8th INTERNATIONAL WHEAT CONFERENCE

STATuS of WheAT PAThoSySTemS fRom 1990 To 2009
ANd APPLICATIoNS IN BReedINg foR ReSISTANCe
AT NARdI-fuNduLeA
Ittu M., Cana L., Ittu G.
NARDI Fundulea, 1 N. Titulescu Street, Fundulea, 915200 Romania
E-mail Address of presenting author: ittum@ricic.ro
Evidence of changing impact of pathogens affecting crop stability under predictable climatic
scenarios and introduction of new crop technologies, mainly if not associated with resistant
cultivars, was globally revealed. As a consequence, efficient application of measures used to
predict, prevent and/or control outbreaks became more difficult.
Knowing that the potential impact of crop diseases is the first step toward a better management
of their associated risks, analysis of wheat interactions with its pathogens of breeding
concern, recorded across 20 years at Fundulea (South Romania), is here reported.
The aim of this study is to provide on this base, a better support for reliable present and
perspective breeding solutions for resistance to rust fungi, Fusarium head blight (scab)
and common bunt, permanent breeding goals in our wheat program.
Climatic data available at the National Agricultural Research Development Institute have
shown a continuous deviations of temperatures and water regime, as compared with the
multiannual average (48 years). Although, increase of medium temperature ranged from
0.2 to 2.1°C, while on the contrary, total rainfall and atmospheric humidity were on average
lower with 102 mm and 8.1% respectively, from the normal.
As a rule, higher differences of these parameters on average in the second decade (2000-
2009) were registered.
Wheat/Rusts. A permanent decline of air borne pathogens with high evolutionary rate
that cause rusts of wheat has been noticed. Particularly, occurrence of stem and yellow
rusts has been totally absent or insignificant in this area, since 1995 and 2004, respectively.
That’s why optimal conditions for phenotyping of resistance under both, natural
and artificial field conditions were drastically reduced.
Entirely successful field inoculations were difficult to achieve also in the case of leaf rust
(Puccinia triticina). Inoculating 500-1000 genotypes/year, a variation of disease index
(DI) ranging from 14.1 to 56.3, with an average of 25.4 was found. Significant differences
between values of disease index registered on average in each decade were recorded, respectively
35.2 (1990-1999) and 15.7 (2000-2009). Significant close positive or negative
correlations were found between DI and either, medium temperature (r=-0.54, P=0.01)
and rainfall (r=0.47, P=0.05), during the critical periods for the development of rust attack
(February-June).
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