• Produces leaf spots, blossom blight, wither tip, twigs blight and fruit rot.
• Small blister like spots develop on the leaves and twigs. Young leaves  wither  and dry  Tender twigs wither and die back  symptom appears.
• Affected branches ultimately dry up. Black spots appear on fruits.
• The fruit pulp becomes hard, crack and decay at ripening. Infected fruits drop

• on dried leaves, defoliated branches mummified flowers and flower brackets.
• Contact with diseased fruit during transport and storage. The secondary spread is through  airborne conidia

• Temperature of 25°C and Relative Humidity 95-97%

• Before storage, treat with hot water, (50-55°C) for 15 minutes

•  Three types of symptoms: bunchy top phase, floral malformation and vegetative malformation.
• In bunchy top phase in nursery bunch of thickened small shoots, bearing small rudimentary leaves.  Shoots remain short and stunted giving a bunchy top appearance.
• In vegetative malformation, excessive vegetative branches of limited growth in seedlings.  They are swollen with short internodes forming a bunches of various size and the top of the seedlings shows bunchy top appearance.
• In malformation of inflorescens, shows variation in the panicle.  Malformed  head dries up in black massesa  and persist for long time.
• Secondary branches are transformed into number of small leaves giving a witches broome appearance.

1. Diseased propagatives materials.

• Diseased plants should be destroyed
• Use of disease free planting material
• Pruning of diseased parts along the basal 15-20 cm apparently healthy portions.

• Brown spots develop on the margin and at the tip of the leaf lamina.  They increase in size and become dark brown. Black dots appear on the spots which are acervali of the fungus.

• Survive on mango leaves for over a year. Spreads through wind borne conidia.

• Heavy infection is noticed during the monsoon when the temperature is 20-25oC.and high humidity.

• Remove and destroy infected plant parts.

• The fungi produce mycelium which is superficial and dank.They row on  sugary secretions of the plant hoppers.  Black encrustation is formed which affect the photosynthetic activity.

• The fungus grows on the leaf surface on the sugary substances secreted by Jassids,Aphids and scale insects.

• Management should be done for insects and sooty moulds simultaneously. 
• Starch dries and forms a flake which are removed along with the fungus.

• First symptoms are dark staining of bark which progresses into the wood.
• Bark at the base is destroyed resulting in girdling and finally death of the tree.
• Bark in such parts dries, shrinks and cracks and shreds in lengthwise vertical strips.
• Later profuse exudation of gum from the bark of the trunk.
• Infection extends to crown roots.

• Prolonged contact of trunk with water as in flood irrigation; water logged areas and heavy soils.

• Soil inhabitants.
• Sporangia spread by splashing rain water, irrigation water and wind.
• Irrigation water and wind.

• Injuries to crown roots or base of stem during cultural operations should be avoided.

• If lesion has girdled less than ½ the girth, remove the diseased bark with a knife along with ½” of uninvaded bark.

• Acid lime, lemon and grapefruit are affected. Rare on sweet oranges and mandarins.
• Affects leaf, twig and fruits. In canker, leaves are not distorted.
• Lesions are typically circular with yellow coloured; appear on both sides of leaf, severe in acid lime (difference from scab) When lesions are produced on twigs, they are girdled and die.
• On fruits, canker lesions reduce market value.

• Free moisture for 20 minutes, 20-30°C.

• Wind and rain splashes.
• Survives in infected leaves for 6 months.
• Injury caused by leaf miner helps the entry of the bacterium.

• Control leaf miner when young flush is produced.
• Prune badly infected twigs before the onset of monsoon.

• Lime is susceptible both as seedling or buddling on any root stock.
• But mandarin and sweet orange seedlings or on rough lemon, trifoliate orange, citrange; Rangpur lime root stocks tolerant; susceptible root stocks are grapefruit and sour orange.
• In sweet orange or mandarin on susceptible root stocks, leaves develop deficiency symptoms and absise.
• Roots decay, twigs die back. Fruit set diminishes; only skeleton remains.
• Fine pitting of inner face of bark of sour orange stock.
• Grapefruit and acid lime are susceptible irrespective of root stock.
• Tree stunted and dies yield very much reduced. Fruits are small in size.

• Use of infected bud wood Toxoptera citricida (aphid) is the important vector.

• For sweet orange and mandarin. Avoid susceptible root stocks.
• For acid lime, use seedling preimmunised with mild strain of tristeza.

• This disease affects almost all citrus varieties irrespective of root stock.
• Stunting of leaf, sparse foliation, twig die back, poor crop of predominantly greened, worthless fruits.
• Sometimes only a portion of tree is affected.A diversity of foliar chlorosis.
• A type of mottling resembling zinc deficiency often predominates.
• Young leaves appear normal but soon assume on outright position, become leathery and develop prominant veins and dull olive green colour. Green circular dots on leaves.
• Many twigs become upright and produce smaller leaves.
• Fruits small, lopsided with curved columella. The side exposed to direct sunlight develops full orange colour but the other side remain dull olive green.
• Low in juice and soluble solids, high in acid. Worthless either as fresh fruit or for processing. Seeds poorly developed, dark coloured, aborted.

• Infected budwood; psyllid vector-Diaphorina citri

• Control psyllids with insecticides.
• Use pathogen free bud wood for propagation.

• Symptoms of this disease are observed on mature fruits on the tree.
• The characteristic symptoms consist of sunken, dark colored, necrotic lesions. Under humid conditions, the necrotic lesions become covered with pinkish spore masses.
• As the disease progresses, the small sunken lesions coalesce to form large necrotic patches affecting the flesh of the   fruit

• Control measures are needed in commercial guava production.
• The use of resistant cultivars provides the most efficient tactic in disease management.

• The pathogen can affect foliage, young shoots, inflorescences and fruit of guava.
• Typical symptoms associated with this disease include distortion, defoliation, reduced growth and if severe, mortality.
• On fully expanded leaves, dark bordered, roughly circular brown lesions with yellow halos develop

• Control of guava rust is based on the use of fungicides.
• Scouting fields for onset of disease or during the times of year when environmental conditions are favorable for pathogen infection are recommended so that proper and timely fungicide applications can be made.
• In addition, proper cultural tactics such as proper fertilization, irrigation, pruning and sanitation aide in achieving a healthy, vigorously growing tree less vulnerable to disease pressures.

• Disease symptoms are exhibited on both abaxial and adaxial leaf surfaces as orange, rust-colored, dense silky tufts ranging from 5 to 8 mm in diameter.
• Upon scraping away these spots, a thin, grayish white to dark-colored, necrotic crust remains on the leaf.
• These spots usually come together to form large irregular patches on a leaf. As the spots mature they take on a dull, grayish green color.
• Twigs and branches are also affected causing the bark to crack due to the growth and expansion of the pathogens filaments into the cortical tissues of the host.

• Algal leaf spot can be reduced by maintaining tree vigor with cultural techniques such as proper fertilization and irrigation, proper pruning to enhance air circulation within the canopy and sunlight penetration, managing weeds and wider tree spacing. Managing insect, mite and other foliar diseases increases tree vigor and lessens susceptibility to this disease.

• Symptom appears on leaves and fruits.
• On lower side of the leaf lesion appear as olivaceous spots   which turn dark brown to black and become velvety.
• On young foliage, the spots have a radiating appearance with a feathery edge.
• On older leaves the lesions are more definite in outline.
• The lesion may form a convex surface with corresponding concave area on the opposite side.
•  In severe infection leaf blade curved, dwarfed and distorted.
• Fruits show small, rough, black circular lesions.
• The centre of the spots become corky and on mature fruits, yellow halo is  seen around the lesions.

• Primary spread through ascospores and secondary spread by air borne conidia.
• Favourable conditim
• Cool and moist conditions due to rain or show at higher elevation and shady portion.

• The initial symptom usually occurs on flowers, which become water soaked, then shrivel turn brownish to black in colour and fall or remain hanging in tree.
• The symptom spread to leaves twigs. Terminal twigs wilt from hip to downward and also spread to branches fruits becomes water soaked, turns brown, shrivels and findly becomes black.
• Oozing may be seen in the affected area.

• The bacterium survives in infected branches and twigs. Secondary spread by insects and rain splash.

• Temperature above 24ºC and heavy rain.

• Removal and destruction of affected parts.
• cutting of blighted twigs and root sprouts in summer

• Young spots starts from stem end of the fruit as light brown watery rot. As the fruit ripens  area of the rotting increases,
• skin becomes wrinkled.
• A peculiar musty odour is emitted
• Under humid condition a bluish green sprorulating growth appears.

• Infection take place by wounds in the skin caused by insects and during handing in storage and transport.

• Careful handling of fruits without causing any wounds.

• This is one of the worst diseases of tomato occurring in the nursery.
• Damping off of tomato occurs in two stages, i.e. the pre-emergence and the post-emergence phase.
• In the pre-emergence the phase the seedlings are killed just before they reach the soil surface.
• The young radical and the plumule are killed and there is complete rotting of the seedlings.
• The post-emergence phase is characterized by the infection of the young, juvenile tissues of the collar at the ground level.
• The infected tissues become soft and water soaked. The seedlings topple over or collapse.

• Seed treatment with fungal culture Trichoderma viride (4 g/kg of seed)

• This is a common disease of tomato occurring on the foliage at any stage of the growth.
• The fungus attacks the foliage causing characteristic leaf spots and blight. Early blight is first observed on the plants as small, black lesions mostly on the older foliage.
• Spots enlarge, and by the time they are one-fourth inch in diameter or larger, concentric rings in a bull's eye pattern can be seen in the center of the diseased area.
• Tissue surrounding the spots may turn yellow. If high temperature and humidity occur at this time, much of the foliage is killed.
• Lesions on the stems are similar to those on leaves, sometimes girdling the plant if they occur near the soil line.
• Transplants showing infection by the late blight fungus often die when set in the field. The fungus also infects the fruit, generally through the calyx or stem attachment.

• Removal and destruction of the affected plant parts. Practicing crop rotation helps to minimize the disease incidence.

• This is one of the worst diseases of tomato occurring mostly in the nurseries. The first symptoms of the disease are clearing of the veinlets and chlorosis of the leaves.
• The younger leaves may die in succession and the entire may wilt and die in a course of few days. Soon the petiole and the leaves droop and wilt.
• In young plants, symptom consists of clearing of veinlet and dropping of petioles. In field, yellowing of the lower leaves first and affected leaflets wilt and die.
• The symptoms continue in subsequent leaves. At later stage, browning of vascular system occurs. Plants become stunted and die.

• The nursery should be regularly inspected for wilt infected plants.
• The affected plants should be removed and destroyed.
• Prior to planting the beds should be drenched with Carbendazim (0.1%) and the seeds should be treated with the Thiram (2.5 kg/ha).
• Crop rotation with a non-host crop such as cereals helps to reduce the disease inoculum.

• The plant may be attacked at any stage of its growth. The disease is characterized by numerous, small, grey, circular leaf spots having dark border.

• Removal and destruction of the affected plant parts.

• This is one of the most serious diseases of tomato crop. Relatively high soil moisture and soil temperature favour disease development.
• Characteristic symptoms of bacterial wilt are the rapid and complete wilting of normal grown up plants.
• Lower leaves may drop before wilting. Pathogen is mostly confined to vascular region; in advantage cases, it may invade the cortex and pith and cause yellowbrown discolouration of tissues.
• Infected plant parts when cut and immersed in clear water, a white streak of bacterial ooze is seen coming out from cut ends.

• Crop rotations, viz., cowpea-maize-cabbage, okra-cowpea-maize, maize- cowpea-maize and finger millet-egg plant are reported effective in reducing bacterial wilt of tomato.
• Seedling treatment with Streptocycline (1 g/40 litres of water) for 30 min protects the seedlings in the initial stages of growth.

• Moist weather and splattering rains are conducive to disease development. Most outbreaks of the disease can be traced back to heavy rainstorms that occur in the area.
• Infected leaves show small, brown, water soaked, circular spots surrounded with yellowish halo.
• On older plants the leaflet infection is mostly on older leaves and may cause serious defoliation.
• The most striking symptoms are on the green fruit. Small, water-soaked spots first appear which later become raised and enlarge until they are one-eighth to one-fourth inch in diameter.
• Centers of these lesions become irregular, light brown and slightly sunken with a rough, scabby surface.
• Ripe fruits are not susceptible to the disease. Surface of the seed becomes contaminated with the bacteria, remaining on the seed surface for some time.
• The organism survives in alternatehosts, on volunteer tomato plants and on infected plant debris.

• Bacterial spot is difficult to control once it appears inthe field.
• Disease-free seed and seedlings should always be used and the crop should be rotated with non-host crops so as to avoid last years crop residue.
• Spraying with Agrimycin-100 (100 ppm) thrice at 10 days intervals effectively controls the disease.

• The disease is characterized by light and day green mottling on the leaves often accompanied by wilting of young leaves in sunny days when plants first become infected.
• The leaflets of affected leaves are usually distorted, puckered and smaller than normal. Sometimes the leaflets become indented resulting in "fern leaf" symptoms.
• The affected plant appears stunted, pale green and spindly.
• The virus is spread by contact with clothes, hand of working labour, touching of infected plants with healthy ones, plant debris and implements.

• Seeds from disease free healthy plants should be selected for sowing. The seeds should be thoroughly rinsed and dried in shade.
• In the nursery all the infected plants should be removed carefully and destroyed. Seedlings with infected with the viral disease should not be used for transplanting.
• Crop rotation with crops other than tobacco, potato, chilli, capsicum, brinjal, etc. should be undertaken.

• This disease is transmitted by whitefly (Bemisia tabaci). It is one of the most devastating diseases of tomato.
• Leaf curl disease is characterized by severe stunting of the plants with downward rolling and crinkling of the leaves. The newly emerging leaves exhibit slight yellow colouration and later they also show curling symptoms.
• Older leaves become leathery and brittle. The nodes and internodes are significantly reduced in size.
• The infected plants look pale and produce more lateral branches giving a bushy appearance. The infected plants remain stunted.

• The affected plants should be removed and destroyed. Alternate or collateral hosts harboring the virus causing this disease is removed at the time of weeding or earthing up operations to minimize the spread of the disease.
• Checking the white fly population can reduce the disease incidence.

• The spotted wilt virus is transmitted through thrips (Thrips tabaci, Frankliniella schultzi and F. occidentalis).
• This disease is similar to streak in that it causes streaking of the leaves, stems and fruits. Numerous small, dark, circular spots appear on younger leaves.
• Leaves may have a bronzed appearance and later turn dark brown and wither.
• Fruits show numerous spots about one-half inch in diameter withconcentric, circular markings. On ripe fruit, these markings are alternate bands of red and yellow.

• The affected plants should be removed and destroyed.
• Alternate or collateral hosts harboring the virus causing this disease is removed at the time of weeding or earthing up operations to minimize the spread of the disease.

Diseases of Brinjal

Bacterial Wilt (Pseudomonas solanacearum)
Symptoms

• Bacterial wilt symptoms on leaf surface Wilting, stunting, yellowing of the foliage and finally collapse of the entire plant are the characteristic symptoms of the disease.
• Lower leaves may droop first before wilting occurs.
• The vascular system becomes brown.
• Bacterial ooze comes out from the affected parts.
• Plant show wilting symptoms at noontime will recover at nights, but die soon.

Control

• Pant samrat variety is tolerant.
• Crop rotation with cruciferous vegetables such as cauliflower help in reducing the disease incidence.
• Fields should be kept clean and effected parts are to be collected and burnt.
• The disease is more prevalent in the presence of root knot Nematodes, so control of these nematodes will suppress the disease spread.

Cercospora Leaf Spot (Cercospora solani -melongenae, C. Solani)
Symptoms     
Leaf spot symptoms 

• The leaf spots are characterized by chlorotic lesions, angular to irregular in shape, later turn grayish-brown with profuse sporulation at the centre of the spot.
• Severely infected leaves drop off prematurely, resulting in reduced fruit yield.

Control

• Pant Samrat variety is resistant to both the leaf spots.
• Diseases can be managed by growing resistant varieties.

Tobacco mosaic virus (TMV)
Symptoms

• Mosaic mottling of leaves and stunting of plants are the characteristic symptoms of potato virus Y Mosaic symptoms are mild in early stages but later become severe.

• Infected leaves are deformed, small and leathery. Very few fruits are produced on infected plants.
• The important symptom produced by tobacco mosaic virus is conspicuous mottling of leaves.
• Leaves also develop blisters in advanced cases. Severely infected leaves become small and misshapen. Plants infected early remain stunted.
• PVY is easily sap transmitted.
• It is transmitted in the field through aphids, Aphis gossypii and Myzus persicae and perpetuates on weed hosts like Solanum nigrum and S.xanthocarpum.
• TMV is transmitted by sap, contaminated implements and clothes, soil debris and hands of labour.
• It can perpetuate on many cultivated plants like cucurbits, legumes, pepper, tobacco, tomato and weed hosts. The virus survives in plant debris in soil.

Control

• Destroy all weeds and avoid planting cucumber, pepper, tobacco, tomato near brinjal seed beds and field.
• Wash hands with soap and water before working in seed beds.
• Prohibit smoking or chewing of tobacco who are handling brinjal seedlings.
• .

Collar Rot (Sclerotium rolfsii)

• The disease occasionally occurs in serious form.

Symptoms

• The lower portion of the stem is affected from the soil borne inoculum (sclerotia).
• Decortication is the main symptom.
• Exposure and necrosis of underlying tissues may lead to collapse of the plant.
• Near the ground surface on the stem may be seen the mycelia and sclerotia.
• Lack of plant vigour, accumulation of water around the stem, and mechanical injuries help in development of this disease.

Control

• Seed treatment with 4 g of Trichoderma viride formulation per kg seed will help in reducing the disease.
• Collection and destruction of diseased parts and portions of the plant.

• The infection starts at the collar region of the pseudostems and progresses upwards as well as downwards. The collar region of the affected pseudostem becomes water soaked and the rotting spreads to the rhizome resulting in soft rot.
• At a later stage root infection is also noticed.
• Foliar symptoms appear as light yellowing of the tips of lower leaves which gradually spreads to the leaf blades.
• In early stages of the disease, the middle portion of the leaves remain green while the margins become yellow. The yellowing spreads to all leaves of the plant from the lower region upwards and is followed by drooping, withering and drying of pseudostems.

• Cultural practices such as selection of well drained soils for planting is important for managing the disease, since stagnation of water predisposes the plant to infection.
• Seed rhizomes are to be selected from disease free gardens, since the disease is also seed borne.
• Application of Trichoderma harzionum along with neem cake @ 1kg/bed helps in preventing the disease.

• Collection and burning of fallen leaves.

• Drying of twigs from tip down wards.
• Blackening of the twigs.
• The disease spreads to root and causes complete killing of the plants.

1. Collection and burning of fallen leaves.

• The growth of the fungus on the leaves appears as powdery coating. Infected leaves turn yellow and dry out.
• Infected plants remains stunted and fail to flower.

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