|dc.description.abstract||Field beans are a very old crop, known to man since the Bronze Age. Originally cultivated in the Middle East and the Mediterranean regions, they were used for both human consumption and animal feeding, and later, cultivation of the crop began in Europe and the United Kingdom. As a grain legume, field beans have a place in cropping rotations for two reasons. Firstly, they are regarded as a 'restorative crop' and grown to build soil fertility between successive cereal crops; and secondly, they provide a high protein grain, the amino acid balance of which is complementary to that of cereals so that if a diet consists of both grains, humans and non-ruminant animals receive a balance amino acid diet.
The thesis begins with a review of the history of the crop, current knowledge of its agronomic and climatic requirements (Chapter 1), and then an examination of the chemical composition of the grain, and its nutritive value as a food for both humans and stock is made (Chapter 2) The later papers (Chapters 3 to 11) discuss the agronomy of Vicia faba in Canterbury - a topic deliberately comprehensive so that the ramifications of any findings from research in Canterbury were able to be explored within the ambit of the study. Each of these chapters is written as a complete unit where the literature pertaining to the topic is briefly reviewed, methodology outlined and results presented and discussed in light of current knowledge. In the final chapter (Chapter 12), an overall discussion of field beans in Canterbury is presented.
Because of our historical and cultural links with the United Kingdom, many of our farming systems in New Zealand are based on, or derived from, agriculture in that area. Although they had been grown in Britain for centuries, agronomic research into the requirements of field beans began only at the end of the Second World War, and, as indicated in Chapter 1, is still not completely resolved. However, Vicia faba has potential in both human and animal diets (Chapter 2) and is worthy of further agronomic research so that maximum grain yields may be obtained.
A survey of farmers growing the crop commercially in Canterbury showed that knowledge of field bean agronomy cannot be transplanted directly from Europe and other field bean growing areas into Canterbury, and highlighted the importance of determining the agronomic requirements of the crop within the geographical area in which it is to be sown, as well as the need for disseminating this knowledge within the farming community.
Thus the first experiment undertaken in the 1976-77 season was designed to investigate at Lincoln College, the effects of time of sowing and plant population on growth and development (Chapter 4) and grain yield (Chapter 5) on Daffa, an 'autumn' cultivar, and Maris Bead, a 'spring' cultivar, of field beans. The second experiment in the following season (Chapter 6), was undertaken to provide more detailed information of the effect these two factors on yield of Maris Bead, and incorporated irrigation and pre-floral nitrogen treatments.
Climatic factors affecting grain yield of the cultivars were determined in Chapter 7. Continuation of the studies begun in Chapters 4 and 5 were made in Chapter 6 to shed some light as to the reasons why Maris Bead, the 'spring' cultivar should have out yielded Daffa in both autumn and spring sowings, and have produced its highest grain yield from autumn sowings.
When autumn, sown field bean plants often began to flower in late October, and, perhaps because there were few insect pollinators flying at this time, often failed to form flowers at early flowering nodes at the base of the reproductive zone. The effect of loss of basal flowers on grain yield, and the distribution of the grain yield over remaining reproductive nodes is presented in Chapter 9.
The effect of autumn sowing on nitrogen content of the grain is outlined in Chapter 10, and, as field beans are grown as a restorative crop in many rotations, an attempt is made in this chapter to determine the nitrogen yield of above-ground portions of the crop.
During the earlier experiments with the crop, it became apparent that many flowers were robbed by the short-tongued bumble bee. Chapter 11 examines the frequency of robbed flowers within autumn and spring sown field beans, the relationship between this process and floral structure, and attempts to determine the effect of robbing on subsequent development of the flower.
A detailed appraisal of field bean agronomy in Canterbury is given in the final chapter (Chapter 12).
Another relevant paper to which the author contributed may be found in the Appendix.||en