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Cosnios wilt and that from the cashew nut, it was thought 
advisable to carry out a cross-inoculation experiment in order to 
test the pathogenicity of the cashew nut Fusarium with regard 
to one at least of the plants involved in the previous investigation 
into the wilt of carnation, Delphinium, Nigella and Cosmos. A 
large pot of healthy larkspur (Delphinium) seedlings happened 
to be available and it was therefore employed. The seedlings 
growing along two diameters of the pot taken at right angles to 
each other were so removed as to leave the remainder in four 
broken up. After inoculation the soil of the whole pot was 
gently kneaded into its former state. The viability of the conidia 
had been previously tested in hanging-drops. The results of 
this experiment were striking. Plants in both inoculated areas 
‘began to wilt on the sixth day and the great majority of them 
were dead in twenty-three days. Meanwhile, after twenty 
days, plants in both the control areas of the pot began to 
show signs of disease, and a further period of ten days proved 
fatal to practically all of them. Typical samples of dead or 
dying seedlings were taken at intervals from inoculated and 
control groups and were placed in a moist atmosphere after 
careful sterilisation. From all without exception, the Fusarium 
was recovered with mycelium and conidia resembling in all 
respects those obtained from the cashew nut Fusarium cultures. 
The wilted seedlings showed under the surface of the soil the 
blackened, soft and sunken area of stem typical of the previous 
wilt disease. This experiment provided further evidence, if 
such was required, of the virulent root-parasitism of the Fusarvum 
and it might have been taken to show the rapidity with which the 
fungus could spread across a bridge of soil. But, in this connec- 
tion, it should be remembered that the plants were fairly crowded 
in the pot and that there was opportunity for the fungus to 
spread from root to root. That it did so was shown by the 
general decay of the smaller roots of both inoculated and 
control plants. 
At the same time, young mango plants, chosen because 0 
their affinity to the cashew nut, were experimented with. the 
plants were healthy seedlings of eight to ten inches high and were 
in pots. Conidia from prune agar cultures were used. Masses 
of them were transferred to sterile distilled water in a watch-glass 
