REVIEW.

New Zealand Journal of Agriculture, Volume XL, Issue 6, 20 June 1930, Page 429

REVIEW.

Fungous Diseases of Plants, Jakob Eriksson (2nd edition, English translation by W. Goodwin); vi J-526. pp., 399 illustrations. Bailliere, Tindall, and Cox, London, 1930. £1 15s. net.

This book covers the major bacterial and fungous diseases of agriculture, horticulture, and forestry. Diseases are grouped according to the family or order to which the causal organism belongs, and ’under each is given brief notes on the symptoms, life-history, and remedial treatment. Symptoms of many diseases are illustrated by half-tones or line drawings, and fructifications of many of the pathogens are shown by line drawings.

As a general text-book purporting to cover modern knowledge of plantdiseases this work is most disappointing. The arrangement of diseases under groups of pathogens makes the book difficult to handle (the host index in the appendix being of little aid) ; the text is often archaic, and appears to have undergone little alteration since the first edition was published in 1912, for one gains the impression that the author has disregarded most recent literature. An annoying feature is the frequent reference in the text to authors not cited in the bibliographies following each disease.

The author persists in his mycoplasm theory, and extends it from the rusts to cover late blight of potatoes (Phytophthora infestans') and downy mildew of spinach (Peronospora. Spinaciae}, and, unconsciously perhaps, permits it to permeate the whole work ; and this despite the constant criticisms to which the theory has been subjected from the time of its promulgation (1897), and failure of any one else to obtain evidence in its support. He. still adheres to his earlier views concerning species in the rust fungi, as in the book one finds reference to Puccinia Phleipratensis, P. bvomina, P. Symphyti-bromorum, P. holcina, P. Triseti, P. covonifeva, P. Poae-alpinae, &c. Some of these are merely biologic forms of the common cereal rusts, and others are recognized only by the author.

That the author’s taxonomy requires revision is indicated by the use of names now obsolete, such as Ustilago nuda, Puccinia simplex, Uromyces caryophyllinus, ' Phragmidium subcorticium, Polyporus (for Pomes), Phoma olevacea, P. Napo-brassicae, Sporodesmium Solani, Rhizoctonia violacea, Mycosphaerella pinodes, &c.

In the sections dealing with control are many recommendations that are quite impracticable, others erroneous, and others again apparently suggested because of the author’s persistence in his mycoplasm theory. Thus Uspulun or Germisan is recommended as a substitute for hot water in the control of loose-smut of wheat and barley ; barberry eradication is considered to be of doubtful value ; removal of grasses in the vicinity of cereal crops is recommended in the control of cereal rusts ; avoidance of seed from infected crops appears to be a favourite recommendation ; while for the control of leaf-curl of peach-trees painting the trunks with a mixture of clay, dung, lime, and carbolineum is advised. One can picture, too, the conscientious farmer following instructions for the control of Sclerotinia sclerotiorum, down on his knees in a 10-acre field of Jerusalem artichokes carefully picking up by hand all sclerotia ! G H C

Noxious Weeds. Two plants have been added to the Second Schedule of the Noxious Weeds which comprises noxious weeds when so declared by a local authority—namely, stinking mayweed (Anthemis co tula) and convolvulus (Convolvulus arvensis and C. sepium, both species). -■ ...