Tag: disease management

• Grapes (Vitis vinifera) are a major fruit crop grown globally for fresh consumption, raisins, and wine.
• Optimal growth requires balanced nutrition, pest and disease management, and proper cultural practices.
• Understanding disorders and their management is crucial for high yield and quality.

• Common deficiencies: Nitrogen, Potassium, Magnesium, Zinc, Boron, Iron.
• Symptoms include chlorosis, poor fruit set, stunted growth, and leaf necrosis.
• Soil and leaf analysis help diagnose nutrient disorders.

• Apply recommended fertilizers based on soil and tissue analysis.
• Use foliar sprays for micronutrient deficiencies (e.g., ZnSO4 for zinc, Fe-EDTA for iron).
• Incorporate organic manures and green manures to improve soil health.
• Maintain proper irrigation to aid nutrient uptake.

• Gibberellic acid (GA3) used to increase berry size and improve cluster looseness.
• Apply 25 ppm GA3 at calyptra fall and pepper stages for seedless varieties.
• Potassium chloride (0.2%) sprayed at 20 and 40 days after berry set for uniform ripening.

• Berry cracking: Caused by irregular watering or boron deficiency.
• Uneven ripening: Linked to potassium deficiency or hormonal imbalance.
• Poor fruit set: Often due to zinc or boron deficiency.

• Apply carbofuran 60 g/vine one week before pruning; irrigate well.
• Use neem cake 200 g/vine and Pseudomonas fluorescens for biocontrol.

Flea Beetles

• Spray phosalone 2 ml/l after pruning; repeat 2–3 times as needed.

Thrips

• Spray dimethoate 2 ml/l for control.

Mealy Bug

• Spray monocrotophos 2 ml/l; use sticky bands and natural predators for IPM.

• Caused by Uncinula necator.
• Symptoms: White powdery growth on leaves, shoots, and berries.
• Management: Sulphur dusting @ 6–12 kg/ha; use resistant varieties.

Downy Mildew

• Caused by Plasmopara viticola.
• Symptoms: Yellowish oil spots on leaves, white downy growth on lower surface.
• Management: Spray 1% Bordeaux mixture; ensure good air circulation.

• Harvest only after full ripening for best quality.
• Heat requirement: 2900–3600 degree days for most varieties.
• Average yields: Seedless – 15 t/ha/yr; Muscat – 30 t/ha/yr; Pachadraksha – 40 t/ha/yr; Anab-e-Shahi/Arka hybrids – 20 t/ha/yr.
• Room temperature storage: Up to 7 days; cold storage (-2 to -1.5°C): 40–45 days.

• Raisins are a major by-product in grape-growing regions.
• Grapes with 17° Brix and above are suitable; 20–23° Brix is standard for high-quality raisins.
• Proper drying and storage are essential to prevent spoilage.

• Botanical name: Solanum lycopersicum
• Family: Solanaceae
• Chromosome number: 2n=24
• Origin: Peru, Ecuador, Bolivia; domesticated in Mexico
• Edible part: Whole fruit (fleshy berry)
• Pollination: Mainly self-pollinated, hermaphrodite flowers

• First recorded in 1554, South America
• Spread from Mexico to Europe and Asia
• Introduced to India in 1828 by British
• Probable ancestor: Solanum lycopersicum var. cerasiformae (cherry tomato)
• Father of tomato research: Dr. C. M. Rick

• Global area: ~5.16 million ha; production: ~186 million tonnes (2023)
• Top producers: China, India, Turkey, USA, Egypt
• India: 0.88 million ha; 21 million tonnes; productivity: 23.8 t/ha
• Major Indian states: Madhya Pradesh, Karnataka, Andhra Pradesh, Odisha, Gujarat
• Export hubs: Pune, Bangalore, Nasik, Amaravati

• Second most important vegetable globally after potato
• Rich in ascorbic acid (31 mg/100g), lycopene, carotenoids
• Used fresh and processed (soup, sauce, ketchup, puree, paste)
• Health benefits: antioxidant, anticancer, digestive aid
• Tomato seed oil content: ~24%

• Annual herb with tap root system (depth >50 cm)
• Stem: erect, solid, hairy, glandular; height 2–4 m
• Leaves: compound, pinnatifid, irregularly toothed
• Flowers: small, yellow, borne in raceme cymes
• Fruit: fleshy berry, 2–15 cm diameter, color varies (green, yellow, red)
• Seeds: numerous, kidney-shaped, hairy

• By growth habit: Determinate (bushy, self-topping, early), Indeterminate (erect, late, needs staking)
• By fruit shape: Round, cherry, pear, oblate, etc.
• By subgenus (Muller, 1940): Eulycopersicon (red, self-compatible), Eriolycopersicon (green, wild, self-incompatible)

• Selection criteria: yield, disease resistance, fruit quality, shelf life
• IARI: Pusa Rohini, Pusa Ruby, Pusa Sadabahar, Pusa Uphar
• IIHR: Arka Vikas, Arka Abha, Arka Rakshak (disease resistant)
• IIVR: Kashi Amrit, Kashi Hemant, Kashi Aman (ToLCV resistant)
• Hybrids: Pusa Hybrid 1, Arka Vardan, Arka Meghali
• Processing: Punjab Chhuhara, Roma, Pusa Gaurav
• Protected cultivation: Indeterminate types (e.g., Pusa Ruby, Arka Abha)

• Warm season, day-neutral crop
• Optimum temperature: 20–24°C (growth), 15–20°C (fruit set)
• Red color (lycopene) best at 21–24°C; reduced above 27°C
• Soil: well-drained sandy loam to clay loam, pH 6.0–7.0
• Moderately tolerant to acid soils (pH 5.5)

• Raised beds (15 cm), 3 m x 1 m, sandy loam with organic matter
• Seed rate: OPV 400–500 g/ha; Hybrid 125–175 g/ha
• Seed treatment: Captan/Thiram 2 g/kg
• Bed drenching: Captan or copper oxychloride
• Harden seedlings by reducing water before transplanting
• Transplant 25–30 day old seedlings with 5–6 true leaves

• Resistance to soil-borne diseases and pests
• Tolerance to abiotic stresses (drought, salinity, temperature)
• Increased yield and fruit quality

Examples:

• Brimato: Tomato scion on brinjal rootstock (bacterial wilt resistance)
• Pomato: Tomato scion on potato rootstock (dual harvest)

• Deep ploughing (20–30 cm), followed by harrowing for fine tilth
• Soil solarization (optional) for pest and disease control
• Spacing: Determinate 60 x 45 cm; Indeterminate 90 x 60 cm
• Transplanting: Kharif (July), Rabi (Oct–Nov), Summer (Feb–March)

• FYM: 350 q/ha; N:P:K for OPV: 120:80:100 kg/ha; Hybrid: 200:100:120 kg/ha
• Apply ½ N and all P, K, FYM at planting; rest N as top dressing
• Mulching (25 micron) increases yield by 45–50%
• Drip irrigation saves water (up to 42%) and increases yield (up to 60%)
• Water requirement: 60 L/kg (open field), 4–22 L/kg (greenhouse)

• Weeding: 2 hand hoeings + earthing up
• Pre-emergence herbicides: metribuzin, fluchloralin, pendimethalin
• Staking: improves yield and fruit quality in indeterminate types
• Training: single, two, or three stem systems
• Pruning: remove lateral suckers, maintain 2 stems, every 8–10 days

• Harvest at breaker or half-red stage; first harvest at 70–85 days after transplanting
• Grading by color, size, maturity (Super A, Super, Fancy, Commercial)
• Storage: 12–15°C, 85–90% RH; mature green: up to 30 days, ripe: 10 days
• Yield: OPV 200–350 q/ha; Hybrid 600–750 q/ha

• Causes: irregular irrigation, moisture stress, boron deficiency
• Control: regular irrigation, borax spray, resistant varieties

Blossom End Rot

• Caused by calcium deficiency
• Control: spray CaCl₂ 0.5%, balanced irrigation

Puffiness

• Causes: poor fertilization, high N, high temp
• Control: 4-CPA/CPPU spray, balanced nutrition

Sun Scald

• Due to fruit exposure; avoid excessive pruning in summer

Blotchy Ripening, Cat Face, Golden Flakes

• Due to nutrient imbalance, abnormal growth conditions

• Yellow sticky traps, Chrysoperla release, methyl demeton/dimethoate spray

Whitefly (Bemisia tabaci)

• Remove infected plants, sticky traps, carbofuran, dimethoate/malathion spray

Leaf Miner (Liriomyza trifolii)

• Destroy mined leaves, NSKE 5% spray

Pinworm (Tuta absoluta)

• Pheromone traps, healthy seedlings, neem/Flubendiamide/Indoxacarb spray

Fruit Borer (Helicoverpa armigera)

• Trap crops, pheromone traps, Trichogramma release, Bt spray

• Raised beds, seed treatment (Trichoderma/Thiram), copper oxychloride drench

Early Blight (Alternaria solani)

• Remove debris, crop rotation, Mancozeb spray

Late Blight (Phytophthora infestans)

• Remove infected plants, crop rotation, copper oxychloride/Bordeaux mixture

Fusarium Wilt (Fusarium oxysporum f.sp. lycopersici)

• Remove infected plants, Carbendazim drench, crop rotation

Bacterial Wilt (Ralstonia solanacearum)

• Crop rotation, resistant varieties (Arka Abha, Arka Rakshak)

Mosaic (TMV)

• Disease-free seed, crop rotation, trisodium phosphate seed soak, vector control

Leaf Curl (ToLCV)

• Sticky traps, barrier crops, Imidacloprid/Dimethoate spray

• Use high-yielding, disease-resistant varieties and hybrids
• Adopt proper nursery, land, and nutrient management
• Implement grafting and protected cultivation for stress-prone areas
• Practice regular irrigation, mulching, and weed control
• Monitor and manage pests and diseases using IPM
• Harvest and store fruits at optimal maturity and conditions

• Scientific name: Solanum lycopersicum
• Family: Solanaceae
• Originated in western South America; domesticated in Central America
• Chromosome number: 2n = 24 (corrected; not 26)
• India ranks 2nd globally in tomato production

• Botanically, tomato fruit is classified as a berry
• Rich in vitamins A, C, K and antioxidants like lycopene and lutein
• Consumption helps reduce risk of cancer, supports eye health, and regulates blood pressure

• Top producers: China, India, USA, Turkey, Egypt
• In India: Andhra Pradesh, Madhya Pradesh, Karnataka, Gujarat, Odisha, West Bengal, Chhattisgarh, Bihar, Telangana, Tamil Nadu, Uttar Pradesh, Maharashtra, Haryana, Himachal Pradesh

• Tomato is propagated by seeds or vegetative methods
• Vegetative propagation uses plant cuttings for true-to-type plants
• Seed propagation is most common in commercial cultivation

• Warm season crop; optimal temperature: 21–24°C
• Cannot tolerate frost or high humidity
• Prefers deep, well-drained sandy loam soils (15–20 cm depth)
• Requires low to moderate rainfall (approx. 194 mm during growing season)

• Land should be well-prepared, ridged, and free of weeds
• Seed sowing: June–July (autumn-winter), November (spring-summer), March–April (hills)
• Transplant seedlings at 75–90 x 45–60 cm spacing
• Use healthy seedlings (10–12 inches tall)

• Types: Cherry, Grape, Roma, Beefsteak, Heirloom, Tomatoes on the vine, Green tomatoes
• Popular varieties: Rashmi, Pusa Early Dwarf, Rupali, Sioux, Vaishali, Abhinav, Avishkar

• Requires 1–2 inches of water per week
• Drip irrigation preferred for transplanted tomatoes
• Sprinkler irrigation for direct-seeded crops (early stages)
• Furrow irrigation used after establishment

• Apply 20–25 t/ha well-rotted FYM/compost during land preparation
• Recommended fertilizer dose: 75:40:25 kg N:P2O5:K2O per ha
• Apply half N, full P, and half K as basal; remaining N and K as top dressing

• Practices: crop rotation, cultivation, sanitation, proper field preparation
• Pre-emergence herbicide: Metribuzin
• Post-emergence herbicide: Paraquat

• Circular lesions on fruit; centers turn tan; black spots on fruit

Management:

• Avoid sprinkler irrigation during fruit ripening
• Crop rotation with non-solanaceous crops

Black Mold Disease
Pathogen: Alternaria spp.
Symptoms:

• Black or brown lesions on ripe fruit surface

Management:

• Avoid wetting foliage; use fungicides if necessary

Colorado Potato Beetle
Nature: Insect pest
Symptoms:

• Feeding damage to foliage; black and yellow striped beetle visible

Management:

• Handpick adults and larvae; destroy in soapy water
• Use Bacillus thuringiensis for larvae control

Aphids
Nature: Insect pest
Symptoms:

• Yellowing and distortion of leaves

Management:

• Use tolerant varieties; apply neem oil

• First harvest: 60–70 days after transplanting (variety dependent)
• Harvest by twisting fruit by hand or mechanically
• Average yield: 20–25 t/ha; hybrids: up to 50–60 t/ha

• Store mature (yellow) tomatoes at 12–16°C (55–60°F)
• Cold storage life: 3–4 weeks
• Do not store below 4°C (40°F) to avoid chilling injury

• Okra (Abelmoschus esculentus) is affected by several fungal and viral diseases.
• Major diseases: Powdery mildew, Fusarium wilt, Alternaria leaf spot, Yellow vein mosaic.
• Effective management requires knowledge of pathogens, symptoms, and control measures.

• White or grayish powdery growth on upper leaf surfaces, later covering entire leaf.
• Lower leaf surfaces may also be infected.
• Affected leaves dry and fall prematurely, reducing yield.

Disease Cycle:

• Overwinters as dormant mycelium or cleistothecia on infected leaves.
• Secondary spread by wind-borne conidia.
• Favored by 60–80% relative humidity and dry conditions.

Management:

• Spray fungicides: wettable sulphur (0.25%), dinocap (0.1%), carbendazim (0.1%), hexaconazole (0.05%), or difenoconazole (0.05%).
• Repeat sprays at 10–14 day intervals.
• Biocontrol: Ampelomyces quisqualis, Trichoderma spp., Bacillus subtilis.
• Use azadirachtin (0.03% EC) as needed.

• Yellowing, stunting, wilting, and rolling of leaves.
• Dark brown vascular discoloration in stems.
• Severe cases: stem blackening and plant death.

Etiology:

• Produces hyaline mycelium, microconidia (single/two-celled), macroconidia (3–4 septa), and chlamydospores.

Disease Cycle:

• Survives as chlamydospores in soil and infected seeds.
• Optimum temperature for growth: 25°C; disease develops at 22–28°C.

Management:

• Use healthy, treated seed (carbendazim 0.2%).
• Practice crop rotation and soil solarization.
• Remove and destroy affected plants.
• Grow resistant varieties: CS-3232, CS-8899, IS-6653, IS-7194, Pusa Makhameli, Pusa Sawani.

• Brown leaf spots with pale margins and yellow halos.
• Lesions enlarge, show concentric rings, and coalesce.
• Severe infection causes leaf drying and defoliation.

Etiology:

• Produces cylindrical conidiophores and brown, muriform conidia with transverse and longitudinal septa.

Disease Cycle:

• Survives in infected plant debris, weed hosts, and seeds.
• Secondary spread by wind-borne conidia.

Management:

• Remove and destroy infected debris and weeds.
• Seed treatment with Thiram (6 g/kg).
• Spray Mancozeb (0.2%) after disease appearance.

• Vein yellowing and thickening, forming a network pattern.
• Leaves become chlorotic and yellow under severe infection.
• Plants are stunted with small, pale fruits.

Disease Cycle:

• Transmitted by whitefly (Bemisia tabaci) in a persistent manner.
• Wild and cultivated plants act as inoculum sources.
• Favored by dry, hot weather with low rainfall.

Management:

• Destroy wild hosts and avoid mixed cropping with pumpkin.
• Adjust sowing dates to avoid peak whitefly populations.
• Remove infected plants up to 55 days after sowing.
• Grow resistant cultivars: Punjab Padmini, Punjab-8, Prabhani Kranti, Hissar Unnat.
• Spray systemic insecticides (cypermethrin, deltamethrin, triazophos) to control vectors.

• Use disease-free, treated seeds and resistant varieties.
• Practice crop rotation, field sanitation, and timely removal of infected plants.
• Apply recommended fungicides and insecticides judiciously.
• Adopt biological control agents where feasible.
• Monitor fields regularly for early detection and management.

• Botanical name: Camellia sinensis
• Chromosome number: 2n = 30
• Origin: China
• Tea is susceptible to various fungal, algal, and oomycete diseases affecting yield and quality.
• Effective disease management is crucial for sustainable tea cultivation.

• Circular, raised, purple to reddish-brown lesions on leaves.
• Older spots become greenish-gray, resembling lichen.
• Most lesions develop on upper leaf surface; rarely harmful to plant vigor.

Disease Cycle:

• Alga produces rust-colored spore-like bodies on leaf spots.
• Dispersed by wind or rain; favored by high humidity and poor drainage.

Management:

• Avoid plant stress and poorly drained sites.
• Promote air circulation; prune and destroy infected parts.
• Apply Bordeaux mixture; improve soil nutrition (NPK).

• Small, oval, pale yellow-green spots on young leaves.
• Spots enlarge, turn brown/gray with concentric rings and black dots.
• Leads to defoliation; affects leaves of all ages.

Disease Cycle:

• Fungal spores in black dots on lesions.
• Spread by rain splash; infect new leaves under wet conditions.

Management:

• Avoid plant stress; ensure adequate spacing for air flow.
• Spray Copper Oxychloride or Bordeaux mixture (0.1%) in winter and summer.

• Pinhole-sized spots on young leaves (<1 month old).
• Spots enlarge, become transparent, then light brown.
• Blister-like symptoms with water-soaked zones; blisters turn white and velvety, then brown.
• Young stems may bend, break, or die.

Disease Cycle:

• Continuous cycle in wet conditions; spores dispersed by wind.
• Direct penetration of leaf tissue; symptoms in 10 days.

Management:

• Prune and destroy affected leaves and shoots.
• Spray Bordeaux mixture, Copper Oxychloride (0.1%), or triazole fungicides (e.g., hexaconazole).
• Apply fungicides at 5-day intervals during rainy season.

• Black, hair-like fungal threads on upper branches and twigs.
• Rapid leaf drop due to volatile substances produced by fungus.

Disease Cycle:

• Spread via extension of hair-like threads from infected to healthy twigs.

Management:

• Remove and destroy crop debris.
• Prune out infected or dead branches.

• Small, brown, irregular spots on flower petals.
• Whole flower turns brown and drops prematurely.

Disease Cycle:

• Emerges in early spring during high moisture periods.

Management:

• Remove infected flowers and crop debris.
• Apply soil drenches with suitable fungicides.

• Browning and drooping of leaves; shoots dry and die.
• Cankers form on branches; tip dieback.

Disease Cycle:

• Spores produced on dead branches; spread by rain splash.
• Entry through wounds; survives on pruned branches.

Management:

• Plant in well-drained, acidic soils.
• Remove diseased twigs below cankered areas; disinfect tools.
• Apply protective fungicides during wet weather.

• Originates from dead leaves above soil; spreads to roots.
• Star-like mycelium under bark; mycelium surrounds stem base.
• Swollen ring of tissue above dead patch.

Management:

• Remove and destroy infected plants.
• Practice clean cultivation; remove fallen leaves.
• Dig trenches around infected bushes to expose soil to sunlight.

• Sudden yellowing and wilting of leaves; branch tip dieback.
• Gray blotches and sunken cankers on bark and stem.
• Cankers girdle stem; upper parts lose vigor and die.

Comments:

• Fungus enters through wounds; symptoms worsen in hot, dry weather.

Management:

• Plant in well-drained, acidic soils.
• Remove diseased twigs below cankers; disinfect tools.
• Apply protective fungicides during wet periods.

• Yellowing leaves; poor growth; wilting; discolored roots; rapid plant death.

Comments:

• Favored by poorly drained, warm soils.

Management:

• Plant in well-drained soils; avoid waterlogging.
• Apply appropriate fungicides to protect plants.

• Yellowing foliage; wilting or sudden death of plant parts.
• Withered leaves remain attached; red discoloration of roots; whitish mycelium visible.

Comments:

• Spread by mycelial strands in soil.

Management:

• Remove infected bushes and adjacent symptomatic plants.
• Remove all living/dead roots and stumps; destroy by burning.
• Treat surrounding bushes to prevent spread.

• Apply Benomyl or Copper Oxychloride (0.01%).
• Use botanical extracts (e.g., Azadirachta, A. nilagirica) at 10% concentration.
• Apply biocontrol agents (Bacillus sp., Pseudomonas sp., Trichoderma viride).

• Use Bacillus megaterium as a plant growth promoter and biocontrol agent.
• Induces systemic resistance and reduces disease incidence.

• Apply antagonistic fungi (e.g., Aspergillus niger, Trichoderma atroviride, T. citrinoviride) as foliar sprays.
• Reduces symptom severity and disease index.

• Combine cultural, chemical, and biological control methods for sustainable management.
• Use resistant varieties where available.
• Maintain field hygiene: remove debris, prune infected parts, ensure proper spacing.
• Apply fungicides judiciously to avoid resistance.
• Promote beneficial microorganisms for biocontrol.

• Cabbage is susceptible to several economically important fungal diseases.
• Fungal pathogens affect yield and quality.
• Early identification and management are crucial for disease control.
• Integrated approaches are recommended for sustainable management.

• Pathogen: Rhizoctonia solani.
• Symptoms: Stem constriction at base, stunted growth, seedlings may break at ground level.
• Favored by mechanical injury and wet conditions.
• Management: Use certified disease-free transplants, avoid injury, ensure good drainage.

• Pathogen: Fusarium oxysporum f. sp. conglutinans.
• Symptoms: Leaf yellowing, wilting, stunted growth, twisted stems, unilateral midrib curvature.
• Soil-borne and persists for years.
• Management: Grow resistant varieties, crop rotation, use disease-free seed.

• Pathogen: Leptosphaeria maculans (Phoma lingam).
• Symptoms: Light brown stem lesions with purplish margins, black dots (pycnidia), cankering at base.
• Seed and residue-borne.
• Management: Use disease-free seed, hot water seed treatment, crop rotation, sanitation.

• Pathogen: Alternaria brassicae, A. brassicicola.
• Symptoms: Circular brown to black spots with concentric rings and yellow halos.
• Seedborne and airborne spread.
• Management: Remove crop debris, seed treatment, crop rotation, fungicide application.

• Pathogen: Plasmodiophora brassicae (plasmodiophoromycete, not true fungus).
• Symptoms: Root galls, wilting, stunted and yellow leaves, premature bolting.
• Favored by acidic, moist soils.
• Management: Use clean seedbeds, long crop rotations, lime soil to raise pH, resistant varieties.

• Pathogens: Fusarium spp., Pythium spp., Rhizoctonia solani.
• Symptoms: Seedling collapse, wet rot at stem base, missing or wilted seedlings.
• Favored by high moisture and poor drainage.
• Management: Use sterilized soil, raised beds, good drainage, biocontrol agents.

• Pathogen: Hyaloperonospora brassicae (formerly Peronospora parasitica).
• Symptoms: Yellow patches on upper leaf surface, white fluffy growth below, leaf drop, black spots on curds.
• Favored by cool, moist conditions.
• Management: Resistant varieties, crop rotation, debris removal, avoid leaf wetting, fungicides.

• Pathogen: Erysiphe cruciferarum.
• Symptoms: White powdery growth on upper leaf surfaces, reduced vigor.
• Favored by dry, warm conditions.
• Management: Resistant varieties, fungicides, avoid excess nitrogen, reduce drought stress.

• Pathogen: Albugo candida (oomycete, not true fungus).
• Symptoms: White blisters on leaf undersides, yellow patches above, stem distortion, leaf galls.
• Favored by cool, moist weather.
• Management: Resistant varieties, crop rotation, fungicides.

• Pathogen: Mycosphaerella brassicicola.
• Symptoms: Grey leaf lesions with black dots in concentric rings, reduced growth, delayed harvest.
• Spread by seed and debris.
• Management: Hot water seed treatment, fungicides, remove infected plants and debris.

• Pathogens: Sclerotinia sclerotiorum, S. minor.
• Symptoms: Water-soaked lesions, fluffy white mycelium, black sclerotia inside stems.
• Favored by high humidity and dense canopy.
• Management: Improve air circulation, avoid injury, crop rotation, remove infected debris.

• Pathogen: Rhizoctonia solani.
• Symptoms: Tan or brown lesions on outer leaves, rapid head rot.
• Favored by wet, poorly drained soils.
• Management: Raised beds, proper fertilization, maintain plant health.

• Pathogen: Phytophthora megasperma.
• Symptoms: Leaf margin discoloration (red/purple), root and stem rot, plant wilting and death.
• Favored by poorly drained soils.
• Management: Improve drainage, crop rotation, soil treatments, fungicides.

• Use disease-free seed and resistant varieties.
• Practice crop rotation and field sanitation.
• Maintain proper drainage and avoid plant injury.
• Apply fungicides judiciously as needed.
• Monitor regularly for early detection and control.

• Apple is susceptible to various fungal, bacterial, and physiological diseases.
• Major diseases impact yield, fruit quality, and tree longevity.
• Effective management requires understanding pathogen biology and disease cycles.
• Integrated approaches combine cultural, chemical, and genetic methods.

• Caused by Venturia inaequalis (fungus).
• First reported in Sweden (1819); in India, Kashmir valley (1935).
• Most economically important apple disease worldwide.

• Black, circular, velvety spots on upper leaf surface; may coalesce.
• Leaves become twisted, yellow, and may drop prematurely.
• Fruits develop sooty, gray-black lesions, later sunken and tan.
• Infected fruits may crack and become deformed; young fruits may drop.

• Primary inoculum: ascospores from fallen leaves in spring.
• Ascospores dispersed by wind and rain during wet periods.
• Secondary spread: conidia dispersed by wind and rain.

• Sanitation: remove and destroy fallen leaves.
• Use resistant varieties: Emira, Redfree, Ambstraking, Ambroyal, Ambrich, Ambred.
• Fungicide sprays: captan (0.2%), dodine (0.25%) after petal fall.
• Apply difolatan (0.3%) at green bud stage, followed by captan at petal fall.

• Caused by Podosphaera leucotricha (fungus).
• White or grey powdery patches on young leaves, shoots, and fruits.
• Leaves become narrow, curled; twigs covered with powdery mass.
• Fruits remain small, deformed, with roughened surface.

• Overwinters as mycelium in buds; spreads by wind-borne conidia.
• Sanitation: remove infected shoots and plant debris.
• Pre-bloom spray: lime sulphur (1:60); fungicides: dinocap (0.05%).
• Resistant varieties: Maharaja Chunth, Golden Chinese, Yantarka Altaskya, Dolgoe.

• Caused by Erwinia amylovora (bacterium).
• Affects blossoms, shoots, branches, fruits, and rootstock.
• Blossoms become water-soaked, turn brown/black, shrivel.
• Shoots wilt, forming “shepherd’s crook”; leaves blacken along veins.
• Milky, sticky ooze may appear on infected tissues.

• Bacteria overwinter in cankers and woody tissue.
• Spread by insects (bees, flies, ants) and rain splash.
• Prune and destroy infected parts 30 cm below visible symptoms.
• Disinfect tools with 10% sodium hypochlorite after each cut.
• Dormant sprays: copper sulphate or Bordeaux mixture; streptomycin for blossom protection.

• Caused by Agrobacterium tumefaciens (bacterium).
• Galls form on roots and stems near soil line; initially white/flesh-colored, later hard and corky.
• Plants become stunted with chlorotic leaves.

• Use disease-free planting material; avoid wounding roots and stems.
• Crop rotation with cereals or maize.
• Biological control: Agrobacterium radiobacter strain K1026 applied to wounds.
• Penicillin or vancomycin offers partial control.

• Combine cultural, chemical, and genetic resistance strategies.
• Regular monitoring and early detection are essential.
• Sanitation and removal of infected material reduce inoculum.
• Use of resistant varieties minimizes chemical dependence.

• Apple is affected by several fungal and bacterial diseases.
• Major diseases include apple scab, powdery mildew, fire blight, and crown gall.
• Effective management requires understanding pathogen biology and integrated control methods.

• Apple scab: Venturia inaequalis
• Powdery mildew: Podosphaera leucotricha
• Fire blight: Erwinia amylovora
• Crown gall: Agrobacterium tumefaciens
• Other diseases: Black rot, sooty blotch, flyspeck, Phytophthora crown rot

• Caused by Venturia inaequalis (fungus).
• First reported in Sweden (1819); in India, on Ambri variety in Kashmir (1935).
• Favored by cool, moist conditions during spring.

• Black, circular, velvety spots on upper leaf surface; may coalesce.
• Leaves become twisted, yellow, and may drop prematurely.
• Fruits show sooty, gray-black lesions that become sunken and tan.
• Severely affected fruit may crack and drop early.

• Primary inoculum: ascospores from fallen leaves in spring.
• Secondary spread: conidia dispersed by wind and rain.
• Infection favored by wet weather during bud break and early fruit development.

• Sanitation: remove and destroy fallen leaves.
• Use resistant varieties: Emira, Redfree, Ambstraking, Ambroyal, Ambrich, Ambred.
• Fungicide sprays: captan (0.2%), dodine (0.25%) after petal fall.
• Apply difolatan (0.3%) at green bud stage, followed by captan at petal fall.

• Caused by Podosphaera leucotricha (fungus).
• White or gray powdery patches on young leaves, shoots, and fruits.
• Leaves become narrow, curled, and distorted; twigs covered with powdery mass.
• Affected fruits are small, deformed, and roughened.

• Overwinters as mycelium in buds and fruits.
• Spread by wind-borne conidia in spring and summer.
• Sanitation: remove infected shoots and plant debris.
• Spray lime sulphur (1:60) pre-bloom; dinocap (0.05%) or wettable sulphur.
• Resistant varieties: Maharaja Chunth, Golden Chinese, Yantarka Altaskya, Dolgoe.

• Caused by Erwinia amylovora (bacterium).
• Affects blossoms, shoots, branches, and sometimes rootstock.
• Blossoms become water-soaked, then brown to black and shriveled.
• Shoots wilt, forming “shepherd’s crook”; leaves blacken along veins.
• Infected fruit shrivel, turn black, and may remain attached.

• Bacteria overwinter in cankers and healthy woody tissue.
• Spread by insects (bees, flies, ants) and rain splash.
• Infection occurs during warm, humid weather, especially at bloom.

• Prune and burn infected twigs and branches 30 cm below visible symptoms.
• Disinfect tools with 10% sodium hypochlorite after each cut.
• Control insect vectors.
• Use resistant varieties where available.
• Dormant sprays: copper sulphate or Bordeaux mixture; streptomycin for blossom protection.

• Cedar apple rust: Gymnosporangium juniperi-virginianae – orange leaf spots, fruit lesions.
• Crown gall: Agrobacterium tumefaciens – tumor-like galls on roots and stems.
• Black rot: Botryosphaeria obtusa – fruit rot, leaf spots, cankers.
• Sooty blotch and flyspeck: superficial fruit blemishes, reduce market value.
• Phytophthora crown, collar, and root rot: Phytophthora spp. – root decay, tree decline.

• Combine cultural, chemical, and genetic approaches for effective control.
• Regular orchard sanitation and pruning are essential.
• Use disease-resistant varieties when possible.
• Apply fungicides and bactericides judiciously, following recommended schedules.
• Monitor orchards regularly for early detection and management.

• Pea (Pisum sativum) is susceptible to several fungal diseases.
• Major diseases include Fusarium wilt, powdery mildew, downy mildew, rust, and Ascochyta blight.
• Effective management requires understanding pathogen biology and disease epidemiology.

• Caused by Fusarium oxysporum f. sp. pisi.
• Initial symptoms: drooping, yellowing, and premature leaf drop.
• Pod formation is severely affected; collar region shows necrosis and discoloration.
• Dark brown vascular discoloration visible in stem cross-section.

• Pathogen survives in soil for long periods; infects via root hairs.
• Primary infection: soil, seed, water; secondary: conidia via rain splash.
• Favored by soil temperatures of 23–27°C and warm weather.
• Seed treatment with carbendazim (2 g/kg) and soil drenching with copper oxychloride (0.25%) recommended.

• Caused by Erysiphe pisi.
• Appears as white powdery spots on leaves, stems, and pods.
• Severely infected leaves become chlorotic, distorted, and may fall.
• Pods may be small and malformed.

• Spread by airborne spores; thrives in warm (15–25°C), humid (>70%) conditions.
• Cultural control: use resistant varieties, destroy infected stubble, avoid adjacent sowing to previous pea fields.
• Chemical control: sprays of benomyl, carbendazim, sulphur, or triadimefon as per recommended doses and intervals.

• Caused by Peronospora viciae.
• Grayish-white mold on lower leaf surface; yellowish area on upper side.
• Infected leaves turn yellow, die; stems may be stunted and distorted.
• Brown blotches and mold may develop on pods.

• Primary infection: soil, seed, water; secondary: sporangia via rain splash or wind.
• Favored by high humidity and low temperatures (5–15°C).
• Remove and burn diseased plants promptly to reduce inoculum.

• Caused by Uromyces pisi.
• Initial symptoms: leaf flecking, progressing to reddish-brown pustules.
• Pustules merge, burst, and release brown spores; severe cases cause plant drying and yield loss.

• Survives on infected plant debris and alternate hosts (e.g., Euphorbia).
• Favored by frequent precipitation, dew, and temperatures of 20–25°C.
• Cultural control: destroy debris, crop rotation with non-legumes, mixed cropping.
• Chemical control: sulphur or triadimefon sprays as per recommendations.

• Caused by Ascochyta pisi, A. pinodes, and A. pinodella.
• Symptoms: purplish-brown flecks on lower leaves, stems, tendrils; lesions enlarge and coalesce.
• Severe infection causes foot rot (purplish-black lesions at soil line), lodging, and pod lesions.
• Pod infection leads to small, discolored, or shrunken seeds.

• Ascospores spread by wind; conidia by rain splash.
• Primary infection from diseased seed or soil debris.
• Favored by warm, humid conditions (15–25°C).
• Use resistant varieties (e.g., B-90, CDC Frontier, CDC Luna), seed treatment with thiabendazole, and crop rotation.

• Combine cultural, chemical, and genetic resistance strategies for effective control.
• Use certified disease-free seed and resistant varieties.
• Practice crop rotation and field sanitation.
• Apply fungicides judiciously based on disease monitoring and recommendations.

• Cucurbits include cucumber, melon, watermelon, pumpkin, squash, and gourds.
• Major diseases: Downy mildew, Powdery mildew, Fusarium wilt, Angular leaf spot, Cucumber mosaic, and Tospovirus.
• Diseases caused by fungi, bacteria, and viruses.
• Effective management requires accurate diagnosis and integrated control strategies.

• Pathogen: Pseudoperonospora cubensis (oomycete fungus).
• Hosts: All major cucurbits.
• Symptoms: Small yellow, water-soaked lesions on upper leaf surface; lesions turn brown and necrotic.
• Severe infection causes leaf curling, death, and reduced fruit quality.

• Survives on collateral hosts and plant debris.
• Spread by wind-borne sporangia and rain splash.
• Management: Remove weeds, avoid overhead irrigation, use resistant varieties.
• Fungicide sprays: Metalaxyl, chlorothalonil, or zineb at recommended intervals.

• Pathogens: Erysiphe cichoracearum and Sphaerotheca fuliginea.
• Symptoms: White, powdery mycelium on both leaf surfaces, stems, and petioles.
• Leads to leaf yellowing, drying, premature defoliation, and fruit deformation.

• Overwinters as cleistothecia or on collateral hosts.
• Spread by wind-borne conidia.
• Management: Use resistant varieties, ensure good air circulation, apply fungicides (e.g., Calixin, Karathane).

• Pathogen: Fusarium oxysporum f.sp. niveum.
• Symptoms: Seedling damping-off, yellowing and wilting of leaves, vascular discoloration, stem lesions.
• Older plants may collapse suddenly, especially under stress.

• Survives in soil as chlamydospores for years.
• Primary infection from soil; secondary spread by water and wind.
• Management: Seed treatment (Carboxin/Carbendazim), crop rotation, use resistant varieties, balanced fertilization, maintain soil pH 6.5–7.0.

• Pathogen: Pseudomonas syringae pv. lachrymans (bacterium).
• Symptoms: Small, angular, water-soaked leaf spots; milky exudate under moist conditions.
• Lesions dry to form shot-holes; fruit spots cause internal decay and deformation.

• Seed-borne and survives in crop debris.
• Spread by irrigation water and handling wet plants.
• Management: Use pathogen-free seed, crop rotation, avoid overhead irrigation, apply bactericides (e.g., Streptomycin), destroy crop debris.

• Pathogen: Cucumber mosaic virus (CMV).
• Symptoms: Mosaic, leaf distortion, stunting, flower abnormalities, fruit deformation.
• Transmitted by aphids (non-persistent) and cucumber beetles; survives on weeds and alternate hosts.

• Rogue infected plants and eliminate weed hosts.
• Control aphid vectors with insecticides (e.g., monocrotophos, phosphamidon).
• Use resistant varieties where available.

• Pathogen: Tomato spotted wilt virus (TSWV), a tospovirus.
• Symptoms: Leaf bronzing, chlorotic spots, mosaic, die-back, stunting, fruit ring spots and necrosis.
• Transmitted by thrips (e.g., Frankliniella occidentalis, Thrips palmi).

• Use mesh screening and phytosanitary measures in nurseries.
• Avoid planting near thrips reservoirs (ornamentals, older crops).
• Control weeds and volunteer cucurbits.
• Implement early insecticide programs to manage thrips populations.

• Combine cultural, chemical, and biological methods for effective disease control.
• Use resistant varieties and certified seeds.
• Practice crop rotation and field sanitation.
• Monitor regularly for early detection and timely intervention.