bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Intact Tillers and Height of Stubble on Growth Responses of Tall Fescue (Festuca arundinacea Schreb.)1
Authors: Matches Arthur G.
Published: July 2010

Complete defoliation of tall fescue (Festuca arundinacea Schreb.) seldom occurs under good grazing management. In this study, the influence of defoliation on the growth response of tall fescue plants was examined. Vegetatively propagated Kentucky 31 tall fescue plants, grown in the greenhouse, were cut back to a stubble height of 1, 21/2 or 4 inches in a factorial combination of leaving 0, 10%, 20%, or 30% intact (uncut) tillers. Increased tillering, greater daily and total regrowth yields of dry matter, and higher levels of food reserves resulted from increasing the height of stubble or from leaving intact tillers. Generally the influence of intact tillers, especially on rate of growth, decreased as the stubble height was increased. Plants completely defoliated to a 1‐inch stubble (1 inch‐0%) died within 32 days after the initial harvest, and there was a marked decrease in rate of recovery with each successive harvest of the 21/2 inches‐0% treatment. Within a stubble height, little change in tillering or regrowth yield resulted from leaving more than 10% intact tillers, but food reserves increased with each addition of intact tillers. Apparently 10% or more intact tillers or a 4‐inch stubble provide adequate photosynthate production and food reserve storage for plant survival and growth under conditions of defoliation stress.
Fourth Maturity Gene Locus in Sorghum1
Authors: Quinby J. R.
Published: July 2010

‘Hegari,’ a variety of Sorghum vulgare, Pers., has been identified for maturity as being Ma1Ma2Ma3ma4. A fourth maturity locus has, therefore, been recognized in sorghum. The dominant allele at the fourth locus occurs in the ‘Milo’ varieties in which the first three maturity gene loci were found.
Lodging Response of Certain Selections of Oats, Avena sativa L., and Their Hybrid Progenies1
Authors: Hess D. C. , Shands H. L.
Published: July 2010

Lodging responses of certain oat selections and their hybrid progenies were studied for three seasons at Madison, Wisconsin. Progeny rows were evaluated for lodging response by a “snap test” and by estimating actual lodging percentages. Analyses of variance indicated that lines were more accurately characterized by snap values than by lodging percentages. On the basis of intergenerational comparisons and genotype ✕ environment interactions, snap scores were more repeatable than were lodging percentages. Genotypic and phenotypic as well as simple correlations of snap scores with lodging percentages indicated that the snap test could be useful in evaluating oat lines for lodging responses.
Development of Photosynthesis in Cotton Seedlings, Gossypium hirsutum L.1
Authors: Richardson G. L.
Published: July 2010

An infrared gas analyzer was used to follow CO2 exchange (dark respiration and net photosynthesis) through the first 248 hr of germination of cotton seeds. The following events were noted: (a) dark respiration was first detectable 6 hr after placing the dry seed in water (planting); (b) the photosynthetic cempensation point was reached 86 hr after planting and 24 hr after emergence and occurred during the unfolding of the cotyledonary leaves; (c) maximum rates of net photosynthesis (33 mg CO2/dm2/hr at 64.8 kilolux with 500 ppm CO2) were attained by 200 hr after planting and remained at this level during the remainder of the test period (48 hr); and (d) photosynthetic rates increased as light and CO2 concentrations were increased. The fully expanded cotyledonary leaf stage (200 to 248 hr after planting) of the cotton seedling is suitable for photosynthetic studies cause of the stability and uniformity of the photosynthetic rate.

General Electric Cool Beam lamps were found to be equally as effective as sunlight in providing energy for fixation of CO2.

Dark respiration rates, determined throughout the experiment, increased from 0 to a maximum by 120 to 130 hr after planting and remained constant for the next 24 hr.
Inheritance of in vitro Digestibility and Associated Characteristics in Medicago sativa L.1
Authors: Gil Hernan Chaverra , Davis R. L. , Barnes R. F.
Published: July 2010

The progenies of 10 Medicago sativa L. clones were analyzed to determine the type of gene action conditioning in vitro dry matter digestibility (IVDMD) and related chemical components and the relationship to total digestible units (TDU) per unit area. The mean squares for both general and specific combining ability were significant for IVDMD. Usually, if the general combining ability effects for IVDMD of the clone were positive, the effects for yield were negative. The 10 crosses highest in sea effects for IVDMD had negative (low) specific combining ability effects for yield with one exception. Three of the 10 crosses with the highest specific combining ability effects for yield had positive sea effects for IVDMD. The other seven were negative.
Relationships Between Leaf Area Index and Apparent Photosynthesis in Alfalfa (Medicago sativa L.) and Ladino Clover (Trifolium repens L.)1
Authors: Wilfong R. T. , Brown R. H. , Blaser R. E.
Published: July 2010

Experiments were conducted to study the relationship between LAI, light penetration, and apparent photosynthesis in alfalfa and ladino clover stands intercepting between 80 and 100% of the incident sunlight. LAI‐light interception patterns for ladino clover and first growth alfalfa differed from those of second and third growths of alfalfa.

NAR decreased as LAI increased; the relation appeared to be curvilinear. This indicated that optimum LAI occurred over a broad rather than a narrow range. LAI‐apparent photosynthesis curves for alfalfa remained constant above the initial optimum LAI, although the curve for clover appeared to decline slightly beyond this point.

Initial optimiuni LAI coincided with the LAI's that intercepted approximately 95% of the incident light, indicating that Pa was near maximum at this point. LAI higher than required to intercept 95% of the light showed little effect on photosynthesis in the LAI range of 2 to 6. Dark respiration rates per unit of leaf area decreased as LAI increased. This may partially explain the leveling off of the LAI‐apparent photosynthesis curves at high LAI values.
Tassels and the Productivity of Maize1
Authors: Duncan William G. , Williams William A. , Loomis Robert S.
Published: July 2010

Shading of underlying leaves by maize tassels probably reduces photosynthetic rates in the community and hence the grain yields. The shading effect is small at low plant populations but increases with plant density. Tassel size varies with plant population and variety. The area of shade cast by a single tassel varies with sun angle. Possible effects of tassel shading on grain yield are estimated by computer simulation.
Relative Importance of Stem and Root in Determining Genotypic Differences in Sr‐89 and Ca‐45 Accumulation in Soybeans (Glycine max L.)1
Authors: Kleese R. A.
Published: July 2010

Stem grafts were made among 8 to 10‐day‐old soybean plants to ascertain the role of stem and root in determining varietal differences in accumulation of Sr‐89 and Ca‐45 in seed and in the terminal portion of the stem. The effect of the graft per se was negligible as evidenced by similar Sr‐89 and Ca‐45 accumulation in grafted plants with stem and root of identical genotype and the ungrafted plants of the same genotype. Accumulation of Sr‐89 and Ca‐45 in seeds was largely controlled by the genotype of the stem. In the terminal 12 to 15 cm of the stem Sr‐89 and Ca‐45 accumulation was controlled by both stem and root, with the stem being relatively more important
Allelic Tests among Ragged Leaf, Heritable Abnormalities 1, 2, and 3, Veins‐Fused, and Rugose Mutants in American Upland Cotton, Gossypium hirsutum L.1
Authors: Kohel R. J.
Published: July 2010

Six monogenic mutants that occurred spontaneously in Gossypium hirsutum were tested for allelism. Allelic tests were conducted among ragged leaf and Heritable Abnormalities l, 2, and 3 because of similar gene action. In all of these the mutant form is the heterozygote while the homozygote is semilethal. Veins‐fused and rugose were included because of phenotypic similarities to Heritable Abnormalities 1 and 3, respectively. Ragged leaf and Heritable Abnormality 2 were independent of each other and of the other mutants. Heritable Abnormalities 1 and 3, veins‐fused, and rugose were allelic and located at the crinkled‐dwarf (cr) locus. Heritable abnormality I and veins‐fused are phenotypically distinct from Heritable Abnormality 3 and rugose. This divergence of function is similar to that in the crinkled‐dwarf alleles of G. barbadense and suggests the existence of either a complex locus or two separate loci with tight linkage.
Spread of the Root System as Indicator for Evaluating Lodging Resistance of Wheat1
Authors: Pinthus Moshe J.
Published: July 2010

A technique for estimating the spreading angle of wheat roots is described and various methods of testing and sampling are discussed. The use of gravel beds with 3 or 4 replicates consisting of a single 1‐m row per variety or line and samples of 5 to 10 plants per row is recommended. High correlations were found between varietal means of spreading angles and lodging rates from a series of field trials grown under various environmental conditions. Spreading angle estimates may serve as a method of selecting for lodging resistance.
Relative Growth of Alfalfa and Birdsfoot Trefoil Seedlings under Low Light Intensity1
Authors: Cooper Clee S.
Published: July 2010

Growth of ‘Vernal’ alfalfa and ‘Tana’ birdsfoot trefoil seedlings at three ages was measured under four light intensities, 2153 to 8611 lux, in growth chambers. With decreasing light: intensity or seedling age, less of the dry matter accumulated during the growth period was partitioned into roots and more into stems. Relative growth rate of both species decreased similarly with decreasing light intensity due to decreased net assimilation rate. Leaf area ratio of both species increased with decreasing light intensity. With but one exception, RGR of birdsfoot trefoil seedlings of all ages was greater than that of alfalfa.
Changes in Reduction and Assimilation of Nitrogen During the Growth Cycle of Winter Wheat1
Authors: Harper James E. , Paulsen Gary M.
Published: July 2010

Changes in nitrate reductase activity and nitrate and water‐soluble protein contents of field‐grown ‘Pawnee’ wheat were studied throughout the growth cycle.

Crown tissue was analyzed during cold hardening and dehardening periods. Nitrate reductase activity was initially low, increased slightly during maximum hardening, and increased rapidly with dehardening. Water‐soluble protein and nitrate contents decreased with hardening and increased with dehardening.

During spring, aerial plant parts were analyzed separately. Nitrate reductase activity and water‐soluble protein contents were highest in the blades, with decreasing levels in sheaths, heads, and culms, respectively. Nitrate concentrations were highest in the culms, with less in sheaths, blades, and heads, respectively. Upper blades and sheaths contained greater nitrate reductase activity and water‐soluble protein, while nitrate concentrations were highest in lower blades and sheaths. All components measured decreased with maturity in all plant parts. Significant positive correlations were found between nitrate reductase activity and water‐soluble protein and between nitrate reductase activity and nitrate in crown, blade, and sheath tissues when these factors were compared within plant parts over sampling dates.
Estimates of General and Specific Combining Ability in F1 Hybrids for Grain Yield and Its Components in Grain Sorghum, Sorghum vulgare Pers.1
Authors: Beil G. M. , Atkins R. E.
Published: July 2010

The performance of 40 F1 hybrid populations of grain sorghum, obtained by crossing each of 5 male‐sterile lines to 8 pollen‐fertility restoring lines, was evaluated from tests conducted at 3 locations over a 2‐year period. Measurements for grain yield, number of heads per plant, weight of 100 seeds, and number of seeds per head were analyzed to obtain estimates of the relative magnitude of general and specific combining effects. Significant differences among general combining ability effects of the lines were obtained for all characters, while significant differences among specific combining ability effects were expressed only for 100‐seed weight. An evaluation of variance components revealed that the variances for general combining ability for grain yield were three times larger than the component for specific effects. A similar ratio for the two effects was obtained for both number of heads per plant and weight of 100 seeds. For number of seeds per head, the ratio of general to specific effects was markedly larger than the ratio observed for the other characters. Specific combining ability effects were usually more stable than general effects over the environments of this experiment, particularly for grain yield and seeds per head.

Correlations for the association of grain yield with its components disclosed that number of seeds per head was the component most highly related to yield, and that the expressions for yield were not affected appreciably by 100‐seed weight. While the ranges observed for number of heads per plant were relatively small in this experiment, significant negative associations for this trait with grain yield were observed for both the hybrids and parental lines.
Germination of Immature Kernels of Winter Wheat1
Authors: Robertson Larry D. , Curtis Byrd C.
Published: July 2010

Immature kernels of five winter wheat varieties were germinate as fresh and as air‐dried kernels at 7 C and 15 C in blotters and in soil. The kernels were collected at 3‐day intervals from 15 days after anthesis until the kernels were ripe, about 39 days after anthesis.

Air‐dried kernels (dried 3 days) germinate better than fresh kernels in the more immature stages. The 7 C temperature gave much higher germination than the 15 C temperature, particularly for air‐dried kernels.
Assimilation and Movement of Radioactive Carbon in Alfalfa and Reed Canarygrass1
Authors: Wolf D. D.
Published: July 2010

Alfalfa (Medicago sativa L.) and reed canarygrass (Phalaris arundinacea L.) were exposed in the field to radioactive carbon dioxide. Plants were treated at several maturity stages and C14 was measured in various plant parts at several dates following exposure. Carbon‐14 moved to the tap root during the 15‐min exposure time and accumulated with time in the tap root to a greater extent when exposed in the more mature stage (bud stage of alfalfa and early head stage of reed canarygrass) than when exposed in the vegetative stage.

Relative CO2 assimilation as influenced by several light intensities was measured by C14 in leaves after exposing plants to labeled carbon dioxide. Each reduction of light intensity resulted in reduced C14 in leaves. Light saturation (maximum C14O2 uptake) throughout the profile did not occur with 50% of full sun intensity. Measurable uptake of C14 occurred with 0.1% of full sun but may have been due in part to dark fixation.

Labeled carbon fed into one tiller of a plant as fructose and glucose was translocated throughout the underground rhizome system of a reed canarygrass clone and throughout all parts of an alfalfa plant. Carbon‐14 from fructose, the predominant building block of nonstructural carbohydrates in reed canarygrass, moved to a lesser degree than C14 from glucose. Carbon‐14 from glucose, the predominant building block of nonstructural carbohydrates in alfalfa, moved to a lesser degree than C14 from fructose.
Natural Outcrossing in Dwarf‐Internode Castor, Ricinus communis L.1
Authors: Brigham Raymond D.
Published: July 2010

Four groups of spineless (ss) dwarf‐internode castor plants derived from the variety ‘Baker 296’ were grown adjacent to or surrounded by normally spined (SS) plants, to determine frequency of natural outcrossing for the High Plains area of Texas. Wind velocity in this region ranges from 8 to 48 km (5 to 30 miles) per hour during the pollinating season. Progenies were classified as sparsely spined (Ss) as follows: ExperimenIt — single row of 20 ss plants, 42.2%; Experiment II — three adjacent rows of 20 ss plants at two locations, 46.3%; ExperimentIII — single ss plants interplanted with SS plants of various lines, 70.5%; and Experiment IV — single ss plants found in experimental plantings and commercial fields, 76.2%

Three of nine progenies in Experiment IV produced over 90% outcrossing, ranging from 54.1 to 100%. This group probably gave the best estimate of percentage outcrossing, as the ss plants were similar in flowering date, size, and genotype to the surrounding SS plants. Natural outcrossing of dwarf‐internode castor can well be in the range of 70–90% for the Texas High Plains.
Effect of Nitrogen Fertilization on the Amino Acid Composition and Distribution in Sorghum Grain1
Authors: Waggle D. H. , Deyoe C. W. , Smith F. W.
Published: July 2010

Effects of three levels of nitrogen fertilization and three locations were studied with three replications of each treatment to determine their relationships to the amino acid content and distribution in sorghum grain. Levels of 17 amino acids were determined in each sample. Protein and 17 amino acids were significantly increased by nitrogen fertilization. Distributions of the amino acids were significantly affected. Proportions of glutamic acid, proline, alanine, isoluecine leucine and phenylalanine were greater in protein of grain grown with highest nitrogen fertilization; proportions of lysine, histidine, arginine, threonine, and glycine were lower. Location significantly affected distribution of certain amino acids which may have been due to a different hybrid at one location or to difference in protein levels of grain grown at different locations, or to both.
Germination Response of Barley Following Different Harvesting Conditions and Storage Treatments1
Authors: Shands H. L. , Janisch D. C. , Dickson A. D.
Published: July 2010

The effects of harvest date and aerated and nonaerated damp storage over a period of time on the viability of three barley varieties were observed. The study included three storage moisture levels for one variety and two levels for another variety during a second year. Grain of different moisture contents was periodically sampled and germinated. Date of harvest influenced germination greatly, with later harvests showing successive reductions in germination. The samples from the first harvest showed a lower germination than those from the second harvest and were more subject to germination reduction at 18% storage moisture than more mature grain. The ‘Oderbrucker’ variety appeared to resist weathering better than ‘Traill’ or ‘X691‐1’. Grain at high storage moisture showed more damage when not aerated than when aerated.
Performance of a Winter Wheat Hybrid, F2, F3, and Parent Varieties at Five Population Levels1
Authors: Briggle L. W. , Petersen H. D. , Hayes R. M.
Published: July 2010

The F1 and parents involved in a winter wheat cross (‘Reed’ Χ ‘Gaines’) were grown at five population levels under irigation for 3 years at Aberdeen, Idaho. The F2 was grown in the same experiment for 2 years and the F3 for 1 year.

A slight amount of heterosis was expressed in plant height.

Heterosis was expressed by the hybrid in grain yield. When means over all five population levels were compared, the F1 produced more grain than either parent in all 3 years. Differences were significant except for that between the F1 and Gaines in 1965. The F1 produced significantly more grain than the F2 in 1964 and 1965, and the F3 in 1965. There was no significant difference between the F2 and F3 in 1965.

No heterosis was evident in number of spikes per plant. Gaines produced more spikes per plant than the hybrid each year. Some degree of heterosis was expressed in number of kernels per spike and in kernel size 2 years out of 3.

Reed (tall variety) was used as border around all plots in two replications and Gaines (short variety) was used as border in two replications in 1963 and 1964. The only significant competition effects measured were on height in 1964 and on grains of grain per plot in 1963. Each entry in 1965 was bordered by itself.

F1 and parent plants were slightly taller when grown at the higher plant densities.

Population level had an effect on grain yield. In 2 out of 3 years highest yields were produced by the hybrid and by Gaines at level 3. In no year were the F1 means at population levels 3, 4, or 5 significantly different. The same was true for both parents. On the basis of this test a producer could cut his seeding rate to that of population level 3 (approximately one plant per 2.5 cm (1 inch) or 0.9 hectoliter per hectare (3‐¼ pecks per acre). This could be important if hybrid wheat seed becomes available and is relatively costly. More tests at different population levels should be conducted before a general recommendation can be made.

Plants grown at low population levels produced more spikes and more kernels per spike than those grown at high levels. Seed size was little influenced by plant density, although there was a trend toward smaller seed at the high population levels.
Dormancy in Sorghum bicolor (L.) Moench I. Relationship to Seed Development1
Authors: Clark L. E. , Collier J. W. , Langston Ruble
Published: July 2010

Dormancy in relation to seed development in three varieties of sorghum (Sorghum blcolor (L.) Moench), ‘Martin’ (BTx398), ‘Combine Kafir‐60’ (BTx3197), ‘Feterita’ (RTx09), was investigated in 1963 at College Station, Texas. From the results of this investigation, three mechanisms were proposed to function in dormancy. The first mechanism was associated with initial seed moisture and functioned until seed moisture was reduced to approximately 28% or less. This mechanism apparently functioned in seeds of all the varieties investigated, and it was the only one of the three mechanisms that functioned in seeds of Feterita. The second mechanism was associated with active growth of the seeds and functioned until maximum dry weight of the seeds was attained. This mechanism functioned in seeds of Combine Kafir‐60 and Martin. The third mechanism functioned in seeds which had attained maximum dry weight and in which the moisture content was less than 28%. This mechanism was affected by the rate of seed development, and dormancy was more pronounced in seeds which developed more rapidly. The third mechanism functioned only in seeds of Martin. These mechanisms functioned only in intact seeds. Excised embryos from 15‐ through 30‐day old seeds were not dormant.
Development of Safflower Seed as Influenced by Windrowing, Varieties, and Season1
Authors: Urie A. L. , Leininger L. N. , Zimmer D. E.
Published: July 2010

Seed yield from windrowed safflower (Carthamus tinetorius L.) plants reached 95% and 100% maximum development 24 and 31 days, respectively, after 90% bloom in 1961. In 1962 only 77% maximum development was reached at 24 days and 88% at 31 days after 90% bloom. In 1962, moisture percentage at all windrowing dates was higher than in 1961. Weight per 100 seeds, oil percentage, and bushel weight in 1962 were lower at all windrowing dates than in 1961. When individual heads were sampled, maximum dry weight of seed was essentially reached at 28 days after flowering at 22 to 25% moisture in 1960 and 1961, and at 34 days after flowering at 31% moisture in 1962. Below normal temperatures during the growing season were primarily responsible for the slow rates of development and high moisture percentages in 1962, compared to the near normal years of 1960 and 1961. As found earlier and confirmed in 1962, N‐4051 reached maximum dry weight of seed approximately 1 week earlier than ‘US‐10’ or ‘Gila.’
Cytogenetic Studies on the Genus Linum1 II. Hybrids Among Taxa With Nine as the Haploid Chromosome Number
Authors: Gill K. S. , Yermanos D. M.
Published: July 2010

Cross‐compatibility, morphology, cytology and fertility were determined for six 18‐chromosome Linum taxa and nine of their “interspecific” hybrids. Meiosis in all parental materials was regular. In hybrids, meiosis was characterized by univalents and multiple chromosome associations at metaphase I. Chromosome pairing indicated that L. altaicum differs from L. alpinum, L. austriacum, L. julicum, L. narbonense, and L. perenne by one reciprocal translocation. L. austriacum and L. narbonense, and L. julicum and L. narbonense also apparently differ by one translocation, whereas L. perenne and L. narbonense appear to differ by two translocations. Chromosomes not involved in translocations formed normal bivalents indicating that they, in general, were homologous. Evolution of these taxa parallels speciation patterns through chromosomal reorganization.
Selection for Increased Lint Yield and Correlated Responses in Upland Cotton, Gossypium hirsutum L.1
Authors: Miller P. A. , Rawlings J. O.
Published: July 2010

Three cycles of recurrent selection for increased lint yield in Upland cotton (Gossypium hirsutum L) have been completed. Yield of the third cycle selections exceeded that of the base population by 29.7%. Response to selection was linear and is predicted to continue at approximately the same rate of gain for an additional cycle.

Correlated responses to selection for yield were observed for the majority of the unselected traits measured. As selection increased lint yield, simultaneous increases were observed for lint percentage, number of seed per boll, earliness, fiber elongation, and fiber coarseness. Boll size, seed size, and fiber length and strength decreased. Weight of lint per seed showed little change.

There was generally close agreement between predicted and observed responses to selection. This suggests that dominance effects were lacking or of relatively minor importance. Additive genetic effects would appear to predominate in this population, although additive ✕ additive effects cannot be excluded.
Selection History and Induced Polygenic Variability in Triticum Aestivum1
Authors: Goud J. V.
Published: July 2010

Incidence of polygenic mutations follows a trend opposite to the previous selection history of the variety. In N.P. 876, which is a low tillering variety, the incidence of polygenic mutations is in a positive direction; in N.P. 863 which is a high tillering variety the mean is shifted in the negative direction; whereas in N.P. 870 an average tillering variety there is no change in the mean. The variance is increased in all the varieties in treated populations.
Seed Pod Dehiscence in Lotus and Interspecific Hybridization Involving L. corniculatus L.1
Authors: Phillips R. L. , Keim W. F.
Published: July 2010

Whirty‐nine entries representing 16 Lotus species were tested for seed‐pod dehiscence at 38%, 33%, 25%, and 10.5% relative humidities. L. coimbrensis Willd. was the only species possessing completely indehiscent seed pods. L. angustissimus L. (Cyprus), L. tetragonolobus L., and two entries of L. ornithopodioides L. demonstrated a high degree of indehiscence.

In the 34 entries where all pods dehisced, the mean number uf days for seed.pod dehiscence decreased as the relative hmnidity decreased.

An interspecific‐hybridization study involving glabrous L. corniculatus (2n = 24) as the female parent and pubescent: L. coimbrensis (2n = 12) as the male parent was undertaken in an attempt to incorporate the indehiscent seed‐pod character of L. coimbrensis into the agronomically desirable L. corniculatus. The pollination of 2,498 flowers produced 13 putative hybrids exhibiting pubescence, a trait dominant in L. corniculatus. Also, pollen fertility was low in some of the hybrids. The somatic chromosome number of the putative hybrids was 24, general phenotypic appearance was similar to L. corniculatus except for the pubescence, and meiosis of the five offspring with the lowest pollen fertility was similar to that in L. corniculatus. Seed‐pod indehiscence was not observed. The four putative hybrids with the lowest pollen fertility were backcrossed to L. corniculatus. The presence of a high number of univalents in the backcross progenies supports the contention that interspecific hybridization was effected between L. corniculatus and L. coimbrensis.
Effect of Photoperiod and Temperature on Cold Hardening in Winter Wheat1
Authors: Paulsen Gary M.
Published: July 2010

Changes in hardiness and plant constituents associated with hardening were observed in ‘Pawnee’ winter wheat under constant and under decreasing photoperiod and temperature treatments. Hardening occurred only when the temperature decreased, and was greater under a constant long photoperiod than under a decreasing photoperiod. Least hardening occurred when the photoperiod was decreased and the temperature remained constantly high.

Changes in dry matter, reducing sugar, sucrose, and free amino acid contents of wheat crowns paralleled changes in hardiness. Soluble protein content of crowns was increased by decreasing photoperiod as well as by decreasing temperature.
Inheritance of Lint Quality Characteristics in Intraspecific Crosses Among Varieties of Gossypium hirsutum L. and of G. barbadense L.1
Authors: Marani A.
Published: July 2010

Lint quality was tested in six trials which were conducted from 1959 to 1965 in Israel. These trials included varieties of G. hirsutum L. and G. barbadense L. and the F1 intraspecific crosses within each species. F2's of these crosses were included in two of these trials.

A small effect of heterosis for upper‐half‐mean lint length was found in both species, with the magnitude of this heterosis larger in G. barbadense L. than in G. hirsutum L. The inheritance of this trait was found to be mostly additive, with small dominance effects in both species, and possibly also some epistatic effects in G. barbadense L. Results for mean lint length were similar.

Lint strength (Pressley tester, 1/8” gauge) of G. hirsutum L. Fl's was very close to mid‐parental performance, whereas G. barbadense L. F1's were much closer to the parent having stronger lint. Inheritance of this trait was found to be mostly additive, with some dominance effects in G. barbadense L. Fineness of lint (Micronaire) of intraspecific crosses of both species was found to be intermediate between parental performance, with a slight tendency of F1 fibers to be coarser. Large interactions of fineness with environment were observed.
Inheritance of Hydrocyanic Acid Production in Two Sorghum ✕ Sudangrass Crosses1
Authors: Barnett R. D. , Caviness C. E.
Published: July 2010

The inheritance of hydrocyanic acid (HCN) production was studied in populations derived from two sorghum ✕ sudangrass crosses. Plants from these crosses were sampled for HCN at two different stages of growth. Data from both crosses indicated that high HCN production was partially dominant to low HCN. The F2 distributions appeared to be unimodal and continuous. Broad‐sense heritabillty estimates ranged from 41.3 to 68.0. These values indicated that HCN production is a heritable character but may be influenced to a large extent by environment. Highly significant correlations were obtained for HCN levels of F2 plants when sampled at two stages of growth, although actual levels of HCN differed at the two growth stages.
Effect of Aphid Infestation on the Coumestrol Content of Alfalfa Varieties Differing in Aphid Resistance1
Authors: Loper G. M.
Published: July 2010

The effects of pea aphid and spotted alfalfa aphid infestations on the coumestrol content of three alfalfa (Medicago sativa L.) varieties and one alfalfa synthetic were determined in plant growth chambers. The alfalfas tested ranged from very susceptible to highly resistant to both aphid species. Coumestrol from aphid‐damaged tissue was identified by chromatography and ultraviolet spectroscopy. Aphid‐damaged portions of all varieties contained elevated coumestrol levels. Undamaged plant tissue and uninfested plants generally had less than 1 ppm coumestrol. The more resistant varieties accumulated less coumestrol than the susceptible variety ‘Vernal.’ Selection in alfalfa for aphid resistance can be expected to reduce the accumulation of coumestrol which results fiom aphid damage.
An Interaction Between Pollinators and Reciprocals in an Alfalfa Cross1
Authors: Pedersen M. W.
Published: July 2010

The extent of a reciprocal difference for seed and hay yield in a cross between two alfalfa clones was affected by the method of pollination. When compared to honey‐bee pollination leaf‐cutter bee pollination increased the difference by causing a higher yield of hay and seed with one clone as a female and a lower yield with the other clone as a female. Selfing on the more self‐fertile clone is considered of importance in the reciprocal effect. However, the more self‐fertile clone also has smaller seeds than the more self‐sterile clone. Apparently the efficiency of pollen transfer between different alfalfa plants is different for leaf‐cutter bees and honey bees.
An Association between Male Sterility and Fiber Strength in Hybrids of Upland Cotton, Gossypium hirsutum L.1
Authors: Meyer Vesta G.
Published: July 2010

Backcrosses of cytoplasmic‐genetic male sterility to Stoneville D2 247, an experimental strain of Upland cotton (Gossypium hirsutum) showed a highly significant correlation between fiber strength (T1) and male sterility. No such association between T1 and sterility appeared in similar backcrosses to several widely‐grown commercial varieties of Upland cotton.
Self‐Compatibility Studies with Diploid Alsike Clover, Trifolium hybridum L. III. Response to Temperature1
Authors: Townsend C. E.
Published: July 2010

The compatibility reactions of two diploid St alsike clover clones, 6–5 from the Danish variety ‘Otofte’ and 7–1 from an Ohio‐grown seed lot, were temperature‐sensitive in controlled environmental chambers. One to 2 days at constant 32 C changed the compatibility reaction of genotype 6–5 from self‐incompatibility to self‐compatibility. However, 2 to 3 days at 32 day‐27 C night temperatures were required to change the compatibility reaction of genotype 7–1. By the 4th day of treatment, 35 and 62% of the selfed florets were setting seed at the constant 32 C treatment for genotypes 6–5 and 7–1, respectively. Seed set for genotype 6–5 reached a high of 20% on the 5th day at the 32 day‐27 C night treatment; 11% of the florets set seed on the 4th day at the 32 day‐21 C night treatment; and a 4% seed set was reached on the 3rd day at the constant 27 C treatment. Genotype 7–1 did not respond to the 32 day‐21 C night and constant 27 C temperature treatments. After the compatibility reaction was changed at the high temperatures, propagules of the two genotypes were removed and placed at 21 C. The compatibility reaction of genotype 6–5 changed immediately to self.lncompatibility. However, 24 hr were required to change the compatibility reaction of genotype 7–1 from one of self‐compatibility to one of self‐incompatibility. The site of the change in the compatibility reaction for genotype 7–1 was the style, but it was not possible to locate the site for genotype 6–5.
Potassium in Mature Kernels of Normal and Opaque‐2 Maize1
Authors: Goodsell Samuel F.
Published: July 2010

In 63 paired comparisons, among progenies of Zeamays L., opaque‐2 kernels averaged 41% higher concentration and 27% more total K than translucent kernels Irom selfed or sib‐pollinated ears borne on F1 plants of inbred X opaque‐2 parents. Progenies averaging 11.0% protein were 0.37 and 0.52% K for translucent and opaque‐2 kernels, respectively. Progenies averaging 15.5% protein were 0.38 and 0.53% K for translucent and opaque‐2 kernels, respectively. The concentration of K was significantly higher for the opaque‐2 kernels from 38 samples of 16 inbred X opaque‐2 crosses and 25 samples of Illinois High Protein X opaque‐2 crosses. Data indicate that the high K concentration in opaque‐2 kernels may he controlled by the same gene system responsible for the opaque‐2 character.
Accumulation of Coumestrol in Barrel Medic (Medicago littoralis)1
Authors: Loper G. M.
Published: July 2010

Plants of barrel medic (Medicago littoralis Rhode) were grown in a soil‐manure‐peat mixture in a growth chamber under controlled environmental conditions to determine the effects of leaf maturation and physiogenic spotting ou accumulation of coumestrol. The plants were free of disease and insect pests. Under these conditions, a physiogenic leaf spotting occurred which increased with age of the plants. Coumestrol content of the leaves increased with spotting and age. Very high quantities of coumestrol (in excess of 2,000 ppm) were found in mature, heavily spotted leaves. The effects of leaf age and physiogenic spotting on coumestrol content could not be entirely separated. However, further work showed that coumestrol was concentrated in the spots. Mature leaves with no spots contained less than 10 ppm coumestrol. ‘Vernal’ alfalfa (M. sativa L.) was included in this study as a control. No coumestrol was detected in the leaves of Vernal in the vegetative or early flowering stages. Small amounts (less than 30 ppm) were found in yellowing leaves of Vernal in the green seedpod stage. No coumestrol was detected in the immature or mature reproductive tissues of either barrel medic or alfalfa.
A Proposed Standard Method for Illustrating Pedigrees of Small Grain Varieties1
Authors: Purdy Laurence H. , Loegering W. Q. , Konzak C. F. , Peterson C. J. , Allan R. E.
Published: July 2010

The proposed method of writing pedigrees of small grain varieties, a modification of the method proposed by G. A. Wiebe, is both simple and versatile. It can be used for either manual or automatic machine operations.
Root Elongation in the Preemergence Stage of Mediterranean Grasses and Legumes1
Authors: Tadmor Naphali H. , Cohen Yehezkel
Published: July 2010

Rooting depth of seedlings at emergence was determined by radioisotope tracing (P32) for six range plants: Agropyron desertorum (Fisch.) Schult; Avena sterilis L.; Medicago hispida Gaertn.; Oryzopsis holciiormis (M. B.) Hack.; Phalaris tuberosa L.; and Vicia dasycarpa Ten.; with wheat and barley as controls.

Seeds were planted from 2 to 18 cm deep in loess soil in a growth chamber at 20 C constant temperature. Except for the 2‐cm depth no interaction was found between root length and depth of planting. Seedling roots reached a certain length and no more before onset of photosynthesis. This length varied greatly with the species: 4 to 6 cm for the perennial grasses anl legumes; 6 to 8 cm for Avena; and 12 cm in wheat and barley. Root length was generally correlated with mean seed weight.

The depth seedling roots have reached by the time of emergence is a sum of depth of planting and root length. The deepest root penetration occurred at the greatest planting depth from which seedlings emerge. Shallow planting may be suboptimal under arid conditions, and the deepest planting form which emergence is still satisfactory seems to be optimal. Root elongation in the preemergence stage may therefore become a useful criterion in breeding species for arid range.
Genetic Studies in Spanish Clover, Desmodium sandwicense E. Mey. II. Isolation and Identification of Anthocyanins in Flower Petals1
Authors: Park Soon Jai , Rotar Peter P.
Published: July 2010

Anthocyanin pigments in petals of Spanish clover were isolated and identified in order to investigate their relationship to flower color inheritance. Only one kind of anthocyanin, malvidin 3,5‐diglucoside, was found in various color classes. Color variation resulted primarily from quantitative differences of the anthocyanin pigment concentration. Dark purple petals contained about nine times as much anthocyanin as near white forms. The relative concentration of the anthocyanin pigment between the colored and near white flowers was about 5:1. This difference in concentration appeared to be inherited under monogenic control. On two‐dimensional paper chromatograms, five major yellow spots of other flavonoid pigments were observed and they appeared to have secondary role, both qualitatively and quantitatively, in production of narrow color variation of flowers.
Reciprocal Crosses and Their Influence on Wheat Quality1
Authors: McNeal F. H. , Berg M. A. , Watson C. A.
Published: July 2010

Four crosses with their reciprocals and parents were evaluated for milling and baking quality and for agronomic characteristics in 1966 and 1967. The four parental varieties used in crosses represented a range in quality. Reciprocal crosses differed little in milling and baking quality, as indicated by significant differences in only 2 of 64 quality comparisons. Three of 28 agronomic comparisons differed significantly.

Quality values for crosses were mostly intermediate between the two parents, with some values approaching those of the best parent and some significantly lower than the best parent. No quality value of the crosses exceeded the best parent significantly.
Inheritance of a Seedling Marker in Tetraploid Crested Wheatgrass1
Authors: Dewey Douglas R.
Published: July 2010

The first documented genetic seedling marker in tetraploid crested wheatgrass, Agropyron desertorum (Fisch. ex Link) Schult., is described. The recessive marker, designated as “green seedling” and represented by the gene symbol “g”, is recognized by the absence of anthocyanin pigments in newly emerged seedlings. Expression of pigmentation in colored seedlings is apparently enhanced by light and favored by cool temperatures. Segregation in self and testcross progenies indicated that the character is controlled by a single tetrasomically inherited gene. Genetic stocks of each of the five possibe tetrasomic genotypes were isolated. Although chromosome segregation was assumed throughout, some chromatic! segregation occurred as evidenced by several cases of “double reduction”. The value of this seedling marker to crested wheatgrass breeders and geneticists was discussed, and several examples of its use were cited.
Temperature and the Flowering Intensity of Ladino Clover Stolons1
Authors: Ridley Jack R. , Laude Horton M.
Published: July 2010

Clones of Ladino clover were grown in the greenhouse and in growth chambers to investigate the effect of temperature on flowering. Temperatures of 15, 21, or 32 C were used during photoperiodic induction. Flowering intensity was positively associated with induction temperatures. The higher temperatures increased whereas the lower decreased flowering. Temperature during the latter portion of the daily light exposure and the dark portion of the long‐day cycles was found to be most critical. Air temperature at the stolon apex affected flowering more than did temperature at the expanded leaves.
Extent of Intermating in Self‐Pollinated Species Necessary to Counteract the Effects of Genetic Drift1
Authors: Baker R. J.
Published: July 2010

Monte Carlo simulation of a two locus model in self‐pollinated species led to the conclusion that mating of as few as 20 or 30 pairs of randomly chosen F2 individuals would approximate true random mating to the extent that genetic drift would not negate the effects of random mating. Subsequent simulation of a nine locus model led to similar conclusions on a more general basis. Results of the latter work suggested that recurrent selection would have to be used to take full advantage of the increase in selection potential attributable to random mating.
Aneuploids in Seedling Populations of Tetraploid Alfalfa, Medicago sativa L.1
Authors: Bingham E. T.
Published: July 2010

Frequencies of aneuploids in ‘Vernal’ and ‘Saranac’ alfalfa were 6% and 3%, respectively, at the time of seed germination. Aneuploids had 31 or 33 chromosomes, with only two exceptions. The effect of observed aneuploid frequencies on genetic ratios and estimates of double reduction was determined. These values would be only slightly affected if the aneuploidy were distributed over all eight sets of homologous chromosomes, but an erroneous double reduction estimate of 2‐5% would be obtained if one homologous set were preferentially involved. No somatic instability, accessory chromosomes, or fragments were observed in 209 plants examined.
Chromosome Associations in Triploid, Tetraploid, and Pentaploid Hybrids of Avena magna (2n=28)1
Authors: Sadanaga K. , Zillinsky F. J. , Murphy H. C. , Smith R. T.
Published: July 2010

Diploid Avena strigosa Schreb. and A. wiestii Steud., tetraploid A. abyssinica Hochst., and hexaploid A. sativa L. and A. sterilis L. were cross‐compatible with A. magna Murphy and Tcrrell All hybrids except the pentaploids were sterile. Partial homology of the A genome of the diploid species with one genome of A, magna was indicated by the chromosome associations observed in the triploid hybrids A. magna ✕ A. wiestii and A. strigosa ✕ A. magna. In the tetraploid hybrid, A. abyssinica ✕ A. magna, chromosome associations suggest that the two species have one or both genomes partially common. In the pentaploid hybrids, the frequencies and kinds of chromosome associations observed suggest that A. magna may have two genomes partially in common with two genomes of the hexaploid species, a common genome and the remaining genomes partially common, or two genomes partially in common with the three genomes of the hexaploids.
Yield Component Heritabilities and Interrelationships in Winter Wheat (Triticum aestivum L.)1
Authors: Fonseca Santiago , Patterson Fred L.
Published: July 2010

A seven‐parent diallel cross of winter wheat was grown in the F1 generation in hills for 2 years and in the F2 generation in hills and in nursery yield plots the second year. Heritability estimates for earliness of flowering, height, number of spikes, kernels per spike, kernel weight, and grain yield were obtained from regression of F1 or F2 means on mid‐parent values. Simple correlations were calculated among all variables. The correlations were analyzed further by the path coefficient technique to determine direct and indirect effects.

Heritability estimates from data from hills for earliness, height, number of spikes, and kernels per head were high and those for kernel weight and grain yield were intermediate or low. Estimates in the F1 and F2 generations from data obtained from hill plots were reasonably similar. Estimates of heritabilities for the six characters from the F2 generation, were very similar for hills and thick‐seeded nurseries.

The three components of yield were highly correlated with grain yield. The path‐coefficient analysis indicated that each of the components had large direct effects on grain yield but important indirect effects resulting from negative correlations among yield components.
Mutation Induction in Melilotus Alba Annua by Chemical Mutagens1
Authors: Kleinhofs A. , Gorz H. J. , Haskins F. A.
Published: July 2010

Hydroxylamine (HA), 2‐aminopurine (AP), 5‐bromouracil (BU), and ethyl methanesulfonate (EMS) were tested for mutagenic activity on seeds of Melilotus alba annua. Mutants were classified into the following categories: o‐hydroxycinnamic acid (o‐HCA) content and β‐glucosidase activity, chlorophyll deficiency, dwarf growth habit, and miscellaneous morphological variations. Due to difficulties in classification, the o‐HCA and β‐glucosidase category and the dwarf category were unreliable for determining mutation rates. Based on the chlorophyll‐deficient and miscellaneous morphological categories, mutation rates for HA, AP, and BU treatments did not differ from the control rates, but EMS at 0.003M and 0.004M concentrations was highly effective in inducing mutations in these categories. Mutation rates based on chlorophyll deficiency were somewhat higher and more sensitive to EMS concentration than were mutation rates based on the miscellaneous category. Large numbers of chlorophyll, dwarf, and morphological variants, several more vigorous than the controls, were isolated from the EMS treatments, but no new o‐HCA or β‐glucosidase mutants were obtained.
Safflower Introductions Resistant to Fusarium Wilt1
Authors: Knowles P. F. , Klisiewicz John M. , Hill A. B.
Published: July 2010

Seed samples of several introductions of safflower (Carthamus tinctorius), found to be resistant to wilt caused by Fusarium oxysporum f. carthami, are available under Genetic Stock numbers.