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S. SUNDARARAMAN E 911 
i: Infection—infection from plant to plant favoured by conditions of moisture 
a Se and atmosphere, that is, rainy weather followed by wind and moist mugg 
- weather. The disease appears in. August and seems epidemic in years of 
~ heavy rainfall. Continued rain with spells of dry weather is congenial for its 
_ development. The rains wash down the fungus spores to lower portions of 
the plant, and the wind carries the spores from leaf to leaf and from plant to 
_ plant. The cultivator produces conditions favourable to the disease by his 
_ thick planting which tends to make plants touch each other, not admitting 
light and air which are essentiat-for healthy vigorous growth. 
7 
Effects of the disease. 
= The disease “VIEXPLANATION OF PLATE 4#° part where the plants 
__ manufactifre food. The disease makes its appearance in the growing period of 
- the crop and at a time when the rhizomes begin to develop. As. the fungus 
_ attacks directly the place where plant food is manufactured, the plants get 
= stunted Beat with Hiinlite “black! déts!° (Natural. sizey. healthy conditions the 
ss Op Bf alMinite Mask dots Magnified andes low ‘power! Showing spore pustules. 
the crop hagnéfteatado ofe Vermicularia X82 p.0b2e plants begin to die. 
fe 3. A single pustule as seen op high power of the microscope, showing _ 
= dark brown septate se of faleate spores, x 360 p. 
—— 4. Spores falcate-sin pos ot rate Wane Of ime granular contents. 
~~‘ The spapgdochia appear in ons yellow spots varyingin size. They are 
os 
ss aaggrevatSporex'sHowing several clutages. of 'gefmination’ forming! ‘thick-walled ip 
: 4 colour, 50-|dark ibrowanchlantydospores,  ; 860g. Numerous, erect, dark brown, 
_*~ septate, 85-168 » long (Plate II, figs. 2 & 3) ; spores, subfusoid, curved with a 
_ blunt point, hyaline, minutely guttulate, 17°5-24 » x 3°15-4:2 » (Plate I, 
fig. 4). On leaves, petioles and scale-like leaves on the gee ees of ginger in 
Amalapur Taluk, Godavari District. 
The hyphe are hyaline and septate. They vary in diameter from 2 to 8y. 
~ In old culture the hyphw become hight brown. ‘The spore clusters are formed 
abou submerged under the epidermis but on breaking the epidermis come 
_ out to the surface, and take on the character of Colletotrichum, the sete appear- 
ing to spring from the layer of sporophore (Plate II, fig. 3). The spores 
germinate in 4-6 hours, putting forth a germ-tube, and produce chlamydospores 
‘in 18 hours. These are formed at the end of germ-tubes (Plate I], fig. 5, a, 
= b, c,d). Some spores form chlamydospores without the intervention of the 
_— germ-tube. The chlamydospores are sometimes divided into cells each having 
a germ-pore. These are either round or ovate or irregularly lobed and are 
= generally dark-olive. When the spores begin to germinate they produce a 
‘ 
= ! 
rags? 
