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Effect of nutrients on biomass production of Alternaria solani a leaf spot

pathogen of neem (Azadirachta indica L)

Abhijeet B. Pawar

K. K. Wagh Arts, Science & Commerce College Pimpalgaon (B),
Tal- Niphad, Dist- Nashik

* E-mail of corresponding author: abhipawar77@rediffmail.com

ABSTRACT

Alternaria solani was a potential pathogen of Azadirachta indica L, was isolated from
diseased Azadirachta indica L leaves from Nashik district and used for the present study.

Pathogen was grown on the Czapek-Dox liquid medium substituting or adding different
carbon, nitrogen to study biomass production. The growth as dry mycelial biomass was

th
observed on the 8 day of incubation period. A grate extent of growth variation was observed
on different carbon, nitrogen. Among the carbon source, lactose shows maximum biomass
while glucose with minimum biomass. From nitrogen source nickel nitrate shows maximum

and potassium nitrate with minimum biomass was recorded.
Key Words: Alternaria solani, Biomass, Pathogen.

INTRODUCTION
Azadirachta indica L is a native tree of India, a tropical tree especially suited to semi-

arid conditions. It is commonly known as Neem. It belongs to the family Meliaceae and is

becoming increasingly popular for its insect repellant traits and unique property of inhibiting
the nitrification process in the soil. The most active, currently identified ingredient of

Azadirachta indica L is 'azadirachtin'. The termite resistant Azadirachta indica L timber is
used as a building material and in making furniture and farm implements. This plant affected

by many fungi as leaf spot. Symptoms progress from lower to upper leaves. Leaf spots begin

as small brown areas. These areas enlarge and are surrounded by a border of yellow host
tissue. As the spots mature, concentric rings of raised and depressed brown tissue are evident.

Heavily infected plants often become defoliated.
The disease is caused by Alternaria solani Sorauer. The pathogen has worldwide

distribution and infects many types of solanaceous plants, both cultivated and weeds. Disease
o
development is favored by mild (24 - 29 C), rainy weather although it can develop at higher
temperature. Conidia develop lesions on the host. Profuse sporulation occurs when heavy

dews or rain are present. These conidia serve as secondary inoculums and are disseminated

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