Frit fly on a winter rye sowings in the Kirov region
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North-East Agricultural Research Institute, Kirov, Russia
Results of investigations on damage of plants of Falenskaya 4 winter rye by frit fly (Oscinella) in dependence of terms of sowing and seeding rates, as well as studying of pest resistance of 33 perspective varieties are stated in the article. It is established that the greatest harmfulness of Oscinella in the Kirov region is shown on rye crops of early term of sowing which was optimum for central zone of area. Now shift of sowing date for 5-15 days reduces damage of plants by a minimum. The increase in seeding rates (up to 7 million/hectare) or its decrease (down to 3 million/hectare) is not a provocative factor for strengthening of harmfulness of Oscinella.
The early term of sowing of winter grain crops is the principal provocative background for distribution of Oscinella. Studying of a winter rye varieties bred in North-East Agricultural Research Institute in these conditions revealed some populations (Nioba, Snif, Grafinya (2D), Rada, 37/04) which had no death of plants, despite strong distribution of the pest.
On a base of analysis of literature it is recommended to carry out chemical processing of crops by fungicides at phases of seedlings or at fall tillering of a rye at excess of an economic threshold of harmfulness (40-80 flies on 100 waves by a net or 6-10% of damages of main stems). Presowing treatment of seeds with insecto-fungicides is effective also.
Keywords: winter rye, frit fly, harmfulness, damage degree, varieties, resistance, sowing terms, seeding rates