bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Method of Using Interchanges as Chromosome Markers1
Authors: Burnham C. R. 
Published: July 2010

A new method of utilizing interchanges as chromosome markers which will require one less than the n number of chromosomes to test the entire genome for linkage is proposed. The underlying principle is that each of the interchanged chromosomes in each stock would be marked by two widely separated breakpoints. Breeding procedures in maize for constructing a series with 2‐chromosome, double interchange stocks are described and illustrated by the results from a cross between two genetically marked T1‐5 interchange stocks. Breeding procedures for a series with 3‐chromosome, triple interchange stocks are described also.The detection of linkage with any major gene, using either the double or the triple interchange series should be much more efficient than tests using single interchanges. When heterozygous, many of the products of crossing over in the differential segments are deficient and hence not recoverable. Also only part of the recoverable crossovers are recognizable as recombinants.
Morphology and Inheritance of Sterile Brachytic Dwarfs in Peanuts, Arachis hypogaea1
Authors: Ashri A. 
Published: July 2010

Various morphological manifestations of brachytic dwarfs in peanuts, Anachis hypogaea L., and their inheritance have been studied. It was concluded that two duplicate genes control this trait, although a third locus was indicated in one cross. Apparently modifiers were also involved.These genes cause marked shortening of the internodes, petioles, flowers and floral organs and other deviations. The plants are male sterile, having no pollen. They are also female sterile, or are unable to support embryo development. The trait demonstrates how undesirable recessive alleles can accumulate in self‐pollinating amphiploid species, containing duplicate loci.
Flowering and Fertility of Alfalfa as Influenced by Inbreeding and Stage of Plant Growth1
Authors: Miller M. K. , Schonhorst M. H. 
Published: July 2010

Two clones of alfalfa (Medicago sativa L.) and their F1, S1, and S2 progenies were studied in the greenhouse at Tucson, Arizona. Numbers of seeds and pods produced and self‐fertility, measured as seed‐set percentage per self‐pollinated flower, generally decreased with inbreeding. The F1 plants sampled were more self‐fertile than either parent clone. No relationship was found between generations of inbreeding and number of racemes or flowers produced. Self‐fertility of all plants was highest during the first weeks of flowering; however, considerable variation occurred among plants in later weeks. The ratio of cross‐fertility (seed‐set percentage per cross‐pollinated flower) to self‐fertility of the parent clones was 4.1:1.0.Numbers of seeds and pods produced, and self‐fertillty were highly correlated. Numbers of racemes and flowers produced were also highly correlated, but they were not correlated with self‐fertility, number of pods, or number of seeds produced.
Nitrogen in Plant Parts of Seven Spring Wheat Varieties at Successive Stages of Development1
Authors: McNeal F. H. , Boatwright G. O. , Berg M. A. , Watson C. A. 
Published: July 2010

Nitrogen content of leaves and stems, head chaff, and grain was determined for seven spring wheat varieties on five sampling dates at two locations near Bozeman, Montana, in 1966. Nitrogen percentages in the chaff were at about the same levels as the nitrogen percentages in stems and leaves, and each decreased with successive sampling dates at nearly the same rate. Grain nitrogen percentages were similar at the late flowering and milk stages, but showed a significant increase by the dough stage.The amount of nitrogen translocated from top growth to grain averaged 66.2% under irrigation and 74.8% on dryland. Varietal differences in grain nitrogen percentages could not be attributed to differences in the percentage of total nitrogen that was translocated from top growth to the grain. Nitrogen increases in the total top growth from first to last sampling date were 85.1 kg/ha under irrigation and 20.1 kg/ha on dryland.Correlation coefficients at the irrigated and dryland locations of —0.88 and —0.93, respectively, for grain nitrogen percentages vs. the grain to straw ratio, and 0.89 and 0.92 for grain nitrogen content vs. total top yield indicate that grain nitrogen percentages are closely associated with top growth. These r values suggest that grain nitrogen percentages decrease as the grain to straw ratio becomes larger.
Influence of Intensity, Quality, and Duration of Light on Nitrogen Reduction and Assimilation in Wheat1
Authors: Harper James E. , Paulsen Gary M. 
Published: July 2010

'Pawnee' wheat (Triticutn aestivum L.) seedlings were grown under lighting of low (7,500 lux) or high (15,600 lux) intensities, blue (380‐470 mu) or red (680‐740 mu) qualities, and short (8‐hr) or long (16‐hr) nhotoperiods. A single level of N was supplied in graded ratios of nitrate and ammonium in solution cultures.In leaf blades, high light intensity had no consistent effect on nitrate reductase (NR) activity, increased soluble protein, and decreased nitrate. Blue light increased NR activity and soluble protein but decreased nitrate as compared with red light. The long photoperiod increased NR activity and decreased nitrate and soluble protein as compared with the short photoperiod. The light treatments had little effect on roots except for an accumulation of nitrate under the short photoperiod. NR activity and nitrate content in leaf blades and roots increased under all light treatments as the nitrate‐to‐ammonium ratio in the nutrient solution increased, and soluble protein content decreased slightly.
Inheritance of Pigment Color in the Soybean1
Authors: Bhatt G. M. , Torrie J. H. 
Published: July 2010

Fourteen soybean crosses, Glycine max (L.) Merr., were used to study the inheritance of pigment color and pattern. Black and brown seed coat and hilum colors were controlled by two gene pairs, Tt and Rr, their expression being modified in certain gene combinations by Oo and W1w1. The distribution or dilution of the pigment color was controlled by the locus (Ktiki). Brown seed coat (TrO) was dominant over reddish brown (Tro) and green seed coat (G) over yellow (g). The I allele for light hilum gave gray hilum with TR and tKW1 genotypes and yellow hilum with Tr, tRw1 and tr genotypes.Difficulty was experienced in classifying plants for saddle pattern, due to the possible interaction of pigment promoting factors. In three crosses the saddle pattern gene ik was dominant over self black seed, whereas in one cross self black seed appeared to be dominant over ik. Saddle patterns were not observed on seed having brown or buff seed coats. These phenomena may be due to pigment‐promoting factors masking the expression of the gene ik.
Phenotype Selection in Crested Wheatgrass1
Authors: Schaaf H. M. 
Published: July 2010

Open‐pollination progenies were used to study the effectiveness of phenotypic selection for seed characteristics in crested wheatgrass of Agropyron desertorum (Fisch. ex Link) Schult. maternal parentage. Source material consisted of 468 plants set out on 0.9‐m centers. The plants were assessed for spike number and seed yield, set, and size over a 2‐yr period (1959 and 1960). Progenies of the plants averaging in the top 10% of each of the four characters (125 “high” selections) and in the bottom 5% in spike number and seed size (19 “low” selections) were grown in rows seeded 0.9 m apart. Of the high selections 94, 26, and 5 were 1‐, 2‐, and 3‐character combinations, respectively.Seed yield of the progenies, averaged over a 3‐yr period (1962 to 1964), ranged from 147 to 687 kg/ha and seed size from 231 to 318 mg/100 seeds. Approximately 8% of the progenies significantly exceeded (P<.01) the crested wheatgrass variety ‘Nordan’ in both seed yield and size. Despite significant (P<.001) parent‐progeny correlations of .517 for seed yield and .797 for seed size, single‐character selection among spaced plants did not positively identify the most desirable genotypes for either yield or size of seed. Progeny seed yield averaged 416, 472, and 526 kg/ha and seed size 280, 275, and 290 mg/100 seeds for the 1‐, 2‐, and 3‐character combinations, respectively. Spaced‐plant selection for high spike number decreased progeny seed size and for low spike number increased progeny seed size. There were indications that multiple‐character selection of plants not in the top 10% would also have given high‐performing progenies. For screening source populations of crested wheatgrass for seed characteristics, large‐scale testing of open‐pollination progenies is suggested to reduce loss of valuable genotypes.
Heterosis and Hemeostasis in Secale montanum Guss. ✕ S. cereale L. Hybrids II. Reproductive Characteristics1
Authors: Pfahler P. L. 
Published: July 2010

F1 hybrids between Secale montanum (P.1.253956) the female parent and three varieties (‘Florida Black,’ ‘Gator,’ and ‘Wrens Abruzzi’) of S. cereale were made. F2 populations were produced by interpollination within each F1 population.Under natural daylength and space‐planted conditions, 40% of the S. montanum plants produced seed in 1965‐66 and 10% in 1966‐67, whereas 100% of the plants in the S. cereale varieties and 70 to 100% of the F1 and F2 plants produced seed. For number of seeds, seed weight, and grain yield, the F1 populations were generally intermediate to the parents with S. montanum the lower parent in all combinations. The F2 populations tended to produce a larger number of seeds than the corresponding F1. Substantial differences resulting from the S. cereale variety involved and year tested were observed. The variability of both the F1 and F2 populations as a result of differences in years and the variation within the F1 populations were greater than the higher parent. However, the S. cereale variety involved was a major factor.With 16‐hr daylength, the F1 populations were generally below or equal to the mid‐parent in percent stainable pollen with S. montanum the lower parent in all combinations. However, the corresponding F2 populations were higher in percent stainable pollen with two out of three combinations exceeding the S. cereale parent. The pollen diameter of the F1 and F2 populations was generally intermediate to the parents with S. montanum the lower parent in all combinations.
Triticale—A Review1
Authors: Briggle L. W. 
Published: July 2010

Triticale is a polyploid produced by doubling the chromosome number of the sterile hybrid that results from a cross between wheat, Triticum aestivum L. em Thell. (group aestivum) or T. turgidum L. (group durum) and rye, Secale cereale L.Hybrids between wheat and rye date back to 1875. The first amphiploid was reported in 1891. Early developed amphiploids involved hexaploid wheat with rye and had 56 somatic chromosomes.Recently there has been more interest in tetraploid wheat ✕ rye amphiploids which have 42 somatic chromosomes. Much effort has been expended toward development of high‐yielding Triticales as a field crop. Marked progress has been made in yield, kernel quality, meiotic stability, better plant type, and other characteristics. However, presently available Triticales cannot compete successfully with wheat in the U. S. Intensified breeding programs based on increased genetic variability in breeding material show promise for further improvement of Triticales.
Tillering and Coronal Root Formation in Some Common and Durum Wheat Varieties1
Authors: Pinthus Moshe J. 
Published: July 2010

Tillering and the production of coronal roots by the main shoots and individual tillers of early and late common (Triticum aestivum L.) and durum (Triticum durum Desf.) spring wheat varieties were studied under various environmental conditions.It was found that environmental as well as varietal effects on coronal root formation were mainly due to their effects on tillering.The results indicate that varietal differences in tillering and subsequent root production were induced by differences in the length of the period from seedling emergence to spike differentiation during which tiller primordia were formed and tillers developed. The highest rate of root formation occurred during the period from spike initiation to heading and therefore the length of this period also affected root production.Root production of the main shoot and the first one or two tillers terminated at heading time. Under favorable environmental conditions, early varieties were able to produce additional roots after heading, due to the renewed growth of late tillers and the development of new tillers from existing primordia.Durum wheat exceeded common wheat in the root production capacity of its main shoots. In both species only slight and inconsistent differences in the numbers of tillers and of roots were found among varieties with similar growing periods.
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.
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.
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 sugarsVariability 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.
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.
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.
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.