The mycological investigation appeared to show that the only constant organism found in the living roots of unhealthy plants is an endotrophic mycorrhiza of the type bearing arbuscules and vesicles, and that this organism invades chiefly the fine absorbing roots. The maximum infestation occurs about flowering time when fine fibrous roots are produced in great abundance, with the result that the roots are ruptured and drop off. These root fragments infect the surrounding soil and young runners become infected when they strike root in the soil. ANIMAL DISEASES RESEARCH ASSOCIATION OF SCOTLAND. Research Staff.--Mr A. Brownlee was appointed Junior Research Assistant in January and Mr D. R. Wilson Second Junior Research Assistant in June. Buildings. The Institute at Moredun was officially opened by the Secretary of State for Scotland on 4th November. Motor Field Laboratory.—In last year's Report reference was made to the Motor Field Laboratory presented by Mr Falconer L. Wallace. The equipment of this laboratory was completed during the year. Braxy. The production of the preventive vaccine has now reached such proportions as, with the existing staff, to be a real embarrassment to research work. Fully 37,000 hoggs were inoculated in the autumn of 1926, and the death-rate during 1926-27 in inoculated hoggs for which returns were received was 1.35 per cent. as against 6·35 per cent. in controls. Vaccine sufficient to inoculate 48,000 hoggs was issued in the autumn of 1927. There is still need for investigation into means of preparing a vaccine capable of conferring greater immunity without increasing the risks involved. Further research also appears to be necessary to ascertain to what extent different types of the so-called braxy bacillus exist, and whether allied types of micro-organisms cause similar types of disease in sheep. Lamb Dysentery.-Experiments were carried out with the small flock of ewes and one tup, the acquisition of which was reported last year, but no evidence of ante-natal infection could be found. Further experiments with newborn lambs demonstrated that infection takes place after birth through the mouth. Bacteriological work with a view to isolating the causal agent is still in progress. Considerable success was achieved in immunising lambs by inoculation with a serum. "Grass Disease" in Horses.-The scope of this enquiry has been very much widened. Investigators who specialise in many branches of science have been approached and are helping in the study of the subject. At the same time the work in progress has resulted in the gradual elimination of various theories regarding the cause of the disease. The work is to a certain extent hampered by the lack of present knowledge regarding the physiology of the larger farm animals. 66 Scrapie."-Research into the transmission of Scrapie has begun. Calmette and Guerin's Anti Tuberculosis Vaccine. The experiments mentioned in previous Reports were continued, but it will not be possible for another two or three years to estimate the value of the vaccine. Miscellaneous.-A great deal of routine work was done with regard to the diagnosis of specimens sent for examination, the preparation of vaccines, and the investigation of unusual outbreaks of disease. SCOTTISH SOCIETY FOR RESEARCH IN PLANT BREEDING. PLANT-BREEDING STATION. The work of the Society during the year comprised research in the breeding of oats, potatoes, herbage plants, and swedes. Oats.-Attention was directed mainly to obtaining crosses from early-ripening and from stiff-strawed varieties. About 300 selections of unfixed strains of oats ranging from the first to the sixth generation were sown for further comparison and selection. Small samples of all the promising hybrids that were breeding true to type in 1926 were sent to the Plant Registration Station for trial in 1927. A hybrid oat of the Sandy type was sent for trial in several areas in Aberdeenshire and Kincardineshire for comparison there with the Sandy oat. The provisional reports received indicated that in most of the trials this variety had grown satisfactorily, and that its strength of straw and its period of ripening had compared favourably with the control varieties. Potatoes.-At Ainville the results of the previous year's work had indicated the desirability of breeding from healthy parent plants if possible. Healthy tubers of over 20 named varieties from Craibstone Experimental Farm, Aberdeen, were used. Many cross pollinations and selfings were made and a considerable number of berries were obtained. In continuation of the experiments on selfing, certain F1 and F2 generation plants from selfed seed were again successfully selfed. About 1,100 seedlings were raised from crossed seed and selfed seed, and observations were made periodically to note whether symptoms of leaf-roll or mosaic appeared in any seedling during the season. As before, symptoms of virus disease developed in a small proportion of the seedlings and these seedlings were immediately isolated. Of the seedlings raised in 1926, over 700 were grown in 1927 for further observation and selection. There were sent to the Board's Seed-Testing Station 765 single-tuber selections for inclusion in the Wart Disease Trials. At East Craigs, duplicate samples each consisting of six tubers of all the 350 selected seedlings raised at Ainville in 1926, were grown for observation and comparison with certain standard varieties as regards yield of tubers and relative vigour. Particular attention was paid to the occurrence of symptoms of virus disease in any of the seedlings. Plants of the same variety propagated vegetatively both at East Craigs and Ainville were compared, and the results obtained so far indicate that the plants from seedlings raised at Ainville are much healthier than those of the same age raised at East Craigs. Herbage.-Wild populations have been further studied from the genetical standpoint. The preliminary account of these investigations has been published in the Journal of Genetics. The collection of living material from different habitats has been continued, and this material is being studied in an environment which has been made as uniform as possible. During 1927 the breeding work was concentrated on the two species Phleum pratense and P. alpinum. Besides the crossing of similar phenotypes within wild populations of P. pratense, a cross between P. pratense and P. alpinum has been studied in detail. A pasture strain of Lolium perenne is in the preliminary stages of seed multiplication, and, in addition, a few pasture strains of Phleum pratense are being vegetatively multiplied preparatory to the initial seeding. Swedes.-About 170 plants were selfed in pollen-proof bags in continuation of the investigation into the effects of inbreeding in swedes. Seed was obtained for large plot trials by seeding, under natural isolation, about 25 bulbs each of three chosen lines. Hand crossings, numbering about 50, were made for future experiments concerning the inheritance of certain characters in swedes and turnips. About 70 strains of seed obtained from selfed plants were sown in plots in replicate with parent commercial varieties for comparison. Most of these were in the third generation of selffertilisation. Notes on the morphological characters were made throughout the growing season, and additional information regarding inheritance of "bolting" and "splitting was obtained. Selections were made for seeding in 1928. Tests of resistance to "finger-and-toe" disease have been continued. A small yield trial was laid out consisting of three promising lines and a control. Determination of dry-matter content, sugar content, and yield were made upon the replicated plots. Selections on the basis of dry-matter content in individual bulbs were made on a number of lines. Some botanical selections were made from commercial plots. Arrangements were made by the Society and the Chemistry Department of the Edinburgh and East of Scotland College of Agriculture to co-operate in a joint investigation to determine the value, as a method of selecting parent roots of high feeding value, of the "soluble solids" test recommended by the Chemical Sub-Committee of the Research Committee of the Board of Agriculture for Scotland. All the swedes analysed were grown at the Station, and all the selections subsequently to be made from them will be seeded there. DAIRY RESEARCH. Further progress was made in connection with the establishment of a Dairy Research Institute in the south-west of Scotland. A Joint Committee of Management was appointed by the Secretary of State, as follows : Principal Sir Donald MacAlister, Bart., Representing the Professor Robert Muir, F.R.S., M.D., LL.D. Thomas C. Lindsay, Esq. John Speir, Esq. Principal W. G. R. Paterson, B.Sc., N.D.A. Lord Weir. Mrs Houison Crauford. University of Representing the Sir Donald MacAlister was appointed first Chairman of the Committee. Dr. H. H. Green, Professor of Biochemistry and Bacteriology in the Veterinary Faculty of Pretoria University and SubDirector of the Research Institute at Ouderste Poort, has been offered the post of Director of the new Institute, but had not entered on his duties at the end of the year. Negotiations are in progress with a view to the establishment of the Institute at Auchincruive, on the estate offered by Mr J. M. Hannah of Girvan Mains to the Secretary of State for Scotland for the purposes of agricultural education and research in the West of Scotland, reference to which was made in the Board's last Report. Mr Hannah has generously offered additional land at Auchincruive to enable the Dairy Research Institute and the Dairy School of the West of Scotland Agricultural College to be set up in close proximity to each other in accordance with the terms of his offer. VARIATION IN THE COMPOSITION OF Cows' MILK. Following on a conference called by the Ministry of Agriculture and Fisheries to discuss questions relating to the extent and causes of variation in the composition of cows' milk, a small executive committee was set up representative of the Agricultural Departments for England, Scotland, and Northern Ireland to take charge of the various schemes of investigation proposed at the conference. The committee was given power to set up scientific subcommittees to deal with different aspects of the work proposed, and appointed sub-committees, which include Scottish representatives, for the following purposes :-(1) to make a statistical analysis of existing data relating to variations in the composition of cows' milk; (2) to examine the facilities for investigating various subjects relating to variation in milk composition, and to prepare a scheme of work together with estimates of costs. SCHEME OF GRADED SALARIES FOR RESEARCH WORKERS. It was stated in the Board's last Report that the Treasury and the Development Commissioners had accepted the principle of the adoption for workers in the Scottish Agricultural Research Institutions of the system of graded salaries already in operation in England. The scheme was applied, with effect as from 1st April 1927, to certain members of the staffs of the following Institutions :Rowett Research Institute; Animal Breeding Research Department, Edinburgh University; Animal Diseases Research Association Scottish Society for Research in Plant Breeding. RESEARCH SCHOLARSHIPS IN AGRICULTURAL SCIENCE. The one Scottish student holding a scholarship awarded in 1925 relinquished his scholarship during the year. One of the two students to whom scholarships were awarded in 1926 was unable to take up the scholarship, while to the other an additional allowance was awarded to enable him to spend six months abroad in the laboratories of Professor Mitcherlich at Konigsberg and Professor Neubauer at Dresden. Four new scholarships were awarded to Scottish students during the year, two being of the value of £200 per annum tenable for three years, one of £200 per annum for one year, and one of £200 per annum, less the value of a scholarship already held by the student, tenable for three years. Two of the scholarships are tenable during the first year at the School of Agriculture, Cambridge, one at the Imperial College of Science and Technology, and one at the Animal Breeding Research Department, Edinburgh University. TRAVELLING RESEARCH FELLOWSHIPS AND GRANTS FOR THE REPRESENTATION OF AGRICULTURAL SCIENCE AT INTERNATIONAL CONFERENCES. On the recommendation of the Advisory Committee on Agricultural Science, awards were made under this scheme to the following persons for the purposes indicated: (1) Professor J. Hendrick, North of Scotland College of Agriculture-to attend the First International Con gress of Soil Science at Washington in June and July 1927. (2) Dr. W. G. Ogg, Edinburgh and East of Scotland College of Agriculture-to attend the same Congress. (3) Dr. F. A. E. Crew, Animal Breeding Research Department, Edinburgh University-to attend the Fifth International Genetical Conference at Berlin, and to visit Hanover in September 1927. (4) Mr A. Cunningham, Edinburgh and East of Scotland College of Agriculture-to study methods of investigation of Bacterial Activity in Soils, and to visit Agricultural Experimental Stations in Germany during a period of about one month in the summer of 1927. |