A little-known world of plants
Concerning sick trees
6 useful forestry titles from FAO
Underexploited tropical plants with promising economic value
Report of an ad hoc panel of the Advisory Committee on Technology Innovation Board on Science and Technology for International Development, Commission on International Relations, Report No. 15. National Academy of Sciences, Washington, D.C., 1975. 188 p. Postage and handling charge $0.50 in the United States and $2.50 elsewhere.
This book is about a little-known world of plants, both wild and domestic, the variety of which is staggering. A variety of considerations weighed in the selection of plants described. These included their potential as food for humans, as animal forage, as industrial raw material, the ability to grow in the tropics, and multiple properties enabling several useful products to be obtained from a single plant. Medicinal plants and timber species are not included. Economic considerations for selecting the plants were relegated to the background, except in the most informal and subjective manner, because of the difficulty in determining future costs and benefits of exploiting these plants in vastly dissimilar environments.
Each of 36 plants is presented in a separate chapter giving a short description and touching on economic importance, limitations and special requirements and the research needs. The plants range from little-known to familiar species whose full potential has yet to be realized. The choice of species is obviously subjective, a fact which the authors themselves admit. It leans heavily toward Latin America. Asia and Africa abound in plants that have similar potential but have not been given adequate coverage, which they deserve. The plants have been grouped according to the use the major economic product they yield is put to, as:
(i) cereals and pseudocereals,
(ii) roots and tubers,
(iii) vegetables,
(iv) fruits,
(v) oilseeds,
(vi) forage crops, and
(vii) other uses.
The first group comprises plants yielding nutritious grains, and in some cases the entire plant makes an excellent hay. Echinochloa turnerana and Zostera marina are of special significance in that the former needs a single deep watering to develop from germination to harvest and as such is most suited to arid regions, while the latter plant is one of the few that grows fully submerged in seawater. Using the sea to grow grain is a novel and highly speculative concept and Zostera marina holds potential as a food crop.
The next group comprises plants that yield edible roots and tubers which are an important carbohydrate foodstuff, and may be boiled, baked or fried in oil or used as ingredients in stews. Colocasia species have a particular potential for marshy waterlogged regions and also coastal and salinified regions.
Grouped under vegetables are some interesting plants such as Psophocarpus tetragonolobus and certain plants yielding "palm-hearts." The first plant yields edible seeds, pods and leaves with usually high protein levels and is possibly the tropical counterpart of the soybean. The "palm hearts" (harvested from Enterpe, Bactris, Cocos, Aerocomis palms) are a tropical delicacy. There is an ever increasing demand for expensive exotic foods throughout the world and the demand for "palm hearts" exceeds supply.
XIQUE-XIQUE (Cerrus horridus) CACTUS FOUND IN NORTHEASTERN BRAZIL, PEELED FOR ROASTING AND EATING
Forming the fruit-group are species such as Garcinia mongostana, Citrus grandis and Annona muricata which yield highly flavoured fruits and have export potentials. Guilielma gasipaes yields a chestnut-like fruit, which is considered the most nutritionally balanced of tropical foods. This tree is eminently suited to wet tropics and, once established, requires little care and yields well.
Plants producing oilseeds are wide and varied. They include palms, desert plants and perennials. Orbignya speciosa seeds produce oil similar to coconut oil, but the labour required for seed collection and the unusual hardness of the endocarp are obstacles to its increased use. Simmondsia chinensis deserves special mention in that its seeds contain liquid wax that has impressive industrial potential.
Among the forage-yielding plants, Acacia albida and Prosopis tamarugo deserve special mention. The former is verdant with foliage and fruit during the dry season and its leaves and pods are often the only fodder available at that time. The latter species, native to the Atacama Desert in Chile, grows through a layer of salt, sometimes a metre thick. In fact there are few useful plants that can survive the extreme conditions of the plants' native habitat.
Included in the last group are palms, grasses and algae that yield a variety of products such as fibres, wax, protein, starch and rubber. Parthenium argentatum deserves special mention. All parts of the shrub contain a rubber, virtually indistinguishable from natural rubber from Hevea trees. It is a potential source of rubber for arid lands, but acquisition of processing technology is a major hurdle to its wider exploitation. Mention may also be made of Spirulina blue-green algae, which could be used as food for human consumption. They grow in brackish and alkaline waters and are rich in protein and vitamins.
One of the most important features of this book is that it brings out clearly the limitations and special requirements of each of the species it describes, factors which have been impediments to the realization of their full potential. These impediments fall into specific categories.
I. Lack of adequate agronomic and/or horticultural knowledge, such as absence of improved varieties for sustaining high yield, the number of years required for the plant to mature and yield the raw material, inadequate information concerning conditions governing growth and yield, susceptibility and/or resistance to diseases, and lack of vegetative propagation.II. Technical problems, such as those requiring tedious manual labour and long hours of work in an uncongenial environment or problems of inadequate processing technology.
III. Nutritional limitations, such as insufficient information on nutritional factors, toxicity, palatability, and inadequate food technology.
IV. Economic factors such as low financial return to growers and producers.
V. Environmental consequences such as the effects of introducing plants to new regions where they may become a weed; serve as hosts to parasites and predators or become overly competitive with other plants.
Given concentrated research, the above-mentioned limitations could be largely overcome and many an underexploited plant could follow the developmental course of the soybean, which was considered an oddity at one time. This would make developing countries more productive and provide significant job opportunities. Export of processed goods would encourage setting up of subsidiary industries.
This is a book which is not only informative but makes interesting reading for the general reader concerned with plants as well as the specialist. It is also well illustrated, with many carefully selected photographs.
P. ARGAL
Forest Pathology - principles and practices in forestry
by B.K. Bakshi. Published by the Controller of Publications, Delhi. Printed at the F.R.I. Press, Publicity and Liaison Branch, Forest Research Institute and Colleges, Debra Dun, India, 1976. 400 p. Illustrated. Price Rs 21, UK£2.45, US$7.56.
This book is a welcome contribution to a subject of wide interest and importance. There has been a general lack of consolidated accounts of diseases of forest trees in the Indian subcontinent and Dr. Bimal Kumar Bakshi, forest pathologist and director of biological research at the Forest Research Institute and Colleges, Debra Dun, helps to fill this void.
The volume is divided into three parts. Part I takes up general principles of forest pathology; Part II, which accounts for the major part of the text, deals with diseases of indigenous as well as exotic forest tree species of the region, and Part III covers microbial degradation of wood.
The book opens with a short description of the forests in India and proceeds to discuss the causes of diseases in plants, divided into two categories - parasitic and physiological or physiogenic disorders.
There is a useful chapter on broad principles of forest disease control. It is noted that prevention and control of forest tree diseases are all too often ignored because, in general, forest stands have a relatively low value per unit of area, as compared to agricultural crops.
However, intensive control measures are economically justifiable in nurseries and plantations where the crops have a high value.
The intrinsic value of this book lies in Part II which gives a comprehensive account of recorded diseases of forest tree species of the Indian subcontinent, both indigenous and exotic, including diseases that plague these trees in other countries. For exotic conifers which are mostly in the trial stage in India, diseases recorded in India only have been described.
The author has given a host-wise and not pathogen-wise account of the tree diseases commencing with diseases that are rampant in economically important timber species. The discussion invariably begins with a short account of silviculture and management practices of the species and is followed by an account of range of distribution of disease, nature and extent of infection, damage and symptoms. Finally, measures for controlling the disease are indicated. For indigenous species of lesser economic importance some of these details are omitted. Discussion of pathogenic diseases precedes that of physiological disorders, the former receiving relatively greater attention, presumably because they have been studied at some length and also because the aggregate damage they cause to the forests is considerable.
The diseases treated here are as varied as their causes and are major biological determinants of forest productivity. Among the diseases dealt with are disease of Santalum album, which yields one of the costliest woods in the world and whose very existence is now threatened, Ganoderma root rot of Acacia catechu and Dalbergia sissoo, Polyporous shoreae root rot of Shorea robusta, pink disease of Eucalyptus, blister rust of Pinus wallichiana, Fomes annosus root and butt rot of Cedrus deodara, damping off disease of seedlings in nurseries, cankers of Cupressus and Juniper species and woody gall of Terminalia belerica. Also covered are physiological disorders such as water blister of Tectona grandis, gummosis of Eucalyptus species and large-scale dying of Shorea robusta, to name a few of the more common and destructive diseases. These diseases have been discussed at varying lengths depending on their relative importance, but there is, quite naturally, a tendency on the part of the author to emphasize diseases with whose investigations he has been associated or of which he has personal experience.
A useful reference work distinguished by a lucid presentation, the book is furnished with clear, informative and well-chosen illustrations. However, in the text there are avoidable repetitions that are distracting and prevent smooth reading. The author also pros vices an excellent bibliography of puts fished literature on plant pathology and allied subjects and makes copious references to these sources in the text.
P. ARGAL
Unasylva manuscript style Unasylva An international journal of forestry and forest industries, is published quarterly in English. French and Spanish editions. Language and writing style Manuscripts are accepted in English, French or Spanish. Well-organized and clearly written manuscripts not only help to communicate ideas and information to the reader, but they facilitate editing and translation Manuscript preparation Manuscripts should be in duplicate typewritten double-spaced on one side of the page only and with wide margins. About 250 words to a page will simplify word-count estimates. It should be possible for us to make clean easily read photocopies from any manuscript, therefore please use a new typewriter ribbon. The first page should have in the upper right hand corner the authors name and address, the date and the number of words in the main text, not including words in tables, figures, captions or titles. Subsequent pages should have only the author's in advance author's name in the right-hand corner. Metric system All measurements should be in the metric system. Tables, figures, drawings Tables, figures and drawings of any kind should each be on a separate page and numbered to correspond to their points of reference in the text. They should never be pasted into the body of the text. They should be as clear and simple as possible. Only essential tables and figures should be included and all should be identified as to source. Photographs Unasylva uses black-and-white photographs. We prefer good quality black-and-white prints 18 x 24 cm (8 x 10 In) on glossy paper. If a diapositive colour-slide is of high quality we may be able to make a copy negative from it and a good quality black-and-white photograph, but we prefer not to have them. We will make every effort to return colour slides and black-and-white negatives but we cannot guarantee return. Black-and-white prints are not returned. Footnotes and references Footnotes and references should be listed on separate sheets at the end of the manuscript. Footnotes should be kept to an absolute minimum and we prefer none. References should be strictly relevant to the article and should also be kept to a minimum. For style of references please see examples in the magazine. Length Long articles are 3 000 to 4 000 words, and short articles are 750 to 2 000 words. Republished articles Unasylva prefers original articles but does not rule out reprints, especially where there is the possibility of exchanging views and developments of basic importance in forestry and forest industries between readers in developed and developing regions of the world or where language considerations are involved. Queries in advance We welcome letters from writers suggesting ideas and subject matter for pro-posed articles. They usually result in articles of a higher quality and in a saving in writing and editing time. Who are file readers? Unasylva subscribers in some 135 countries fall into the following broad categories: -Government officials, in particular the executive level of national forest services, wildlife departments and national parks. This also includes delegates and missions attached to the United Nations and its specialized agencies and staff members of international organizations dealing with forestry, environment, forest industries and trade. -Forestry schools and institutes, both through their libraries and subscriptions to individual staff members. -Forest industry companies dealing with services for forestry, companies dealing in forest products. -Individual professional foresters, especially those concerned with international forestry. -Editors of professional and trade journals dealing with forestry, forest industries and environmental conservation. |
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