Life cycle and symptoms of helminthosporium drechsler (जीवन चक्र और हेल्मिंथोस्पोरियम ड्रेचस्लेरा के लक्षण)

Life cycle and symptoms of

 helminthosporium Drechsler ( जीवन 

चक्र और हेल्मिंथोस्पोरियम ड्रेचस्लेरा के लक्षण)

Introduction

These regular leaf spot sicknesses experienced in New York are generally ruinous during chilly, wet, cloudy climates, for example, happen during spring and fall. They are likewise regular where turf is sprinkled with water much of the time. Leaf spot organisms cause continuous searing and diminishing or dissolving out of grasses also, if extreme, the whole turf plant might be lost. Crown and root spoiling regularly follow leaf-spotting as the season advances and temperatures rise. Sicknesses brought about by the types of Drechslera and Bipolaris were previously gathered as Helminthosporium leaf spot, crown decay, and root decay. Presently, nonetheless, they have been isolated into a few genera. Numerous types of Drechslera cause what is referred to now as Drechslera leaf spot, crown decay, and root decay.

Symptoms and Signs 

Little, dim earthy colored, purplish, or purplish-red shaded spots show up on the leaves from the late-winter to pre-winter. As these leaf spots increment in size, their focuses may blur to a straw or light-earthy colored tone. The spots are generally encircled by tight dull ruddy earthy colored to purplish-dark fringes. As the sickness advances in a good climate, the spots run together and support the leaf-cutting edges. The crown decay stage shows up with the first warm climate, causing a ruddy earthy colored rot of the crown, rhizome, and root tissues. Plants need force and wither during the early afternoon as the root are pulverized.

Disease Cycle 

The organisms that cause the sickness make due from year to year in dead clippings or tainted grass plants. Spores are delivered in the spring and conveyed to new leaves via air flows, trimmers, sprinkling water, feet, and so on the spores grow in a film of dampness and taint the leaves, causing spots. New leaf contaminations may happen as long as the climate stays soggy and the temperatures are good. With the appearance of a generally dry climate in the late spring, the leaf spot stage diminishes, and crowns and roots are assaulted. Crown and root diseases in midsummer lead to the liquefying out period of the infection and enormous patches of turf might be executed environment and Spread.

Geographic Distribution 

Illnesses brought about by Drechslera spp. have been discovered worldwide and dissemination is associated with having a presence. Leaf spot/liquefying out of Poe pretense's has been found in all areas where the host is used. Red leaf spot has been accounted for in the United States, Australia, and Great Britain. Net smudge is generally appropriated in North America, Europe, Australia, and Asia.

The Executives 

The executives of Drechslera illnesses on cool-season turfgrasses focus on appropriately planned nitrogen applications, limiting leaf wetness term, cutting at fitting statures, and legitimate cultivar choice. 

Social Control 

Leaf spot/softening out illnesses are generally serious on turf that is becoming gradually because of natural burdens. Nitrogen applications that cause exorbitant turf development during the blistering late spring months can incline turfgrass to these sicknesses and result in outrageous diseases. Territories that are widely concealed, need seepage and air development, and are inclined to significant stretches of leaf wetness are more inclined to these illnesses. The water system, cutting, rolling, or dew whipping promptly toward the beginning of the day or utilizing fans can limit leaf wetness span and lessen the rate of this sickness. Leaf spot/dissolving out is especially more serious on lower mown Poa pratensis, so raising cutting statures during contamination periods is important to restrict this illness. 

Substance Control 

A few contact and fundamental fungicides in the benzimidazole, dicarboximide, demethylation inhibitor (DMI), dithiocarbamate, oxidative phosphorylation uncoupler, quinone oxidase inhibitor (QoI), nitrile, and succinate dehydrogenase inhibitor (SDHI) classes give control of Drechslera illnesses. These fungicides must be applied at ordinary control spans during ecological conditions helpful for this sickness.

Demonstrative Methods 

In light of stand side effects, a few different infections might be confused with those brought about by Drechslera spp. For instance, red leaf spot on bentgrasses might be mistaken for anthracnose, copper spot, or Pythium root decay. In many occasions of serious contamination, plentiful sporulation of the microbe likewise happens. Perception of the dull, stretched, multi-shaded spores in contaminated leaf tissue can be made with a hand focal point in the field or with a dismembering magnifying instrument. Brooding for 12-24 h in a mugginess chamber may likewise encourage conidia creation and finding.