Question

Discuss cultivation of apple under the following heads: Soil and climate, major varieties, propagation and rootstock and major diseases and their management.

Hint:

Remember: Apple cultivation requires temperate climate with adequate winter chilling, well-drained loamy soils (pH 5.5-6.5), and careful selection of varieties and rootstocks. Major diseases like apple scab and powdery mildew require integrated management through resistant varieties, cultural practices, and timely fungicide applications.

Answer 1

Step 1: Soil and climate requirements for apple cultivation.
Climate requirements:

• Temperature:
  • Apples require temperate climate with distinct winter and summer seasons
  • Optimum temperature range: 21-24°C during growing season
  • Winter chilling requirement: 1000-1600 hours below 7°C for proper bud break and flowering
  • Can tolerate temperatures as low as -30°C in dormant stage
  • Summer temperatures above 35°C can affect fruit quality
• Rainfall:
  • Annual rainfall requirement: 1000-1250 mm
  • Rainfall should be well-distributed throughout the year
  • Excessive rainfall during flowering affects pollination
  • Hailstorms can damage fruits and trees
• Altitude:
  • Grown at altitudes of 1500-2700 meters above sea level
  • In India, major apple-growing regions are in Himalayan states (Jammu & Kashmir, Himachal Pradesh, Uttarakhand)
• Sunlight:
  • Require full sunlight for at least 6-8 hours daily
  • Adequate sunlight ensures proper fruit color development

Soil requirements:

• Soil type: Well-drained deep loamy soils with good organic matter
• Soil depth: At least 1-1.5 meters depth for proper root development
• Soil pH: Slightly acidic to neutral (pH 5.5-6.5)
• Soil drainage: Excellent drainage essential - waterlogging causes root rot
• Soil fertility: Rich in organic matter with good nutrient-holding capacity
• Avoid heavy clay soils, shallow soils, and saline/alkaline soils

Step 2: Major varieties of apple.
Popular varieties grown in India:

• Royal Delicious: Most popular commercial variety, red color, excellent quality
• Red Delicious: Sweet flavor, conical shape, deep red color
• Golden Delicious: Yellow-green color, sweet, excellent for eating fresh
• Rich-a-Red: Early maturing, deep red color, good shelf life
• Vance Delicious: High yielding, attractive red color
• Starking Delicious: Striped red color, good quality
• Ambri: Traditional Kashmiri variety, long storage life
• Chaubattia Princess: Developed in India, good for mid-hills
• Chaubattia Anupam: Early maturing, disease resistant
• Oregon Spur: Spur-type variety, compact growth, high yield

Other international varieties:

• Fuji, Gala, Granny Smith, Pink Lady, Braeburn, Honeycrisp

Step 3: Propagation and rootstock.
Propagation methods:

• Budding: Most common method for commercial propagation
  • T-budding or shield budding done in spring (March-April)
  • Chip budding also successful
  • Budwood collected from disease-free mother plants
• Grafting:
  • Tongue grafting or whip grafting in winter
  • Used for top-working or changing varieties
• Layering: Not common for commercial propagation
• Tissue culture: Modern method for disease-free plants

Rootstocks used in apple cultivation:

• Vigorous rootstocks:
  • Seedling rootstock: Grown from seeds of crab apple or commercial varieties
  • Malling-Merton (MM) series: MM.111, MM.106 - semi-vigorous, widely used
• Semi-dwarfing rootstocks:
  • M.7: Adaptable to various soils, resistant to collar rot
  • MM.106: Most popular in India, semi-vigorous, early bearing
  • M.26: Semi-dwarf, precocious, requires support
• Dwarfing rootstocks:
  • M.9: Most popular dwarfing rootstock worldwide, early bearing, requires support
  • M.27: Very dwarfing, for high-density planting
• Characteristics of good rootstock:
  • Good anchorage and adaptability to soil conditions
  • Resistance to diseases (woolly aphid, collar rot)
  • Compatibility with scion varieties
  • Influence on tree size, precocity, and yield

Step 4: Major diseases of apple and their management.

• Apple Scab (Venturia inaequalis):
  • Symptoms: Olive-green to black velvety spots on leaves and fruits; fruit cracking
  • Management:
    • Grow resistant varieties
    • Remove and destroy fallen leaves
    • Spray fungicides like Captan, Mancozeb, or Carbendazim at green tip, pink bud, and petal fall stages
• Powdery Mildew (Podosphaera leucotricha):
  • Symptoms: White powdery coating on leaves, shoots, and flowers; stunted growth
  • Management:
    • Prune and destroy infected shoots
    • Avoid excess nitrogen fertilization
    • Spray Sulfur, Karathane, or Triadimefon at 10-15 day intervals
• Fire Blight (Erwinia amylovora):
  • Symptoms: Bacterial disease; blossoms and shoots look burnt, cankers on branches
  • Management:
    • Remove and destroy infected parts
    • Disinfect pruning tools
    • Spray Streptomycin or Bordeaux mixture during bloom
• Collar Rot (Phytophthora cactorum):
  • Symptoms: Rot at the base of trunk (collar region), leaf yellowing, tree decline
  • Management:
    • Use resistant rootstocks (MM.111, MM.106)
    • Ensure proper drainage
    • Avoid planting too deep
    • Drench with Metalaxyl or Fosetyl-Al
• Alternaria Leaf Spot:
  • Symptoms: Small brown spots with concentric rings on leaves
  • Management:
    • Collect and destroy fallen leaves
    • Spray Mancozeb or Iprodione

Integrated disease management approach:

• Use certified disease-free planting material
• Select resistant varieties and rootstocks
• Follow proper orchard sanitation
• Ensure proper pruning for air circulation
• Balanced nutrition to avoid susceptibility
• Need-based fungicide application following warning systems