Environmental condition (Temp. and R.H.) in storage and transit have also found to play important role in the development of post harvest diseases of the fruit crops; optimum temp. and relative humidity should maintained.

1. Dr. Khushboo Dubey
BIOLOGICAL CONTROL OF POST-HARVEST DISEASES OF FRUITS

2. Introduction :
 A post harvest loss, is any change in quality or
quantity of a product after harvest that prevents
or alters its intended use or decrease its
value.world wide post harvest losses have been
estimated to be 50% of the harvested crops and
much of this is due to rots caused by
microorganism.
 Biological control :
Biological as the practice in which or process
where by the undesirable effects of an organism
are reduced through the agency of another
organism that is not the host plant, the pest or
pathogen or man.(Garett 1965)
 Antagonist :
The organism which suppress the growth of
another organism is known as antagonist.

3. Sr.No. Fruits Losses (%)
1 Mango 40
2 Banana 20-80
3 Citrus 20-85
4 Grapes 27-30
5 Papaya 40-100

4. METHODS OF BIOLOGICAL CONTROL
1) Natural plant products. E.g. essential oil
from leaves of melanleuca leucadendron ,
ocium canum and citrus medica able to
protect several stored commodities from
biodegradation by Aspergillus flavus and
A. versicolor.
2) Using genetic engineering.(Fokkema and
van den heuvel 1986) E.g. development of
deletion mutant of pseudomonas syringae,
ice nucleation activity, this technology to
biological control freeze damage.

5. 3) Antagonistic microorganisms as biocontrol
agents
i) Naturally occuring antagonists
ii)Artificially introduced antagonists
4) Antagonists in controlled storage :
Fruits are subjected to wide range of
storage condition to delay their microbial
physiological deterioration. E.g. Rizopus
stolonifer is more sensitive to low
temperatures than many microorganisms .

6. MODE OFACTION OFANTAGONISTS
Contd…
Antagonism, in general operates in three ways viz.,
•Antibiosis: release of metabolites or chemicals
by the antagonist which may suppress or kill the
pathogen.
•Competition : where antagonist may deprive the
pathogen of the food material and latter may starve.
•Predation or Parasitism : in which the antagonist
may parasitize the pathogen and kill it.

7. Biological Control of Post Harvest Diseases of Important Fruit
Crops
Hosts Diseases Biological control Reference
Mango Stem end rot Bacillus licheniformis
(107-108 cfu/ml)
Korsten et al., (1992)
Anthracnose Bellary jail Nargund, M.K.,
Basavarajappa. (2006)
Fruit rot Trichoderma spp.
(5x105 spores/ml)
Patil. (1992)
Grapes Gray mould Debaryomyces hansenii Chalutz and Wilson. (1990)
Banana Crown rot Bacillus subtilis
(107-108 cfu/ml)
Kulkarni, S. & Hedge, Y. R.
(2006)
Contd…..

8. Citrus Stem end rot Bacillus subtilis
(107-108 cfu/ml)
Pusey and Wilson
(1988)
Black rot Yeasts
(106-107 cfu/ml)
Chalutz and Wilson
(1990)
Penicillium rot Trichoderma viride
(5x105 spores/ml)
de Maltos (1983)
Green mould Bacillus pumilus
1.6 x 1010-12 cfu/ml
Guava Fruit rot / Canker Trichoderma spp.
(5x105 spores/ml)
Mujumdar et al., (1995)
Contd…

9. Jack fruit Rot Trichoderma lignorum
(5x105 spores/ml)
Dutta (1983)
Coconut Rot Aspergillus niger Dutta and Chatterjee
(1998)
Strawberry Rot Trichoderma spp.
(5x105 spores/ml)
Tronsmo and Dennis
(1983)
Apple Rot Antagonistic mixture Janisiewez (1988)
Penicillium rot Candida spp. Mc Laughlin et al
(1992)

10. Merits of Biocontrol agents :
 Biocontrol agents are harmless to human beings and
animals.
 Cheaper than pesticides by 50%.
 Highly effective throughout the crop growth period with
high rhizosphere competence.
 Easy to deliver.
 Broad spectrum activity, productivity and production.
 Improve plant growth.
 Induce systemic resistance.
 High cost : benefits ratio and environmentally safe.
 There is no risk of resistance development in pathogen
and residual effects in food and ground water.
 They are also compatible with biofertilizers.
 Amenability for mass production.

11. SYMPTOMATOLOGY
Mango :-
Causal organism : Colletotrichum acutatum.
Symptoms :
Circular, dark brown specks which enlarge and coalesce to form
large spot and the lesions extend to the pulp; salmon or dark coloured dot like
acervuli appear at later stage

12. Citrus Penicilium rot :
Organism : Penicillium digitatum.
Symptoms :
Affected areas gets covered with green or blue
mouldy growth and the fruits emits a foul smell.

13. Guava :
Fruit rot / Canker :
Causal organism : Pestalotia psidii.
Symptoms :
Rust coloured necrotic spots which later increases
and extends to the pulp. The centre of infection
gets depressed.

14. Banana :
Crown rot of banana
Causal organism : Colletotrichum musae.
Symptoms :
Crown rot, light brown rot turns dark brown and
extends to the fingers, fruit spot, fruit rot, circular light
brown spots enlarge and coalesce to form larger dark
brown spots. The lesions invade the pulp at later stage

15. Grapes
Gray mould :
Causal organism : Botrytis cinerea.
Symptoms :
Small, circular faint coloured spots. The
affected areas turns slightly brown. The skin
slips from the diseased spot, affected fruits
shrivel and turn dark brown.

16. Jackfruit:
Jackfruit rot :
Causal organism : Rhizopus artocarpi.
Symptoms :
Premature fall of young fruits due to rotting and
may result in heavy loss in yeild under unusual
humid conditions.

17. conclusion
 Bacterial antagonist viz. Bacillus subtilis, B.
licheniformis, B. pumilus; Fungal antagonist viz.,
Trichoderma viride, T. lingorum; Aspergillus niger
and Yeasts (Candida spp.) were reported as
effective biocontrol agents for the management of
post harvest diseases of many fruit crops.
 Environmental condition (Temp. and R.H.) in
storage and transit have also found to play
important role in the development of post harvest
diseases of the fruit crops; optimum temp. and
relative humidity should maintained.