The Gazetteers Department

There are various pests of crops. It is not always possible to estimate accurately the extent of damage done by these pests, as it depends upon the severity of infestation in any particular year. However, an attempt is made below to give a broad description of the pests and estimated damage done by them and to suggest remedial measures which can be adopted by the cultivators at the minimum cost, which include the use of insecticide, fungicide and rodenticides like gamaxene, gueserol, perenox, sulphur dust, zinc phosphides. These chemicals are available with local dealers and are also distributed by the Department of Agriculture at reasonable rates.

Of Cereals.

The main cereal crops of the district are paddy, nagli and vari. Following is the description of pests affecting them: -

Bhatache khodatil kid, the stem borer, (schoenobius incertellus wlk.):-The caterpillar bores into the stem of the paddy plant and causes death of central shoots. If boring is done at a late stage in the growth of plant, the plant bears only empty earheads. Damage can be recognised by the appearance of whitish shoots, then called dead-hearts. Annually the estimated area affected by this pest in the district is 2,000 acres. Since the pest hibernates in the stubbles, they should be collected and destroyed after the harvest of the crop. In the early stages of attack, the affected shoots and the caterpillars should be picked out and destroyed. As the eggs are generally found on the tips of the leaves of young plants ready for being transplanted, the tips of the leaves should be cut off before transplanting.

Lashkari alya, the swarming caterpillars (spodoptera mauritia B.), are active mostly during night time. Annually, about 500 acres under paddy are affected by this pest. In 1953-54, kharif paddy was seriously attacked by this pest. But owing to timely measures taken to combat it, a major portion of the crops could be saved. Another serious infestation experienced by the rabi crop in 1954, was mostly confined to Sawantwadi taluka. Crops over about 700 acres were damaged. However, owing to the efforts of the Department of Agriculture and co-operation on the part of the people, about 75 per cent of the crops were saved. Caterpillars are dark green with a slight yellow tinge. The pest can be controlled by (1) protecting the seed-beds by deep trenches. (2) collecting the egg masses by hand, (3) trapping the caterpillars under plants or small bunches of grass during day time. (4) ploughing the fields after harvest to expose the pupae, (5) flooding the affected patch and dislodging the caterpillars from the plants by means of a rope, (6) dusting in the evening, five per cent Benzene Hexachloride (BHC) at the rate of 20 lbs. to 30 lbs. per acre, (7) spraying about 60 gallons to 100 gallons per acre of 50 per cent. BHC (water dispersible) at the rate of 5 lbs. in 100 gallons of water.

Suralyantil ali, the rice case worm, (nymphula depunctalis G). The caterpillars cut the paddy leaves into short lengths, construct tubular cases, remain inside such rolls and feed on the foliage. The pest is controlled by (i) removal and destruction of tubular cases, (ii) rope dragging to dislodge the caterpillars after flooding the crops (a little quantity of crude oil is added to the fluid), (iii) dusting BHC at the rate of 15lbs. to 20 lbs. per acre, (iv) spraying one pound of pyrethrum in 60 gallons of water or seven to eight pounds of D. D. T. 50 per cent. (water dispersible) in 100 gallons of water.

Veet or nile bhungere, the blue beetle (Leptispa Pygmoea) is most active during July-September and hibernates in wild grasses during off season. All the stages of insect growth take place on the paddy plants itself. Annually about 5,000 acres are affected by this pest and the extent of the damage done varies between 10 per cent to 20 per cent of the affected area. The beetles are collected by hand and destroyed. They may be dislodged in water by dragging a thick rope across the flooded field. Dusting of five per cent BHC at the rate of 15 lbs. to 20 lbs. per acre may also be tried. Sometimes clipping of the tips of the seedlings before transplanting also proves useful.

Bhatavaril tol, the paddy grasshopper (hierglyphus banian Fb.): Both the nymphs and adults eat the foliage and also feed on the developing earheads of paddy. If the pest occurs every year, fields are ploughed after the harvest. Dusting infested fields with five per cent BHC at the rate of 20 lbs to 30 lbs. per acre may also be tried.

Khekade, crabs (paratelphusa Sp.) are active during June-November. They cut the paddy plants at the ground lexel, feed on them and cause breaches in the field embankments by burrowing. Fumigation of the burrows with Cynogas 'A' dust may be tried. Poison baits composed of one pound 50 per cent. DDT (water dispersible), boiled rice (nine pounds) and jaggery (six ounces) are also effective in controlling this pest. Other important crops which are affected by pests are cocoanut and mango,

Of Cocoanut.

Rhinoceros beetle (Oryetes rhinoceros) is indeed a serious pest of cocoanut. Annually, it affectes nearly fifty per cent of the area under this crop, though the extent of damage done varies between 20 per cent and 30 per cent of the area of infestation. The beetle bores into the tender part, biting the fibrous portion. The tree may begin to wither and ultimately die. The pest is controlled by treating the breeding places every two months with manure dumps or compost pits with 0.2 per cent. BHC (water dispersible) spray. The adult beetles are extracted from the fruit and killed by using a beetle rod. The beetle holes and the inner leaf-axils are filled with sand and five per cent BHC dust in equal parts.

Tadmadavaril sondya, the red palm weevil (rhychsphorus ferrun, gineus F.) is another destructive beetle. The grubs pass their life on the palm and tunnel through the soft tissues of trees. The pest is controlled by injections of Pyrocone E, i.e., Pyrothrives Pipenyi Butoxide combinations of one per cent into affected parts.

Of Mango.

Ambyavaril tudtude, jassid hoppers (idiocerus atkinsoni L., idiocerus nivcosparsus L., idiocerus clypealis L.) are a pest which cause damage to the flowers during flowering season. Nearly 50 per cent of the area is infested. The damage, however, varies between 20 per cent and 30 per cent. The nymphs and adults suck the sap of the tender leaves and flowers and thus reduce the bearing of fruit. They also secrete a sugary substance called honeydew permitting a sooty mould to develop. The pest is effectively controlled by the fortnightly application of five per cent. DDT sulphur dust.

Ambyavaril bhirud, the mango stem-borer (batocera rubus L.): The grubs bore and tunnel through the stem exuding masses of refuse. The branches may collapse and the tree may wither. An injection of borer solution (carbon disulphide two parts, chloroform one part and creosote one part) is recommended to control the pest; the hole is closed with mud after the injection is given.

Others.

Tambdya mungya or ombil, the red ants (Cecophylla smaragdina F.) do not feed on plants. They spread all over the tree and build nests of leaves. Generally, they are found on fruit trees. Not only they are a nuisance but they also protect noxious insects like aphids etc., for getting honey-dew from them. Dusting with five per cent DDT and sulphur (1:1) or five per cent BHC and sulphur (2:1) has been found effective.

Rats.

Undir, the rat (rathus rathus): In Ratnagiri district rats attack cocoanut trees and areca palms, besides being a nuisance in grain godowns and houses. Annually, about 20 per cent of the area under cocoanuts is reported to be affected by them. The percentage of damage in affected trees is nearly 30. In the fields, rats are destroyed by trapping and poison baiting (one part of zine phosphide mixed with 16 parts of wheat flour).

Wild Animals.

Wild animals: There are no details available about the damage done by wild animals like pigs, jackals and monkeys. It is reported that annually about five per cent of the area under the standing crops of paddy, nagli, etc., is affected. The extent of damage is of the order of 10 per cent of the affected area. Encouragement is given by the Development Board for killing these animals and for protecting crops. Cash prizes are awarded, viz., Rs. 10 for a tiger, Rs. 5 for a wild hog and Re. 1 for a monkey. In 1953-54, the Board distributed Rs. 1,588 for killing wild hogs at the rate of Rs. 2 per hog. There were 77 shikar sanghs (Gun Clubs) in the district [Kalyankari Rajyachi Watchal-Ratnagiri District-1957.].

DISEASES.

The following are the important plant diseases observed in Ratnagiri district

Of Cereals.

The important diseases which affect and cause extensive damage to paddy, rala and nagli in the district are karpa, udbatti (Ephelis Oryzae) Kani and Kevda (Xanthomonas sp.).

Karpa or the blast of rice (Piricularia Oryzae) is the most destructive of these. It is reported to have made its first appearance in an epidemic form in 1946 in the southern districts of the former Bombay State. Damage due to this disease has not been assessed, but it is estimated to be in the neighbourhood of 15 per cent to 20 per cent of the total crop production. As yet no permanent method of control has been devised; seed treatment and spraying with Bordeaux mixture in the proportion of 3: 3: 50 has been recommended as a temporary control measure. However, the work of evolving blast resistant varieties is in progress.

Kani or smut of rala (sphecelothica sp.): The damage caused by kani is sometimes very heavy, ranging between 20 per cent and 30 per cent of the crop. The occurrence of this disease can be totally obviated by steeping the seed in two per cent copper sulphate solution, for 10 minutes. New-a-days, however, the seed with 200-300 mesh fine sulphur (four Ozs. of sulphur for 60 lbs. of seed) is more in vogue.

Kani and karpa of nagli: Of these two diseases, kani causes appreciable damage, which can be easily prevented by treating the seed with sulphur before sowing.

Of Pulses.

Mar, the wilt disease of gram (Fusarium Oxysporium) causes extensive damage and has not been amenable to any direct control measure so far. Plants dry up generally at the flowering stage or a little later. Resistant varieties like Nagpur 352 and Dohad are being evolved to meet the situation.

Of Vegetables.

Bhuri, the powdery mildew, (Erysiphe Polygoni) on cucurbit is universal. It can be controlled by dusting sulphur.

Kevda, the yellow vein mosaic of bhendi (Virus): This is a virus disease and affects both rabi and kharif crops. It is a highly infectious disease transmitted by white flies and may cause damage to the extent of 40 per cent to 100 per cent of the total crop. Mosaic can be avoided by systematic rogueing and destruction of all affected plants. Virus can be checked by not sowing bhendi during the 'close period', i.e. April-May. Breeding disease resistant types of bhendi is the only reliable method of controlling this disease and some work in this direction is in progress.

Mar and Tikka, (Verticillium dahliae; Cercospora sp.): These are common diseases on brinjal. Tikka can be controlled by spraying Bordeaux mixture in the proportion of 3: 3: 50. Mar, however, cannot be controlled by any direct control method except growing of resistant varieties.

Pane valne, leaf-curl of tomato (Virus): It is a very serious virus disease transmitted by white flies. No control methods have been devised as yet.

Of Areca-nut.

Koleroga of areca-nut is a very serious disease of areca-nut and is found to be prevalent in Guhagar, Dapoli, Chiplun, Sawantwadi and Vengurla talukas. It is caused by the fungus (phytophthora arecae). This disease attacks the ripening nuts in bunches and causes shedding. Dropping of immature nuts in large numbers takes place in the month of June. Later, the fallen nuts rot. The overall damage is estimated to vary between 15 per cent and 25 per cent of the crop. The following schedule is suggested by the Department of Agriculture for controlling the disease:-

(1) Removal and destruction of dead and dying tree tops.

(2) Application of Bordeaux mixture in the proportion of 5: 5: 50 to the bunches before the onset of the monsoon with particular emphasis on trees located in the vicinity of dead and dying trees of the previous season.

(3) The bunches should be tied with grass hoods previously soaked in Bordeaux mixture.

(4) Vigilance over the garden and immediate spraying of the bunches which may show dropping towards the end of August or September. The trees surrounding these foci of infection should also receive spraying.

Band disease of areca-nut is attributed to physiological causes and its occurrence is observed predominantly in Mandangad and Dapoli talukas. The estimated damage ranges between 35 per cent and 40 per cent of the total crop. No control measures have been devised as yet.

Mool-kujne or Anaberoga, the foot rot of areca-nut (ganoderma lucidum): This disease, of late, is reported to occur in serious proportions. The affected plants die within one to two weeks after the onset of the disease; recovery is almost impossible. Preventive measures such as cutting down the affected plants and burning down the remains form an important part of the schedule to control the disease.

Of Mango.

Bhuri, the powdery mildew of mango, (oidium magniterde) blossoms and results in poor setting of fruits. If young fruits are attacked they wither and drop down. Bhuri is usually accompanied by jassid hoppers, an insect pest, which jointly cause serious damage. However, both of them can be effectively controlled by dusting the blossoms with a mixture of 200 mesh-fine sulphur and five per cent D.D.T. dust in the proportion 1:1 or 1:2 depending upon the severity of jassid attack. First dusting is given when the blossom is complete; second application is made after fifteen days. Usually two dustings are adequate but sometimes a third may be necessary. The approximate cost of dusting works out to Rs. 2 per tree.

Bandgul, the loranthus of mango is a flowering parasite which attacks branches of mango trees by sending haustoria inside the tissues to derive nutrition. Affected branches do not thrive well and yield poorly. This parasite spreads from tree to tree through its seeds; the fruits which are red and have sweet sticky seeds are eaten by birds. If, by chance, these are deposited on mango branches, the seed germinates and a new plant of loranthus comes up. The only means of effective control is to cut down the parasite below the point of attachment with mango branch.

Of Cocoanut.

Shenda kujne, the bud rot disease of cocoanut, (phytophthora) often causes severe damage to the cocoanut cultivation in the district. The leaves drop off; the terminal bud rots and ultimately the plant is killed. The disease can be controlled as follows. If only outer sheaths are affected, these may be removed and the crown sprayed with one per cent Bordeaux mixture. If the disease has advanced much and there is no possibility of recovery, the entire crown may be cut down and burnt. As a prophylactic measure, the trees surrounding the diseased one should be sprayed with one per cent Bordeaux mixture. Cheek vahane, the stem bleeding disease of cocoanut is also very common, though the extent of damage depends upon the age of the palm and the conditions under which it is grown. Young plants can be killed by the disease though such cases are rare. The control measures recommended are as follows:-

The infected tissue should be chiselled out so that no diseased tissue is left. The cut surface should be painted with coal tar or Bordeaux paste.

Of Other Fruits.

Mar, Panama disease of banana, (Fusarium oxysporum) is a serious disease of banana and the Son variety is highly susceptible to it. The only way to combat this disease is to grow the wilt resistant Basrai variety.

Kevda, the chlorosis of banana, (Virus) is caused by a virus. Affected plants remain stunted and show somewhat bushy appearance. Severely diseased plants fail to yield fruit while in other cases the fruit is of poor quality. The disease is transmitted by a specie of aphids. The only successful way to combat this disease is to (i) burn all affected plants in the garden so as to prevent the disease from spreading; (ii) to prevent export of diseased suckers to other places and (iii) to plant disease-free suckers obtained from a healthy garden.

Khaira, the guava canker (Pestalotia Fisidil) affects fruits, which remain small and stunted and become unmarketable due to the appearance of cankers. Spraying with Bordeaux mixture 3: 3:50 when fruits are young, affords some protection.

Kevda, the mosaic of papaya (Virus) is caused by a virus. The papaya mosaic is transmitted by five different species of aphids. Due to its rapid spread and severity, papaya cultivation is threatened with extermination in the State. The only feasible method to control this disease is to observe a 'closed season,' by not growing papaya in a locality for a year in order to make the locality virus free; and to be successful, this has to be done on a community basis. Infected plants as and when they appear should be destroyed immediately.

Paya kujne, the foot-rot of papaya (Pythium Aphanidermatium) is serious only during the rainy season and affects such gardens as are liable to be water-logged or ill-drained. The disease is caused by a fungus parasite. Control measures take the form of preventive practices like prevention of water-logging and destruction of affected plants.

Khaira, the canker of kagdi lemon (Xanthomonas citri) is a bacterial disease of common occurrence in lemon. Generally, all the surface parts are affected by this disease which disfigures and, therefore reduces the market value of the fruit. Lemon canker cannot be controlled completely, although its severity can be minimized to some extent by the following treatment: (i) cut down and burn all affected stems, twigs and leaves, as far as possible in the month of May and (ii) give a thorough spraying of Bordeaux mixture 3:3: 50.

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