The main signs of manifestation of an illness are given in article a stem rust of wheat. Besides, recommendations about methods of fight against it are made.
New and very aggressive look of a wheaten fungus attacks the main grain regions of Iran
New and very aggressive look of a wheaten fungus attacks the main grain regions of Iran. Food and agricultural organization of the United Nations (FAO) declares that the fungus can seriously undermine production of wheat. In headquarters of FAO in Rome warned that distribution of a fungus represents a special peril for such states, as Afghanistan, Pakistan, Turkmenistan, Uzbekistan and Kazakhstan. All of them are large producers of this grain culture and should treat new threat very seriously.
The illness which experts call a stem rust of wheat, is caused by mushroom Ruccinia of graminis. By estimates of FAO, to 80 % of all grades of wheat which are cultivated in the countries of Asia and Africa, are subject to influence of a stem rust. The wind transfers fungus disputes on big distances, without looking at frontiers.
Experts of FAO warn that the fungus can lead to considerable decrease in productivity of wheat in affected countries, They urge to take distribution of a new disease under strict control to reduce risks for the states which were already injured with rise in prices for the grain.
Emergence of a new type of a wheaten fungus was fixed for the first time in Uganda in 1999 and experts name it Ug99. Last year as a result of its distribution wheat crops in Ethiopia and Kenya seriously suffered, and FAO for the first time confirmed presence of a fungus at Yemen. It appeared that it is even more aggressive look of a stem rust, than found in east Africa. Scientists with support
With FAO already work over creation of new grades of wheat steady against a disease. And meanwhile the international experts urge producers to strengthen control of distribution of a wheaten fungus.
Specialists of the State inspectorate in quarantine of plants in AR Crimea note that this fungus isn’t quarantine object, but can appear and on autonomy fields. Further the main signs of its manifestation on plants and fight methods are given.
In the beginning on stalks there are rusty-brown oblong, linear, raising dust small pillows – uredopustuly. After, at the end of wheat vegetation, in education places uredopustul black convex small pillows – teliopustuly are formed.
It is an infecting agent a stem or linear rust – dvudomny mushroom RucciniagraminisPerst.f.sp.triticiEriks.etHenn.
In vegetation of plants, the mushroom can give some generations an uredospor (development of one uredogeneratsiya at 200dlitsya about 7 days), than and speaks fast increase of a disease wheat crops.
By the end of vegetation of wheat on stalks, leaves are formed teliopustuly with teliospor.
Teliospora winter on the remains of the struck plants and sprout only in the spring at temperature 9-29 ° (an optimum 18-22 °) and humidity of air of 95-100 %.
From a teliospor basidiums with bazidiospor are formed. Bazidiospora separate easily and carried by a wind on big distances.
The stem rust is more strongly shown on early crops winter and late crops of summer wheat. Introduction of potash fertilizers, especially in a mix with phosphoric, increases stability of plants against a disease, excessive introduction of nitric fertilizers, on the contrary, promotes its development.
The stem rust is very harmful. It breaks water balance of plants and strengthens a transpiratsiya, weakens photosynthesis, reduces intensity of education and outflow of carbohydrates, reduces growth and detains development of plants.
At strong development of a disease drowning of crops of wheat is possible. Stalk defeat under a cone causes "istekany" grains owing to what it is formed puny, with very poor baking qualities. The illness can cause a shortage of 60-70 % of a crop.
Methods of fight against a stem rust:
1. Bayleton, 25 %, see the item. Spray in vegetation (2 times).
2. Rex, 49,7 %, k.e. Spray in vegetation (2 times).
3. Folikur of BT, 22,5 %, k.e. Spray in vegetation (2 times).