30 



THE AORICULTUKAL NEWS. 



Jani'auv 18, 1913. 



FUNGUS NOTES. 



A DISEASE OF TANIAS. 



Information is given in the Joitri'al of tlu Jamaica Ayri- 

 ctiltwa! Society, for November 1912, in regard to a disease 

 of the Tania, or C'ocoe, as it is called in Jamaica, which 

 appears to be widely distributed in that island. It seems 

 that some varieties of tanin, for iij.-Ntance 'Sinkil', 'White Jack' 

 and 'Bamboo', are particular}- su.sceptible: whereas the tania 

 known as 'Sally' is very rarely attacked, even when planted 

 in infected soil. 



The disease has been investigated by Ashby, recently 

 Bacteriologist and now Microbiologist to the Jamaica Depart- 

 ment of Agriculture. His account of the disease is as follows: — 



'The disease is the dry rot caused by a fungus not 

 described by mycologists elsewheie. I have only found it on 

 samples of the Commander variety of cocoe from several 

 places in Portland and St Mary. The name I have given to 

 it i.s I/orinixciinn ro/orasiae. The fungus enters the water- 

 conducting system and stops it up, in part causing an effect 

 resembling drought; in time the water-conveying strands turn 

 brown and give the characteristic appearance to the cocoe 

 when it is split open. The tissue shrinks and split.s internally, 

 and when the split extends to the surface, insects, worms and 

 other fungi gain entrance and increase the rot. 



'The parasite can only gain entrance through a wound in 

 root or tuber, if not already present in the ".seed" or "eye" 

 (an analogy from the "Irish" potato). 



'The disease gains entrance then: — 



(1) From the seed used for planting in which it is 

 present invisibly to the naked eye. 



(2) By infection of the fresh cut surface of the "seed''. 



(3) Through any wound of root or tuber, however small. 

 'Xo. (1) is a very general source of infection. The 



fungus extends in the water conducting strands much beyond 

 the parts which become brown: if a diseased cocoe is used 

 for planting, no matter how carefully the visibly diseased 

 parts may be cut away, the fungus may still be present in 

 the apparently sound portion and from this, extend into the 

 buds which grow into the new plant. It is also evident that 

 a cutlass or any knife which has been used in cutting up 

 diseased cocoes will infect the surface of an otherwise sound 

 "seed'' and also propagate disease 



'I believe that this disease has spread over large areas, 

 and is still extending, as the result of the use of diseased 

 "seed". 



'With regard to (3), land which has raised a succession 

 of more or less diseased crops of "Commander' will be 

 saturated with the disease which is preserved in every 

 fragment of decaying root and tuber 'eft in the soil; a wound 

 on root or tuber caused by insects, grubs, or worms, however 

 small, would then make the chance of infection strong. In 

 dealing with the disease two principles must be ob.served 

 therefore: — 



(1) Xever plant from diseased material, no matter how 

 slight the visible attack. 



(2) Cease to grow the variety in question on land in- 

 fected by disea.se; this must hold until experiment has shown 

 how long the fungus retains its vitality in the soil.' 



It might be added that Massee ascribed the cause of 

 C' locasia disease of Tanias to Fei-onof/iora iricliotnmi 

 (Mass.). In the early stages of this disease a tuber when cut 

 across shows ^ number of yellow dots cr points which corre- 

 spond in position to the vascular bundles; these become 



darker in colour as the disease progresses and finally the 

 entire substance of the tuber, with the exception of a thin 

 peripheral portion, becomes blackish in colour and decayed. 

 Although these symptoms possess points in common with 

 those described by Ashby, it is quite possible that two 

 diseases exist and tha,! each is caused by a different fungus. 



^EW SOURCES OF PAPER. 



Of all raw material, a new fibre is perhaps the most 

 diliicult to introduce to the market; it has to be as good and 

 as cheap as (often better and cheaper than) one of the old 

 fibres, and it must be produced on a sufficiently large scale 

 to make its supply uniform. In the case of a fibre possessing 

 exceptional qualities the difficulties attending its commercial 

 introduction arc reduced, and this applies to some new 

 sources of paper which have recently received attention in 

 the Kcir null it in, Xo. 'J, 1012. 



Early last year, Messrs. Clayton Beadle and Stephens 

 drew the attention of Kew to the value of Hedyrhium 

 i-oroiiari 111)1 as a source of material for paper-making. This 

 plant, a member of the Xatural Order Zingiberaceae, to 

 which ginger belongs, is a native of India; but is also 

 recorded from Central America, the West Indies, New 

 Zealand, Mauritius and West Africa. It flourishes only 

 under tropical swamp conditions, and large areas covered 

 with this plant are to be found in Brazil. The plant is 

 characterized by the horizontal tuberous rootstock which 

 bears erect elongated leaf stems 3 to 5 feet high by 'l to li 

 inches thick. The atrial portions of the plant are not unlike 

 those of the maize in general appearance. After cutting 

 down the stems it is found that four to five months must 

 elapse before a fresh growth of stems is made. The specific 

 characters of the plant are: Inflorescence ellipsoid or ovoid; 

 3 — 5-flowered bracts which are densely imbricate (overlap- 

 ping) in 5 — S-spirals. Staminodia (barren stamens) oblong-" 

 lanceolate, white. Labellum (strongly developed petal) 

 widely obcordats (inverted heart-shaped) white, with yellow 

 sometimes near the base. Filament white. 



Having satisfied themselves as to the good qualities of 

 Hedychium fibre from dried material received from Brazil, 

 ^lessrs. Clayton Beadle and Stephens matle further investiga- 

 tions with fresh green material obtained from growing plants 

 at Kew. In a letter to Kew, ^[es.•rs. Clayton Beadle and 

 Stephens wrote: 'I^apcrs produced from this fibre have even 

 greater tensile strength than the strongest manila papers 

 produced. The strongest manila papers have a strength of 

 6,000 to 7,000 metres ''breaking length . Tliis paper has 

 from 9,000 to 10,000. Its elasticity and folding qualities 

 are exceptional. Moreover, it can be made to bear ink and 

 jiossess parchment qualities without any sizing or other 

 special treatment. 



'The reason for this we find to be due to the presence of 

 the cells associated with the fibre, which are of a semi-gela- 

 tinous nature, when chemically treated, and dry into the 

 interstices of the paper ami produce natural parchment.' 



The following is an extract taken from a paper recently 

 l)resented to the Eighth International Congress of Applied 

 Chemistry by Messrs. Clayton Beadle and Stephens 'We 

 draw attention to this fibre as we believe it may become of 

 great industrial importance to the paper trade. Where 

 circumstances are congenial to its growth the plant spreads to 

 the exclusion of all other vegetable growth by means of its 

 rhizomes so that it can be harvested at least once a year, 

 producing a heavy crop. It is an ea.sy pulp to manipulate. 

 It is caj able of producing a paper of exceptional strength and 



