Page images
PDF
EPUB

REPORTS OF DEPARTMENTS.

ANALYTICAL CHEMISTRY.

Dr. E. M. Bailey in charge. 1. Control of Fertilizers. Eight hundred and eighty samples of commercial fertilizer have been analyzed, the results reported to the manufacturer and others interested, and the complete data classified and arranged for publication.

2. Inspection of Feeding Stuffs. Three hundred and fifty-two samples of commercial feeding stuffs and other fodder materials have been examined and the results published together with a discussion of the law relating to this subject. 3. Inspection of Foods and Drugs. Control and

Control and investigational work on food products and drugs has entailed the examination of about 1,800 samples.

4. Calibration of Babcock Glassware. Nearly 4,000 pieces of Babcock glassware have been checked for accuracy of calibration.

5. Inspection of Insecticides and Fungicides. About 70 samples of spraying and dusting materials were examined and the results published together with the text of the insecticide law recently enacted and rules and regulations for its enforcement as formulated jointly by the Director of this Station and the Dairy and Food commissioner.

6. Studies on Methods. Collaborative work has been carried on with the Association of Official Agricultural Chemists upon methods for the analysis of spices and other condiments and of cacao products.

7. Analysis of Diabetic Foods. The station has collaborated with the Council on Pharmacy and Chemistry of the American Medical Association on the subject of diabetic and special foods.

8. Analysis of Check Samples-Cottonseed Meal and Mixed Fertilizers. The Station has collaborated with the American Oil Chemists Society and the F. S. Royster Guano Co., in the analyses of check cottonseed meal and mixed fertilizers.

BIOCHEMISTRY.

Dr. T. B. Osborne in charge. (In collaboration with Dr. L. B. Mendel, Yale University.)

PROTEIN RESEARCH AND NUTRITION STUDIES. 1. A Study of the Proteins of Green Plants. Investigations of the constituents of the alfalfa plant have been continued. New methods of fractionation have been developed and have indicated the presence in alfalfa juice of new substances, including a new base, not yet identified. A protein with no carbohydrate impurity has been derived from cell cytoplasm of the spinach plant, by a new method of separation. Its isolation in a state of purity will be of importance in the study of the chemistry of the living cell.

2. The Relation of the Chemical Constitution of the Diet to the Development of Rickets. (With Dr. Park of the Yale School of Medicine.) Observations are being attempted under conditions of carefully controlled diet. Diets of purified food substances have been formulated which lead to the development of either rachitic or osteoporotic changes in the bones. It is inadvisable as yet to form generalizations from the extensive data collected.

3. Studies of the Relation of Vitamines to Nutrition. Experiments show that when smaller doses of protein-free vitamine B concentrate are fed to larger animals a decline in weight ensues; with intermediate doses there may be maintenance at various levels of body weight; with the larger vitamine B intake for the smaller animals growth ensues.

4. The Part Played by Proteins, Carbohydrates and Fats in Nutrition. (With cooperation of Drs. Park and Winternitz of the Yale School of Medicine.) The extent to which preformed carbohydrates are essential in metabolism, and the development of hypertrophy of the kidneys in protein-fed rats were further investigated. The success of varied types of experiments on diets extremely unlike those of every day experience seems to indicate that surprisingly large variations in the quantitative make-up of the diet may apparently be tolerated so long as the "law of minimum" is not violated.

5. The Effect on the Eye of a Deficiency of the Fat Soluble Vitamine. (With Dr. Judkin of the Yale School of Medicine.) It was found that ophthalmia occurs among rats living on “purified” Vitamine A free diets to a percentage as high as 82.

6. The Effect of Diet on Fertility. (With Dr. Mason of the Yale School of Medicine.) On our "standard" casein diet, which has proved adequate for growth but not for reproduction, definite degeneration of the germ cells of the testes of rats, reared from weaning on the casein diet, was recorded. Ordinary mixed diet has not restored sterile rats to a normal condition after periods of 100 days.

7. The Relation of the Chemical Structure of the Proteins to their Nutritive Value. Much remains to be learned concerning the part played in nutrition by the various amino-acids which proteins yield on digestion. As a preliminary to further study in this field much time has been devoted to preparing large quantities of pure amino-acids which can be used in feeding experiments.

BOTANY,

Dr. G. P. Clinton in charge. 1. The Effect of Fertilizers, Especially Nitrate of Soda, on the Growth, Yield, Longevity and "Yellows" of Peaches. Since it was started in 1909, records in this experiment have been kept on the health and length of life of each tree, of the growth in diameter of the trunk during the earlier years and of the yield from each during the bearing years. Since 1916 nitrate of soda has been the fertilization used on each of the nine different blocks.

Serious drought in July 1924, and later, a severe hail storm, practically ruined the season's crop. The chief causes of failures and poor crops have been winter and drought injuries, fungi and insects being secondary in importance.

2. The Nature and Cause of Mosaic Disease of Plants. The cause of mosaic disease still remains in doubt, altho interesting observations have been made, some of them apparently new. The experiment represents a continuation of work on Calico of Tobacco published several years ago, and is chiefly concerned with that host and the relationship of its mosaic to other hosts. The work of the past two years has been chiefly microscopic and with varied infectional experiments outdoors and in the greenhouse.

3. The Ustilaginales of North America. This is a supplement to the work the writer published some years ago. During the winter material was partially assembled but not completed. The work may be finished for publication during the coming year.

4. The Rusts of Connecticut. This is a list of the rusts, with their hosts, so far collected in this state. Their distribution is given by towns, together with the dates of collection, collectors, and occasional notes. Every town in the state is represented by one or more collections. Total collections now number more than 2,500, representing nearly 120 species and 20 genera. The manuscript for publication, including keys to the genera and species, has been partially prepared.

5. Plant Disease Survey of Connecticut. Altho a dry season was experienced, on the whole rather unfavorable for fungous diseases, the Disease Survey for 1924 includes more than the usual number of notes on distribution, etc. Two or three new bacterial diseases of economic plants were listed for the first time. Preliminary reports to the U. S. Bureau of Plant Industry have been made.

6. Thielavia Basicola, & Study of the Perfect Stage. Evidence has accumulated that the conidium-chlamydospore strains and the perithecial strains do not belong to the same fungus, altho the perithecia have been hitherto considered the perfect stage of Thielavia basicola. Successful crossings besides those

of Thielavia basicola and Thielaviopsis basicola have been made of asco strains with a species of Aspergillus and Fusicladium pyrinum as well as with Cladosporium fulvum. Crossings made with Thielaviopsis paradoxa failed to produced perithecia. Attempts to determine the parasitism of the asco strains have so far yielded negative results altho perithecia have been found deeply embedded in the roots of tobacco, pea and violet, but in these cases always associated with the conidium-chlamydospore stages.

7. A Study of Pythiums. Artificial cultures of various fungi are obtained and kept going on special media in the test tubes. These are then available for special study as desired. Pythium species obtained from about a dozen different hosts, chiefly as dampening-off fungi, are among those now being especially collected.

8. Comparison of Spraying and Dusting on Apples and Peaches, Especially to Try New Dusts. (Joint project with Entomological Department.) For fungi, spraying has uniformly given the better control. This year, however, the dust control more nearly approached the spraying because of dry weather which prevented the development of fungi. A test of spray and dust combination did not give marked results but it seems desirable to experiment further with combinations of spray and dust as this seems to be the way that dust may be used in the control of apple troubles.

9. Control of Celery Blights with Sprays and Dusts. During the past year tests were made in thirteen fields with eight different growers. Home-made 4-4-50 Bordeaux mixture was compared with Niagara Sulfodust and Niagara D25 Copper Dust, checks being kept in each test. Comparatively little blight injury occurred in the fields so that decisive results were not obtained. On the whole control and yields seem to point to the following order of the plots: (1) Bordeaux Mixture, (2) Copper Dust, (3) Sulphur Dust, (4) Check.

10. Control of Root Rot and Improvement of Sweet Corn by Seed Selection. This experiment was started in 1920 to determine if it was possible, by seed selection, to control root and ear rots of sweet corn grown for seed. A composite sample of seed selected from the best lines during the preceding four years was planted in comparison with unselected seed of the same strain and unselected seed of the same variety grown in the same locality from a different seed source. The selected seed gave a better stand and more even growth especially early in the season. The number of diseased ears did not differ greatly in the three plots, but the yields of selected seed were much greater. The selected seed has also shown a steady increase in average per cent of diseasefree ears, determined by germination tests.

11. Comparison of Sprays and Dusts on Potatoes. (Joint project with Entomology Department.) Copper dust has been compared with 4-4-50 Bordeaux mixture in this experiment. There has been no blight in three years but each year the sprayed plot has given greater yield than the dusted, and the dusted has been better than the check. The sprayed vines have shown less injury from tipburn and flea beetle injury and have lived longer than those in the dusted and check plots.

12. Seed Testing. This is one of the oldest lines of work of the Station and is largely routine in nature. Farmers, and others, wishing to know the germination and purity of seeds purchased, send them in for testing. Particular attention is paid to testing seed-corn for experimental purposes. At times special work is done on certain seeds. For example, grass and forage crop seeds were tested the past year to determine if their standard of purity and germination in this state compared favorably with that in other states, which seems to be the case as shown by the result of the tests.

13. Peach "Yellows." Started in connection with fertilizer experiments of peaches in 1908, this study has consisted, in part, of "Yellows” surveys in different orchards over a series of years. Budding and other infection experiments have also been carried on. No results have been published except general notes.

14. Musk Melons and Blight Resistance. Some time ago this experiment was carried on over a period of several years. It consisted in growing 100 so-called varieties for three years and in making studies on blight resistance, quality and yield with sprayed and unsprayed vines of a selected variety, Miller's Cream. The results have never been published and no recent work has been done; the fields of commercial growers have been visited from time to time.

15. Chestnut Blight. This subject was investigated and the results published some years ago. Renewed interest in the future of the chestnut in this state has induced the Botany and Forestry departments to take up some new phases of the subject in 1924. Surveys were made in several marked localities on the number of dead, diseased and free sprouts, seedlings and trees. Records will be kept and these plots examined again yearly. Seed was obtained and placed outdoors to grow seedlings, in part, for planting eventually under forest conditions, and, in part, for inoculation with old and new cultures of the blight.

16. White Pine Blister Rust. Two papers have already been published on this subject. Only a little infection work has been done during the past year. Considerable data has been obtained that has not been published. A final study may be made of assembled data during 1925 and the results published in the next report.

17. Infection Experiments and Other Studies with Rusts. Work along infection lines has been carried on in the past. Much of

« PreviousContinue »