THE Wairarapa Age MORNING DAILY. WEDNESDAY, AUGUST 27, 1913. THE MENDELIAN THEORY.

Wairarapa Age, Volume XXV, Issue 10713, 27 August 1913, Page 4

THE Wairarapa Age MORNING DAILY. WEDNESDAY, AUGUST 27, 1913. THE MENDELIAN THEORY.

A very interesting paper, describing the progress that has been made in the Mendelian studies in Great Britain, was recently contributed by Professor Punnett, of the Cambridge University. The dramatic discovery of Mendel's work on plant-hybridisation in 1900 inaugurated a new era for the breeder of plants and animals, and the opportunities for advance in the knowledge of heredity were in no country more rapidly seized than in Great Britain. The seed here fell upon prepared soil, for the problems to which Mendel found » key had already begun, to engage the attention of Mr Bateson and of Miss Saunders in Cambridge. The account of the experiments which they had started in 1897 end published as the wellknown first report of the Evolution Committee to the Eoyal Society in 1902 was the most important contribution to the subject since Mendel's own paper, and was the firstt to open men's eyes to the vast possibilities latent in Mendel's work. A group of workers rapidly gathered round Bateson in Cambridge, and the contributions to be found under the names of Doncaster, Gregory, Lock, StaplesBrowne, Miss Durham, Miss Wheldale, and others bore witness to the activity of the rising school of genetics ijt.the University. All this work, like Mendel'd own, was designed and carried out purely with the desire to gain definite knowledge of the workings of heredity, and little or no results which might flow" from the application of this knowledge to,the affairs of those who bred annuals and planta for profit. The material for study was selected on tihe. ground of ifs cheapness, oi the ease with which it could be worked, and its suitability for giving a (speedy answer to the i problems put to it. Sweet-peas, mice, |. stocks, motlte, waapdrsgoins, s&i

poultry—such was the material investigated, and except for the lostnamed it oauld Hardly bo said to possess much eoonomio importance. But it bo happened that the stimulus to genetio work coincided with the rapid rise of the School of Agriculture in the University, and the enormous practical importance of the new knowledge was immediately appreciated by Professor Biffen, who was then starting his now-famous experimeataJs in the crossing of cereals. By making use of the methods of Mendelian analysis he was able to show that suoh qualities as strength, yield, and immunity to rust ware transmitted in accordanoe with Mendel's law of segregation, and consequently are under the oontrol of the investigator, who can now devise suitable experiments for combining them together at will. Improved wheats of this kind have already come into use in England, and, judging by the competition there is to secure the seed, they have already proved themselves a great success. The analysis of the wheat-plant is etill being actively carried on in Gambridge by Professor Biffen and his co-workers, and there is no doubt that as time goes on even better and more profitable varieties will be at the service of the British farmer. It is pleasant to be able to record that the importance of the work has been recognised by the Government, who have placed a considerable sum at the disposal of the .School of Agriculture j for research in plant-breeding. This j has rendered possible an increase in ike .scope of the work, and experiments are now being carried out on other plants-besides cerealß. -Among investigations now under way are some concerned with the tf ansmisjsion of fertility in fruit trees, whilethe striking success of Biff en's work' on the nature of immunity to rust in wheats has led to the search fox naturally immune individuals in other forms of plant-life. Experiments with potatoes have heen in progress for several years, arid, thanks to the energy of Dr Salaman, working on • his own estate near Cambridge, and of Mr Lesley, of the Sohool of Agriculture, the formation of a decent potato, naturally immune to PChytophthora infestans, seems within measurable distance of realisation. Nor are the researches at Cambridge confined to plants. Poultry was one of the first subjects of experiment by Bateson, and during the past ten years touch has been learned of the transmission of various characters. Offering as they do a number of features showing sex-link%d inheritance, poultry are of importance for gaining an insight into the nature of sex, and of studying the peculiar influenoe of each sex in the transmission of hereditary properties, Several of these sex-limited characters are now under investigation at Cambridge', while parallel are being carried on by Professor Bateson at Merton. Two other series of experiment likely to lead to knowledge of economic value are also being carried on at Cambridge. .The first of these is concerned with the inheritance of size, and consists in barefully following out the result of a cross between an ordinary fowl and a bantam. The work is not yet sufficiently advanced to permit of complete analysis, but the nature of the F2 generation raised last year strongly suggests that size depends upon definite factors which exihibit ordinary Mendelian segregation. ' The other set of experiments mentioned cbrioerns the inheritance of the brooding instinct in the hen and of the brown colour of the egg-shell. In England brown eggs are of greater value than white, but hitherto no breed laying brown eggs and in which the hens .never want to sit has yet been eitalnished. It may be that brown eggs are incompatible with the Eon-broody habit, just as it is sometimes stated that a breed of .cattle cannot be at the same time first-rate in both milk production and beef. It is hoped that the experiments in progress will eventually give definite evidence upon this point. .' Experiments have also been undertaken with sheep where the results of a dross between merino rams (from Australia) and Shropshire ewes are being carefully followed. The experiments have just reached the F2 generation, and it is hoped that the knowledge gained from them will eventually render it possible to combine the fleece of the merino with the good mutton qualities of other breeds. Besides the work just mentioned, there are other sets of experiments being carried out at Cambridge and Merton which may be regarded as forming a group by themselves. Bateson in 1905 was the first to describe in sweet-peas a remarkable case in which two characters oach exhibiting ordinary Mendelian segregations nevertheless showed a peculiar distribution with regard to one another. In this particular " instance the characters dealt with were colour, blue being dominant to red, and pollen-shape, long being dominant to round. Recent work, more especially that of Morgan in America, has shown that similar phenomena occur in animals, and there is no doubt that a proper understanding of tlrera will eventually turn out to be of much importance for the breeder of plants and animals. It is a matter of oommon observation that characters seem at time» to be transmitted in bunches, as it were, from one parent or other to the offspring, and it is likely that in such cases we are dealing with phenomena of the kind just outlined. The bestequipped institute in Great Britain for the study of genetics is undoubtedly the John Innes Horticultural Institution, at Merton, near Lomidistorted in 1909 with funds derived from private bequest, it was fortunate in securing Professor Bateson, who left Cambridge in 1910, as its first Director. Fortunately, also, its scope is broad, and the experimental work undertaken is concerned with the unravelling of the principles of inheritance in the widest sense, apart from considerations of direct economic return. Numbers of experiments are at present being carried out by Professor Bateson and his staff, principally with plants, not the least interesting, being a series of experiments dealing with fertility and sterility in fruit trees.