88 QUEENSLAND AGRICULTURAL JOURNAL. {1 Jury, 1901, 
in the West Indian Islands with the presence of the spume fungus, and is describyd 
by them as being caused by Trichospheria sacchari, Mass., of which it is the 
Melanconium form. 
That the fungus of “Rod Snot’’ and Root Disease is only a formation of the 
| 
so-called ‘“ Rind Fungus,” rests on the sole authority of the able director of the Royyl 
me 
Botanic Gardens, Kew (sir W. Thiselton-Dyer). He states—*“ A healthy seedling 
sugar-cane was inoculated with the spores of Co//elotrichum faleatum, and at the end of 
twenty days developed the Melanconium stage of Trichospharia.” (Annals of Botany, 
xiy., p. 616, December, 1900.) This positive result, he al moreover, “is still open 
to independent confirmation.” G. Massee, who ‘suggested the possibility of such 
relationship in May, 1894, stated at the time that ‘ The necessary cultures for the 
verification or otherwise of this point are now being proceeded with.” (Avw Bulletin 
80, June, 1899. p. 177.) But it is not, however, on record that such verification wus 
ever secured. ‘lhe authorities in British India in declaring this association had, hovw- 
ever, as had been admitted, relied on the statement contained in the “ Report of 
the Barbados Commission’ of 1895—It lias been finally decided at Kew that 
Colletotrichum falcatum, Went, is simp'y one phase in the life history ot Trichoy. 
pharia sacchari, Mas.” Thus one is fully justified, until further evidence is adduceg, 
in repudiating the suggestion that the organism or so-called “ parasite ’ whose presenve 
is associated with these two cane maladies are some condition of a single fungus, and 
not of perfectly distinct ones. 
The relation between this fungus of Went’s ‘ Rod Snot,’ and the plant within 
whose tissues it takes up its abode, has been made the object of experimental 
investigation at the hands of the Java expert, Professor Went. As the outcome of 
inoculating healthy canes with pure cultures of the fungus, he concludes that it is the 
cause of the disease; but that, it being primarily a fungus developing on non-livin 
vegetable matter, it can only establish connection with the cane-plant, where the cells 
composing the tissue of the latter have been first injured or killed as at the site of 
some wound, but that when once this connection has been established, it can invade 
the plant generally, producing the characteristic red-tissue discolouration and othey— 
phenomena of the disease; in fact, that it is a wound parasite. He also states with 
reference also to its occurrence in Java, that in districts where the Red Disease is stil] 
unknown its fungus, Colletotrichum falcatui, lives on dead cane-leaves, and therefore 
as au saprophyte. He also mentions that the special injuries that are availed of by 
this wound parasite associating itself with the living tissue, are more especially the 
tunnellings of boring insects. ‘This has also been shown to be the case iy 
Bengal, Lieutenant A. T. Gage having recorded that in fifty-eight out of sixty. 
five instances of diseased canes in which it occurred, the Pinhole Beetl: 
Borer (Xylehborus, sp.) was met with. Went also states that in a planta. 
tion where sugar-cane is subject to the presence of borers, and “Rod Snot” | 
disease once appears, if will very soon become widely disseminated amongst 
cane that is as yet unvisited by it, and so occasion much damage; also, in view of this 
contingency, that whenever on a field of cane the presence of the disease has been 
detected by splitting open some of the s‘alks (when the red discolouration will be 
revealed), the immediate crushing of the cane will result in loss being obviated, 
Insect borers of sugar-cane of more than one kind are to be met with in Queensland, 
as you are aware, as well as Java, and, possibly, one of the Pinhole Borers also, 
belonging t» the genus Xy/eborus. 
Went has stated, insomuch as the special fungus now referred to is generally met 
with, not as a parasite, but supporting itself upon dead plant tissue, “its mere 
presence on diseased cane (where, it may be, it may also manifest its occurrence by 
occasioning red tissue discolouration—H.'T.) is no evidence for its being the cause of the 
disease.” (Annals of Botany, vol. x., 1896, p 588.) This is a consideration that 
the investigator must not lose sight of when manifestations in this state of cane 
disease, in which the presence of Co/letotrichum is a conspicuous feature, are being 
inquired into. 
HOW A TENDENCY TO DISEASE MAY BE BROUGHT ABOUT. 
Now. in view of these facts relating to the occurrence of two potential disease- 
producing fungus organisms in Queensland, a certain emphasis has been laid wpon” 
the fact that under general circumstances they are saprophytes, and subsist wpon 
dead cane, and possibly other vegetable matter also. It may again be remarked that 
there are grounds for concluding that such organisms as these, whose parasitism 
may be described as merely facultative, can only establish injurious relations with 
the sugar-cane when this is the victim of certain conditions, the existence of which 
is, however, a matter of inference only, in the absence of special manifestations. 
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