Species Diversity and Structure of the Dominant Complex of Fusarium Seed Infection of Wheat in the Central Chernozem Region of Russia
A series of studies conducted in 2002 - 2006 and 2010 - 2013 showed that Fusarium species diversity is represented by 18 species, 7 of which belong to the group of dominants, but the most important are 4 species of Fusarium sporotrichioides, F. avenaceum, F. roae, F. сulmorum. The status of ecologically plastic fungi that are common in winter and spring wheat in the Central Chernozem region of Russia have F. sporotrichioides and F. poae (superdominant). F. eguiseti, F. oxysporum, F. proliferatum are a minor group and reach values of the dominant once in 9 years. The change in the ratio of species in the group of dominants was observed in ecologically contrasting years: in extremely dry years the share of F. eguiseti grew, but in the wet years the share of F. culmorum grew (the Tambov region, 2010). The dominant complex in 2010 - 2013 was different from those in 2002 - 2006 and included F. sporotrichioides, F. сulmorum and F. poae, the total share of which amounted to 74.8 %. In moderately and excessively wet years (2004 and 2012) the infection of seeds increased to 15 % and 20 %, respectively, while the proportion of F. avenaceum and F. сulmorum amounted to 75 and 54.5 %, respectively. These species cause infestation of grain ( F. avenaceum, F. сulmorum and explicit), their field diagnosis is complicated, and their removal from seeds is almost impossible, which results in off-season transfer of seeds infestation.