bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Frego Bract on the Incidence of Cotton Boll Rot1
Authors: Jones Jack E. , Andries John A.
Published: July 2010

Near‐isogenic populations of frego and normal bract biotypes on each of three varieties of Gassypium hirsutum L. were compared for relative incidence of boll rot in replicated field experiments for three years at several locations in Louisiana. The frego bract biotype of each variety in each year and at each location had significantly less boll rot than its related normal bract strain. The association of frego bract with reduced incidence of boll rot was consistent with the varieties tested at all locations where comparisons were made.
Inheritance of Foaming Properties of Plant Extracts of Alfalfa1
Authors: Rumbaugh M. D.
Published: July 2010

In vitro foam tests of plant extracts were used to study the inheritance of bloat‐inducing qualities of alfalfa (Medicago sativa L. and M. falcata L.) in a 12‐clone diallel cross. General combining ability and general combining ability by year interaction effects were significant sources of variation. Heritability estimates obtained by doubling the regression of cross progeny array means on corresponding parent values and by regression of the self progeny means on the parent values both equaled .73. Significant differences in foaming volume also were detected among Selected open pollinated progenies of 35 plant introductions. It was concluded that varieties with low foam volume and possibly reduced danger of bloat to grazing ruminants could be developed by recurrent selection procedures
The Black Layer and Grain Maturity in Corn1
Authors: Daynard T. B. , Duncan W. G.
Published: July 2010

At maturity a black closing layer develops in the placental region of corn (Zea mays L.). The suitability of this black layer as an indicator of physiological maturity was studied in four hybrids of a range in maturity. As viewed by the naked eye the layer developed in 3 days or less, and its appearance coincided with the achievement of maximum kernel dry weight. An examination of a wide range of genotypes indicated that the black‐layer formation is a common feature of commercial hybrids at maturity.

An investigation of incompletely developed florets on partially barren ears or in the tip region of normal ears revealed black‐layer formation in those showing limited endosperm development. No black‐layer development was seen in nonfertilized or parthenocarpic florets.

The cause and mechanisms of black‐layer formation are unknown. However, it is speculated that such development is related to assimilate movement into the developing floret.
Genetic Differences in Soybean Trypsin Inhibitors Separated by Disc Electrophoresis1
Authors: Singh Laxman , Wilson C. M. , Hadley H. H.
Published: July 2010

The acid‐soluble whey proteins from seeds of several varieties of soybeans were analyzed by disc electrophoresis. Almost all varieties had a very intense protein band just behind the front which corresponded with the major band of commercial soybean trypsin inhibitor. The lines L63‐9485 and T‐245 lacked this band, but had a slightly slower moving band. The F1 seed of reciprocal crosses between L63‐9485 and Clark possessed both intense bands, while the F2 seed segregated to show one or the other or both bands. The gels were sliced and extracted with buffer. Trypsin inhibitor was recovered from the area of both intensely stained bands.
A Second Locus Controlling Red Testa in Peanuts, Arachis hypogaea1
Authors: Ashri A.
Published: July 2010

A second locus controlling red testa was discovered in a selection of peanuts from East Africa, which originated in Bolivia. Apparently in this locus the allele responsible for red testa is recessive, and it does not behave as a duplicate gene of the known R. There is indirect evidence that a D gene is required for the expression of this new red testa factor. It is not known if any F gene is required.
Meiotic Bahavior and Sterility in an Avena Pentaploid Hybrid: C.I.7232 (2n=28) ✕ Mesdag (2n=42)1
Authors: Forsberg R. A. , Wang S. , Shands H. L.
Published: July 2010

A 1959 report3 that the interploidy cross [Avena saliva L. var. ‘Black Mesdag’ (2n=42)] ✕ [derived‐tetraploid C.I.7232 (2n=28)] resulted in highly fertile F1 hybrids and derivatives generated considerable interest and skepticism because such behavior was contrary to that expected. This led the current authors to make the reputed cross and to determine the meiotic and agronomic behavior of F1 plants. All F1's possessed 35 chromosomes and were sell‐sterile, indicating that tetraploid C.I.7232 was not a parent of the earlier hybrids.
Comparison of Selection Based on Yield of Topcross Progenies and of S2 Progenies in Maize (Zea mays L.)1
Authors: Horner E. S. , Chapman W. H. , Lutrick M. C. , Lundy H. W.
Published: July 2010

Three methods of breeding for higher grain yield in maize (Zea mays L.) were compared: (a) recurrent selection for combining ability with the parental population (Parental Tester method), (b) recurrent selection for combining ability with an unrelated inbred line (Inbred Tester method), and (c) recurrent selection for yield of S2 progenies per se (S2 Progeny method).

After three cycles of selection for grain yield had been completed with each of the three methods, the nine resulting selected populations were evaluated for grain yield (a) as random‐mated populations (synthetics), (b) as selfed populations (bulked S1 lines), and (c) in crosses with 11 unrelated testers. Significant differences among the breeding methods were noted for the second and third cycles of selection, but not for the first cycle. The Parental Tester method produced the highest yielding random‐mated (syn‐3) population; whereas the S2 Progeny method produced the highest yielding selfed population. Average combining ability with unrelated testers for all three methods was increased significantly (5.2%) by the second and third cycles of selection, but there was no significant difference among methods. Although the Inbred Tester method resulted in significant improvement in yield of selfed populations, it was inferior to the other two methods for population improvement in the over‐all evaluation.

Selfing one generation resulted in over 70% reduction in yield of the first cycle populations, which indicates that dominance is of considerable importance in the base population. Inbreeding depression was progressively less drastic in the second and third cycle populations, particularly with the S2 Progeny method.
Reciprocal Translocation in Guar, Cyamopsis tetragonoloba (L.) Taub.1
Authors: Kinman M. L. , Bashaw E. C. , Brooks L. E.
Published: July 2010

Semisterility in guar, Cyamopsis tetragonoloba (L.) Taub., segregated in a 1:1 ratio and was found to be due to a reciprocal translocation. We conclude that the low chromosome number (n = 7), differences in size of chromosomes, and ease of staining make guar one of the few legumes suitable for karyotype and cytogenetic analyses.
Maturity and Yield of Seedflax in Controlled Environments: Effects of Root Environment1
Authors: Dybing C. Dean
Published: July 2010

In controlled environment studies with flax (Linumusitatisslmum L.), plants grown in aerated nutrient solution flowered in cycles, produced more than one set of bolls, anti often retained much green leaf and stem tissue when harvested at 90 days of age. Plants receiving the same total nutrient application, but grown in vermiculite watered with nutrient solution, produced only one set of bolls and then senesced. Senescence of plants in vermiculite was delayed slightly by an increase in the depth of the container in which the plants were grown and by 13hr photoperiod as compared to 19‐hr photoperiod. Maturation of ]plants grown in liquid culture was retarded by cooling the root zone to 15 or 20 C in an aerial environment with 30/20 C day/night temperature.

Seed and oil yields per plant were reduced by increased number of plants per pot, increased osmotic pressure of the nutrient solution, reduced root zone volume, and reduced root zone temperatures. Seed weight (g/l,000 seeds) and oil content were reduced by 15 C root zone temperature and by 10 arm osmotic pressure. Iodine value of the oil was only slightly influenced by root environment. Plants grown in liquid culture medium were more affected by aerial environment than plants grown in vermiculite.
Morphological and Chemical Characteristics of Inbred Lines of Tall Fescue Selected for Palatability to Cattle1
Authors: Buckner R. C. , Burrus P. B. , Todd J. R.
Published: July 2010

Three tall fescue (Festuca arundinacea Schreb.) inbred lines, previously selected for their improved palatability to cattle, were compared for crude protein, total sugars, silica, and several morphological characters when grown in a spaced‐plant nursery during 1964‐1967. Significant differences were found between parents and their S3 or S4 progenies for all chemical constituents studied. while previous studies indicated that the lines were characterized by improved palatability (4), the cattle apparently did not select high or low content of crude protein, silica, or total sugars

Variability of S4 lines for the three chemical constituents indicated the possibility of developing cultivars higher in total sugars and lower in silica than S0 parents.

Inbreeding depressed the number of panicles per plant, seed per panicle, culm height, panicle and ray length which resulted in reduced yields of forage and seed of the S3 and S4 lines.

It was concluded that four generations of inbreeding in tall fescue were probably sufficient to attain the desired uniformity for the characters studied.
Determination of Total Available Carbohydrates in Forage Legume Roots by Extraction with Takadiastase, Amyloglucosidase, or Sulfuric Acid1
Authors: Greub L. J. , Wedin W. F.
Published: July 2010

Takadiastase (“Clarase 900”), amyloglucosidase (“Diazyme 160”), and a combination of the two enzymes were compared with and without acid hydrolysis of the filtrates for the ability to extract sucrose and starch and convert them to reducing sugars in the determination of total available carbohydrates (TAC). Sucrose, soluble starch, and alfalfa root samples varying in TAG content and ratio of sucrose to starch were used as substrates. Comparisons also were made between TAC values obtained by the enzyme combination and by O.2N H2SO4. Clarase 900 recovered significantly more sucrose but significantly less starch than did Diazyme 160 or the enzyme combination. A mild acid hydrolysis subsequent to the enzyme stage enhanced sucrose recovery but not starch recovery.

When used on the root material without acid hydrolysis, the Clarase 900 and the enzyme combination gave similar TAC values. Diazyme 160 values were significantly lower than the other two treatments. Acid hydrolysis of the enzyme filtrate increased the TAC values of most of the root samples.

The enzyme combination method gave TAC values up to three‐fold higher than the 0.2N H2SO4 method when legume root samples were high in starch content, but the acid method gave higher values when TAC were low.
Liquid Pollination of Alfalfa, Medicago sativa1
Authors: Binek A. , Bingham E. T.
Published: July 2010

Alfalfa pollen was treated 5 to 120 rain before pollination with four liquid solutions: deionized water, 50 ppm boric acid solution, 10% and 20% sucrose solutions in 50 ppm boric acid. Pollen in liquid was condensed to a slurry by absorbing excess liquid and applied to stigmas of male‐sterile clones in a small concave spatula. Pollen from the four liquid solutions was equally effective in pollinations. Average seed set per 100 flowers obtained from pollen treated for 5, 10, and 20 rain was 386, 322, and 265 seeds, respectively. Seed set per 100 flowers after control pollinations was 534 seeds. The decrease of the seed set as the time of treatment increased was related to an increase in pollen germination prior to pollination. It appeared that only ungerminated pollen functioned in fertilization. Liquid pollination was also effective for diploid alfalfa. Use of liquid pollination, which allows treatment of the male gametophyte with various chemicals, was discussed.
Early‐Spring Blue Grama Inflorescences from Fall‐Initiated Spikes1
Authors: Launchbaugh J. L. , Hackerott H. L.
Published: July 2010

Blue grama (Bouteloua gracilis (H.B.K.) Lag. ex Steud.) was discovered flowering less than 1 month following severe winter weather, and 2 months before the normal onset of heading in native range near Hays, Kans. Variable spike damage was an indication of freezing or drought injury to the inflorescences during early development. The short interval between start of growth and spike exertion under field and experimental conditions suggests the early spikes were initiated the previous fall, started to develop, went into winter dormancy, and completed development during the earliest favorable growth period in the spring.
Further Isozyme Differences Among the Inbred Parents of a Reciprocal Recurrent Selection Population of Maize1
Authors: Brown A. H. D. , Allard R. W.
Published: July 2010

Four additional isozyme differences among the I2 inbred parents of two reciprocal recurrent selection populations (A and B) of maize arc described. Some common problems in the resolution of mobility differences are exemplified by the properties of these systems. Evidence is cited which shows that the mobility differences between single bands in these systems arise from codominant allelic variation at single loci. Data are reported concerning the linkage relationships of these four loci with each other, and with five previously described isozyme loci. Individual seedlings can be scored for all nine loci simultaneously, and therefore can be assigned to one of many thousand potential genotypic classes in monitoring the genetic effects of this selection regime.
Semigametic Production of Haploids in Pima Cotton1
Authors: Turcotte E. L. , Feaster Carl V.
Published: July 2010

Semigamy is a type of fertilization in which a sperm nucleus penetrates the egg cell but does not fuse with the egg nucleus. The egg and sperm nuclei divide independently, resulting in a heterogeneous embryo.

Haploids sectored for maternal and paternal tissue were obtained among F2 progenies of crosses of a semigametic line of Pima cotton (Gossypium barbadense L.), as female, with recessive multiple‐marked stocks. Truebreeding lines of paternal origin were obtained by colchicine doubling of paternal sectors of certain chimeral haploids. Thus homozygous lines of selected parentage were produced.

Semigamy was controlled genetically and transmitted through both the egg and pollen but was functional only if the egg nucleus contained the factor or factors that condition it.

The development of a semigametic, marked stock widened the scope of material from which haploids can be produced effectively.
Specific Gravity of Corn Stem Sections1
Authors: Thompson D. L.
Published: July 2010

Specific gravity (dry), i.e., dry weight/green volume, of 50‐mm stem sections of corn (Zea mays L.) was significantly correlated with stalk lodging, stalk rot rating, crushing strength, rind thickness, and puncture rating. Dry weight of sections was similarly correlated. Two other types of specific gravity (green and absolute) were generally not as well correlated. Specific gravity and dry weight evaluations were obtained approximately 1 month after pollination, were determined independntly of lodging stress, and were useful measures of stalk strength.
Physiological and Biochemical Diferences in Deteriorating Barley Seed1
Authors: Anderson James D.
Published: July 2010

New and aged seed lots of four barley (Hordeum vulgate L.) varieties were used to evaluate physlological and biochemical differences (percent germination, shoot growth, sensitivity to accelerated aging, respiratory rates, and amylase activity) in deteriorating seeds. Natural aging decreased percent germination in two varieties but caused little or no difference in the others. Only small differences (0 to 16%) were found in shoot length between the seedlings from new and old seeds. The older seeds were most sensitive to accelerated aging than newer seeds, even when no differences were found in percent germination or shoot growth. Oxygen uptake varied and did not seem to correlate with either percent germination or age. Older seeds evolved up to 200% as much CO2 as newer seeds, and had higher respiratory quotient's (RQ). After 36 hr germination newer seeds showed 46 to 67% more total amylase activity than older seeds
Effect of Different Cytoplasms on Oil, Fatty Acids, Plant Height, and Ear Height in Maize (Zea mays L.)1
Authors: Garwood D. L. , Weber Evelyn J. , Lambert R. J. , Alexander D. E.
Published: July 2010

Plant‐to‐plant reciprocal crosses were made between the maize (Zea mays L.) strain Illinois High Oil (IHO) and each of seven maize inbreds plus the strain Illinois Low Oil (ILO). Oil analysis showed that the direction of the cross caused the oil content of F1 kernels to vary an average of 3.00%. Paternal effects were of similar magnitude. These effects relate to differences in proportion of germ, percent oil in the germ, and fatty acid distribution in the whole kernel. To separate the physiological influence of the female parent from that of the cytoplasm it contributes, we examined F1 plants and, in a 2‐year study, F2 kernels differing only in their cytoplasm source. Oil content, ear height, and plant height were affected in some IHO ✕ lme reciprocal hybrids, but there was no effect on fatty acid composition. Because the largest cytoplasmic effect on oil was 0.14%, we concluded that the physiological influence of the female parent was responsible for the 3.00% maternal effect.
Gene Effects for Grain Protein in Five Spring Wheat Crosses1
Authors: Chapman S. R. , McNeal F. H.
Published: July 2010

Six generations — P19 P29 F19 F29 B19 and B29 — of each of five spring wheat (Triticum aestivum L.) crosses were employed in the evaluation of gene effects in the inheritance of grain protein by using Hayman's model for the analysis of generation means. Significant epistasis was absent in all crosses. The additive genetic effect was highly significant for all crosses. In only two of the five crosses was the dominance effect significant. These results indicate significant potential for improving grain protein percent through selection.
Simplification of the Dry Matter Disappearance Technique to Estimate Forage Quality1
Authors: Kendall W. A. , Todd J. R. , Templeton W. C.
Published: July 2010

The technique to determine percent dry matter disappearance (DMD) with a solution of 0.2% pepsin 0.075 N HCI was simplified by eliminating the pepsindigestion apparatus and by using paper in place of glass filters. These changes produced lower DMD values for all forages tested, but with suitable changes in the equation for calculating the Nutritive Value Index, the final results were identical.
Performance of Diallel Crosses of Bromus inermis for Forage Yield1
Authors: Dunn G. M. , Wright J. A.
Published: July 2010

Six open‐pollinated clones of Bromus inermis were evaluated in a diallel cross. The objectives were to compare the first and second synthetic generations in broadcast plots for forage yield and to obtain information on combining ability. The syn‐2 generation usually did not exceed ‘Saratoga’ for forage yield, but the single crosses generally showed improvement for resistance to brown leafspot and leafiness. The average yield in syn‐2 was approximately 90% of the syn‐1 generation for a 3‐year period in two different tests. Significant variances were obtained between years, generations, crosses, and for the cross ✕ generation interaction. Most of the gnetic variance appeared to be additive since the variances due to general combining ability were usually significant in both synthetic generations whereas those due to specific combining ability were rarely significant.
Inheritance of Field Reaction to Soil‐Borne Wheat Mosaic Virus1
Authors: Dubey S. N. , Brown C. M. , Hooker A. L.
Published: July 2010

A five‐parent incomplete winter wheat diallel cross was studied for inheritance of field reaction to Soil‐ Born Wheat Mosaic Virus (SBWMV).

Resistance was found to be monogenic dominant over both susceptibility to mosaic and to mosaic‐rosette, and susceptibility to mosaic was, likewise, monogenic dominant over mosaic‐rosette susceptibility. The results were interpreted on the basis of the operation of a multiple allelic series consisting of three alleles, viz, (1) Rmr which governs resistance to mosaic and mosaic‐rosette, (2) γm which is recessive to Rmr and conditions susceptibility to mosaic but is resistant to the rosette phase and (3) γmr which is recessive to both Rmr and γm and is responsible for mosaic‐rosette susceptibility.
Herbicides for Spring Establishment of Crownvetch (Coronilla varia L.)1
Authors: Elkins D. M. , Leasure J. K. , Faix J. J.
Published: July 2010

Several herbicides were effective in reducing stands of weeds and increasing the stand of spring‐seeded crownvetch (Coronilla varia L.) during the year of seeding. Trifluralin, benefin, EPTC, and vernolate generally eliminated most weed competition without injuring crownvetch. Dalapon, bromoxynil, 2,4‐DB, atrazine, SD‐ 15418, terbacil, and linuron gave ineffective broadleaf or grass weed control or injured crownvetch.
Artificial Selection for Seedling Drouth Tolerance in Boer Lovegrass (Eragrostis curvula Nees)1
Authors: Wright L. Neal , Jordan Gilbert L.
Published: July 2010

Artificial selection and evaluation of boer lovegrass (Eragrostis curvula Nees), were conducted with a program‐controlled environment at the Tucson Plant Materials Center. Plants from 16 sources were stressed for seedling drouth tolerance, and 216 surviving plants were progeny evaluated. Experimental 3‐17 showed significantly higher survival than any other selection and exhibited three times the seedling drouth tolerance of A‐84. Evaluation under artificial conditions of growth was repeated for the extreme selections and relative ranking of the selections did not change. These findings confirmed the use of program‐controlled environment for consistent evaluation of large numbers of seedlings and for precise selection of superior genotypes.

The usefulness of this technique to select genotypes with superior seedling drouth tolerance was demonstrated by performance under natural environments of rangeland seeding trials. Evaluations of experimental 3‐17, A‐84, and A‐68 lehmann lovegrass (E. lehmanniana Nees) were conducted on a limited basis at Pima, Ariz. in 1967 and more extensively in 1968 at several sites in southeastern Arizona. Stand density under natural environments of rangelands of experimental 3‐17 was superior to A‐84 and its seedling drouth tolerance was equal to that of lehmann lovegrass for all sites in the Southern Desert Shrub of Arizona.
Cleft Grafting Alfalfa1
Authors: Bernardo E. N. , Sorensen E. L. , Painter R. H.
Published: July 2010

Reciprocal grafts were made between pea aphid‐resistant and susceptible alfalfa clones. A median longitudinal slit about 2 cm long was made on the stock into which a wedge‐shaped scion was inserted. Coarse cotton thread was tied around the grafted parts to hold them together firmly. Masking tape was wrapped around the graft to minimize moisture loss from the cut surfaces. All the 112 grafting attempts were successful.
New Methods of Utilizing Wheat and Rye Germ Plasm in Triticale Breeding1
Authors: Sisodia N. S. , McGinnis R. C.
Published: July 2010

Two new methods of Triticale breeding are proposed viz. (i) Hybridizing the sterile F1 hybrids (ABDR) obtained from hexaploid wheat, Triticum sp. (AABBDD) ✕ rye, Secale sp. (RR) crosses with hexaploid Triticale (AABBRR) and (ii) crossing the pentaploid wheat (AABBD) ✕ rye (RR) sterile hybrids with AABBRR. Cytological screening of progenies for desired chromosome types and/or selection of more fertile Triticale‐like plants should result in the derivation of stable hexaploid Triticale lines. These methods, thus, eliminate the need of synthesizing wheat ✕ rye amphiploids as a means of introducing variability in the breeding populations. Because these methods greatly reduce cytological work and have other desirable features, they should be useful for rapidly improving Triticale even where laboratory facilities are minimal.
Alfalfa Chromosomes. I. Pachytene Karyotype of a Diploid Medicago falcata L. and Its Relationship to M. sativa L.1
Authors: Gillies C. B.
Published: July 2010

Chromosomes from the pachytene stage of meiosis in diploid Medicago falcata L. were used to construct an idiogram showing mean chromosome lengths, arm ratios, and the number and distribution of chromomeres. The total length of the haploid chromosome complement was 277.9 microns, with the chromosomes ranging in length from 41.2 to 25.7 microns. The shortest chromosome was the nucleolus organizer chromosome. Six chromosomes had median or submedian centromeres; two were acrocentric, having arm ratios of 2.71 and 3.71. The idiogram was similar to published idiograms of diploid M. sativa L. Using the M. falcata idiogram and the published idiograms of diploid M. sativa, a description was suggested for an idiogram common to all diploid alfalfas.
Seed Set in Indiangrass, Sorghastrum nutans (L.) Nash, Estimated by X‐Ray Photograph1
Authors: Barnett F. L. , Rafii Zia E.
Published: July 2010

Estimates of seed set of indiangrass, Sorghastrum nutans (L.) Nash, were slightly higher with x‐ray photography than with the rubbing‐board method. However, the two methods agreed closely in relative seed set of different strains. The low x‐ray dosage had no apparent effect on seed germination.
Soil Moisture and Temperature Effects on Growth and Soluble Carbohydrates of Orchardgrass (Dactylis glomerata)1
Authors: Brown R. H. , Blaser R. E.
Published: July 2010

Orchardgrass plants were grown at soil moisture levels of 10 to 30, 40 to 60, and 80 to 100% of available water in growth chambers set at 24‐18 C and 35‐29 C day‐night temperatures. Plants from each treatment were harvested at 3, 7, 12, and 18, days after start of the moisure regimes. Final yields were twice as great for the high as for the low moisture level. Yield at 35 C was about 1,/2 as much as at 24 C. Increases in tiller numbers were favored by the 24 C temperature and high moisture level. No new tillers were produced at 35 C. Increases in tiller weight were similar at 24 and 35 C, but were much less at the low than at the high soil moisture level. Moisture stress increased soluble carbohydrate in stem bases. Growth rate and soluble carbohydrate content were inversely related. Moisture stress, expressed as percentage of dry matter in the fresh material, was directly related to soluble carbohydrate content. It is concluded that the buildup of soluble carbohydrate under moisture stress is due to a greater reduction in utilization than in synthesis of photosynthetic products.
Effects of Genetic Heterogeneity Within Two Soybean Populations. II. Competitive Responses and Variance Due to Genetic Heterogeneity for Nine Agronomic and Chemical Characters1
Authors: Byth D. E. , Caldwell B. E.
Published: July 2010

Effects of genotypic heterogeneity within relatively homozygous lines of soybeans evaluated in three environments were essentially additive for most traits when averaged over populations of lines within a cross. This was related to equivalence of competitive advantages and disadvantages expressed by genotypes within these populations of heterogeneous lines; that is, competitive effects were compensatory.

Such additivity apparently held, on the average, for individual heterogeneous lines in the simpler agronomic and chemical characters. However, effects of heterogeneity on character development were non‐additive in individual lines for yield, height, and seed size. Differential responses for characters and crosses were related to differences in the degree of heterogeneity within the lines. In general, interactions among relatively diverse genotypes conditioned more extreme responses, and interactions among relatively similar genotypes conditioned less extreme responses than expected, on the basis of additivity of genotypic effects.

Substantial over‐ and under‐compensatory competitive responses occurred for yield, and competitive response was positively correlated with heterogeneous line performance in both crosses. Some implications of these responses, and potential biases introduced into bulk population breeding procedures as a result of their action, are discussed.
Water Requirement and Its Association With Growth Components and Protein Content of Alfalfa (Medicago sativa L.)1
Authors: Cole D. F. , Dobrenz A. K. , Massengale M. A. , Wright L. Neal
Published: July 2010

Two experiments were conducted in a greenhouse environment at Tucson, Ariz., to investigate the water requirement of five cultivars and two experimental lines of alfalfa (Medicago sativa L.) at the seedling and mature stage of plant development. Another experiment was conducted to investigate differences in water requirement among genotypes within the cultivars ‘Mesa‐Sirsa’ and ‘Ladak.’

Significant differences were found in water requirement among cultivars in both the seedling and mature stages of plant development. Significant differences were found among plants of different cultivars in dry forage and transpired water in the seedling stage; however, no significant differences for these factors were found among cultivars in the mature stage of plant development.

Greater variation in water requirement was found within cultivars than was found among cultivars.

Dry forage production, leaflet to stem and petiole ratio, leaf area, and percentage protein of stems and petioles were each significantly associated with water requirement when averaged over all cultivars.
Heritability Estimates of Quantitative Characters in Mung Bean (Phaseolus aureus Roxb.)1
Authors: Empig L. T. , Lantican R. M. , Escuro P. B.
Published: July 2010

Heritability (broad sense) estimates of nine quantitative characters were obtained in the F2 of five crosses of mung bean strains. The estimation procedure used was the direct method wherein environmental variance was approximated with the use of the parents. Days to maturity had the highest heritability estimate with a mean of 71.2% for the five crosses. Mean estimate of heritability of 8.6% for seed yield was the lowest.

In the F3, heritability (broad sense) estimates for seed yield and its components, namely, pods per plant, seeds per pod, seed weight, and seeds per plant were calculated by variance component analysis in one of the five crosses. Seed weight had the highest estimate of heritability which was 85%, whereas number of seeds per plant had the lowest value of 26%. Seed yield had an estimate of 47%.

Based on the F2 data, maturity range had the highest expected genetic progress (37% of the mean) obtainable by selecting the top 5% of the F2 progenies. Seed yield had only 5% expected genetic progress.

The implications of these results to breeding programs designed to maximize yield levels in mung bean were discussed.
Genetic Control of a Photoperiod—Temperature Response for Time of Flowering in Beans (Phaseolus vulgaris L.)1
Authors: Coyne Dermot P.
Published: July 2010

In the first experiment conducted in the field on the inheritance of date of flowering in the cross between the early flowering ‘G.N. 1140’ and the late flowering PI 165078 cultivars of Phaseolus vulgaris L. it was found that this trait was controlled primarily by a single major gene with late flowering being recessive. The symbol fd was assigned to this recessive gene.

In a second experiment conducted in growth chambers it was observed that PI 165078 flowered at a later date than G.N. 1140 when grown under long days (14 hours), and 29.4 C and 26.7 C (day and night) temperatures, but that there was no significant difference in date of flowering of the varieties under the 14‐hour photoperiod, and 26.7 C and 21.1 C. The increase in temperature under a 14‐hour day produced a differential response in date of flowering of the varieties.
Oat Varietal Differences in Length of Lower Internodes1
Authors: Nittler L. W. , Kenny T. J.
Published: July 2010

Six oat, Avena sativa L., varieties grown in sand in a growth chamber were supplied with a complete nutrient solution. Consistent and highly significant varietal differences developed in length of internodes. Although length of internodes was affected by photoperiod, temperature, age, spacing, and planting depth, this is not considered a serious obstacle to use of internode length in varietal purity testing provided environmental conditions can be controlled.

Plants of the ‘Russell’, variety grown with continuous light and a temperature of 27 ± 2 C had first leaf internodes (above the first foliar leaf node) three to five times as long as those of other varieties. Second leaf internodes of ‘Orbit’ were nearly twice as long as those of ‘Garry’ or ‘Niagara.’ Both Orbit and ‘Rodney’ had long third leaf internodes whereas ‘Clintland’ had the longest fourth leaf internodes.
Yields and Chemical Composition of Timothy (Phleum pratense L.) Plants Derived from Summer and Winter Tillers1
Authors: Knievel D. P. , Smith Dale
Published: July 2010

Summer (nonvernalized) and winter (vernalized) timothy (Phleum pratense L.) tillers were grown at 18 C day/10 C night temperatures and harvested at anthesis. Inflorescence production and canopy heights were similar for both plant types, but the summer plants reached anthesis 12 days later. Yields of green leaf‐blade, stem plus sheaths, stem base, root fractions, and total plant dry matter accumulation rate of the summer plants were significantly greater than corresponding parameters of winter plants. Similarly, number of leaves and green leaf‐blade area per pot were significantly greater for the summer plants.

Percentages of total nonstructural carbohydrates and fructosans were significantly higher in the summer plant parts, while percentages of total N were significantly higher in the winter plants. Reducing sugar, sucrose, starch, nitrate N, and crude fat percentages were similar among plant parts and between plant types. In vitro digestible energy of the primary shoot green leaf‐blades and of the primary and secondary shoot stems was significantly higher for the summer plants. In vitro digestible energy of the green leaf‐blades on the secondary shoots was similar for both plant types.
Effects of Selection for Lower Ear Height in Synthetic Populations of Maize1
Authors: Vera G. A. , Crane P. L.
Published: July 2010

Two populations of maize (Zea mays L.) [Antigua 2D ✕ (B10 ✕ B14)] F5 and (Eto ✕ CBC) F5 were used a selection experiment conducted at Lafayette, Ind., to determine the effectiveness of 50% selection intensity in lowering ear height. These two populations were subjected to two cycles of selection, each followed by a generation of random intermating in Florida. The lowereared 50% of the plants in each day of silking was selected to avoid confounding selection for ear height with date of flowering.

The evaluations of the subpopulations per se derived by selection and the topcrosses of these subpopulations with five single‐cross testers were made in three locations in 1968.

The results showed that selection was effective in lowering the ear height 4.5% per cycle. There was no effect on percent moisture. A slight reduction in yield and a more pronounced reduction in percent lodging were statistically nonsignificant.
Inheritance of Reaction to Toxaphene in Oats1
Authors: Gardenhire James H. , McDaniel Milton E.
Published: July 2010

The reaction of oats (Avena spp.) to toxaphene insecticide spray was found to be controlled by a single major gene, with susceptibility conditioned by the dominant allele. The effect of toxaphene appeared to be localized, and caused discoloration and eventual death of leaf tissue contacted by spray material. New growth appeared normal. The toxaphene chemical and not the solvent carrier appeared to cause the damage.
Genetic Linkage in Soybeans: Linkage Groups II and III1
Authors: Weiss Martin G.
Published: July 2010

Genetic linkage between the soybean loci P1, p1 (glabrousness, pubescence), and R, rm, r (black, black concentric striping, brown seed coat color) was verified in Linkage Group II and the combined recombination value was 20.9 ± 2.4%. Linkage intensity between the loci G, g (green, yellow seed coat color) and D1, d1, (one of two duplicate factors conditioning yellow, green cotyledon color) in Linkage Group III was determined to be 4.2 ± 0.6%.
Relation of Seed Yield and Fitness in Phaseolus Lunatus L
Authors: Tucker C. L. , Webster Barbara D.
Published: July 2010

Three genotypes of lima beans, Phaseolus lunatus L., were yield tested in order to determine whether yielding ability was related to competitive ability. Results indicated no relationship between yielding ability in a pure stand and survival ability in a bulk population.
Chromosome Translocation Set in Sorghum bicolor (L.) Moench1
Authors: Schertz K. F.
Published: July 2010

A set of homozygous translocation stocks in sorghum was developed. The 11 stocks represent at least two translocations involving each of the 10 chromosomes. The stocks were isolated in progenies from irradiated pollen and seed of cultivar ‘Combine 7078,’ and the chromosomes were designated by a sequence of intercrossing and cytological analyses. Chromosomal and fertility characteristics vary in plants heterozygous for these translocations.
Genetic Variation of Quality Traits in Maize (Zea mays L.) Forage1
Authors: Roth L. S. , Marten G. C. , Compton W. A. , Stuthman D. D.
Published: July 2010

Thirty‐six maize (Zea mays L.) single crosses and varieties were analyzed to determine if there was genetic variability for five forage quality traits: in vitro digestible dry matter, acid detergent fiber, acid detergent lignin, cell wall constituents, and crude protein. Significant genetic variability was found for all of the traits and all were intercorrelated, except for crude protein. The data indicated the feasibility of breeding maize varieties which would be superior (for silage quality) to varieties developed for grain yield alone.
Effect of Environmental Conditions on the Growth of Four Perennial Grasses. III. Nucleic Acid Concentration as Influenced by Day‐Night Temperature Combinations1
Authors: Baker Barton S. , Jung G. A.
Published: July 2010

Timothy (Phleum pratense L.), bromegrass (Bromus inermis Leyss.), orchardgrass (Dactylis glomerata L.), and Kentucky bluegrass (Poa pratensis L.) were grown under controlled temperatures varying by 3.3 C intervals from 18.3 to 34.8 C during the day and from 1.8 to 18.3 C during the night. The top growth was analyzed to determine the influence of these temperature regimes on ribonucleic acid (RNA) and deoxyribonucleic acid (DNA).

Day temperatures exhibited considerably more influence on the nucleic acids than did night temperatures. As the day temperature was increased from 18.3 to 34.8 C the RNA concentration decreased in a near linear manner. The decrease was 43% in timothy and between 21 and 27% in the other three species.

When grown at a day temperature of 18.3 C the RNA and DNA concentrations of orchardgrass and bromegrass increased as the night temperature increased. When grown at 34.8 C, however, the concentration of these two components decreased as the night temperature increased. With timothy and Kentucky bluegrass, night temperature had no appreciable influence on RNA, but the DNA concentration tended to increase as night temperature increased. It is proposed that the influence of day temperature on growth in the species used in this experiment may occur in part through its influence on nucleic acids while the influence of night temperature may occur through food reserves.
Some Chemical Properties of Hybrid Seed from a Cross Between Gossypium barbadense L. and Gossypium davidsonii Kell1
Authors: Lee Joshua A. , Smith F. H.
Published: July 2010

The diploid species Gossypium davidsonii Kell., has a slightly higher level of lysine in the seed than the tetraploid cultivated species, Gossypium hirsutum L and Gossypium barbadense L. It also has much more gossypol in the seed than either of the cultivated forms. Seed from a cross of G. davidsonii (as male) with a glandless accession of G. barbadense (as female) contained no more lysine than the female parent. Most of the other amino acids were, quantitatively, nearer the female parent than the male, and gossypol level was less than one‐third that of G. davidsonii. The data suggest that G. davidsonii will not be of much value for improving the protein composition of cultivated cottons, but might contribute some increase in gossypol where this substance is needed to control bollworms (Heliothis spp.)
Frequency Dependent Stability of Performance in Oats1
Authors: Qualset C. O. , Granger R. M.
Published: July 2010

‘Blount’ and ‘Forkedeer’ oats (Avena sativa L.) were studied in pure stands and two‐way mixtures with 25, 50, and 75y0 of each variety in 10 environments at four locations for 3 years. Four experimental lines were also included as pure stands. The grain yields of the mixtures were slightly higher and lodging percentages were significantly higher than predicted from the performance of the components. Stability was measured as repression and deviations from regression of population performance on environmental productivity and as the proportion of the populations ✕ environments variance. The mixtures were judged more stable than Blount or Forkedeer. Frequency dependency of stability for yield was indicated since the populations became increasingly more stable as the frequency of Blount was increased in the populations. The 75% Blount‐25% Forkedeer population offered advantages of stability with only slightly lower grain yield than Blount, the higher yielding variety.
Yield Reduction in Safflower Hybrids Caused by Female Selfs1
Authors: Urie A. L. , Zimmer D. E.
Published: July 2010

Fl hybrids of safflower, Carthamus tinctorius L., when grown in comparative yield trials with adapted varieties, outyielded ‘Ute,’ the highest yielding variety, by an average of 24%. Hybrids mixed with 16 to 43% female selfs (partial hybrids) failed to show the same superiority. Normal‐hull varieties containing mixtures of from 10 to 60% thin‐hull (females) failed to yield as much as the same varieties without the mixtures. As the percentage of thin‐hull plants increased in the mixture the yield decreased. Unless the competition resulting from the presence of low‐yielding selfs can be avoided, eliminated, or reduced, the maximum potential yield afforded by hybrids may not be realized.
Inheritance and Trisome Linkage of Seedling Characters in Sorghum bicolor (L.) Moench1
Authors: Hanna W. W. , Schertz K. F.
Published: July 2010

Segregation ratios of 24 seedling lethals in Sorghum bicolor (L.) Moench indicated that the characters were simply inherited.

Some of the genes controlling these characters were tested for linkage with specific chromosomes by using primary trisomic plants. F2 segregation ratios in progenies from crosses of trisomic ✕ genetic stocks showed that the gene w18 was associated with the bottle‐brush trisome and the genes w19 and w20 were associated with the cone trisome. The genes controlling coleoptile color (Rs1 and Rs2) were associated with the small‐glume and stiff‐branch trisomes, respectively.
Viability of Seed from Interspecific Crosses with Naranjilla (Solanum quitoense)1
Authors: Vivar H. E. , Pinchinat A. M.
Published: July 2010

Naranjilla (Solanum quitoense Lam.) lacks several of the agronomically desirable traits possessed by the less economically important S. hirsutissimum Stanley, S. hirtum Vahl, S. tequilense Gray, and S. topiro Humb. & Bonpl. These five species, according to routine cytological checks, showed a common somatic chromosome number (2n=2x=24), medium to high pollen viability (65 to 90%), and predominantly normal chromosome pairing at meiosis (12 bivalents). Reciprocal crosses between naranjilla and each of the other four species produced seed in all but two combinations (S. quitoense ✕ S. topiro and S. quitoense ✕ S. tequilense) but seed from only the crosses involving S. hirtum as one of the parents germinated. Moreover, percent germination of the S. hirtum ✕ S. quitoense seed was considerably higher (above 50%) than that of the reciprocal cross (below 0.5%). Nonviable hybrid seed looked thin and translucent, suggesting a lack of functional endosperm. Thus, special breeding techniques such as embryo culture may be required to successfully raise F1 plants from such seed.
Heritability and Genetic Advance for Kernel Weight in Barley (Hordeum vulgare L.)1
Authors: Borthakur D. N. , Poehlman J. M.
Published: July 2010

The winter barley variety ‘Mo. B‐475’ was crossed with the large seeded spring varieties, ‘Larker’ and ‘Trophy.’ Parents, F1, and F2 were grown in the greenhouse in the first experiment and parents, F1, F2, and F3 progeny lines were grown in the field in the second experiment. Heritability of kernel weight ranged from 25.3 and 25.9% when measured by parent‐progeny correlation to 43.1 and 46.0% when measured by variance of F2 (broad sense). Observed genetic advance ranged from 6.5 to 14.2% depending on the method of calculation and compared closely to the predicted.
Influence of Intact Tillers and Height of Cut on Regrowth and Carbohydrate Reserves of Dallisgrass (Paspalum dilatatum Poir.)1
Authors: Watson Vance H. , Ward Coleman Y.
Published: July 2010

Vegetatively propagated dallisgrass (Paspalum dilatatum Poir.) plants of a single clone were grown in the greenhouse and cut to a stubble height of 2.5‐ or 7.5‐cm in a factorial combination of leaving 0, 10, 20, or 30% intact tillers. Higher daily and total regrowth yields resulted from decreasing the height of cut or leaving intact tillers. Total available carbohydrates increased as height of cut and percent intact tillers increased. Translocation of carbohydrates from intact tillers to new growth was demonstrated by treating the uncut tillers with C14 sucrose, glucose, and fructose, and following their movement at various time intervals with autoradiographs. Apparently 10% more intact tillers are sufficient for dallisgrass survival and growth under intensities of defoliation used in these studies.
Selection for Seed Setting in Hybrid Populations of Autotetraploid Barley, Hordeum vulgare L. emend Lam.1
Authors: Kao K. N. , Reinbergs E. , Harvey B. L.
Published: July 2010

Selection for increased seed set was carried out in the segregating generations of four hybrid populations derived from intercrosses of five autotetraploid lines. The seed set of the early generations of the hybrid populations was higher than the respective parents and was maintained through the F5 to F10 generations. Selection, however, was ineffective in increasing the percentage seed set. The greater seed set of the hybrids was probably not due to heterosis unless a great deal of preferential pairing occurred. Selection was also carried out for reduced seed set and this was also ineffective. The lack of success in selection indicates a need to select on the basis of specific combining ability to improve the seed set of autotetraploid barleys.
Breeding for Seed Yield and Seed Quality in Smooth Bromegrass, Bromus inermis Leyss.1
Authors: Knowles R. P. , Cooke D. A. , Buglass E.
Published: July 2010

Considerable variation in seed production potentials was shown by polyeross progenies of selected clones of smooth bromegrass, Bromus inermis Leyss. Synthetics formed of clones with superior progenies yielded 30 to 40% more seed than northern common in regional tests. Seed volume weight was higher for synthetics than for northern common or standard varieties. Composites formed from reserve polycross seed produced less seed than synthetics, but were of predictive value for synthetic performance. Significant correlations of parent clones and polycross progenies for seed yield and seed quality suggested mass selection for initial improvement. High seed yields of selected clones were associated with a reduction in aneuploidy. No adverse effects on forage production resulted from selection for seed productivity.