The Scope of the Biologist in Plant Research Institutions in New Zealand

by F. R. Callaghan, Department of Scientific and Industrial Research, Wellington.

The student of biology must at times ask himself the question “To what use am I going to put my biological studies in my vocation in life”? It is true that a knowledge of biology may be regarded as an essential to a sound education. Those who propose to enter the teaching profession will require it for the instruction of their pupils. There are others, possessed of the gift and the flair for undertaking research, whose inclinations may direct them into the fields of biology. What opportunities are there in New Zealand for those wishing to engage in biological research? What is the nature of the biological research now in progress in New Zealand, and where is such work proceeding at the present time? This article will attempt to set out briefly the answers to those questions insofar as the plant kingdom is concerned.

The Plant Diseases Division in Auckland under the direction of Dr. G. H. Cunningham is concerned, as its name implies, with the study of plant diseases. In addition, this Division engages in a number of page 6 investigations relating to the Fruit Industry and to the protection of timbers from the ravages of insect and fungoid pests. Plant pests are of the utmost importance to the economic development of the Dominion's rural industries. Every crop is liable to infection by some disease caused by insects, fungi, bacteria, or virus. Those with even a limited acquaintance with the fruit industry will know how much time, effort and money the orchardist has to expend in the application of sprays, and in other measures, to check the ravages of various plant diseases. The research work at the Plant Diseases Division calls therefore for skilled biologists, especially for plant mycologists, bacteriologists, virologists and entomologists. Every disease has to be understood thoroughly before control measures can be devised, and what is of equal importance, the relation of the disease to its host plant has to be understood. Biologists working in collaboration with chemists devise suitable sprays or dusts for control of the pest and these are tested out thoroughly under field conditions. As a consequence of the research work done by the staff of this Division, many serious plant diseases have been brought under control and a few may be quoted—loose smut of wheat and barley, bacterial blight of plums, black spot, and corky core of apples.

However, despite these results, the fight against plant disease must continue, for many still remain unconquered, while new ones regularly appear. The field for the research biologist with inclinations towards mycology, bacteriology, virology, entomology and taxonomy appears likely to offer prospects of an abundance of interesting problems.

At Palmerston North, in close proximity to Massey College, the Grasslands Division, directed by Mr. E. Bruce Levy, is located. As its name signifies, this Division is concerned with research into pasture problems, and as pasture constitutes New Zealand's most important crop it will be realised that it is not devoid of problems full of interest for the biologist. Nature had clothed a great part of New Zealand with native grasses, which though good in themselves, the farmer has endeavoured to improve by the introduction of other species with which he was accustomed in the Northern Hemisphere. The result is that New Zealand grassland is a mixture of native and introduced species of pasture plants, each of which has thrived differently according to the climate, soil, or management conditions to which it has been subjected. It therefore presents a remarkable field for study by the ecologist who can engage in pasture survey work, in the interpretations of the reasons which lead to the dominance of certain species in certain localities. The work has very considerable economic and national interest, as scientific ecology is a great guide in deciding what vegetation should occupy any special area or what steps should be taken to use various types of vegetation for soil conservation purposes.

It has been shown that most pasture plants are capable of being improved by selection and breeding. Much of New Zealand's promin- page 7 ence as a grassland country can be attributed to the use by its graziers of improved strains of ryegrass, clover and cocksfoot, developed for the most part by the Grassland Division. Work, however, in this field is only in its initial stages and the scope for its extension is considerable.

Pasture is grown for stock to consume either in the green stage, or as ensilage or as hay. The animal converts the substance of pasture into milk, meat, wool and bone. It is important that this conversion be carried out economically insofar as both pasture and animal are concerned. Studies of the nutritive value of pastures at various stages of growth, of ensilage, of hay, using animals for making these tests, checked against those made in the chemical laboratory, are therefore made. The influence exerted by the grazing animal upon pasture composition is all important to ascertain the best use which can be made over a long period of any pasture and this leads to further studies associated with pasture establishment, pasture management and the use of supplementary fodders. All this work is of interest to both plant and animal biologists and its results all have bearing upon pasture utilisation. Soil and climatic conditions greatly favour pasture production in New Zealand, but there is a vast field of unexplored problems ahead for the plant biologist, especially those interested in ecology, genetics, plant breeding and plant physiology.

The Botany Division has its headquarters in Wellington, and is under the direction of Dr. H. H. Allan. This Division services the other Divisions and deals with an extremely wide range of botanical problems which lie outside the scope of those Divisions. For example, it is responsible for phormium research and for research dealing with seaweeds, and with the major weeds such as ragwort and nassella tussock. During the war it investigated the possibility of growing locally medicinal plants such as belladona, opium, Datura, and their processing for the production of various drugs. Plants poisonous to live stock in the Dominion are being investigated, and a watch maintained on all new plant species which come from overseas perchance they become noxious. Plant pollens occurring in peat swamps are studied in order to ascertain the past history and formation of swamp soils, and thereby secure guidance as to their utilisation for pasture or crops. The pollen content of the atmosphere is also under constant observation because of the influence of air-borne pollens on such allergic diseases as hay fever. Catchment Boards require botanical surveys and reports on the vegetation covering their districts, and here the ecologist is provided with an excellent opportunity. Likewise the taxonomist, who receives a wonderful range of plant species for identification and who has an extensive herbarium to assist in this all-important task of the botanist. Fibre plants such as linen flax, Phormium and Cordyline present interesting problems in plant physiology and call for microscopic page 8 studies of cellular arrangement in order to facilitate both understanding of quality and the processing methods best adopted for the extracting of fibre. The staff of the Botany Division is confronted with problems both applied and fundamental, which range through ecology, taxonomy, physiology and cytology. They require both field and laboratory study, and relate to many New Zealand problems of the utmost importance.

The Entomology Division, under the direction of Dr. D. Miller, is situated in Nelson, in the grounds of Cawthron Institute, with which it works in the fullest collaboration. A splendid entomological library, collections, insectaries, laboratories and equipment are available for every phase of insect study. As with all biological sciences, identification of species is of prime importance, and thousands of insects are received annually with requests for their names, characteristics, or methods of control. The insect collections and the library are available to assist in this work. The Division centres its activities on solving economic entomological problems of the Dominion, and these mostly are concerned with the control of noxious species. Biological control of such serious pests as woolly aphis of the apple, white butterfly and diamond-back moth, of brassicas, pear midge, and cottony cushion scale of citrus has been secured by importation of parasites. This success has only been secured after close study of both host and parasite under New Zealand conditions, and has called for both ingenuity and sound biological knowledge. Porina, an indigenous species of grass caterpillar, is a serious pest of pastures, particularly in the South Island, and has been brought under control by the use of poison bait applied with a manure spreader. A more serious pest of pastures, Odontria, the New Zealand grass grub, is presenting a much tougher problem and the staff of the Division still engaged on studies of its habits are testing the use of every known method of control, physical, chemical and biological, in order to check its ravages. This pest constitutes one of New Zealand's most serious problems, and the search for likely parasites is proceeding in Australia and South America.

The Agronomy Division is established at Lincoln, Canterbury, in the vicinity of Lincoln College. Mr. R. A. Calder is Director. This Division is concerned with the improvement of all farm crops grown under cultivation. It is responsible for providing, as a Pure Seed Station, the highest quality seed of each of the various farm crops grown in New Zealand. This work calls for the biologist who has a flair for plant selection, plant breeding and genetics. Each crop has first of all to be examined and careful selection made of individual plants possessed of desirable features. These plants will then be used for cross-fertilisation and their progenies again tested and selected until fixed. Then the final product has to be subjected to tests in all localities to ascertain how well it suits various parts of the Dominion. This gives in very brief outline the nature of the work required to be done on each crop. page 9 Up to the present the Division has brought about marked improvement in the quality and yield of such crops as oats, rape, kale, lupins, peas, carrots and lucerne. Vegetable crops are now being added to these field crops and programmes of selection, breeding, testing and multiplication of high quality strains are being pursued.

The Wheat Research Institute, under Dr. O. H. Frankel, has its area at Lincoln adjoining the Agronomy Division, and concentrates its efforts on selection, breeding and testing of wheat. Again the plant breeder and ecologist has to play the leading part. A statistically proved technique is adopted for the breeding and selection work required in wheat improvement and some 20 acres each year are devoted to the growing of thousands of plots of wheat. From this work thousands of rejects have to be made, but New Zealand has been provided with wheats suitable to her soil and climate, and providing easy harvesting for the farmer, good milling for the miller, ready baking for the baker, and an attractive loaf for the consumer. Cross T, Fife Tuscan, Taiaroa, Tainui, and Hilgendorf varieties have emerged from the hands of plant breeders at the Institute to change completely the wheat industry of the Dominion.

The Tobacco Research Station at Motueka, in charge of Mr. R. Thomson, is in the centre of the one tobacco growing district of New Zealand. While overseas varieties of tobacco are in the main relied upon, selections of these are made use of for breeding purposes which are designed to produce strains resistant to leaf mosaic and black root rot, both of which are regarded as viruses. Cultural trials involving manures, soil types, dates of planting and harvesting, establishment of seedlings, and a range of treatments of the plants at different stages of growth, are also in progress. Finally, the care and treatment of the leaf during its processing in the kilns and subsequent grading and bailing are followed through with investigations at each stage. Bearing in mind that quality of leaf is the all important factor in the tobacco crop, biological work covering genetics, breeding, ecology and plant physiology are called for in the investigations conducted on this crop.

Fruit Research is in progress at the Plant Diseases Division, Auckland, which has substations in Hawke's Bay and Central Otago. In Nelson the Appleby Research Orchard is used for manurial and spraying trials, while in Wellington provision is made for gas storage research. Fruit Research has an extensive range. It begins with studies of the soils on which orchards are established and finishes with fruit in raw, dried, or cooked form on the table. It embraces pip, stone, berry and citrus fruits. The soil and manurial work has a direct bearing on tree growth, fruit yield and fruit quality. New Zealand workers were first to discover that shortage of boron in the soil was responsible for the serious trouble, “corky core”, which rendered apples and pears unfit for marketing. The study of tree stocks and scions, propagation and page 10 pruning methods, fruit set, the influence of plant hormones upon trees and fruit production, all are matters which come within the scope of biology. The behaviour of the fruit under transport and storage conditions presents some fascinating study for the plant physiologist, while its protection against insect, fungus, bacterial and virus injuries is the concern of biologists of various interests. In the fruit industry there are many applied problems of immediate economic interest requiring attention. Many of these are such as provide an excellent opportunity for team work where biologists may work in association with chemists and physicists on projects having the full support and interest of the orchardists.

This gives in brief outline the scope and nature of the plant research work undertaken in various branches of the Department of Scientific and Industrial Research, and indicates the opportunities for those possessed of a bent for biological research to engage in work which has a distinct bearing on the future prosperity of New Zealand.