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Within the next few years the question of profitableness will be cleared up. In the meantime it is certain that for the shallow and moderately deep ploughing of the light and medium soils so prevalent in Germany motor ploughs assist very materially by the careful and seasonable tilling which can be done with them, and in overcoming the difficulties which the unfavourable labour conditions oppose to the increase of the total yield of crops.

Report on the Diseases observed at the Phytopathological Laboratory of the National Museum of Rio Janeiro

by

ANDRÉ MAUBLANC,

Chief of the Laboratory

With the exception of some investigations concerning the most important economic plants, chiefly coffee, it may be said that phytopathology has been hitherto much neglected in Brazil. Certainly some naturalists have collected abundant material which allowed an idea, though a somewhat incomplete one, to be formed of the especially rich mycological flora of the country; but this material has for the most part been studied in Europe, and the specialists who dealt with it could not direct their researches beyond the morphology and the system of the fungi on cultivated and spontaneous plants.

Since its foundation, still quite recent (1910), the Phytopathological Laboratory of the National Museum of Rio Janeiro has been obliged, through lack of proper installation, to limit its efforts to the scientific determination of the diseases which it examined; but the definitive organization of this Laboratory, which is now an accomplished fact, will allow of more exhaustive phytopathological researches being made and of dealing with biological questions, which are the most important for the practical conclusions which may be drawn from them as to treatment.

Still, even now it appears to me to be interesting to state briefly which are the most important and most widely spread parasitic fungi on cultivated plants in Brazil, almost exclusively in the Southern States : from Rio de Janeiro to Rio Grande do Sul, the only region from which the Laboratory has sufficient material. This information may be of real importance, as it is only by the comparison of similar statistics published in the various countries that an exact knowledge will be acquired as to the distribution of the principal diseases, and this seems indispensable, if it is intended by an international understanding to arrive at legislation capable of reducing to a minimum the danger of introducing into a given region diseases which are still unknown to it.

COFFEE. The coffee plant, which is of capital economic importance to Brazil, is, especially in the State of São Paulo, almost immune from plant parasites of any importance. Certainly the leaves present some spots caused by various fungi : Cercospora coffeicola Berk. and Cooke (the most frequent species), Sphaerella Coffeae Noack, Colletotrichum coffeanum Noack, Stilbum flavidum Cooke, and Phyllosticta coffeicola Spag.; these two latter are confined to some moist localities of the coast belt and are unknown in the great plantations of the interior. None of these fungi are really dangerous and their effects can not be compared to those caused by unfavourable climatic conditions and especially by the cold winds from the south, which sometimes lead to the drying up of the branches. Some cases of rot are also to be mentioned; they are due to a fungus which has not yet been determined, and have been found in the State of Minas Geraes; but they are purely local cases.

SUGAR CANE. This crop, also very important, does not suffer from dangerous diseases in Brazil, at least in the greatest number of plantations; only rare cases can be mentioned of the appearance of disease due to Colletotrichum falcatum Went. (morve rouge) and to Thielaviopsis paradoxa (de Seynes) v. Höhn (pineapple disease). Leptosphaeria Sacchari v. Breda de Haan and Phyllosticta Sacchari Speg. cause only insignificant injury to the leaves.

TOBACCO.

Tobacco leaves often bear spots due to Cercospora Nicotianae Ell. and Ev., and also other spots the causes of which are not yet well known: they do not seem to be due to parasites and are often designated by the vague name of "rusts ".

MAIZE. Only maize rust (Puccinia Maydis Ber.) has to be mentioned, and it is of no great importance.

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MATÉ. A great number of fungi, especially on the leaves, but seemingly not dangerous, have been noticed by Spegazzini on Maté (Ilex paraguariensis), a plant of the greatest economic importance in the south-western States of Brazil. I have recently had occasion to study the leaves of this shrub, on which I have recognized the presence of the following species Phyllosticta Mate Speg., Cercospora Mate Speg., Colletotrichum Yerbae Speg. and Pestalozzia paraguariensis Maubl. (description not yet published).

RICE. Only Piricularia Oryzae Cav. is to be named.

COTTON. The leaves of cotton are frequently attacked by Uredo Gossypii Lagerh. and Cercospora gossypina Cooke. A more serious disease is "fruit rot"; it is imperfectly known and doubtless due to the action of bacteria introduced by the punctures of insects.

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VINE. In the south of Brazil, vines have suffered from the following diseases: Cercospora viticola (Ces.) Sacc., the most frequent species, and when widely spread producing a serious disease; anthracnose (Gloeosporium ampelophagum [Pass.] Sacc.), very frequent; powdery mildew (Oidium Tuckeri Berk.); mildew (Plasmopara viticola [Berk. et Curt.] Berl. et de Tori); Coniothyrium Diplodiella (Speg.) Sacc., form on leaves

hitherto very rarely observed; Septoria ampelina B. et C.; Colletotrichum ampelinum Cav.; Pestalozzia uvicola Speg.

WHEAT. On wheat, in the south of Brazil, smut (Ustilago Tritici Jens.) has been reported, and especially the rust, which, according to the samples received, is due to Puccinia glumarum (Schm.) Eriks. et Henn.; in one case only was I able to ascertain the presence of Puccinia graminis Pers. occurring with the preceding species.

FRUIT TREES.

up to the present:

The following list includes the parasites observed

Guava tree: Puccinia Psidii Wint. (on leaves and fruits); Gloeosporium Psidii Delacr.; Pestalozzia Psidii Pat.

Mangoes Gloeosporium Mangae Noack. (on the fruit); Gloeosporium Mangiferae Hern. (on the leaves).

Bananas Gloeosporium Musarum Cooke and Mass.

Citrus fruits, various: gummosis; Colletotrichum gloeosporioides Penz.; Septobasidium albidum Pat. (or the excreta of scales).

Jabotica beira (Myrciaria Jaboticaba): Uredo Rochaei Puttem, and Oidium Rochaei Putt.

Fig: Uredo Fici Cast. and Phyllosticta sycophila Thüm.

Papaw Sphaerella Caricae Maubl. (very frequent in its conidial form Asperisporium Caricae [Speg.] Maubl.).

Cambuca (Eugenia edulis): Uredo Cambucae Henn.

Peach: Monilia fructigena Pers. and Cladosporium carpophilum Thüm. Apple Gloeosporium fructigenum Berk. and Macrophoma malorum (Berk.) Berl. et Vogl. (on fruit).

Pear Gloeosporium fructigenum Berk.

Quince Gloesporium fructigenum Berk.

Plum Puccinia Pruni-spinosae Pers.

Japanese plum (Prunus trifolia): Gloeosporium fructigenum Berk. and Monilia fructigena Berk.

VEGETABLES.

Cauliflower Alternaria Brassicae (Berk.) Sacc. This species, studied by M. Pattemans, has caused serious damage, attacking the leaves ard the flowers in the State of Rio de Janeiro.

French Beans: Colletotrichum Lindemuthianum (Sacc. et Magn.) Br. et Cav.; Uromyces appendiculatus (Pers.) Link; Oidium erysiphoides. Fr.; Isariopsis griseola Sacc.

Peas Oidium erysiphoides Fr.

Tomatos Septoria Lycopersici Speg. (very frequent species).
Carrots Macrosporium Carotae Ell. et Langl.

Asparagus Cercospora Asparagi Sacc.

Celery Cercospora Apii Fres.

ORNAMENTAL PLANTS.

Roses: Phragmidium tuberculatum Muell.; Sphaerotheca pannosa (Wallr.) Lév. (conidial form); Marssonia Rosae Br. et Cav.; Cercospora rosicola Pass.

Carnations: Heterosporium echinulatum (Berk.) Cooke.

Dahlias Oidium sp.

Begonia Rex: Oidium Begoniae Puttem.

OAK. Oidium alphitoides Griff. et Maubl.

The appearance in Brazil of this dangerous parasite is interesting; it dates from the month of August 1912, when oak mildew was observed by M. Puttemans in the gardens and parks of São Paulo; semewhat later I recognized its existence at Campinas and since then the disease has made much progress.

Lastly fumagine is very widely spread on the leaves of a great number of plants (Aurantiaceae, coffee plants, etc.), where it is the consequence of the attacks of scale insects and aphides.

The preceding list does not claim to give a complete picture of the fungus diseases existing in Brazil; it has been drawn up with the assistance of the documents possessed by the Phytopathological Laboratory of the National Museum, leaving out those species which do not present any practical interest, either because they attack wild plants, or because they do not cause any serious injury to cultivated plants. On the other hand a number of specimens preserved in the collections of the Laboratory have not been comptetely studied owing to want of time; this study is being pursued at present and it may already be stated that a great number of parasites — the description of many of them has not yet been published might be added to the above list.

Further, for instance at São Paulo, several fungi have been reported, some of them injurious to cultivated plants (Phytophthora infestans, Plasmo para cubensis, etc.), which do not appear in the above list. It would have been easy to lengthen it with the help of bibliographical data, but I wished to mention only those diseases which had been observed at the Phytopathological Laboratory of the Museum, and the specimens of which are preserved in its collections, thus allowing the determinations to be controlled.

SECOND PART.

ABSTRACTS

AGRICULTURAL INTELLIGENCE

LEGISLATIVE

AND ADMINI-
STRATIVE
MEASURES

624

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GENERAL INFORMATION.

Project Relating to an Official Register of Selected Plants in Hungary. Köztelek, Year 23, No. 32, pp. 1153-1155. Budapest, April 26, 1913.

M. Emile Grabner, director of the Royal Hungarian Institute for the selection of Plants at Magyaróvár laid stress, in the report which he presented to the committee of the above Institute, upon the urgent necessity for a regulation dealing with the systematic development of the selection of agricultural plants. Although in Hungary plant selection has been practised for a number of years, it is only during the last seven years that it has met with any success. As the first step to promoting systematic plant selection is the encouragement of the agriculturists engaged in the task, M. Grabner suggests for this purpose the establishment of an official register of the plants selected in Hungary; the chief heads of the project are as follows:

1) The objects of the register are on the one hand to protect the rights of Hungarian agriculturists engaged in selection and to prohibit the illegal sale of varieties which have been improved by thein, and on the other to afford every guarantee to the purchaser of the strict selection of the variety which has produced the seeds he wishes to buy. This guarantee does not extend to the quality of the seeds (e. g. to their power of germination), nor to the value of the crop, but exclusively to the identity and purity of the variety.

2) The register will comprise field crops (cereals, root crops, oil crops, industrial crops and forage crops) systematically selected in Hungary. In the case of autogamous plants, only those can be inscribed which have been obtained from pedigree selection, or by the hybridization of pedigree varieties; in that of allogamous plants, only those are admissible which have been obtained in the same way, or by selecting families; but if this method is employed, it is necessary to prove that the parent plants were selected according to the revision and annual classification of the register. It is necessary, in the case of new varieties obtained from others already

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