This presentation is related to diseases caused in Isabgol and its symptoms, etiology, epidemiology and management with full description.

1. AN ASSIGNMENT ON
DISEASES OF ISABGOL (Plantago ovata)
PL.PATH- 506
SUBMITTED TO: SUBMITTED BY:
Prof.(Dr) SHYAMA SUNDAR MOHAPATRA USHA RANI SAHOO(209)
Dr.(Mrs) GAYATRI BISWAL M.Sc. (Ag.), 1st Year
Dept. OF PLANT PATHOLOGY

2. 1. DOWNY MILDEW
CAUSAL ORGANISM - Peronospora plantaginis.
SYMPTOMS –
 In general, the disease appears during spike initiation.
 Small and pale yellow patches appear on the leaves of the
affected plants.
 On the upper surfaces of leaves, chlorotic areas are seen,
however, just below the chlorotic areas, ash white frost like
mycelial growth are seen on the lower surfaces of such leaves.
 Some times, chlorotic streaks running along the midrib of the
leaves are seen. In severe cases, entire plant looks blighted.

3. ETIOLOGY:
 Hyphae of Peronospora plantaginis are intercellular.
 Sporangiophores are slender, tree like with characteristic erect
trunk. They are dichotomously branched and grey to pale
yellow in colour.
 Sporangia formed on the sporangiophores are sub hyaline in
colour and are broadly elliptical to sub globose in shape.
DISEASE CYCLE :
 The disease is both seed and soil borne in nature.
MANAGEMENT :
 Seed treatment with Metalaxyl @5g/Kg of seed .
 Fungicidal sprays with Bordeaux mixture or Copper
Oxychloride is found to be useful.

4. INFECTED FLORETS Perenospora plantaginis
DOWNY MILDEW OF ISABGOL

5. 2. DAMPING OFF OF SEEDLINGS
CAUSAL ORGANISM:
 Damping off of this crop has been reported to be caused by
Pythium ultimum and Rhizoctonia solani.
SYMPTOMS:
 In pre-emergence damping off, young seedlings may wither
and fall down on the soil surface.
 In post emergence, darkened, water soaked spots may
develop on collar region of the seedlings. Such lesions
usually enlarge leading to the death of the seedlings.
 Disease may be severe at high temperature and humidity
prevalent at the time of sowing.

6. DISEASE CYCLE:
 The disease is soil borne in nature.
MANAGEMENT:
 Seed treatment with any suitable fungicide like Metalaxyl @
5 g/ kg of seed should be done.
Rhizoctonia solani

7. 3. WILT DISEASE
CAUSAL ORGANISIM :- Fusarium solani & Fusarium
oxysporum
SYMPTOMS:
 Discoloration of roots.
 Accumulation of large amount of hyphae within xylem
vessels.
 Green leaves turn silver and wilting of plant occur and
cortical root rot are observed.
DISEASE CYCLE:
 Primary inoculum- Mycelium present in soil and infected
stubbles.

8. WILT DISEASE IN
ISABGOL

9. ETIOLOGY :
 Micro conidia- hyaline, single celled and oval.
 Macro conidia- sickle shaped,2-5 celled, septate.
 Chlamydospores are produced as resting spores.

10. MANAGEMENT:
 Field sanitation.
 Deep summer ploughing.
 Removal of infected plant.
 Crop rotation with non hosts crop.
 Seed treatment with Benlate or Bavistin @2.5g/kg of seed or
use 4 g T.viride or 2 g carbendazim/kg seed.
 Drenching with 1% Bordeaux mixture or blue copper @
0.25%.

11. 4. POWDERY MILDEW
CAUSING ORGANISM:- Erysiphe polygoni
SYMPTOMS:
 Appears at the time of flowering.
 Appearance of powdery mass of spores on the leaves which
produces small white or grayish color spots.
 These spots enlarges gradually & eventually cover entire
plant surface.
DISEASE CYCLE:
 Overwinter – Cleistothecia.
 Initial infection- wind borne conidia OR ascospores.

12. POWDERY MILDEW IN
ISABGOL

13. ETIOLOGY:
 Eryshiphe produces oidium.
 Mycelium is ectophytic & hyaline.
 Conidiophore is short, small and hyaline.
 Conidia is barrel shaped with flat ends & is produced in
chains.
 Cleisthothecium ( Contain ornamental appendages & is dark
brown in colour & globose) is produced which have asci that
carry ascospore.

14. CLEISTOTHESIA
CONIDIA AND
CONIDIOPHORE

15. EPIDEMOLOGY:
 Temp - 20˚-21˚C.
 Prolonged cloudy weather.
MANAGEMENT:
 Field sanitation.
 Crop rotation.
 Field spray of wettable sulfur or karathane -0.2%, after the
appearance of the disease ,2-3 spray at 15 days interval.

16. 5. ALTERNERIA LEAF BLIGHT
CAUSING ORGANISIM: Alterneria alternata
SYMPTOMS:
 Older and matured leaves are more affected.
 Dull yellowish colors lesions are observed on the leaf tips.
 Irregular necrotic spots are formed on the leaves .
 Spots enlarges resulting in blackening & drying of affected
plants.
 Shriveling and blackening of seeds of infected plant are also
observed.

17. Alternaria leaf spot

18. ETIOLOGY:
 Mycelium- hyaline, olive,branched septate
 Conidiophore- Septate, unbranched, geniculate or straight
 Conidia- Single or chained, smooth, bottle shaped contain a
beak and muriform septate.
EPIDEMIOLOGY:
 Temp – 25˚C & High humidity.

19. Alterneria alternata under microscope.

20. DISEASE CYCLE:
 Primary inoculum- External seed borne and soil borne.
 Secondary inoculum- Air borne conidia
MANAGEMENT:
 Field sanitation.
 Deep summer ploughing.
 Removal of infected plant.
 Crop rotation with non hosts crop.
 Seed treatment with Benlate or Bavistin @2.5g/kg of seed or
use 4 g T.viride or 2 g carbendazim/kg seed.