The Gazetteers Department

In addition to the damage done by the pests, the crops suffer from various diseases. The following are the important diseases of various crops in Bhandara district.

Of Cereals.— Kani, Kajali : Spacelotheca sorghi, locally known as kani or danekani, and spacelotheca crucuta, locally called kajali are smuts of jowar. These are responsible for extensive damage to jowar crop in the district. The disease kani cannot be recognised until the ears come out. The diseased earheads do not form normal grains and in place of grains, black masses are formed. These black masses are called ' sori' and contain black powder which consists of millions of spores of the fungus. Threshing together of diseased and healthy earheads is the source of infection. It attacks kharif crop in September—November and rabi crop in December—February. The present method of controlling it is by treating the seed with 200—300 mesh fine sulphur at the rate of one ounce of sulphur to 6.795 kilograms (15 lbs.) of seed.

The symptoms of Kajali are pretty nearly the same as those of kani or danekani with the difference that wall of sorus gets ruptured and black mass of powder is exposed which gives blackish appearance to the earheads. The period of its occurrence and the method of controlling it are the same as those of kani. Removal and destruction of affected earheads also helps to check the disease to some extent.

Tikkya: Tikkya piricularia oryzae is the paddy blast. This disease has assumed serious proportions in the district, especially in the heavy rainfall.tracts. When severe, it is reported to cause damage to the extent of 46 to 75 per cent. It attacks seedling between July and August and the grown-up crop between September and November. The disease appears on leaves, necks and nodes of ears. On leaves it manifests as spindle-shaped spots with grey-white centres and purple red margins. These spots gradually collapse and the leaves ultimately wither. The nodes and necks begin to, blacken when eartheads are affected and this results in sterility leaving the ears without grains. Infected seed areas and affected debris are the source of infection. The following schedule is recommended to control the disease: (1) treating the seed with organo mercurial seed-dresser containing one per cent organic mercury at the rate of one ounce to 11.325 kg (25 lbs.) of seed, (2) dipping seedings, before they are transplanted, in Bordeaux mixture 3:3:50, (3) one or two sprayings of Bordeaux mixture 3:3:50 till flowering, any copper compound preferably copper oxychloride containing 50 per cent metallic copper could also be used for the purpose, (3) sowing blast resistant varieties.

Karpa: Karpa or Xanthomonas oryzae is a bacterial parasite occurring on paddy seedlings in July and on grown up crop between August and October. The loss caused by the parasite is estimated to be of the order of 10 to 20 per cent. The typical symptom of the disease is appearance of black angular lesions on leaves, drying of tips, margins and ultimately the entire leaf. The disease enhances as soon as new leaves and tillers are formed. The ears in general show dying appearance. Seeds from infected areas and affected debris are the source of infection. Spraying the crop every fortnight with copper compound having 50 per cent metallic copper is practised to control the disease.

Tambera or Haldya : Puccinia graminis trilici, locally known as tambera, haldya or gerwa is the stem rust of wheat. It is by far the most destructive disease of wheat and when it is severe, causes damage to the tune of 60 per cent to 75 per cent of the crop. The disease manifests itself in the form of reddish brown elongated linear eruptive spots known as postules mostly on stems and also on leaves, leaf sheaths and awns, etc., in the early part of the season. When these postules are rubbed by a thumb, a brownish red powder smears the thumb. The reddish brown powder contains spores called uredospores. Later in the season, these reddish brown postules change their colour and become black. These black postules contain blackish powder consisting of spores called toleutospores meaning last spores. As the name signifies, this stage appears when the crop is about to mature. On account of the black colour of the powder in the postules, the disease is also known as black stem rust. This is active during November and February. Spores carried by wind and rain constitute the main source of infection.

Kani or Kajali: Kani or Kajali, ustilago tritici is a loose smut of wheat. It affects the crop between January and March and causes damage to the extent of about five per cent. The disease appears when the ears turn blackish. Every part of the ear except the rachis and awns gets affected and a loose blackish powder is formed in place of grains. This blackish powder consists of the spores of the fungus. Infected seeds and the black mass of powder are blown by the wind to the adjacent fields when the crop is in flowering stage. This spreads the infection. The infection being inside the seed, dressing them with fungicides is ineffective and hence a special method is evolved which is as under:

The seeds are soaked in cold water from 8 a.m. to 12 noon sometime during the first fortnight of May. The seeds are then spread on galvanised iron sheets in hot sun for about four hours. The seeds are stirred occasionally. Subsequently the seeds are thoroughly dried in the shade and stored in the gunny bags. These gunny bags are dusted with insecticides like pyrethrum. D.D.T. and B.H.C. (Benzene hexachloride) powders.

Of Pulses.— Mar: Fusarium oxysporum, locally known as mar is the wild disease of tur. Its attack is generally of a mild nature, the extent of loss in yield being one to two per cent. The disease is soil borne. Affected plants appear sickly, their leaves drop down and they ultimately wither and die. If roots of affected plants are split open, they exhibit brown discoloration of vascular tissue. The disease is of seasonal occurrence and may break out any time during the growth of the crop the method of controlling the disease is to grow wilt resistant varieties.

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