16th Annual Report of the New Jersey Agricultural College Experiment Station for the year ending October 31st, 1903. 461-466

BYRON D. HALSTED, SC.D.
JAMES A. KELSEY, M.SC.. FIELD ASSISTANT.

Corn Breeding

The work in the Botanical Department for the year ending November 30th, 1903, has been chiefly along lines mentioned in the reports for the past few years.

Plant breeding has been a leading feature of the work in the field, supplemented by that of the greenhouse. During the year a new variety of sweet corn has been established, which resulted from crossing the "Black Mexican" upon the "Egyptian." This combination has produced a variety with good-sized plants, and ears of satisfactory size and number of rows of graining upon the cob. The color of the green corn when ready for market is a rich pink, and therefore especially attractive. Progress has also been made in developing a variety of corn that may have the grains mixed in the ear—pink and white—and with a special tendency to produce more than two ears to each plant. During the season a cross has been secured between the "Black Mexican" and the "Country Gentleman" for future development by selection.

PLATE I.
Four ears of Voorhees Red Sweet Corn, with one of the male parent, "Black Mexican," upon the left, and one ear of the mother plant, "Egyptian," upon their right.

EXPERIMENTS WITH SWEET CORN.

The experiments in the crossing of sweet corn began in 1898, by planting the following sorts in the same plot: "First of All," "Stabler's Nonpareil," "Stowell's Evergreen," "Egyptian" and "Black Mexican." Cross-fertilization took place freely between the "Black Mexican" and the "Egyptian," some ears of the latter showing fully one-half of the grains of a dark color, indicating the effect of the former variety, the only one that was not white. It was observed that the dark color was less impressed upon the crossed grains of the "Stowell's Evergreen" than the "Egyptian." This suggested that the "Black Mexican" was more potent upon the "Egyptian" than upon the "Stowell's Evergreen," and led to the selection of the first two named sorts for future breeding.

In 1899 Plot II., Series III., was planted again to sweet corn, there being a row each of the "Black Mexican" and ''Egyptian" in each of the six belts. The "Black Mexican" is a variety of medium stature of plant, and also medium in time of maturing, with eight- rowed ears and grain of good quality, but sometimes objected to because of the dark color. The "Egyptian" is a larger sort, with heavier ears and white grains, in ten to sixteen rows, maturing comparatively late, and of high quality.

During this first season of the cross not more than one grain in fifteen of the "Mexican" showed the influence of the "Egyptian.'' Five of the most affected ears gave a total of 1,093 black grains to 299 of white ones. There was more of the mixing upon the "Egyptian," as a corresponding five ears show black grains, 1,083, and white, 1,385. A comparison of the two sets of figures also shows the relative size of the ears of the two sorts. With the "Egyptian" crosses there were all gradations between the slightly purplish grains and those that were nearly as dark as those of the typical "Mexican," and many were of a rose or pale-red color. Occasionally a grain was found with one-half white and the other dark, and in a few cases the division line was along the narrow way of the grain and suggesting a birth-mark, covering one side of the face.

Experiments In 1900.

During the season of 1903 four plots were in sweet corn as a continuation of the crossing of the previous year. Plot IV., Series IV., was planted with pink grains from single ear of the "Egyptian" type. The good qualities of the two varieties under consideration stood in favor of the "Egyptian." For example: a ten or twelve-rowed variety is preferred to one with only eight rows, and for this and other reasons the above choice in the cross was made. This plot made a fine showing of strong corn plants, and from the ninety-six hills, 355 good ears were gathered, there often being two ears to the best stalks, and sometimes three or four. The ears were, without exception, remarkably uniform in the even mixing of the white and colored grains. Five average ears gave an average of 172 white grains to 213 that were colored. There is a blending of the two parent varieties in the shape of ear, number of rows, as well as in a large percentage of pink grains. The slender "Mexican" type is not fully maintained in even the few eight-rowed ears, the cob being larger, with the basal end somewhat swollen. The number of twelve-rowed ears exceeded all others, numbers which ranged from eight to sixteen showing that the mother plant ("Egyptian") had a very decided influence.

Experiments in 1901.

Plot IV., Series VI., was again planted to sweet corn, and the seed used was the pink grains from eight ears of the previous crop, and all having over ten rows upon the cob. The plants thus produced were remarkable for their vigor and size. At harvest time the first things observed was the greatly increased amount of red in the ears. The average of five typical ears gave 90 white, 81 black and 261 red grains. The number of grains per ear had increased considerably over the previous year, a feature of no small consequence when many rows is an advantage in sweet corn.

A greater variation in the ears was observed. In 1900 the ears were practically alike, but this season they ranged all the way from those with about half white grains to those in which the color was entirely red. It was also noted that nearly all the ears were more than eight-rowed, and this characteristic of the "Mexican" variety is largely lost from sight.

Experiments in 1902.

For the third successive season Plot IV., Series VI., was planted to sweet corn. From the previous crop a fine, solid-red, ten-rowed ear was selected and marked "X" ("Extra") at the time of harvest. For this some grains were taken, and a dozen plants grown in the greenhouse during the winter of 1901-2. Several ears were thus produced, all short, however, because of the unfavorable conditions for the best growth of corn, and from these, which were solid red, seed was selected for one-third of the plot, namely, belts 1 and 2. The remaining two-thirds of the plot was planted with grains from the ear marked "X"—that is, the mother ear of the greenhouse corn above mentioned. In other words, the whole plot was planted with the product of the same year; only the first two belts bore plants one generation further from the original cross of "Black Mexican" and "Egyptian." The greenhouse-grown seed produced smaller plants than in the other portion of the plot, a difference to be attributed to the poor conditions under which the seed was produced under glass. The ears, however, were not far below normal size.

At harvest time the first thing to be observed was the very large number of red grains, the average of five typical ears from the greenhouse seed being: white, 14; black, 0, and red, 373 grains; and of the same number of similar ears directly from the ear "X," white, 28: black, 0; red, 465. These figures show that the greenhouse grains produced less white kernels and somewhat smaller ears than the grain directly from ear "X."

It is seen that only a small percentage of white grains remains in this crop, which is from the planting of pink grains of a single ear of the "Egyptian" type in 1900.

The following table gives the number of rows for the best ears in the two portions of the plot.

No. of rows per ear Greenhouse Progeny Direct from Ear "X."
8 3 6
10 10 15
12 42 38
14 15 14
16 6 6
Total 76 79

A little more than half (80 in 155) of these ears have twelve rows, and this is a number that is satisfactory in sweet corn.

Experiments in 1903.

For the fourth year in succession Series 0 was planted to corn, each of the four plots receiving grains from separate selected solid red ears of the previous crop. The season was unusually unfavorable for corn, it being exceedingly dry at the proper planting time and throughout May, to be siicceeded by heavy rains in June and August, with winds that prostrated plants time and time again before harvest time. The yield was necessarily light, but from the size of the stalks and ears it was evident that under ordinary circumstances the crop would have been satisfactory. The number of solid red ears was very large, and seed has been selected from the best of these for future planting. Four sample ears are shown in Plate I., and upon the left is shown an ear of the male parent, ''Black Mexican," and upon the right, a corresponding car of the female parent, the "Egyptian." The former is blaek and the latter white, and the resulting cross red; the former is eight-rowed and the latter ten to fourteen, with which the cross agree in this respect.

The Director of the Experiment Station has kindly consented to the use of his name in connection with this new variety, and therefore it will be known as the "Voorhees Red Sweet Corn.''

Developing a Prolific Corn.

In 1901 a half of Plot III., Series IV., was planted somewhat late (June 28th), with grains taken from seven ears borne by three stalks of the cross-breed of the previous year. One of the stalks had three fine ears, while the other four of the seven ears were first-grade twins. The triplet had two ears with ten rows of grains and one ear with fourteen rows. One twin had eight and ten rows to the ear, respectively, while the other pair were both twelve-rowed. These ears were all quite uniform in the ratio of white to dark grains—that is, as 4 to 5.

The forty-eight hills from this seed, planted without, regard to color, yielded forty-four stalks with single ears, unusually large and invariably with ten or more rows; eighty-three stalks with two marketable ears, each with rarely less than ten rows, and seventeen stalks with three or more ears, among which was one with five ears, all over five inches long; one with six and one with seven ears, but of these only one or two were marketable. The total numljer of ears was 272, or nearly an average of two ears to each stalk, exclusive of many abortive attempts to produce more.

It is noted that the mixed red and white result is still maintained, but it is not as uniform for all the ears as in the previous year, as shown in the other engraving of the same plate. In 1931, in other words, some stalks show more white than others. The average number of rows of grains to the ear is ten, which is practically the same as for the ears from which the seed was taken for planting.

In 1902 a whole plot was given to a further study of prolific corn. Single-eared stalks were rarely met with, the main portion having either two or three ears. It is observed that the mixture of white and red grains is maintained, but some variation in ration among the four lots of ears. When a stalk bears more than three ears it is at a loss of commercial value of the product. There is difficulty in selecting seed for future planting, as there is a possibility of developing the tendency to produce ears beyond the limit of most profitable output of marketable ears.

During the present year Plot III., Series IV., was planted with "prolific corn," and the crop would have proved more satisfactory but or the very poor season. As it was, the late planting and heavy rains and windstorms gave a poor yield. There was a large percentage of stalks with two marketable ears, although many of them were small. There were strong indications of prolific-ness in stalks that had set three, four and even five ears, but usually they did not mature.

The ears at harvest showed a very even mixture of the white and pink grains, and by planting half of each of the two colors it may be possible to continue this mixture until it become a characteristic, so long as one or the other color is discarded in planting.

Crossing Corn—New Series.

Upon a half of Plot I. and the whole of Plot IV., Series VI., corn was again grown, but this time it was the beginning of a new series of crosses. The two varieties selected were the "Black Mexican" and the "Country Gentleman." The former has been used in the crosses with the "Egyptian," which gave rise, aided by selection, to the red sort that has taken the name of "Voorhees." It is, as often before stated, a black-grained variety, medium in size of plant and time for maturing, and with eight rows to the ear. It is of high quality and would be much more grown for the table were not its dark color an objection. The "Country Gentleman" is a white-grained sort, somewhat larger in plant and ear than the "Mexican," about two weeks longer in coming into bloom, and there are no well-defined rows, the numerous, long, pointed variable grains of high quality being very irregularly disposed upon the large cob.

In order to bring those two quite widely different varieties together and accommodate them as to time of blooming, they were planted in alternate rows, three rows apart, and after two weeks another similar planting, while the third planting, four weeks after the first, completed the plots.

The two sorts are easily distinguished as standing in the field, and one of the constant characteristics of the "Country Gentleman" was the handsome pink color of the silk, it being the white sort, while the "Black Mexican" had usually a pale green silk, although this is not constant, and some of the stalks bore pink silks—a variation that has been constantly met with in this variety.

There is little else to dwell upon for the present, except to show average ears of the parents and those in which the crossed grains are apparent from the mixture of the colors.


PLATE II.
Plate II. shows a set of ears of corn that represent the "Black Mexican," upon the left, and the "Country Gentleman," upon the right. The next ear upon the left is a "Black Mexican," with a few grains only that have resulted from pollination of the "Country Gentleman,'' and the ear next to the right shows a larger percentage of this crossing. The right of the two middle ears is a "Country Gentleman" that resulted from hand pollination, and all its grains show the dark color that this crossing with the "Black Mexican" produced. To the right of the last-named ear is one which shows the mixing that was quite general in nearly all the ears of this sort.

The "Black Mexican" is an eight-rowed variety, but it sometimes happens that this number is somewhat increased, as instanced in ear that is next to one of the "Country Gentleman." The ordinary ear, when broken, appears as shown in the plate. The much longer and narrower grains of the "Country Gentleman" are similarly shown. This latter sort has pearly white grains that are disposed without apparent order upon the cob—that is, there are no distinct rows. It produces a larger ear than the "Black Mexican," and the ear required, in this experiment, fully two weeks more for it to reach marketable size. This was a very unusual season, and any tests as to periods of growth are not conclusive. With us the planting was much delayed on account of bad weather, and later on heavy floods and very destructive winds nearly ruined the experiment. This accounts for the comparatively small ears that appear in the picture. The unusual season may account for a fact that was painfully apparent at harvest time, namely, that but very few of the "Black Mexican" ears showed any white grains due to the pollen of the "Country Gentleman," while, on the other hand, it was almost impossible to find an ear of the latter sort that did not have dark grains due to the pollen of the "Black Mexican," all of which prevented the ears in the plate from being up to the average of the meagre crop. As the matter now stands, the "Country Gentleman" is easily fertilized by the "'Black Mexican," while the latter is with rare instances crossed upon by the "Country Gentleman." In other words, the "Black Mexican" is highly prepotent, as determined in other experiments. It was observed that the dark grains of the "Country Gentleman" were not usually of the same shade as the full "Black Mexican," but instead inclined to a lead color. The white grains upon the "Black Mexican" were, with few exceptions, as light as those of the full "Country Gentleman."

The quality of the two varieties is superior, as determined by actual test by those who are able to judge of the culinary merits of this vegetable.