bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Diplodia Stalk Rot on Stalk Quality in Corn (Zea mays L.)1
Authors: Loesch P. J. , Zuber M. S. , Calvert O. H. , Hilderbrand E. S. 
Published: July 2010

Four single crosses in corn (Zea mays L.), representing a wide range in stalk‐lodging resistance, were evaluated for reaction to Diploidia maydis (Berk.) in Experiment I. Crushing strength and rind‐thickness values were higher in the lodgingresistant and intermediate single crosses than in the two lodgingsusceptible crosses. Increased stalk rotting, resulting from inoculation with D. maydis, greatly affected crushing strength and stalk rot ratings but had no significant effect on rind thickness. Reductions in crushing strength due to D. maydis were substantially greater for two lodging‐susceptible single crosses than for an intermediate or a resistant one. The two lodging‐susceptible single crosses were also susceptible to D. maydis.In Experiment II the crushing strength, weight of 5.1‐cm stalk section, and rind thickness were reduced and stalk‐rot ratings increased as plant‐population densities were increased. Crushing strength of the lodging‐resistant single cross was weakened nearly as much as a lodging‐susceptible single cross by D. maydis. Stalk‐rot intensity was negatively correlated with crushing strength. Weight of section and rind thickness were positively correlated with stalk crushing strength. Stalk rot (as a component of crushing strength) was relatively independent of rind thickness and stalk weight. Data from these experiments show that Diplodia is an important variable contributing to stalk quality and has an effect in reducing crushing strength but is relatively independent of rind thickness and weight of stalk section.
Comparisons of Corn (Zea mays L.) Inbreds and Hybrids Grown at Equal Leaf Area Index, Light Penetration, and Population1
Authors: Johnson D. R. , Tanner J. W. 
Published: July 2010

Previous yield comparisons between inbred lines and hybrids in corn (Zea mays L.) were generally based upon a common plant density. Hybrids may exhibit a competitive advantage over the inbreds due to their superior size and leaf area. In this study the size differences were eliminated by growing a commercial double‐cross corn hybrid, the two parental single crosses, and their inbred parents at populations that resulted in a common population, a common LAI, and a common percent light penetration value.At the same plant population the single crosses were superior to their respective inbred parents in: (i) vegetative yield; (ii) grain yield; (iii) rate of grain dry ter accumulation; (iv) length of the grain‐filling period; (v) number of kernels per hectare; and (vi) final kernel weigbt.At equal LAI and percent light penetration the inbreds equaled their respective single cross progenies in total vegetative yield and number of kernels per hectare. The hybrids were superior to their inbred parents for the other components studied.The percentage of soluble solids in the stalks was greater in the inbreds, which may have been an effect of the slower rate of grain filling.
Grain and Plant Nitrogen Relationships in Eight Spring Wheat Crosses, Triticum aestivum L.1
Authors: McNeal F. H. , Berg M. A. , McGuire C. F. , Stewart V. R. , Baldridge D. E. 
Published: July 2010

Samples of high and low grain protein content (%) were compared from each of eight spring wheat crosses. The high protein samples were obtained by compositing 14 F3 progeny rows from the high end of the F3 distribution curve; the low protein samples were obtained similarly from the low end of the F3 distribution curve. These composites were seeded at three Montana locations and evaluated for agronomicharacteristics and for grain and plant nitrogen to help determine the nature of the expression of grain nitrogen content in spring wheat.Grain nitrogen content was negatively related to grain yield and to the graln‐straw ratio. High and low protein composites at Bozeman produced the same amount of above ground plant nitrogen, and each translocated the same percent of nitrogen to grain. However, grain nitrogen content of the high protein composite was significantly higher because of the distribution of a similar amount of nitrogen to a smaller amount of grain.Differences in plant growth characteristics among the eight crosses seem to account for the differences in grain nitrogen content.
Combining Ability Among Four‐Clone Alfalfa Synthetics1
Authors: Hill R. R. , Leath K. T. , Zeiders K. E. 
Published: July 2010

Two groups of experimental alfalfa (Medicago sativa L.) synthetics were produced, 36 synthetics from 10 related parents in one group and 24 synthetics from nine unrelated parents in the other. Combining ability variances were estimated for spring growth, yield, recovery after the first harvest, fall growth, stand, and frost damage in a field experiment, and for reaction to seven pathogens in greenhouse experiments.Significant general combining ability variance was detected for spring growth, yield, recovery after the first harvest, and for reaction to Colletotrichum trifolii Bain and to Pseudopeziza medicaginis (Lib.) Sacc. in both groups of synthetics. General combining ability variance for stand, and reaction to Phoma herbarum West f. medicaginis West ex. Rab., Uromyces striatus Schroet. var. medicaginis (Pass.) Arth., and to Corynebacterium insidiosum (McCull.) Jens, were significant in one or the other of the two groups. Significant specific combining ability variance was observed for yield, stand, frost damage, and reaction to C. trifolii, U. striatus, and C. insidiosum in one or the other of the groups. Significant combining ability variances were not detected for reaction to Stemphylium botryosum Wallr. and Leptosphaerulina briosiana (Poll.) Graham and Luttrell in either group of synthetics. We concluded that specific combining ability variations in the four‐clone alfalfa synthetics in both groups were so small that breeding procedures that operate on additive gene action would be more effective in development of improved synthetics than attempting to utilize specific combining ability effects by screening numerous experimental synthetics.
Cytoplasm Effects in Relation to Agronomic Performance of Grain Sorghums, Sorghums bicolor (L.) Moench1
Authors: Atkins R. E. , Kern J. J. 
Published: July 2010

Grain sorghums (Sorghum bicolor L. Moench) differing in cytoplasmic and genetic factors affecting pollen.sterility were compared during 2 years in Iowa. Six hydrids with normal cytoplasm did not differ significantly from their counterparts in male‐sterility‐induclng cytoplasm for grain yield or the primary components of yield. In 1968 the normal‐cytoplasm hybrids bloomed later (1 day), were shorter (3 cm), and produced greater area of the third leaf from the top (9 cm2) than did the hybrids with sterility‐inducing cytoplasm. In 1967 the two types did not differ significantly for these characters, and the differences do not seem of practical importance in either year.Crude protein content of the seed and pollen‐sterilty were significantly greater in both years for the sterile‐cytoplasm hybrids. Type of cytoplasm had little effect on the content of protein amino acids in the seed. Fertility‐restoration alleles seemed only to affect pollenfertility, and showed little influence on other characters.
Inheritance and Physiological Effects of Stomatal Frequency in Barley1
Authors: Miskin Koy E. , Rasmusson Donald C. , Moss Dale N. 
Published: July 2010

We studied inheritance of Stomatal frequency in five barley (Hordeum vulgare L.), populations and the effect of Stomatal frequency on photosynthesis, transpiration, and Stomatal resistance to diffusion. The latter studies were done using barley lines high and low in Stomatal frequency from two backcross populations.Heritabilities, estimated by the parent‐progeny regression method, ranged from 22 to 74%. These estimates were for the F2 and F3 generations on the individual plant basis. Realized heritabilities based on simulated high and low selection were in good agreement with the regression estimates, although the estimates were consistently higher for the high than for the low selection.For plants pretreated to assure open stomata, Stomatal diffusive resistances and transpiration rates differed statistically among lines, but photosynthesis did not. Lines having low Stomatal frequencies had higher Stomatal resistances, and transpired less water than lines with more stomata. A 25% decrease in frequency of stomata reduced transpiration rates by about 24%. Stomatal frequency did not influence the rate of photosynthesis, however. Hence, the possibility exists of altering transpiration without altering photosynthesis by selecting varieties with fewer stomata.
Association Between Chemical Composition of Seed and Seed Yield of Soybeans1
Authors: Hartwig Edgar E. , Hinson Kuell 
Published: July 2010

Soybean [Glycine max (L.) Merrill] lines selected for differences in oil percentage from BC1 and BC2 populations were evaluated for seed yield, oil percentage, and protein percentage. Selection on the basis of oil percentage was effective in obtaining lines distinctly different in protein percentage.High‐protein lines averaged lower yields than did high‐oil lines. All BC1 lines averaged lower in seed yield than BC2 lines. Evidence is presented to show that factors other than chemical composition have influenced the seed yield level of the lines selected.
Heterosis During the Early Phases of Growth in Intraspecific and Interspecific Crosses of Cotton1
Authors: Marani A. , Avieli E. 
Published: July 2010

The performance of interspecific and intraspecific F1 hybrids of Gossypium hirsutum and G. barbadense planted on two different dates was investigated. The interspecific crosses showed significant heterosis for percentage and time of germination, leaf number, and date of square formation when planted on the first planting date, and for plant height, LAI, and dry matter weight for both planting dates. The G. barbadense intraspecific cross exhibited a higher degree of heterosis than the G. hirsutum one for germination and dry matter weight when planted on the first planting date.The traits exhibiting significant estimates of heterosis for early planting, but not for late planting, were those associated with the early phases of plant growth. The differences stemming from planting dates were probably due to the low temperature that prevailed after the first planting, since the temperature after the second planting was close to the optimum. We concluded that F1 hybrids have greater phenotypic stability than their parents when confronted with varying temperature conditions. This condition probably results from their heterosis for seedling growth rate under suboptimal temperature regimes.
Deposition, Retention, and Translocation of 2,3,5‐Triiodobenzoic Acid Applied to Soybeans1
Authors: Ohki Kenneth , McBride Landy J. 
Published: July 2010

Factors related to TIBA (2,3,5‐triiodobenzoic acid) deposition and retention on soybean [Glycine max (L.) Merrill] leaves and TIBA translocation were studied with 125I‐ and 131I‐ labeled TIBA. Factors studied were four TIBA salt forms and four surfactants at two concentrations of each surfactant.Mean values for salt forms indicated no salt effect on TIBA deposition. Surfactant type had a pronounced effect on TIBA deposition. Maximum and minimum depositions were attained with Tween‐20 and Triton X‐100, respectively. Both surfactants were nonionic, indicating nonspecificity in relation to ionogenic types of surfactant. The higher surfactant rate varied from no influence to a depressive effect on TIBA deposition, indicating nonspecificity in TIBA‐surfactant concentration relationships.TIBA retention was enhanced at the higher surfactant rate by the two nonionic surfactants, while no effect was attained by the higher rate of the cationic and anionic surfactants. TIBA was rapidly translocated from recently matured leaves to young developing leaves and tissues of high metabolic activity.
Inheritance and Distribution of Grass‐Dwarfing Genes in Short‐Statured Wheats1
Authors: Fick G. N. , Qualset C. O. 
Published: July 2010

The inheritance of the grass‐dwarf phenotype was studied in three crosses of wheat (Triticum aestivum L.) involving the varieties ‘Ramona 50,’ ‘Nainari 60,’ and ‘Olesen’ crossed with grass‐dwarf ‘UCD 6914.’ F1 and F2 data indicated that grass‐dwarfing genes D1 and D2 in the Ramona 50 and Nainari 60 crosses and D1, D2, and D3 in the Olesen cross interact to produce grass‐dwarf plants. Limited evidence suggested that grass‐dwarfing genes also influence height of plants of a normal phenotype.UCD 6914 and ‘Cheyenne’ were two of several varieties found to be useful as tester genotypes for detecting the presence of grass‐dwarfing genes among varieties of unknown genotype. Eleven of 20 short‐statured selections from several countries were identified as carrying genes which condition the grass‐dwarf phenotype. The possibiliity that semi‐dwarf varieties may have been derived from variants of the grass‐dwarf type is suggested.
Genetic Variability in Floral Characteristics Influencing Outcrossing in Oryza sativa L.1
Authors: Virmani S. S. , Athwal D. S. 
Published: July 2010

The genetic variability and correlation coefficients involving five floral characters were investigated in a group of 29 cultivated and wild rices (Oryza Sp.). Wide variability existed in anther length, stigma length, and percent exserted stigma. The genetic variation constituted a high proportion of the total variation for these traits. Thus, selection for these characters is expected to be highly effective. The percent exserted stigma showed a high positive correlation with stigma length. Both traits also were correlated positively with spikelet length and anther length.One accession each of Oryza saliva f. spontanea and O. perennis subsp. balunga possessed anthers twice as long as those of cultivars. They also had a much higher proportion of exserted stigmas than most cultivated varieties.
Induced Seed Dormancy in Weeping Lovegrass, Eragrostis curvula1
Authors: Voigt P. W. 
Published: July 2010

Induction of dormancy in seeds of weeping lovegrass, Eragrostis curvula (Schrad.) Nees, by cool temperatures imposed during imbibition was first observed during germination trials of several warm‐season grasses. The purpose of the work reported here was to define the conditions necessary for the induction of this dormancy. Variables studied included: temperature during imbibition, length of temperature treatment, light conditions during treatment and evaluation, and age of seed. An experiment was also conducted to determine if dormancy could be induced in seeds planted in soil. Studies were conducted in growth chambers and greenhouses using several lots of ‘Morpa’ weeping lovegrass.Dormancy was not induced in a 3‐year‐old seed lot; it was induced only in darkness in a 2‐year‐old seed lot and was induced in darkness, and to a lesser extent in light, in a 1‐year‐old seed lot. Dormancy was not induced at an alternating temperature of (minimum/maximum) 2/7 C within 35 days. It was induced with 21 days at 7/13 C; with 14 days at 13/18 C; and with 7 days at 18/24 C. Germination was normal at 24/29 C. Dormancy was induced in seed planted in soil.Temperature‐induced dormancy appears to be a mechanism that can maintain and extend seed dormancy in weeping lovegrass. It is at least partly responsible for dormancy induced in nondormant lovegrass seeds planted in cool soil.
Yield Adjustment for Missing Units in Spring Wheat1
Authors: Busch Robert H. , Ergun Yusuf 
Published: July 2010

Plot rows of spring wheat (Triticum aestivum L.) having missing areas were studied to determine if an appropriate correction factor could be determined to adjust plot yields. Areas ranging from 0 to 240 cm (0 to 8 missing units or 50% of the area) were removed in one or two plot rows harvested subsequently for yield. Different genotypes, with diverse agronomic characteristics, were included in different years.Generally, no significant decrease in yield of the genotypes was detected until more than 60 cm (12.5%) of plot area was removed. Regression analyses were performed each year and indicated that the average slope (b) based on percent reduction in yield per missing unit (30 cm) was about 4.55%. The b values ranged from 3.7 to 5.0% reduction in yield per missing unit across genotypes and years. Satisfactory adjustments of yield, based on the average percent reduction (4.55%), were obtained if yield adjustment was ignored until more than 2 missing units (60 cm) occurred.
Factors Influencing Vegetative Growth and Flowering in Astragalus cicer L.1
Authors: Townsend C. E. , McGinnies W. J. 
Published: July 2010

Cicer milkvetch (Astragalus cicer L.) grows and flowers poorly in the greenhouse during the winter. These characteristics retard progress in a plant improvement program. Therefore, the influence of environmental conditions on vegetative growth and flowering of 36 clones of cicer milkvetch was studied in growth chambers, greenhouse, and field. The four growth‐chamber environments were 27 C day‐21 C night, 27 C day‐16 C and 21 C night (4.5 hours at each temperature), 27 C day.21 C night with a low‐temperature pretreatment, and 32 C day‐21 C night with a low‐temperature pretreatment. The low‐temperature pretreatment consisted of placing the clones in the dark for 3 weeks, with 1 week each at 5, 1.5, and ‐2 C. Day length in the growth chambers and greenhouses was 15 hours.There were significant differences among treatments and clones for number of tillers, length of tallest tiller, total dry weight, days to flower, number of racemes, and number of florets. Preconditioning with low temperatures increased number of tillers per plant. Mean plant height was greater in the growth‐chamber treatments than in the field or greenhouse, but dry‐weight production was highest in the field. The leaf component of total dry weight was higher than the stem component in all environments.More florets were produced at the 27 C day‐21 C night environment with pretreatment at relatively cool temperatures than at the other growth chamber treatments. Some clones did not require exposure to low temperature for flower induction. Twenty‐one clones flowered in the field the first season, but after going through the winter, all 36 clones flowered the second season. Several clones required exposure to lower temperatures and perhaps for a longer period than those in our low‐temperature environment before flowering was induced.
Cyclic Flowering Patterns in Flax as Influenced by Environment and Plant Growth Regulators1
Authors: Hovland Aurora S. , Dybing C. Dean 
Published: July 2010

Studies were conducted to determine the mechanism which regulates flowering pattern in flax (Linum usitatissimum L.). CI 1303 flax produced flowers in cycles with distinct blossoming periods separated by brief rest periods (20 days) when grown in the field or in green. house and growth chamber environments in nutrient solution. Removal of bolls at the end of the first flowering period caused prompt renewal of flower production. Daily flower removal resulted in continuous flowering without rest periods and without plant senescence. An increase in light intensity from 14,300 to 25,500 lux increased seed production in the first flowering period, but further increase to 31,900 lux produced no additional increase in yield. Enhancement of CO2 level to 1270 ppm increased flower, boll, and seed production in the first flowering peirod. The plants flowered in cycles in spite of high light and CO2 levels.Buds excised from the panicle and main‐stem and cultured in vitro produced shoots and then, in 4 to 30 days, produced flowers. Blossoms were produced even by buds which are normally inhibited in the intact plant. Maximum flower counts were obtained from buds isolated at the beginning of a flowering period. Auxins and gibberellin added to the medium at 5 or I0 ppm levels inhibited flower development. It is concluded that cyclic flowering is causally regulated by hormonal systems, but the number of flowers produced in each flowering period is limited by nutritional factors and rate of plant senescence.
Correlations Between Kernel Plumpness, Lodging, and Other Agronomic Characteristics in Six‐Rowed Barley Crosses1
Authors: Nasr H. G. , Shands H. L. , Forsberg R. A. 
Published: July 2010

Phenotypic (rP) and genotypic (rG) correlation coefficients between pairs of several important agronomic characteristics, including kernel plumpness, test weight, lodging resistance, and grain yield, were calculated for 19 populations of seven six‐rowed barley (Hordeum vulgare L.) crosses. Parents used were wide‐kerneled ‘Larker’ and ‘X969‐3,’ medium‐kerneled ‘Dickson’ and ‘X1068.1,’ and thin‐kerneled ‘Fraeg’ and ‘J2458‐1.’ The latter two are short and comparatively stiff‐strawed.Of 72 significant rP values obtained, 48 values occurred among the six possible character pairs between the four traits listed above. All 48 represented agronomically desirable associations and were equally divided between generations of single and backcrosses. Thus, selection for any one of these desirable characters would be compatible with concurrent selection for the other three. The rG value equalled or exceeded the rP value for 59 of the 72 significant rP values, strengthening the genetic or breeding implications.The strongest association among six plant and grain characters was between kernel plumpness and test weight. There was a definite trend for taller plants to perform better agronomically.
Changes in Carbohydrate Contents of Germinating Soybean Seeds1
Authors: Hsu S. H. , Hadley H. H. , Hymowitz T. 
Published: July 2010

Changes in dry weights, total soluble carbohydrates, and individual sugars in the cotyledons and embryo axes of soybean (Glycine max (L.) Merrill) seeds from a relatively high oil variety, ‘Hawkeye’ (22%), and a low oil line, P.I. 86002 (16%), were determined over a 13‐day germination period. Total dry weights of cotyledons decreased while those of embryo axes increased as the seed germinated. Total soluble carbohydrates accounted for 15% of the total dry weights in cotyledons of ungerminated seeds and decreased more rapidly throughout the germination period than did cotyledon weights. Total soluble carbohydrates of the embryo axes increased steadily during the first 5 days and declined thereafter. Similar patterns of utilization of soluble carbohydrates were observed for Hawkeye and P.I. 86002 even though their cotyledons differed 6% in oil content.Stachyose, raffinose, and particularly sucrose were the dominant sugars found in ungerminated soybean seeds. Stachyose and raffinose declined rapidly in the cotyledons by day 3 and disappeared by day 9 of germination. Sucrose increased slightly during the first 3 days but decreased steadily after the third day. Fructose and glucose appeared in day‐1 cotyledons, with the former reaching a maximum value on the fifth day and the latter on the ninth. Stachyose, raffinose, and sucrose were also the major sugars found in the 0‐day embryo axes. Stachyose and raffinose were depleted completely by day 3 in the embryo axes of P.I. 86002 and by day 5 in Hawkeye. Sucrose decreased between day 5 and day 13 for P.I. 86002 but showed irregular change in Hawkeye during this period. Fructose and glucose appeared in day‐1 embryo axes, continued to increase through day‐5 of germination, and decreased thereafter.