Agri Books

Pear is an important fruit crop grown mainly in the temperate climate of the world. Among temperate fruits, the pear is a highly cultivated fruit crop in India followed by Apple.

In this post, we mentioned some of the most important diseases of pear that affect fruit yield, as well as their causing organism, symptoms, and their management.

1. Pear Scab

Causal organism: Fungus; Venturia pirina.

Symptoms

• Twisted or puckered leaves develop black, round patches on their upper surface.
• The sores eventually turn sunken and brown, with spores along their edges.
• Infected fruit becomes deformed and may crack, allowing secondary organisms to enter.

Management:

• Silvertip to green stage mancozeb spray @ 2g/l or chlorothalonil @ 2g/l

2. Powdery Mildew

Causal organism: Fungus; Podosphaera leucotricha.

Symptoms

• On the leaves, white powdery growth with oidia occurs on the top and lower sides.
• White powdery growth on the stem.
• On the fruits, there is a whitish powdery growth, but it is dry.

Management:

• Calcium Oxychloride (0.3%) spray on plant.
• For Biological control use Erwinia herbicola and Psuedomonas fluorescens as antagonistic sprays.

3. Fire Blight

Causal organism: Bacteria; Erwinia amylovora.

Symptoms

• The fire appears to have burnt infected areas. Infected plant parts may emit a watery slime.
• The disease has the potential to wipe off entire trees.
• Fruits infected early remain tiny, and appear shrivelled, black and ‘water soaked’.
• They are still linked to the cluster.
• Late-infected fruits are less delicious.

Management:

• Spray of Copper Oxychloride (0.3%) and Streptocycline (0.05%).

4. Leaf Spot

Causal organism: Fungus; Fabraea maculata.

Symptoms

• Spot can be found on petioles, leaves, shoots and fruits.
• Spots form and highly affected leaves fall to the ground too soon.
• Cause the fruit to crack and drop.
• Some lesions develop into superficial cankers, but most are walled off during the next growing season, as the cankers rarely persist in two-year-old wood.

Management:

• Spray of Copper Oxychloride (0.3%) and Streptocycline (0.05%).

5. Pear Decline

Causal organism: Phytoplasma like organism; PLO’s.

Vector: Pear Psylla

Symptoms

• Pear decline is divided into two stages: quick decline and slow decline.
• Trees may wilt, burn, and die in a few weeks or lose vigour over multiple seasons, with scant foliage, little or no terminal development, and reduced leaf size.
• On infected trees, an abnormal early red leaf colouration has been observed.

6. Crown Gall of Pear

Causal organism: Bacteria; Agrobacterium tumefaciens.

Symptoms

• Small overgrowths or galls on the roots, crown, trunk, or canes are the first signs of the disease.
• Galls typically form on the plant’s crown or trunk at the soil level, or on underground roots.

Related Posts

Diseases of Mango

Banana: Diseases and Their Management

Grape: Diseases, Symptoms and Their Management

Citrus: Diseases, Symptoms and Their Management

Sources

ICAR