This document discusses non-infectious and latrogenic plant diseases. It defines non-infectious diseases as those not caused by parasites and which cannot be transmitted between plants. Examples mentioned include freezing or heat injury to various crops, as well as physiological disorders from imbalanced water or mineral levels. Latrogenic diseases are those caused or increased by plant protection chemicals, such as fungicides increasing other fungal diseases. Specific non-parasitic diseases highlighted include blossom end rot of tomatoes, cracking of carrots, and malformation of mangoes due to ethylene stress.
1. NON-INFECTIOUS AND LATROGENIC DISEASES
COLLEGE OF AGRICULTURAL TECHNOLOGY
(Affiliated to Tamil Nadu Agricultural University, Coimbatore-3)
Kullapuram (Po),ViaVaigai Dam, Theni-625 562
STUDENTS
Miss. DEEPA.P
Mr.GOWTHAM.M
COURSE TEACHER
Dr. PARTHASARATHY S
Asst. Professor (Plant Pathology)
2. NON-INFECTIOUS DISEASES
• These are diseases in which no animate agent/parasite is
associated
• Therefore they be cannot be transmitted from one
diseased plant to another healthy plant
• Since no parasite is associated with these diseases they are
also known as non-parasitic diseases or physiological
disorder
3. FREEZING INJURY - Tissue decay in potato and sweet
potato
HIGH TEMPERATURE - Heat cancer of flax, tip burn in
betel vine/pototo, hard lumps in papaya fruits
LOW TEMPERATURE - induced STRESS ETHYLENE
is responsible for malformation in mango
6. • IMBALANCED WATER SUPPLY TO THE PLANTS - Bitter pit
in apple, blossom end rot of tomato, straight head in rice
• MOISTURE IMBALANCE AND EXTREME VARIATION IN
DAY AND NIGHT TEMPERATURE - Fruit crack in fully grown
pomegranate fruits
• EXCESSIVE WATER SUPPLY - Cracking of carrot, beets,turnips,
potatoes, hollow heart of potato, granulation in citrus
• REDUCED SUPPLY OF OXYGEN TO THE ROOTS - Tip
burning in paddy
• INJURIOUS ATMOSPHERE - Apple scald, black tip of mango
13. LIGHTNING INJURY - Damages to potato plant due to
lightening.
MINERAL EXCESS - Cat facing in tomato(excess N in the
soil), crinckle leaf of cotton(Mn toxicity).
MINERAL DEFICIENCY - Pahala blight of sugar cane(Mn
deficiency), Khaira diseases of Rice(Zn deficiency), blossom
end rot of tomato and other fruits(Ca deficiency), Whiptail of
cauliflower(Mo deficiency), Hens and chicken in grapes(Zn and
B micronutrient deficiency).
18. LATROGENIC DISEASES
The effect of plant protection chemicals which result
in either the appearance of new diseases or increase
the diseases already present.
Eg; Zineb controlling Downy mildew in Grapes but
increases the incidence of powdery mildew.
