as 66.7% from the conventional system. Among the
affected roots, taken in the flowering stage, from the organic system 68 cultures
of fungi were isolated in all, and from the conventional one 25 colonies. Cereals
pathogenic fungi amounted 38.2% of isolates obtained from the organic system and
56.0% from the conventional system. Among the affected stem bases, taken in the
wax maturity stage, from the organic system 56 cultures of fungi were isolated in
all, and from the conventional one 52 colonies. Cereals pathogenic fungi amounted
48.4% of isolates obtained from the organic system and 53.6% from the conventional
system. In the case of all root and foot rot diseases of wheat grown in the organic
system, an advantageous influence of greater biodiversity and number of various
fungi species living in root proximity was noticed as opposed to the conventional
system.