PLANT SELECTION AND BREEDING.

New Zealand Journal of Agriculture, Volume I, Issue 4, 15 September 1910, Page 296

PLANT SELECTION AND BREEDING.

Variations in Wheat : Ruakura.

The following account showing the numerous varieties obtained from a small sample of wheat is interesting :• — In May, 1909, a small packet of wheat named “ Fultz ” was obtained from the United States of America. The wheat was sown in a box in the greenhouse on 4th June, 1909. The; plants, 132 in number, were above ground on 12th June, the germination being 95 per cent. These werehardened off under a canvas cover, and transplanted on 23rd July, care being taken to set each plant separately. ‘ They made rapid growth during, the months of September and October, and did not receive any check by the frost. During November and the early part of December they were badly affected by rust.- Grain began to form during the first week in December, and on Bth December the plot was covered with scrim as a protection against birds. Prior to this, 27 of the plants were culled. There was great variation in the vigour' of the different plants, and also in the heads, many being bearded while others were not,' thus showing signs of being a mixture, and not a culture of ' a single type. The ripening was also very irregular, the bearded varieties ripening earlier than the beardless.! The time of ripening was from 20th i December, 1909, to 7th January, 1910.

From the 105 plants 60 more were culled, being badly rusted or of very poor type. The remaining plants have been divided into the following types ; . the number of plants of each distinct type is also given :■ —

' . Number ... ' of Plants, (a.) Long white awnless heads of first quality .. .. 18 ' (b.) Short white awnless heads of first quality . .. .. 2 (c.) Short brown awnless heads of first quality ... ..1 (d.) Long brown bearded heads, hairy .... .. 1 (e.) Long brown awnless heads, hairy ... .. .. 1 (/.) Long brown bearded heads, glabrous .. ... .. 1 (g.) Short white bearded heads, glabrous .. .. ..10 (A.) Short white half-bearded heads .. .. .. 3.

Of the 18 plants of the dominant variety, six exceptionally good ones were selected, with the intention of sowing seed from these plants in separate plots next season. One plant yielded 71 heads, with an average of 30 grains in each, and another yielded 56 heads, with an average of 46 grains in •each. The types (a), (e), and (g) are the only ones worth cultivating ; but a continuation of the trial is necessary before finally discarding any of the varieties. _■ / Selection of Varieties, Oats : Ruakura. Mr. A. W. Green; Horticulturist, reports : It' has been proved in the last season beyond doubt, through the many varied and individual cultivations under observation, that little can be gained towards improvement in the yield of grain until something more has been accomplished .towards the selection of rust-proof varieties. The principal selections, therefore, were along the line of resistance to disease, .and some excellent results have been obtained. The seed of all plants chosen from the main crops last year was sown .separately in rows of equal length, and the yield of each harvested separately. Specimens that were attacked by rust, either on the leaves or on the stalks, were discarded,,.;. only .those being preserved which were free from disease. For example, in one variety, of which fifty selections were sown,' all except six were discarded.'?? These ripened without showing any signs of disease •during the whole period of growth. In order to give tests as to their resistant qualities, plants from neighbouring fields,, .badly affected with rust, were brought into actual contact with the cultivations. Another lot badly affected with smut was also introduced. These . proved of valuable assistance in the culling-out of the initial selections. It was by this method that the varieties Tartar King,' Rival, and Colossal proved susceptible to .rust, and these had been chosen for breeding on the lines of yield-increase. Varieties from which selections have given the best results are Algerian, Argentina, Red Rust-proof, and Garton’s Regenerated.

Phormium tenax.

Experiments in connection with the improvement of Phormium tenax by the raising of large numbers of seedlings, obtained from selected varieties, are progressing favourably. Mr. Green reports : Already many hybrids and chance seedlings have been singled out,, which .show a marked increase in the percentage of fibre yielded over the average type of plant. These are to be planted out under numbers, and grown to the flowering-stage. The leaves then become fully developed, and their

characteristics can be better studied. The plot planted during 1908, with a single specimen of each variety collected, is shortly expected to afford a wide field for research work. . Out of the fifty-five isolated types, only . two specimens flowered — Phormium Cookianum and Phormium Putaiore.

The large area which is planted with several varieties has reached the stage for cutting, and most of the plants bore seed this season. This area contains several . types, apparently intermediates between Phormium Cookianum and Phormium tenax, and it was noticed that these came into flower, set seed, and even ripened during these periods recorded for Phormium Cookianum and tenax (Putaiore).

-Certainly these two specimens which flowered in the test plot may not represent the extremes of variation which might exist in Phormium, but it seems to point to the fact that Phormium is but two distinct species, and the other so-called varieties are but intermediates which have originated by cross-pollination. ' .

Several pounds of seed. have been collected during the latter end of March. This is intended for immediate sowing.

Unit Plant Selection,

The officer lately in charge of the . plant-breeding work reports as follows :—• .

. Plant-breeding at Moumahaki in this second season of the work has been carried out on much the same lines as in the previous year, although on a more extensive scale. In the' first year several hundred especially distinct individual pUnts were chosen from among the numerous wheat, oat, and barley varieties growing on this experimental farm. The best head or ear of grain was harvested from each separately, and all grown on, side by side, this summer, to allow of a more complete study of their apparent superior qualities as noted when each mother plant was discovered. This system, called “ unit plant selection,” is the one used with , marked success by Dr. Nillson and his staff, at the Svalof Plant-breeding. Station, in Sweden. It is based upon the now ■ generally accepted' theory that most of our old agricultural-plant varieties, particularly cereals and grasses, are in reality composed of several and often numerous quite distinct unit species or types, each invariably reproducing its progeny perfectly “ true.” How all these types came into existence, whether by mutation, by accidental cross-fertilization, or by gradual evolution, is still largely a matter of keen controversy among scientific men ; but for use in practical plant-breeding work, the simple fact that all these “ forms ” of much-varying agricultural value do exist, and that they will in most instances come quite “ true ” from seed, is the only essential knowledge required.

For this method of plant-breeding, therefore, the main indispensable faculty is that of scrupulously careful observationto be able to go through a cereal crop and pick out any individual differences among the plants in length and stiffness of straw, size of ear and spikelet, resistance to rust, and other diseases, &c. Once these distinct unit species have been isolated, it only remains to sow their seed under uniform conditions the following season, and if any prove superior to ihe varieties from which: they were selected, and providing they are quite fixed in character, to again harvest only the best plants, and go on increasing the stock of seed until enough has been secured for general distribution.

When it is remembered that the progeny of one single oat-head can in four years increase to 500 bushels or more, it-will be seen that this system of working is not by any means a slow process. All the selections made on this station last year have been grown this summer under, as near ordinary field conditions as possible, and their minutest differentiating characteristics carefully noted from early growth until full maturity.

Every type showing the slightest possibility of being an improvement on its mother variety has been rigidly reselected and harvested ready for further testing on a larger scale next season.

OAT-SELECTIONS.

Algerians.

It is generally agreed that if oat-growing is ever to extend much in the North Island, an improved rust-resistant variety is absolutely essential. . The Algerian is undoubtedly a reliable rust-resister, with a highly nutritive straw, and is also a fairly good cropper ; but the grain is comparatively poor in quality, having a thick coarse husk and a small kernel. Therefore during this and the previous summer most attention has been concentrated upon, the object of improving the grain of the Algerian oat, and also the rust-resisting ability of the otherwise superior white-grain varieties. All the crops of Algerian and numerous other sorts have been exhaustively searched for improved types of plants, and, although this year’s tests have brought nothing startling to light so far, there is every reason to believe that at least three of the 117 Algerian selections made in 1908-9 will eventually prove to have advantages over the common Algerian. In two cases the rust-resisting and cropping ability are nothing exceptional (for that variety), but the grain of these two newly discovered types shows marked improvement in quality and general appearance as compared with the usual rough, wild-looking grain. One type in particular, at present indexed as number 0886, has a mediumsized grain, plump in proportion, and is of a pale-dun colour, while the long awn, so prominent on common Algerians, is here almost absent. In' this instance the original mother-plant was selected for its specially dark-green appearance as seen when growing in the field, no other exceptional characteristic being noticeable thenthus showing that quite unseen qualities may go hand in hand with the slightest deviation in outward appearance as compared with the surrounding plants. Another selection, at present called 08129, is similar in all respects to the usual Algerian, except that the grain has not such a coarse husk and is almost pure white in colour.

Selection 0883 is also much like an ordinary Algerian, but that it shows decided promise of being a heavier yielder and an extra good rust-resister — not even the leaves on any plant showing a vestige of the disease right through this summer. As stated in 1909 report, the oat crops here were remarkably free from rust-attacks during the 1908-9 season, some of the white-grain varieties, such as Garton, Sparrowbill, Danish, and Waverley, maturing with very little damage. This naturally led to many selections being made from them, which, although showing indications, were not actually resistant, and in the ordinary rust-prevalent . season they would not have .escaped. However, this summer, rust \Puccinid~~grdminis F. avence)" has ’ been ex-

tremely severe on all oats, and quite a number of the selections, even among those from Algerians, have succumbed. Several of which I had great hopes were completely annihilated, while some otherwise really good types were so damaged as to prove their further propagation useless. On the whole this aggravated attack of rust has been good for the work, as it has made a clean- sweep of many selections and several so-called resistant varieties which otherwise might have led on a false scent. At the same time it is much to be regretted that a number of selections, taken from ordinary white oats, which showed really good promise in every direction except rust-resistance, and which for less rust-infected localities might have been decided improvements, were entirely lost. Among the Algerian selections one rather unique discovery made is that there are at least three distinct types of that variety just as liable to succumb as many of the white-grain oats. A few grains have, with difficulty, been saved from one of these, in order to make further investigation, it being universally understood that rust can do very little damage to any Algerian, plants. ■' Another matter worth noting is that among the progeny of all the selections not one single departure could be found from the botanical characteristics as noted down when each original mother-plant was chosen, thus entirely supporting the theory propounded by Hugo de Vries, Dr. Nillson, Professor Bailey, and 1 others.

Russian White Rust-proof Oats.

In 1908 a small block of this variety was grown along with the other sorts, and, although oats were not badly rusted in that year, the Russian White on the whole was. the most injured of any, leading to the conclusion that some other “ form ” of rust (Puccinia) is prevalent among oats in its country of origin ; but this summer, strangely enough, several of the selections taken from that variety in 1908-9 have much resisted the disease —quite as well, in fact, as some of the best Algerian types. These Russian White selections were ah made for extra stiff straw, large heads, and freeness from rust, and, from present indications, several of them are likely to prove valuable. They appear to be heavy yielders, but have a rather small grain. • .

Other Varieties.

The 1908-9 selections made from the following varieties were all entirely destroyed by rust: Tartar King, Goldfinder, New Abundance, Bountiful, Rival, S.orm King, Garton, Waverley, Sparrowbill, Excelsior, Danish, Universal.

A small block each of the following additional varieties was tested this year, but, /owing mainly to the remarkably severe rust-attack, hardly a mature grain was produced, even by Argentina and Red Rust-proof : Colossal, Early Champion, Big Four, Argentina, ' Rosebery, Red Rust-proof, Silvermine, Great Dakota, Swedish Select, Ligowo, Triumph, Newmarket, Dun, Webb’s Prolific, Yield er.

No more penetrating attack of rust than the one experienced during the past summer could ever be expected, and therefore it can be taken for granted that the oat-selections which have pulled through possess constitution to resist infection in a very marked degree. During the 1909-10 season the Algerian oat crops were again systematically searched for any further as yet untested types, and as a result the grain

from the best head each of some fifteen likely-looking plants has also been put aside for isolation on the breeding-plots next spring.

OAT-MILDEW.

• An early sown Algerian crop was badly attacked by oat-mildew (Erysiphe graminis}, which first formed small patches and then gradually spread over large portions of the field, the plants towards the centre of each patch becoming very stunted, and rarely reaching more than 2 ft. in height. Several individual plants were discovered growing in the midst of the infected areas which did not appear mildewed in the least. Whether these rare exceptions accidentally missed attack, or whether they have constitutions to resist the disease, it is impossible to say yet. The grain from the best head on each plant was harvested separately, andjjwill be grown on with the other 1909 selections.

OAT CROSS-BREEDING.

Some forty-three cross-fertilizations between various 1908 Algerian types, and also between these and several 1908 Russian White types, were undertaken, but, owing partly to the inclement weather during Christmas week, only thirteen of these proved anyway successful.

The progeny of the crosses will be closely watched, and if any improved qualities appear, systematic selection will be carried out for the purpose of fixing their characters.

WHEAT-SELECTIONS.

The wheat-plant breeding experiments have been conducted on similar lines to those with oats; some fifty-one selections made from the varieties grown here in 1908-9 having been planted this spring, and their good or bad qualities carefully noted through every stage of their development. With a few exceptions, all the selections have proved quite distinct forms or typesnearly every one showing some decided departure from the predominant type of the variety undergoing selection. ■ - ■ ' < The most promising selections are those taken from Federation and this farm’s main-crop variety, Marshall’s White Chaff. One of the former, at present indexed as number 0812, has all the stiff straw and grain-holding qualities of that remarkable variety, with the additional advantage of an extra-long compact ear, averaging twenty-three spikelets per ear, as compared with barely twenty on the best other types of the same variety. Another Federation, type (0814) has a very stiff and exceptionally short straw, almost uniformly 31 in. in length, and also an ear well above the average size.

Of the twenty-three Marshall’s White Chaff selections, five show very good qualities, one in particular (0844) having a stiffer straw than is usual with that variety, and in addition a remarkably compact ear which ought to hold its grain well. ■ . Another type (0848) shows promise of being an extra heavy yielder. The Tuscan Solid Straw selections have produced what appears to be rather a prolific type (0838), with very long ears and an especially finequality grain. It is also about a fortnight, earlier in ripening, and has the ■characteristic solid straw.

The results from the larger and more practical tests of these and numerous ■other promising wheat-selections will be anxiously watched for. • ■■

Except in one particular case, all the wheat-selections made in 1908-9 have come quite uniformly “ true ” to the descriptions as noted down when each original mother-plant was chosen. That single exception (0841), although only one ear was harvested, has split up this summer into no less than three quite distinct forms, hardly 25 per cent, of this year’s plants being identical with the one originally selected. Whether these are genuine mutations or the result of some recent accidental cross-fertilization it is impossible to say yet, but there are quite a number of similar and apparently fixed forms growing among the main crop of Marshall’s White Chaff —this being the same “ stock ” from which selection 0841 was extracted. Although none of these appear so good as the selection from which they sprang, yet their manner of appearance is so interesting that it is intended 'to grow them all separately, and keep a close watch for any further developments.

Owing to the heavy blizzard experienced here during Christmas week, and to the large amount of rain which has fallen since’ then, all wheats have done very poorly as compared with the previous season. A disease (probably Cladosporium herbarum) which caused the ears to become blackened and shrivelled to a marked degree did considerable damage, but those varieties and types having extra-compact ears. appeared to resist this disease the best. / '

Rust (Puccinia graminis F. tritici) was more or less in evidence among all the wheats, but did not do anything like so much harm as the first-men-tioned disease. -

Other Varieties.

■ A small block each of the following additional varieties was tested this year : , Syndicate, Australian Tuscan, Bunyip, Firbank, Webb’s Challenge, John Brown, White Essex, Comeback (special stock), Plover, Zealand, Laghmor Solid Straw , Tuscan, Squarehead, Bobs, New Era, Red King, Bordsley, Red Chaff, Masters’s Treasure, Masters’s Red Marvel, Masters’s White Marvel, Masters’s Sensation ; also Red Emmer, White Spelt, Red Spelt. .

Of these, New Era, John Brown,, and Bobs were the most successful, but none came anywhere near so good as the Federation and Marshall’s White Chaff selections. -

1 ’ Masters’s new varieties —-Treasure, Red Marvel, White Marvel, and Sensation — very poorly indeed, producing small badly filled ears. New Era is one of Garton’s breeding, and, except for a rather long weak straw, appears to be very. good. In, appearance it is similar to Tall Neapolitan. The ears are much bearded, and often 8 in. in length, while the grain is darkred in colour and very large. This variety will be grown more extensively next year, as will also two especially good selections made from it.

During the 1909-10 season the wheat crops on this experiment-station were again gone over for any more new types. The best ear each from some twenty-nine extra fine-looking plants was selected, mostly from the main crop of Federation, and will all be grown separately next summer.

WHEAT CROSS-BREEDING.

Thirty-two cross-fertilizations were made among the various fixed types of wheats; mostly between those taken from Federation and Marshall’s White. Chaff. Of these, seventeen have proved successful... Their progeny will be handled in the same manner as the. oat crosses.

A small sample of one of the recently discovered wild, wheats (Triticum vulgare dicoccoides) sent to the . Department by Professor M. ‘ Kuernicke, of the Royal Agricultural Academy, Bonn, Germany, will be grown here next spring, and probably used , for crossing with the best cultivated varieties. In its present condition it is said to be of little value for agricultural purposes, but it may have certain ‘qualities which are superior. -

MALTING-BARLEY SELECTIONS.

Of the eleven malting-barley selections made in 1908-9 not one has proved anything above the ordinary, and therefore all of them have been abandoned.

Sixteen fresh selections were taken from this year’s crops, and will be tested in a similar way. ■ •

All the malting-barley varieties.grown here yet have proved very uniform in character, making it extremely difficult to find plants worth harvesting separately. ■ ' CAPE (OR feed) BARLEY SELECTIONS.

Several of 'these taken from the 19084) crops show every appearanceof being, decided improvements upon the common stock., The apparent difference in cropping is so marked that many farmers casually walking through, the. breeding have, been struck with the contrast. I. had long ago noticed .that Cape.-., barley crops usually contain a. proportion of extra-large ears ; but,' not having examined them, very closely,. I concluded that these were produced by the usual small-eared plants. I now find that the small and large ears belong to several quite distinct types, of Cape barley; and that, so far as my experiments have gone, they will each give progeny uniformly “ true.” ‘ The extra-large-eared selections will be thoroughly tested ...in. duplicate, and if they come up to expectations the stock of seed from the best type will be multiplied as fast as possible. In Bulletin No. 32, published by the South Australian Department of Agriculture, an account appears of some very exact experiments and calculations conducted . with Cape barley by A. J. Perkins and his staff, at the Roseworthy Agricultural College. These investigations prove that there is considerable difference fin the average weight of the individual grains on the large ears as compared with those on the small ears, 859 grains taken wholly from IJin. heads being required in order to weigh 1 oz., and only 591 grains when taken from 4|in. heads, the actual average weight of an individual grain being 0-033 grams per grain on the IJin. heads, and 0-048 grams per grain on the 4| in. heads. Mr. Perkins’s experiments show conclusively that with Cape barley there is a distinct tendency towards larger and finer grains with every appreciable increase in the length of ear.

RYE, OR RYECORN.

This has grown well here ; the damp weather did not appear to affect, it much, while rust did not harm it in the least. Three apparently separate forms were found, and one of these, having extra large ears, has been selected for growing separately next summer. The largest ear from the best plant, only was harvested. , ‘ Rye is- somewhat difficult to handle, as , compared with wheat,. oats, or barley, owing to the ease with-which it can cross-fertilize, and consequently all selections need to be ' completely isolated from each other and from all other rye crops when planted the following seasons.

“ CENTGENER-POWER ” TESTS.

These were initiated with all the 1908-9 cereal selections having a sufficient number of grains ; but, as the abnormal weather-conditions damaged numerous plants, the tests in most cases had to be abandoned, and therefore the comparative cropping-ability of. the various selections carried over will not be definitely known until'another season'has been experienced.

LUCERNE, OR ALFALFA, SELECTIONS.

The seed saved from the seven forms isolated in 1908 was sown in small plots under uniform conditions last spring.

Unfortunately, so far none of these have come up to expectations, as they do not show • any exceptionally good qualities, but they are all undoubtedly quite distinct types of lucerne. The white-flowered type (08213), with its specially succulent stems, is the only one having indications of a distinct advantage. Some fifteen fresh selections have been taken- from a quarter-acre plot of the Provence variety, and will, it is hoped, show better results. All through last winter every variety of lucerne. badly cut, by frosts, and made very little growth during that: season, although 25° was the lowest temperature experienced. A

In a plot of the Turkestan variety,-one solitary plant appeared which did not seem in the least affected by the frosts or the bitterly cold winds, • while it grew very much better and kept quite 3 in. .taller than the surrounding plants. This unique plant (092) has been marked for further observation during the coming winter, and in the meantime seed has been saved from it, and will shortly be sown in a plot by itself. There is no doubt that lucerne is especially open to improvement by the •selection method of plant-breeding, nearly all the varieties of it at present in existence being made up of a number of these distinct types, of sometimes widely different agricultural value, and which will invariably breed quite “ true.”. -Several/authorities claim ..that. certain of these unit species are especially adapted for growing on high country, others for dry barren plains, and even some for undrained swamp land. Whether these extreme characters do exist remains to be proved, but there is undoubtedly a very wide range of variability among the innumerable lucerne types.

timothy (Phleum pratense).

Preparations are now under way to carry out some selection-work with this grass, it being universally agreed that timothy is made up of several types, of much-varying pastoral value. Most timothy-plants have a decided bulbous formation at the base of each stem, especially when growing on dry soils, and it is believed that because of this bulb the plants are soon eaten out and killed by the close grazing of sheep and horses.

’ The proposal is to plant out about J acre in rows a foot apart and 6 in. between-each plant, and to endeavour to secure a type which is minus the bulb.

If a fixed type of this character is discovered, it may lead to making timothy a much more valuable grass for sheep-country. A 10-acre paddock on this station was sown down about six years ago, with the usual mixture of grasses and clovers, including a fair proportion of timothy. Since then it has been very closely grazed by cattle, sheep, and horses, particularly the latter. .. At the present date only a very occasional

timothy-plant can be found among the. other grasses. So far as observed, none of these show much, if any, bulbous formation at the base, and it is just possible that this very quality is the reason for their survival. Acting on this supposition, twenty-five plants have been transplanted from the field to the breeding-plots, and if any of them refuse to form bulbs when allowed to reach natural maturity, seed will be saved and extended sowings made. •

birdsfoot-trefoil. (Lotus corniculatus).

This useful , pasture-plant is fairly common all over the grazing-pad-docks here, mainly towards the bottoms of gullies and in swamps. It is composed of . several forms, three of which are showing up quite distinct on this farm. y. ' ■ ’ ■ • . ! .

One in particular (08216) appears to be a very strong grower, some of its plants measuring 6 ft. in-diameter. Roots of this form were secured, and planted alongside a plot of . the common' birdsfoot. trefoil for further comparisons. ■ . ' . -

So far the selected form seems to have advantages/ it having produced a much larger amount of herbage, which seems also of a rather finer quality. In habit the plants are extremely prostrate, while the stems are long and very thin, with numerous'exceedingly. small leaves. Seed has been saved from'the best plant of this promising type,'and will shortly be sown, in a plot by itself. ’* ■.. . : ■ SUMMARY. ' ■ ' ' ‘ ' ’ , _ In summarizing the results from the past eighteen months’ work at Moumahaki, and taking the most conservative view possible, it can be said that with oats there are indications that the grain of the common Algerian will be improved upon without sacrificing that-variety’s almost unique rust-resisting powers. . ’ ■' ' ••

The wheat-selections show promise in the direction of ■ stiffer ' straw, better grain-holding ability, and increased yield.

And, although the malting-barley selections have so far proved failures, yet several of those from Cape barley give good prospects of a decided increase in yield and an improved quality of grain. The rest of the work shows exceedingly interesting results, but is not yet sufficiently advanced to warrant any definite conclusions. •