bluuebunny/crossref_metadata_2025 huggingface dataset:
Shrunken Endosperm Mutants in Barley1
Authors: Jarvi A. J. , Eslick R. F.
Published: July 2010

Six spontaneous shrunken endosperm mutants in barley (Hordeum vulgare L.) were identified and described. Five of the mutants (se1 through se5) were inherited as maternal plant monofactorial recessives and one mutant se6 was inherited as a monofactorial recessive expressing xenia. The mutants varied in fertility, seed weight, and seive size assortment. Four mutants were located on chromosome one, one on chromosome three, and one on chromosome six, by using translocation breakpoints as markers. Mutants similar to se1 through se5 could be used as males in commerical hybrid seed production. Mutants similar to se6 could be used as preflowering selective genes for the female stock for hybrid seed production.
Plant Regeneration from Tissue Cultures of Maize1
Authors: Green C. E. , Phillips R. L.
Published: July 2010

Effective utilization of cell and tissue culture methods in Zea mays research requires cultures capable of plant regeneration. These differentiated plants would provide a direct link with conventional genetic and breeding procedures.

Maize callus from embryo scutellar tissues was initiated and maintained on MS medium inorganic components, Straus medium vitamins and amino acids, 20 g sucrose and 8 g agar per liter, and 2 mg 2,4‐dichlorophenoxyacetic acid (2,4‐D)/liter. Callus has been maintained subculture every 21 to 28 days and has remained capable of differentiation for 9 months. Regeneration of complete plants was accomplished by subculture of callus to 0.25 mg 2,4‐D/liter for 30 days followed by transfer to 2,4‐D‐free culture medium. At 0.25 mg 2,4‐D/liter numerous curled and wrinkled leaves developed. Approximately 200 complete plants have been differentiated. after transfer to the 2,4‐D‐free medium. Root tip cells from five plants indicated that each had 20 chromosomes. After transplantation to soil, 10 to 15% of the plants survived and grew normally. The optimum embryo age for scutellar callus initiation was 18 days post‐pollination. Hormone combinations such as 1 mg 2,4‐D, 4 mg a‐naphthaleneacetic acid (NAA), and 0.05 mg 6‐(γ,γ‐dimethyl allylamino)‐purine (2iP)/liter may increase the efficiency of scutellar callus initiation.
Variability in Metabolism of Individual Axes of Soybean Seeds and Its Relationship to Vigor1
Authors: Yaklich Robert W. , Abdul‐Baki Aref A.
Published: July 2010

Vigor was measured on individual seeds of soybean (Glycine max L. ‘Lee‐68’) by an isotopic method for determining total uptake, incorporation and leaching of 14C‐leucine fed to the individual axes. Results were similar with 32P, which reduced the time necessary for a determination because uptake of 32P by the axis was measured without extracting the tissue.

The isotopic and conductivity methods for determining leachates were compared. More sugars and amino acids were leached from deteriorated than from vigorous seeds, whether the components were derived from an endogenous source, (e.g., stored food reserves) or from the incubation medium.
Relation of Flag Smut Incidence to Semidwarf Growth Habit in Wheat Isolines1
Authors: Allan R. E.
Published: July 2010

Incidence of flag smut [Urocystis agropyri (Preuss) Schroet.] was related to the presence of semidwarf genes of wheat (Triticum aestivum L. em. Thell.) derived from ‘Norin 10’/‘Brevor,’ 14 and ‘Suwon 92.’ For 2 years at two sites, tests were conducted on five isoline populations of four genetic backgrounds with varying degrees of flag smut susceptibility. Isolines with two semidwarf genes had higher incidences of smut than standard‐height phenotypes in 9 of 10 comparisons (P = 0.05). One‐gene semidwarf isolines were more heavily smutted than standard‐height lines in 7 of 10 comparisons (P = 0.05). The two‐gene, one‐gene semidwarf, and standard‐height phenotypes averaged 62.9, 56.3 and 47.6% smutted tillers, respectively, for all populations during the 2 years. The proportions of smuttedtillers of all populations for both years for two‐gene and one‐gene phenotypes vs. the standard‐height phenotypes were 1.32 to 1.00 and 1.18 to 1.00, respectively. The two‐gene semidwarf isolines were significantly more heavily smutted than their one‐gene semidwarf sibs in 6 of 10 comparisons (P = 0.05). On an overall basis, the proportion of smutted tillers of the two‐gene vs. one‐gene phenotype was 1.12 to 1.00. The relation between semidwarf genes and increased incidence of flag smut was indirect and should not preclude the development of two and one‐gene semidwarf cultivars with adequate resistance. Breeders should recognize that semidwarf types may be potentially more vulnerable to losses from flag smut than nonsemidwarf types.
Inheritance of Node, Branch, and Spikelet Number in Oat Panicles. Diallel Analysis of F1 and F21
Authors: Chae Young‐am , Forsberg R. A.
Published: July 2010

The nature of gene action and inheritance controlling oat (Avetta sativa L.) panicle traits was determined from F1 and F2 generations of a diallel cross among seven parents. Traits measured were panicle length (PL), number of nodes/panicle (NNP), number of brances/node (NBN), number of branches/panicle (NBP), number of spikelets/node (NSN), and number of spikelets/panicle (NSP).

Additive genetic variances were significantly different from zero in both 1972 and 1973 and in both F1's and F2's, and additive effects of genes were more stable than dominance effects. The degree and direction of dominance varied with traits, generations, and years, except for NSN and NSP which remained at partial dominance in both years and generations.

Positive and negative alleles were equally distributed among parents for PL, NBN, NSN, and NSP, but not for NNP and NBP. Long PL and large NSN and NSP were controlled by recessive genes, while dominant genes controlled large NBN and NBP. The dominant and recessive genes controlling PL and NSP were in equal proportions in the parents, while an excess of dominant genes existed for NBN and NSN.

At least one effective factor existed for PL; two for NNP, NBN, and NBP; and three for NSN and NSP. Relatively larger heritabilities were obtained for PL (42 to 80%), NSN (79 to 82%), and NSP (63 to 79%). NSP appears to be the most reliable selection criterion for yield improvement.
Influence of Temperature on the Growth of Erodium botrys and Trifolium subterraneum1
Authors: Guerrero F. P. , Williams W. A.
Published: July 2010

Temperature effects on the vegetative growth of broadleaf filaree, Erodium botrys (Cav.) Bertol., and subterranean clover, Trijolium subterraneum L., were studied at three diurnal temperature regimes: low (5 to 15 C), medium (10 to 20 C), and high (15 to 25 C). The objective of this study was to evaluate the response of these species to temperatures that reflect the conditions of the annual grassland type during the seedling stage. Chambergrown plants were harvested periodically over a 5‐week period.

Filaree was less sensitive to low temperatures and exhibited a temperature optimum between 10 to 20 C and 15 to 25 C, whereas sub clover showed a linear increase in relative growth rate with temperature up to 15 to 25 C.

Although sub clover demonstrated a more efficient photosynthetic system, i.e., a greater net assimilation rate, filaree had a higher photosynthetic capacity as shown by a greater leaf area ratio. Filaree partitioned more assimilate into leaf tissue than sub clover which in turn produced more stem and root tissue than filaree. These results indicate that filaree is favored when late fall rains occur along with lower temperatures.
Nitrate Reductase Activity of Grain Sorghum Leaves as Related to Yields of Grain, Dry Matter, and Nitrogen1
Authors: Eck H. V. , Wilson G. C. , Martinez Tito
Published: July 2010

Eleven grain sorghum (Sorghum bicolor L. Moench) hybrids were grown in the field and growth chamber. Leaf blade samples were assayed by in vitro and in vivo procedures for nitrate reductase activity (NRA) to i)termine NRA of the hybrids, ii) examine relationships between NRA and grain and N yields, and iii) determine whether NRA of growth chamber‐grown plants are indicative of those of field‐grown plants. Among hybrids, differences in yields of grain, dry matter, and grain protein and in in vitro NRA were significant though comparatively small. Seven hybrids had similar N input: accumulation ratios while four had lower ratios. This variation in N input:accumulation ratios, precludes the use of NRA, as assayed here, as a criterion for screening grain sorghum cultivars for N accumulation ability. Also, NRA values of young growth chamber‐grown plants were not indicative of those of field‐grown plants.
Effects of Fall Mowing on Winter Survival of Lovegrass Strains1
Authors: Voigt P. W.
Published: July 2010

Evaluating winterhardiness of perennial forages is difficult because of the irregularity of severe winters adequate for testing relatively hardy materials. The objective of this experiment was to examine fall mowing as a tool to increase differential winter injury among lovegrass (Eragrostis sp.) strains. Seventeen lovegrasses were mowed in early October, late October, and mid‐November, during each of 4 years at Woodward, Okla. Control treatments, late winter mowed or unmowed, were included. After mild to moderately severe winters, fall mowing increased winter survival discrimination among lovegrass strains. After one severe winter, discrimination was decreased.

Most correlations between survival of strains in the control treatment after a severe winter and survival after fall‐mowing treatments during milder winters were relatively high. After mild winters, strain survival was strongly correlated with limited late fall regrowth. After the severe winter, survival was closely associated with the presence of live, green leaves in late fall. Late fall regrowth and leaf color accounted for 84% of the variation in control survival after that winter. Survival after fall‐mowing stress, and the associated late fall regrowth and leaf color scores, appear to be important predictors of winter survival ability in Eragrostis.
Effects of Storage Conditions, Packaging Materials, and Moisture Content on Longevity of Crimson Clover Seeds1
Authors: Clark D. C. , Bass L. N.
Published: July 2010

Seeds of crimson clover (Trifol ium incarnatum L.), dried to 5 and 6.9% moisture content, were packaged in containers constructed of various heat‐sealable materials and stored up to 11 years at a wide range of temperature and relative humidity (RH) conditions. Materials containing foil provided good moisture and germinationprotection. Under high temperatures (30 C) or high RH (90%), seeds in good moisture‐barrier containers lived longer than did seeds in poor moisture‐barrier containers. Under favorable storage conditions, protective packaging had less effect on seed longevity.
Use of Crickets in a Bioassay of Forage Quality in Tall Fescue1
Authors: Asay K. H. , Minnick T. R. , Garner G. B. , Harmon B. W.
Published: July 2010

Feeding trials were conducted to test the validity of using crickets (Acheta domesticus L.) to assay the quality of forages intended for ruminant feed. Diets of forage from diverse genotypes of tall rescue (Festuca arundinacea Schreb.) produced significant differences in survival and growth rate of crickets. Certain tall rescue genotypes were consistently ranked high on the basis of cricket performance compared to others that caused almost complete mortality in all trials. Survival and growth rate were not related to in vitro digestibility; tensile strength of the leaves; and concentration in the forage of lignin, acid detergent fiber, cellulose, and ash.

A feeding trial was conducted to study the relationship between cricket performance and toxicity of tall rescue to cattle. Anion, cation, and neutral fractions, were prepared from extracts of two genotypes representing opposite extremes on the basis of cricket performance in earlier trials. These and other extracts of interest were included in cricket diets. Results indicated the presence of an inhibitory substance in the cation fraction of the genotype found to cause a high rate of mortality. This entity is probably not associated with “fescue foot” toxicity in cattle, because the toxic principle responsible for that syndrome is most likely in the anion fraction. However, the effect of the cation fraction and other forage attributes associated with cricket survival and growth on the performance of ruminants, merits additional study.
Effects of a Single Height Gene (DW3 of Sorghum on Certain Agronomic Characters1
Authors: Campbell I. G. , Casady A. J. , Crook W. J.
Published: July 2010

Results of a study, to determine more closely the degree of dominance of the Dwa gene of sorghum [Sorghum bicolor (L.) Moench] and to investigate further the relationships between height and other agronomic traits, are reported. Isogenic lines of ‘Martin,’ ‘Plainsman,’‘Redlan,’ and ‘Tx403,’ homozygous for the dominant and recessive allele of Dws were compared with heterozygous lines produced from crosses of each short line to its tall counterpart.

Data were collected and analyzed for culm height, grain yield, test weight, kernel weight, panicles/plant, peduncle length, and node number. Height genotype influenced total yield, test weight, panicles/plant, and kernel weight, as well as culm height. Cultivar ✕ height interactions were observed for height, test weight, and kernel weight. Height appeared to be partially dominant. The degree of dominance recorded for Martin, Plainsman, and Redlan was 0.70, 0.70, and 0.82, respectively. Yields of the heterozygous lines were not significantly different from those of the corresponding homozygous tall lines. In general, heterozygous lines had test weights and kernel weights equal to those of the tall homozygous fines and higher than those of the short parents. Heterozygous lines tended to have more panicles/plant than did either the tall or short lines.
Influence of Two Different Dwarfing Sources on Yield and Protein Percentage in Semidwarf Wheat1
Authors: Pepe John F. , Heiner Robert E.
Published: July 2010

Two wheat cultivars (Triticum aestivum L. em. Thell.) having different dwarfing genes were crossed and 51 semidwarf F5 progeny lines were evaluated for yield and grain protein percentage. ‘Era’ has the sd2 gene from Norin 10‐Brevor, Selection 14 and the other parent ‘Chris Mutant‐MN6616M,’ obtained from mutagen‐treated ‘Chris,’ has a single gene for height reduction. The two dwarfing genes are independently inherited. Each of the progeny lines was crossed to Era and F2 height segregation patterns were examined to establish which dwarfing gene was present; 30 lines had the sd2 gene and 21 had the Chris Mutant gene.

A wide range of yields and protein contents were found in both groups of lines, suggesting random recombination between genes for height, grain yield, and protein percentage. Therefore, either dwarfing source could be used effectively in breeding programs to develop shortstatured cultivars with high yield and high protein percentage
Breeding Alfalfa Which Regenerates from Callus Tissue in Culture1
Authors: Bingham E. T. , Hurley L. V. , Kaatz D. M. , Saunders J. W.
Published: July 2010

Tetraplold alfalfa (Medicago sativa L.) germplasm, in which two‐thirds of the plants are capable of regeneration from callus tissue in culture, has been developed by recurrent selection. It descends from one ‘DuPuits’ and four ‘Saranac’ clones which regenerated in the cycle 0 population. Frequency of regeneration was 12% in cycle 0, about 50% in cycle 1, and 67% in cycle 2. Seed produced by hand‐intercrossing 75 plants regenerated from cycle 2 has been termed ‘Regen‐S’ (Regen for regeneration; S for Saranac). It is purple‐flowered and phenotypically similar to Saranac. One‐gram lots of Regen‐S seed are presently available for distribution, and larger amounts are expected to be available in late 1975. A yellow‐flowered regenerator ‘Regen‐Y,’ is now being bred from selections out of ‘Rhizoma,’ ‘Rambler,’ and ‘Drylander.’ Small amounts of Regen‐Y seed are also presently available, thus providing a contrasting qualitative genetic marker stock.
Temperatures in Early Post‐Transplant Growth: Influence on Leaf and Floral Initiation in Tobacco1
Authors: Raper C. David , Thomas Judith F. , Wann Mien , York Emory K.
Published: July 2010

The quantitative effects of temperature on apical meristem and leaf development were investigated in a flue‐cured cultivar of tobacco (Nicotiana tabacum L.). while the interval between emergence and expansion of successive leaves was progressively reduced by increasing temperatures after transplanting, the plastochron (or interval between differentiation of successive primordia) was increased by increasing temperatures. An apparent lag period, during which little evidence of activity was observed for apical meristem development, was prolonged for the highest and lowest temperatures. The day/night temperatures included in the study were 18/14, 22/18, 26/22, 30/26, and 34/30 C.
Short Internode Character in Soybeans and its Inheritance1
Authors: Kilen T. C. , Hartwig E. E.
Published: July 2010

A cross was made between a soybean [Glycine max (L.) Merr.] type having very short internodes and a highly productive breeding line with multiple disease resistance. The donor of the short internode character ‘PI 227224,’ was very low yielding, primarily because of its susceptibility to most diseases common to soybeans in the area. Plants with short internodes could be easily identified in the segregating populations. All F2 plants expressing the character bred true, whereas about half of the F2 population segregated for internode length in the F3 generation. Heterozygous F2 plants could not be distinguished from plants homozygous for normal internode length. These data indicated that the short internode character is probably determined by a single recessive gene.
Optimal Significance Levels for Application of the Least Significant Difference in Crop Performance Trials1
Authors: Carmer S. G.
Published: July 2010

Studies in the context of crop performance trials were undertaken to determine the effects of the frequencies of three types of statistical errors, the relative scriousness of these errors, and the frequency distribution of true differences between means in the application of the least significant difference (L.S.D.) for pairwise multiple comparisons. The results indicate that the optimal choice of significance level, α, for the L.S.D. depends on the seriousness of type I and type III errors relative to type II errors. Arguments are presented supporting the use of significance levels in the range α = 0.20 to 0.40 for the L.S.D. when making pairwise multiple comparisons between observed means from crop performance trials.
Excision Effects on Leaf Water Potential of Five Herbaceous Species1
Authors: Baughn J. W. , Tanner C. B.
Published: July 2010

Dewpoint hygrometers were used to compare the in situ water potential of a leaf with the potential of a tissue piece excised from the same leaf and measured either by a hygrometer or psychrometer. Excised tissue potential was found to average 1.0 to 3.0 bars lower (drier), depending on species and water potential range, than the in situ potential for potato (Solanum tuberosum L.), sunflower (Helianthus annuus L.), pepper (Capsicum annuum L.), and soybean (Glycine max L.). With oat (Avena sativa L.) the potential increased after the tissue was excised. Internal tissue changes following excision contributed significantly to the potential changes in oat and soybean. Internal changes could not be separated from tissue drying for the other three species. Loss of tissue water during sample preparation and confinement in sample holder was superimposed on the internal shifts; drying losses appeared greatest for the psychrometer, on the average.

All our data were obtained on glasshouse‐grown plants, so there is no immediate extrapolation of our data to field‐grown plants, nor to other species. It is clear, however, that water potential methods requiring excised tissue are liable to incur significant errors from the excision, especially in the wet range where such errors can be relatively large.
Recovery of Hardened Barley from Winter Injuries1
Authors: Olien C. R. , Marchetti B. L.
Published: July 2010

A distinct pattern of injury is caused by high intensity freezing. This type of stress results from rapid transfer of latent heat as the temperature slowly decreases (1 C/hour) in plant tissues at a high moisture content. Because the high moisture content is induced by flooding before freezing, effects of flooding and freezing were compared and distinguished. The roots and lower crown tissues of ‘Hudson’ barley (Hordeum vulgare L.) are severely injured by high intensity freezing, while the leaves and upper crown tissues are relatively unaffected. Surgical removal of injured tissues at the start of recovery, before degeneration had occurred, significantly improved survival. Detoxification mechanisms might affect winterhardiness.

Preliminary tests indicated that degenerating root tissues became generally toxic during the first few days of incubation at room temperature. New root formation from vegetative barley plants, seed germination of barley, and growth of Bacillus subtilis Cohn em. Prazm. were inhibited by association with degenerating root tissues. This general toxicity may affect winterhardiness by influencing recovery. Secondary degeneration of injured roots and crown tissues did reduce survival by affecting crown meristems. However the aseptic effect might aid in control of infection.
Recurrent Selection for Cold Tolerance in Maize1
Authors: Mock J. J. , Bakri A. A.
Published: July 2010

We conducted experiments in 1973 and 1974 (planted each year as early as possible in the spring) to evaluate effectiveness of recurrent selection for cold tolerance in two Iowa maize (Zea mays L.) breeding populations, BSSS2(SCT) and BSSS13(SCT). Progress from selection for cold tolerance was measured by changes in percentage emergence, emergence index (based on emergence rate), and seedling dry weight. Changes in other agronomic traits were studied also.

Relatively more progress for improved cold tolerance was realized from two cycles of recurrent selection in BSSS13(SCT) than from three cycles of recurrent selection in BSSS2(SCT). Percentage emergence and seedling dry weight of BSSS13(SCT) were improved 8.4%/cycle and 0.6 dg/cycle, respectively. These traits did not respond consistently to selection within BSSS2(SCT). Emergence index was not changed by selection in either population. Also, one cycle of selection based on data collected from growth‐chamber plantings of both populations did not choose significantly different genotypes from those chosen by selection based on data collected from field plantings.

The C2 cycle of BSSS13(SCT) was characterized by more vigorous seedling and juvenile plant growth, an earlier flowering date, and a lower harvest moisture than the C0 cycle. The C3 cycle of BSSS2(SCT) showed an earlier flowering date, shorter mature plant height, and lower harvest moisture than the C0 cycle.

Grain yields of advanced selection cycles of BSSS2(SCT) were lower than, and those of BSSS13(SCT) were equal to, that of the highest‐yielding hybrid check.
Alfalfa Seed Yields from Seeded Rows vs. Spaced Transplants1
Authors: Rincker Clarence M.
Published: July 2010

This study was conducted to determine the best procedure to follow for a maximum seed increase from a limited supply of stock alfalfa (Medicago sativa L.) seed. Seedlings of ‘Arc’ alfalfa transplanted 30.5, 61, and 122 cm apart in 91‐cm rows produced similar seed yields in all plant spacings during the year of establishment, and significantly greater yields than did seeded rows. Seed yields in the second and third harvest years did not differ among the four plant spacings; all yields exceeded 1,125 kg/ha. Seed yields from widely spaced plants (8,970 plants/ha) equaled those from closely spaced plants (35,879 plants/ha). Based on these results, the maximum initial seed increase from limited alfalfa stock seed would be obtained by transplanting seedling plants in the field at spacings that give 9,000 to 10,000 plants/ha.
Translocation of 14C‐labeled Assimilate and Photosynthesis in C3 and C4 Species1
Authors: Stephenson R. A. , Brown R. H. , Ashley D. A.
Published: July 2010

A survey of 17 C4 and 17 C3 species of higher plants was made in two experiments to determine differences in the percentage of 14C‐assimilate translocated in 6 hours. Leaves were labeled for 15 min with 14CO2 in the light. In one experiment net photosynthesis was also determined on leaves labeled with 14C. C4 plants exported more, and C3 species less, than 49% of the assimilated 14C in 6 hours. There were only four exceptions to this division in 49 means reported. These exceptions were cases where C4 species translocated less than 49% of the labeled assimilate. The C4/C3 ratios for translocation percentages were 1.55 and 1.67 for the two experiments. The C4/C3 ratio for net photosynthesis was 1.44. The correlation between net photosynthesis and translocation had a significant (P < 0.05) but not a high coefficient (r = 0.59). It is concluded that although net photosynthesis and percentage of 14C assimilate export are related, some other factors also play significant roles which affect this relationship.
A Correct Logarithmic Transformation for Standardizing Multiplicative Trait Variables1
Authors: Driscoll M. F. , Abel G. H.
Published: July 2010

The subject of this article is the logarithmic transformation, log(X/σ) − log(μ/σ), recently introduced and used by J. E. Grafius and R. L. Thomas to convert multiplicative trait variables into additive ones and to standardize the scales on which the variables were measured. It is shown that the transformation fails to achieve the second of these objectives.

The transformation (log X − v)/т is introduced and is shown to meet both of the desired aims. Then the two transformations are compared using three trait variables from an experiment on safflower, Carthamus tinctorius L. This comparison indicates that the use of the first transformation where the second is called for could lead to erroneous conclusions. The results of other work in progress verify this conclusion.
Sensitivity of Tef [Eragrostis Tef (Zucc.) Trotter] to Removal of Floral Parts1
Authors: Berhe Tareke , Miller Dwane G.
Published: July 2010

Various degrees of mechanical injury were applied to tef [Eragrostis tef (Zucc.) Trotter] florets and the floral‐sensitivity to mechanical manipulations assessed by the number of seeds set. Complete absence of seed set was recorded only when all three anthers of each floret were removed. Artificial application of pollen to completely emasculated florets did not improve seed set. Removal of lemma, palea, or glumes from basal florets resulted in 86, 87, and 90% seed set, respectively. Even in florets with the lemma, palea, and glumes all removed a 13% seed set was obtained. Emasculation of one, two, and all three anthers reduced seed set to 80, 36, and 0%, respectively.

Sensitivity of the ovary was observed to be most closely associated with the removal of anthers. It is suggested that substances are produced in the anthers that regulate the later stages of ovary development and maturation.
Interspecific Hybridization in Trifolium L., Sect. Trifolium Zoh. I. Diploid Hybrids among T. alpestre L., T. rubens L., T. heldreichianum Hausskn., and T. noricum Wulf.
Authors: Quesenberry K. H. , Taylor N. L.
Published: July 2010

Interspecific hybrids of Trifolium alpestre L. ✕ T. heldreichianum Hausskn. and reciprocal, T. alpestre ✕ T. rubens L. and T. rubens ✕ T. noricum Wulf. were produced by hand pollination in a greenhouse. Only the T. alpestre ✕ T. heldreichianum and T. alpestre ✕ T. rubens hybrids flowered. Hybridization barriers included apparent embryo abortion in the T. rubens ✕ T. alpestre and T. rubens ✕ T. heldreichianum cross, total F1 seedling inviability in the T. heldreichianum ✕ T. alpestre and T. rubens ✕ T. noricum cross and poor F2 seed germination and survival in the T. alpestre ✕ T. heldreichianum and T. alpestre ✕ T. rubens hybrids.

Hybrids of T. alpestre ✕ T. heldreichianum and T. alpestre ✕ T. rubens had 16 somatic chromosomes and a mean of 7.95 and 7.77 bivalents per Pollen Mother Cell (PMC) respectively. No cells with multivalents were observed and frequency of laggards at anaphase I and micronuclei at the quartet stage was less than 0.20 per PMC. Pollen stainability of T. alpestre ✕ T. heldreichianum and T. alpestre ✕ T. rubens was 53 and 51%, respectively.

Self compatibility was dominant to self incompatibility, and expressions of rhizomes and leaf mark were dominant to absences of rhizomes and leaf mark in the T. alpestre ✕ T. heldreichianum hybrid. Presence of rhizomes was also dominant in the T. alpestre ✕ T. rubens hybrid.

Second‐generation hybrids were produced by selfing; intercrossing and backcrossing to their parents. No hybrids were produced by crossing either of the interspecific hybrids with red clover, T. pratense L.
Evaluation of Verticillium Wilt Tolerance in Upland Cotton Relative to Lint Yield Reduction1
Authors: Marani A. , Yaacobi Y. Z.
Published: July 2010

Field experiments were conducted to compare methods of evaluating the tolerance of upland cotton (Gossypium hirsutum L.) to Verticillium dahliae Kleb. by visual symptoms. Good differentiation between susceptible and tolerant cultivars was obtained by observing foliar symptoms after the middle of the flowering period.

Correlation studies indicated that foliar symptoms explained 31 to 45% of the variation in lint yield among cotton breeding lines and cultivars in a wilt‐infested field, vascular discoloration at the base of the stem explained 25 to 29%, and vascular discoloration at a height of 40 cm explained 6% or less of that variation. Similar results were obtained when the dependent variable was the difference between lint yield in the infested field and mean lint yield of the same lines grown in two wilt‐free locations. Effective screening for wilt tolerance in Israel appears possible by observing foliar symptoms during the second half of the flowering period, provided the field is relatively uniformly infested by the fungus and suitable temperatures prevail.
Association Between Percent Total Alkaloids and Other Traits in Flue‐cured Tobacco1
Authors: Chaplin James F. , Weeks W. W.
Published: July 2010

The relationships between percent total alkaloids and nine agronomic and chemical traits were studied in isogenic lines derived from 10 cultivars of flue‐cured tobacco (Nicotiana tabacum L.). Isogenic lines with low total alkaloids percentage (approximately 0.20%) were compared with their “normal” recurring parents (total alkaloids 1.85 to 2.70%). The differences in traits other than alkaloid levels between the low alkaloid lines and their recurrent parent should reflect physiological associations (pleiotropism) and/or genetic linkages. Yield, grade index, total N, and reducing sugar content in the low alkaloid lines were lower than in the normal flue‐ cured cultivars. Chlorophyll contents, at time of harvest, were higher in the low alkaloid lines than in their recurrent parent. Alkaloid levels had little or no association with plant height, leaves per plant, or days to flower.
Independence of Imbibitional Chilling Injury and Energy Metabolism in Corn1
Authors: Cohn Marc Alan , Obendorf R. L.
Published: July 2010

Energy metabolism of 5 (low) and 13% (high) moisture Zea mays L. inbred ‘Oh51A’ kernels was measured at 0, 12, 24, and 48 hours at 25 C subsequent to imbibition at 5 C. Radicle growth was measured at 1, 2, 3, and 4 days. The interaction of low kernel moisture with imbibition at 5 C resulted in reduced radicle growth in seedlings. Oxygen uptake of whole kernels after imbibitional chilling was independent of initial kernel moisture. Differences in initial moisture also did not alter ATP levels of embryos and embryonic axes after chilling. ATP increased about 20‐fold and adenylate energy charge of embryos increased from 0.2 to 0.8 during hydration at 5 C irrespective of initial moisture content. Mitochondria isolated from embryos of low moistttre kernels exhibited slightly higher respiratory rates 24 hours after cold imbibition but not at other sampling times. ADP/O .ratios and respiratory control ratios (succinate substrate) of isolated mitochondria were not altered by initial kernel moisture. A disruption of energy metabolism is not a primary cause of kernel moisture‐mediated imbibitional chilling injury.
Condensed Tannins in Herbaceous Legumes1
Authors: Sarkar Subodh K. , Howarth Ronald E. , Goplen Bernard P.
Published: July 2010

Thirteen herbaceous legumes were examined for the presence of condensed tannins (flavolans). Flavolans were not present in herbage from Astragalus cicer L., Melilotus officinalis L., Medicago sativa L., Trifolium pratense L., T. repens L., and Vicia cracca L. Flavolans were present in herbage from Coronilla varia L., Lotus corniculatus L., Lespedeza cuneata Don., Onobrychis viciaefolia Scop., T. arvense L., T. campestre Schreb., and T. dubium Sibth. The absence of tannins from A. cicer, which is reported to be a nonbloating legume, may be an exception to the generalization that tannins are responsible for the prevention of bloat in ruminants grazing nonbloating legume forage crops.

Flavolans were extracted from the tannin‐bearing species with methanol‐water (1:1) and were partially characterized to determine whether differences in the composition of flavolans might explain variation in nutritive value of legume forages. Flavolans were characterized by: identification of free monomer flavanols; the number of flavolan bands on paper chromatograms; and identification of compounds produced by degradation of flavolans in acidic solution Flavolans of all species examined were proanthocyanidins, including both procyanidins and prodelphidins. A procyanidin was present in L. cuneata and C. varia, crops which are reported to have low nutritive values, but the same procyanidin was not present in O. viciaefolia and L. corniculatus, crops which have high nutritive values. This work demonstrates that herbaceous legumes vary in flavolan composition and suggests that such variation may be related to differences in nutritive value.
Relationships of Genes for Reaction to Stem Rust from ‘Marquis’ and ‘Reliance’ Wheat to Other Sr Genes1
Authors: Williams N. D. , Kaveh Hossein
Published: July 2010

We determined the allelic and linkage relations among genes for stem rust (Puccinia graminis Pers. f. sp. tritici Eriks. & E. Henn.) resistance in wheat lines designated Mq‐A, Mq‐B, Mq‐C, and Rl‐B‐1, which were derived from crosses of ‘Little Club’ with ‘Marquis’ or ‘Reliance’ wheat (Triticum aestivum L. em Thell.). The four derived lines were crossed with 14 tester lines having genes for resistance known to be located on specific chromosomes of ‘Hope,’ ‘Thatcher,’ ‘Red Egyptian,’ ‘Timstein,’ and an atypical Marquis selection. All F1's were selfed, and certain F1's were testcrossed with Little Club. The F2's and testcross‐F1's were tested for seedling reaction to races 111, 121, or 29 of P. graminis f. sp. tritici. Segregation for resistant and susceptible seedlings in the F2 and testcross populations indicated nonallelism, and absence of segregation indicated allelism or close linkage. The gene for resistance in Mq‐A was the same as, allelic to, or closely linked with Sr18 on chromosome 1D of Hope. Sr19 in Mq‐B was linked with Sr9a on chromosome 2B of Red Egyptian (p = 0.24 ± 0.03) and with Sr9d on 2B of Hope (p = 0.24 ± 0.02). A gene in Rl‐B‐1 for resistance to culture 111‐SS2 of race 111 was the same as, allelic to, or closely linked with Sr16 on chromosome 2B of Thatcher. One of two genes in substitution line Chinese Spring(Mq‐2B) was Sr16. A gene in Rl‐B‐1 for resistance to culture GB121‐1 of race 121 was the same as, allelic to, or closely linked with Sr5 on chromosome 6D of Thatcher. Sr20 from Mq‐C segregated independently of the other genes for resistance.
Porometer Cup to Measure Leaf Resistance of Pineapple1
Authors: Bartholomew D. P. , Kadzimin S. B.
Published: July 2010

The lack of information on the response time and calibration characteristics of the available porometer leaf cups at high diffusive resistances caused us to design and construct a teflon porometer leaf cup suitable for measurement f the very high epidermal diffusive resistances (re) encountered with pineapple [Ananas comosus (L.) Merr.] The cup was calibrated to diffusive resistances near 200 sec cm−1 and calibration was linear throughout the range. Measurements on pineapple confirmed that this species has high midday re with values for field grown plants estimated to exceed 400 sec cm−1 on a day with full sun. Minimum resistances of 5 to 10 sec cm−1 were reached at about 1800 hours and early morning values were comparable until 2 to 3 hours after sunrise. The data suggest that the water economy of the pineapple plant is enhanced by increased diffusive resistance at higher levels of radiation and temperature.
Alien Chromosome Controlling Sporophytic Sterility in Common Wheat1
Authors: Maan S. S.
Published: July 2010

Common wheat plants (Triticum aestivum L. em Thell.) having a monosomic or a disomic substitution (2n=42;20″+l′+l′ or 2n=42;20+l″, respectively) of an Aegilops longissima S. & M. chromosome were crossed as males to a set of ‘Chinese Spring’ telosomic or isosomic stocks. F1 plants were examined for kernels/spike, meiotic chromosome number, and chromosome pairing relationships. Results indicated that: 1) the afien chromosome was homoeologous to and substituted for 4A of wheat, 2) the missing wheat chromosome arms did not influence the sporophytic control of sterility of F1 plants, and 3) the male gametes without the critical alien chromosome were not transmitted.
Stand Establishment of Wheat Lines under Different Levels of Water Potential1
Authors: Gul Azam , Allan R. E.
Published: July 2010

Seedling emergence and the growth of seedlings of 93 wheat (Triticum aestivum L. em Thell.) lines, developed by recurrent selection for improved seedling vigor, and tour check cultivars were studied at four soilwater levels in laboratory tests and at different planting depths and locations in three field tests. Both studies revealed that the lines differed markedly in their emergence characteristics. Emergence rate index (ERI) was high for number of lines in all four soil water potentials (—2.2, —6.0, —10.2, —14.4 bars) and in field tests.

The time required for emergence nearly doubled for each decrease of water potential of —4 bars within the range studied. Total stand, coleoptile length, seedling height, and root weight were similarly progressively reduced as water potential decreased.

Total stand, coleoptile length, and seedling height were inconsistently related to ERI in laboratory tests, but were generally related in the field tests. Likewise, root weights of the nine promising lines were inconsistent with ERI at the three higher water potentials but were correlated (r = 0.93) at the lowest water potential the laboratory tests.
Sorghum Genotype Variation in Stomatal Sensitivity to Leaf Water Deficit1
Authors: Henzell R. G. , McCree K. J. , Van Bavel C. H. M. , Schertz K. F.
Published: July 2010

Leaf diffusive resistance and its variation among lines and their hybrids were determined in Sorghum bicolor (L.) Moench. As plants were progressively stressed for moisture leaf diffusive resistance and leaf‐water potential were monitored to determine their relationship in these materials in a growth chamber at College Station, Texas. Stomatal sensitivity varied significantly among the entries during progressive water deficit. The stomatal conductance of leaves of ‘Alpha’ and ‘Shallu’ decreased rapidly as leaf water potential declined, whereas it declined more slowly in ‘I.S.1598C’ and ‘M35‐1’. In general the behavior of the F1 hybrids was similar to that of the more sensitive parent, but the correspondence was not consistent. The results suggest that stomatal sensitivity may be an important element of intergenotype variation in resistance to drought.
Protein Concentration, Concentration of Protein Fractions, and Amino Acid Balance in Oats1
Authors: Peterson David M.
Published: July 2010

The relationships among protein concentration and fractional protein composition in oat (Arena sativa L.) groats were investigated. Samples used were obtained from two locations in Wisconsin, a rate and type of N experiment in Arkansas, and a rate and time of application of N experiment in Michigan. The Michigan samples were also analyzed for amino acid composition. Results indicated that an increase in the total protein level was primarily related to an increase in the level of the globulin fraction. In the Wisconsin experiment, samples of six cultivars grown in Waupaca County were higher in protein concentration than those grown in Rock County. The mean globulin percentage was significantly higher in the high protein samples, and accounted for nearly half of the increase in total protein. In samples of ‘Nora’ groats from Arkansas, globulins, prolamins, and glutelins all increased with increasing protein concentration, but the regression of globulins with total protein was highest (b=0.39). In the Michigan experiment, the globulin fraction was highly correlated with total protein for all three cultivars. In ‘Clintland 64,’ the percentage of glutelins was also strongly associated with total protein. As percentage of total protein increased, the amino acid balance was unchanged in the Michigan samples. I concluded that the amino acid balance in oat groats is relatively stable over a wide range of protein concentrations because the globulin fraction, whose amino acid composition is similar to that of the total protein, increases more than the other fractions with increases in total protein.
Genetic Variability for Mineral Concentration in Plants Related to Mineral Requirements of Cattle1
Authors: Hill R. R. , Guss S. B.
Published: July 2010

Many problems in plant and animal production are attributable to mineral imbalances in soils and in feed rations. The prevailing attitude has been that nutrient disorders in plants can be corrected by applying commercial fertilizers and that deficiencies in animals can be corrected by supplementing diets. Limited attempts have been made to exploit genetic, variability, in plants for accumulation of and reactions to minerals. Recent reviews amply illustrate the genetic variability for tolerance to adverse concentrations of some elements and the potential for their use on problem soils. Other mineral‐related agricultural problems may be attacked through plant breeding. We chose breeding for plant mineral concentrations that meet requirements for animal production to illustrate further the potential of genetic variability. We will emphasize how the genetic variability for mineral concentrations in plants may be exploited to more nearly balance animal diets, and, to a lesser extent, the modes of inheritance of mineral concentrations in plants.
A Proposal for Hybrid Wheat Utilizing Aegilops squarrosa L. Cytoplasm1
Authors: Franckowiak J. D. , Maan S. S. , Williams N. D.
Published: July 2010

The nucleocytoplasmlc interactions of Aegiiops squatrosa L. (2n=14,DD) cytoplasm and Triticum durum Desf. (2n=28;AABB) or T. aestivum L. em Thell. (2n=42,AABBDD) nuclei indicate that a new cytoplasmic male sterility‐male fertility restoration system can be developed for hybrid wheat production. The proposed system should be more efficient than those cytoplasmic male‐sterility systems that require breeding of R‐lines to produce fertile hybrids, because conventional wheat cultivars can be used as R‐lines in the new system. The D genome of common wheat contains genetic factor(s) for restoration of fertility of T. aestivum with A. squarrosa cytoplasm, and induced mutations may inactivate these critical gene(s). Therefore, seed of alloplasmic T. aestirum with A. squarrosa cytoplasm was treated with ethyl methanesulfonate (EMS). Nine male‐sterile mutants were selected and crossed with common wheats. Most mutants had monogenic or digenic inheritance for male sterility and produced normal F1 and F2 hybrids. The male‐sterile mutants can be used to develop male‐sterile A‐lines and maintainer B‐lines for the production of hybrid wheat if the sterility genes are specific for A. squarrosa cytoplasm.
Crop Temperature Modification and Yield Potential in a Dwarf Spring Wheat1
Authors: Fischer R. A. , Maurer O. R.
Published: July 2010

The influence of temperature on development, dry matter production, grain yield, and grain yield components of a high yielding dwarf spring wheat (Triticum aestivum L. em Thell ‘Yecora 70’) was studied at different stages of growth in the field. Crops were grown under conditions of high fertility and irrigation in northwest Mexico during 1972–73 and 1973–74. In each of four approximately 4‐week periods during the crop cycle, portions of the crop were enclosed in transparent chambers which were ventilated with cooled or heated air. Air temperatures inside the chambers averaged respectively, 1 to 2 C below or 2 to 7 C above air temperature outside.

Development was retarded slightly by cooling and hastened considerably by heating. Total dry weight at maturity and grain yield were reduced by increased temperatures at any stage other than the first. The biggest effects were seen in the second and third periods (end of tillering to beginning of grain filling), where a 1 C rise in temperature was associated with a 4% reduction in grain yield. This was largely related to effects on grains/m2 via changes in spikes/m2 and grains/spikelet. Temperature increases during the fourth or grain‐filling period reduced kernel weight in some situations and had no effect in others. The relevance of these results to other temperature studies and to possible avenues for increasing grain yield in Yecora 70 is discussed.
Variation in Fatty Acid Composition of Oat Groats from Different Cultivars1
Authors: Youngs V. L. , Püskülcü Halis
Published: July 2010

Relative concentration of six fatty acids was measured in oat (Avena sativa L.) groats from 15 cultivars grown in three locations in two crop years. Palmitic, oleic, and linoleic acids comprised over 95% of the acids measured. Ranges were: palmitic, 16.2 to 21.8%; oleic, 28.4 to 40.3%; linoleic, 36.6 to 45.8%. These fatty acids were related individually with total lipids to give these correlation coefficients: palmitic, r = −0.76 (P≤0.01); oleic, r = 0.91 (P≤0.01); linoleic, r = −0.85 (P≤0.01). Cultivars varied significantly (P≤0.01) for each fatty acid except stearic. Broad‐sense heritabilities of the three acids were high: palmitic, 91.4%; oleic, 98.6%,; linoleic, 95.7%.
Canopy Characters and Their Relationship to Spring Productivity in Bromus inermis Leyss1
Authors: Tan Wai‐Koon , Tan Geok‐Yong , Walton P. D.
Published: July 2010

A half diallel cross involving seven clones of smooth bromegrass (Bromus inermis Leyss.) was used in this study. The objective was to determine the genetic variability of canopy characters such as leaf number, leaf length, leaf area per tiller, leaf angle, leaf rigidity, tiller density and canopy height, and their relationships with spring forage yield. Significant general combining abilities were obtained for leaf number, leaf length, leaf area per tiller, leaf rigidity, tiller density and yield. Significant specific combining abilities were also detected for all characters except leaf rigidity. High narrow‐sense heritabilities were calculated for leaf area per tiller (53%) and tiller density (55%), whereas very low values were obtained for leaf angle (6%), and canopy height (14%). Phenotypic and genotypic correlations showed that tiller density and canopy height were positively correlated while leaf rigidity was negatively correlated with spring yield. However, path coefficient analysis revealed that leaf area per tiller and tiller density were the two major components affecting spring yield.