bluuebunny/crossref_metadata_2025 huggingface dataset:
Heritability of Verticillium Wilt Tolerance in Crosses of American Upland Cotton1
Authors: Roberts Carl L. , Staten Glen
Published: July 2010

Broad‐sense heritability estimates of tolerance to Verticillium wilt [Verticillium albo‐atrum (Reinke and Berth)] under severe field exposure in American Upland cotton (Gossypium hirsutum L.) were compared using F2 and F3 generations of tolerant ✕ susceptible crosses. Heritability estimates varied from 0 to .833, depending upon exposure level, generation tested, and type of parental tolerance present.

Tolerance to Verticillium wilt was found to be recessive for the crosses studied. Selection based on progeny row yield was effective when Verticillium wilt was severe.

Susceptible F2 plants produced homozygous susceptible F3 rows but progeny testing of tolerant F2 plants was necessary to detect escapes.
Natural and Mass Selection Estimates of Relative Fitness for the Soybean rps Gene1
Authors: Buzzell R. I. , Haas Jerry H.
Published: July 2010

Relative‐fitness estimates were obtained for the rps gene that controls susceptibility to phytophthora rot in the soybean [Glycine max (L.) Merr.] Composites of resistant and susceptible varieties carrying phenotypic markers were used. With natural selection under epiphytotic conditions, rpsrps was 75% as reproductive as RpsRps in 2 years and only 35% as reproductive in another year. Mass selection through sieving for larger seed further reduced the relative fitness of rpsrps. The estimates were applied to a theoretical bulk‐hybrid population segregating for Rps and rps to show the probable effects of natural and mass selection in increasing the proportion of resistant plants.
Effect of Tillering and Cool Nights on Photosynthesis and Chloroplast Starch in Pangola1
Authors: Chatterton N. J. , Carlson G. E. , Hungerford W. E. , Lee D. R.
Published: July 2010

Clonal propagviles of Digitaria decumbens Stent. were given night‐temperature treatments of 30, 10, 8, and 6 C, with day temperatures of 30 C. Chloroplasts of actively tillering plants accumulated little starch and NCE (net carbon dioxide exchange) rates showed no effect of cool nights. However, chloroplasts of nontillering plants accumulated starch during the day. When night temperatures were cool translocation was apparently reduced and the starch remained within the chloroplasts. The greater chloroplast starch content of nontillering plants after cool nights was negatively correlated (1% level) with NCE rates. Plants developing new tillers and therefore possessing large assimilate sinks had faster NCE rates than nontillering plants.
Chromosomal Location of a Dwarfing Gene in ‘Tom Thumb’ Wheat Derivative by Monosomic Analysis1
Authors: Morris Rosalind , Schmidt J. W. , Johnson V. A.
Published: July 2010

A winter wheat line of Triticum aestivum L. em. Thell. (aestivum group) segregating for a semidominant gene for dwarf stature from ‘Tom Thumb’ was crossed with ‘Wichita’ or ‘Cheyenne’ aneuploids. The F1 progenies segregated into two height groups in a ratio of 1:1. F2 disomic and noncritical monosomic progenies segregated in a ratio of 1 short:2 intermediate:1 tall. Monosomic analyses involving all chromosomes except 2A, 4B, and 6B indicated that the dwarfing gene was located on 4A. The heterozygous and hemizygous states of the gene had the same effect on height.
Diallel Analysis of Stalk Quality Traits in Twelve Inbred Lines of Maize1
Authors: Loesch P. J.
Published: July 2010

Sixty‐six inter se F1 crosses among 12 inbred lines of corn (Zea mays L.) were evaluated in two years at two locations. The inheritance of eight stalk traits was determined by means of diallel analysis. Significant differences among the 66 F1 hybrids were obtained in each trait. General combining ability (gca) and specific combining ability (sca) mean squares were statistically significant nearly every instance. The gca mean square was usually much larger than the sea mean square. Genotypic correlation coefficients between large stalk diameter and crushing strength, weight of stalk and crushing strength, and rind thickness and crushing strength were .72, .88, and .60, respectively. Weight of stalk section appears to be well suited for rapid screening purposes, whereas stalk density appears to be a poor trait to employ in a selection program. for the material studied, selection for high crushing strength will likely result, on the average, in strains characterized by increased size of stalk, weight of stalk, and thickness of rind. Selection procedures recommended for populations involving the lines tested were those which are effective in utilizing both the additive and nonadditive genetic variability.
Inhibitory Effects of Perloline to Rumen Fermentation in vitro1
Authors: Bush L. P. , Boling J. A. , Allen G. , Buckner R. C.
Published: July 2010

Inhibition of volatile fatty acid production and cellulose digestion by microorganisms of rumen fluid occurred at concentrations above 9.4 ✕ 10‐5 M perloline. Concentrations of 9.4 ✕ 10‐5 M perloline and less also inhibited cellulose digestion but stimulated volatile fatty acid production. Growth of two anaerobic cellulolytic bacteria was increased by 10‐4 M perloline, whereas growth of all the cellulolytic bacteria was completely inhibited at 10‐3 M. At perloline concentrations above 1.13 ✕ 10‐3 M rumen protozoa died rapidly, whereas 2.71 ✕ 10‐4 M had no noticeable influence on the viability of protozoa.
Relation of the Club Gene to Culm Length and Other Characters of Near‐Isogenic Wheat Lines1
Authors: Gul Azan , Allan R. E.
Published: July 2010

We studied the relation of the C gene to the length of the awn, the coleoptile, the first leaf, and the culm and its internodes, using near‐isogenic lines of Triticum aestivum L. The club and lax lines represented two contrasting backgrounds: ‘Suwon 92’ (a lax cultivar)/8*‘Omar’ (a club cultivar), and ‘Albit’ (a club cultivar)/7*‘Burt’ (a lax cultivar). The C gene reduced culm length in both the club and lax background. The C gene inhibited length of all internodes, with the most reduction occurring in the peduncle and progressively smaller reductions in lower internodes. Awn length was reduced, but not proportionally to culm length. First leaf length was reduced 6 to 10% in the presence of the C gene. No difference occurred in coleoptile length between the two spike types in the Omar background, whereas coleoptiles of the club lines were longer than those of the lax lines in the ‘Burt’ background.
Yield Stability Parameters for Sorghum in East Africa
Authors: Jowett D.
Published: July 2010

Yield data of single crosses, three‐way crosses and inbreds of Sorghum bicolor (L.) Moench, obtained in East Africa, are analyzed by previously described techniques on both an arithmetic and a log scale to obtain estimates of parameters describing yield stability over environments. Comparison of regression coefficients of yield on environmental index show that hybrids are more stable in terms of this parameter, but that there is no difference between three‐way and single crosses. In terms of deviations from regression, weak evidence is presented that indicates that three‐way crosses may be more stable than single crosses. This is interpreted as being due to population buffering. However, one single cross showed particularly low deviations, indicating that this may be a heritable characteristic. The analyses on the arithmetic scale and on the log scale are compared, with the conclusion that analysis on the log scale is preferable if varieties differ markedly in yield.
Growth Analysis of American Upland Cotton, Gossypim hirsutum L., with Different Leaf Shapes and Colors1
Authors: Karami E. , Weaver J. B.
Published: July 2010

Analysis of plant growth and development of biotypes of American Upland cotton (Gossypium hirsutum L.) with nine different combinations of leaf shape and color were made at two plant populations. The nine combinations of leaf shape and color were obtained by crossing Okra Leaf ‘Stoneville 7A’ BC4 with Red Leaf Stoneville 7A BC4 and then selecting the various leaf shapes and color combinations within the F2 population.

Okra Leaf (L° L°) was associated with low incidence of boll rot, number of vegetative branches, node number of first‐fruiting branch, dry weight of vegetative parts, leaf area, and with a shorter plant compared with normal leaf type. Okra Leaf also resulted in earlier maturity, higher harvest index, and higher seed cotton yield compared with normal leaf cotton. Okra Leaf had no effect on fiber length or fiber length uniformity, but caused a slight reduction in fineness and a slight increase in fiber strength.

The homozygous red color resulted in a significant reduction in seed cotton yield in an experiment with 45‐cm spacing within the row. There were no significant interactions between leaf shape and leaf color.

All measurements for intermediate (heterozygous) leaf shape were between the values found for Okra Leaf and normal leaf cotton.
Multiple Cottonseed Treatments: Effects on Germination, Seedling Growth, and Survival1
Authors: Ranney C. D.
Published: July 2010

This study evaluated the direct effect of, and interactions between, pesticides used as seed treatments on germination, seedling growth, and field survival of cotton (Gossypium hirsutum L.). Six nonmercurial protectant fungicides, N‐[(trichloromethyl)thio]‐4‐cyclohexene‐1,2‐dicarboximide (captan), bis(dimethylthiocarbamoyl)disulfide (thiram), 2‐(thiocyanomethylthio)benzothiazole (Busan 72), combinations of pentachloronitrobenzene + 5‐ethoxy‐3‐trichloromethyl‐1,2,4‐thiadiazole (Terracoat L21), tetrachloroisophthalonitrile + sodium‐p‐(dimethylamino) benzene diazosulfonate (chlorothalonil + Dexon), and pentachloronitrobenzene + sodium‐p‐(dimethylamino) benzene diazosulfonate (PCNB + Dexon); two systemic fungicides, 1,4‐dichloro‐2,5‐dimethoxybenzene (chloroneb) and 5,6‐dihydro‐2‐methyl‐1,4‐oxathiin‐3‐carboxanilide (carboxin); and the systemic insecticide, 0,0‐diethyl S‐[2‐(ethylthio)ethyl]phosphorodithioate (disulfoton), were used alone and in all combinations of the pesticide types. When used in a treatment, the protectant fungicide was applied first, followed by the systemic fungicide and the systemic insecticide. Evaluations included germination tests at standard conditions, at constant 20 C, and constant 30 C. Dry weight transfer (DWT) determinations were also made at 20 and 30 C. Percent seedling survival in the field 42 days after planting was determined.

Use of a protectant fungicide either significantly improved germination and seedling growth or did not affect these factors. A significant increase in seedling survival, 22 to 42%, resulted from the use of the various protectant fungicides. The inclusion of a systemic fungicide in the treatment combinations tended to reduce germination and DWT values but improved stands by 40%. Inclusion of the systemic insecticide in the treatment combinations resulted in reduced germination, DWT, and seedling survival (13%). Where the systemic insecticide was used, the inclusion of a systemic fungicide further reduced germination values but often resulted in significant increases in seedling survival. Significant interactions among the different types of chemical treatments and suggestions that temperature affected the treatment response indicate the need to identify combinations of chemicals for seed treatment that are safe and effective under various environmental conditions.
Inheritance of Resistance to Maize Dwarf Mosaic Virus1
Authors: Loesch P. J. , Zuber M. S.
Published: July 2010

We determined the inheritance of host resistance to MDMV for the inter se crosses among 10 inbred lines of corn (Zea mays L.). Trials were conducted in 2 years at two locations. Diallel analyses indicated that the general combining ability and the specific combining ability mean squares were statistically significant, but that the gca mean square was substantially larger than the sca mean square. Differences in MDM scores were noted between years and locations. Our results agree rather well with previous studies based on diallel analysis and generation mean analysis. Previous studies indicated that disease symptoms are expressed more intensely when competition from johnsongrass (Sorghum halepense L.) Pers., as well as from other forms of environmental stress, becomes extreme. Also, host reaction to MDMV is confounded with hybrid vigor. We conclude that these sources of bias would be minimized by evaluating F1 hybrids.
Evaluating Soft Wheat Quality of Early Generation Progenies1,3
Authors: Yamazaki W. T. , Donelson J. R.
Published: July 2010

A procedure is proposed for evaluating the milling and baking qualities of early generation soft wheat (Triticum aestivum L.) progenies. Twenty grams of wheat are ground for flour granularity and protein content determinations.A portion is reground and sifted, and tested for alkaline water retention capacity (AWRC). lqour granularity is associated with break flour yield during milling and with cake quality potential, while AWRC is correlated with cookie quality. A test line is considered to have suitable soft wheat quality potential if it is at least as low in protein and AWRC and at least as high in particle‐size index as a standard (commercial) cultivar.
Effect of Plant Height on Fiber Yield in Jute, Corchorus Olitorius L.1
Authors: Ahmed Sadeque U.
Published: July 2010

Six cultivars of jute (Corchorus olitorius L.) were used in a study to ascertain the effect of plant height on fiber yield. Results obtained suggest that one or more plant characteristics such as the amount of bast (secondary phloem tissue) affect net fiber yield more directly than plant height.
A Comparison of 14C‐Labeled Photosynthate Export from Two Leaf Positions in a Corn (Zea mays L.) Canopy1
Authors: Tripathy P. C. , Eastin John A. , Schrader L. E.
Published: July 2010

The time course and direction of 14C‐labeled photosynthate export from upper and lower leaf positions in a corn (Zea mays L.) canopy were compared at five different stages from silking to kernel maturity. Export of 14C‐assimilates was slower from the lower than from the upper position. Some of the difference was due to more accumulation of 14C in leaf starch at the lower position. The direction of export from a given leaf position changed as development progressed, indicating that sink demand strongly influenced the direction photosynthate moved. Transport of 14C from upper leaves was predominantly downward, whereas direction of export from lower leaves changed from downward to upward as the ear became the dominant sink.
Effects of Nutrient‐Media Composition on Growth of Seedlings from Intact Seeds and Excised Embryos of Maize (Zea Mays L.)1
Authors: Dahmen W. J. , Mock J. J.
Published: July 2010

Basal and complex agar‐sucrose nutrient media were compared for effects on growth of light‐grown seedlings from mature intact seeds and excised embryos of maize (Zea mays L.). Effects of auxin, 2, 4‐dichlorophenoxyacetic acid, also were studied.

Complex medium increased root growth of seedlings from intact seeds but did not affect root growth of seedlings from excised embryos. There were no nutrient media effects on shoot growth. No absolute requirement by cultured maize embryos for externally supplied auxin was demonstrated. In the basal medium, auxin inhibited root growth.
Resistance in Soybeans to the Mexican Bean Beetle: II. Reactions of the Beetle to Resistant Plants1
Authors: Van Duyn John W. , Turnipseed Sam G. , Maxwell James D.
Published: July 2010

Mexican bean beetles (Epilachna varivestis Mulsant) displayed differential preference reactions when fed foliage from resistant soybean (Glycine max (L.) Merrill) genotypes PI 229358, PI 227687, and PI 171451. These reactions included reduced longevity and fecundity in adults and weight loss and high mortality in larvae. These symptoms appeared similar to starvation and hypothetically resulted from reduced consumption of resistant foliage by the insects.

Larvae tended to fall from plants of the genotypes PI 229358 and PI 171451 possibly because lack of feeding stimulants or presence of repellents caused high larval movement and leaf surfaces provided poor footing for the insects.
Photosynthesis and Respiration by Healthy and Beet Yellows Virus‐Infected Sugar Beets (Beta vulgaris L.)1
Authors: Hall A. E. , Loomis R. S.
Published: July 2010

Beet Yellows Virus infection substantially reduced lightsaturated net photosynthesis (Pn) of sugar beets (Beta vulgaris L.) grown outdoors under intense radiation in a warm environment. Smaller Pn reductions were observed with plants grown at moderate irradiances in a growth chamber at both moderate and warm daytime temperatures. Light‐saturated Pn rates for healthy plants were similar in all environments. Photorespiration estimated from low O2 enhancement of Pn was lower in infected plants. Respiration per unit leaf area estimated by CO2 evolution in the dark was slightly greater with infected leaves of outside plants but not with those in the growth chamber. Model simulations of crop assimilation rate predicted that the reduced Pn could cause the substantial reductions in crop growth rate that are often exhibited by virus‐infected plants. The model also predicted that the reductions in leaf area that result from infection may have little effect upon growth rate, providing that infection occurs after the early seedling stage.
Fitness of Heterozygotes in Barley1
Authors: Rasmusson D. C. , Byrne Ignatius
Published: July 2010

The level of dominance at four loci for reproductive fitness was investigated in barley (Hordeum vulgare L,.). Each of the four loci contained a recessive allele, believed to be of spontaneous origin, that is a seedling chlorophyll lethal when homozygous. Populations were established with initial gene frequency of p = .5, and the proportion of normal green to defective seedlings was ascertained in successive selfed generations. Reproductive fitness of the normal homozygote vs the normal heterozygote was indicated in the rate of elimination of the defective allele.

The rate of elimination of the defective allele in ‘Colsess I,’ Colsess II,' ‘Xantha 3,’ and ‘Albino 7’ indicated approximately equal fitness of the normal homozygote and heterozygote, thus suggesting a complete dominance interpretation for reproductive fitness. Small deviations from the dominance model in the direction of partial dominance or over‐dominance were about equally frequent for the Colsess I, Xantha 3, and Albino 7 loci. The allele in Colsess II, decreased in frequency at a rate slightly slower than predicted by the dominance model; however, if over‐dominance was present, it was modest. These data, which support a dominance explanation for reproductive fitness, are in conflict with findings on chlorophyll lethals in corn (Zea mays L.) and with reports on heterozygote advantage for agricultural fitness at the Xantha 3 and Albino 7 loci.
Influence of Windbreaks on Leaf Water Status in Spring Wheat1
Authors: Frank A. B. , Willis W. O.
Published: July 2010

Spring wheat (Triticum aestivum L.) was grown for 2 years with three shelter conditions: (a) exposed, (b) surrounded by a slat barrier, and (c) adjacent to tree shelterbelts. Leaf water potential, stomatal diffusion resistance, and meteorological factors were monitored on selected days. The shelterbelt and slat‐barrier plots received 28 and 69% as much wind as the exposed plot, respectively. Air temperature was slightly higher in the sheltered plots. Vapor pressure deficits were similar for all three conditions. Generally, leaf water potential was consistently lower in the exposed compared to the sheltered plots. The more favorable leaf water potentials were associated with those plots receiving less total wind movement. Stomatal diffusion resistance was less and at a lower leaf water potential for exposed compared to sheltered plants. The data indicate that water relations of wheat plants are more favorable for plant growth and yield when grown with shelter compared to exposed conditions.
Morphological Characteristics of Alfalfa Plants Grown at Several Temperatures1
Authors: Bula R. J.
Published: July 2010

Three alfalfa (Medicago sativa L.) cultivars, representing a range of environmental adaptation, were grown at 20, 25, 30, or 35 C under controlled environmental conditions to determine what effect growing temperature has on growth and development of alfalfa. Stem and leaf weights per plant were highest for plants grown at 25, followed by those grown at 20, 30, and lowest at 35 C. Leaf area per plant was highest for plants grown at 25 C and lowest at 35 C. Plants grown at 20 or 25 C had larger leaves than plants grown at 30 or 35 C. Specific leaf weight was highest for leaves from plants grown at 35 C, but essentially the same at 20, 25, or 30 C. Leaves of plants at 20 or 25 C had larger cells and more intercellular spaces compared to leaves at 35 C.

These data provide a partial basis for explaining the generally lower alfalfa yields during hot, summer periods. Such plants would have less leaf tissue, lower leaf area, and smaller, more densely packed leaf cells than plants growing during the cooler portions of the season. Large cells in the vascular tissue would facilitate translocation of photosynthates and water, and large intercellular spaces in the parenchyma tissue would enhance CO2 diffusion.
Inhibition of Ferricyanide Reduction in Chloroplasts Prepared from Water‐stressed Cotton Leaves1
Authors: Fry Kenneth E.
Published: July 2010

Water stress was applied to cotton (Gossypium hirsutum L.) chloroplasts and leaves by the following treatments: (i) prepared chloroplasts were. placed in assay media different osmotic potentials; (ii) cut shoots were allowed to transpire under illumination; (iii) whole potted plants were held for 5 days without irrigation; and (iv) cell sap was expressed from individual leaves via the xylem in a pressure bomb. These treatments caused a decrease in ferricyanide reduction when isolated chloroplasts were assayed potentiometrically for the Hill reaction. The above treatments caused (i) 1.7%, (ii) 1.4%, (iii) 1.8%, and (iv) 1.9% decrease of initial activity rcspectively per bar of water potential decline. This decrease in activity, which was nearly linear with the degree of stress, occurred from —3 to —30 bars leaf water potential in treatments ], 3, and 4, and from —15 to —30 bars in treatment 2. These results indicate that water stress in the leaf can directly influence the photochemical activity of the chloroplasts.
Effect of Shading Mature Leaves of Alfalfa and Sainfoin Plants on Specific Leaf Weight of Leaves Formed in Sunlight1
Authors: Straley C. S. , Cooper C. S.
Published: July 2010

Light intensity within a canopy may affect the specific leaf weight (SLW, mg/cm2) of new leaves formed. We studied the effect of shading mature and fully expanded leaves of alfalfa (Medicago sativa L.) and sainfoin (Onobrychis viciaefolia Scop.) on SLW of new leaves formed in the sun. Shading of mature leaves of alfalfa and sainfoin plants decreased SLW of new leaves formed. SLW values of alfalfa leaves formed in the sun on plants with old leaves shaded were intermediate between those formed on plants grown under 82% shade or under full sunlight. Alfalfa clones differed significantly in SLW and their order of rank was the same over all treatments. The significance of light intensity within a canopy upon SLW of new leaves formed at the top of the canopy is discussed.
Cyanoglucoside and Hydrolyzing Enzyme in Species Related to Trifolium Repens1
Authors: Gibson Pryce B. , Barnett O. W. , Gillingham J. T.
Published: July 2010

Trifolium repens L. and 16 species closely related to T. repens were tested qualitatively for the presence of cyanoglucoside and the enzyme that releases HCN by hydrolysis of glucoside in damaged leaves. In contrast to T. repens, none of these species contained enzyme in the absence of glucoside. Four species were comprised entirely of plants showing both constituents, one of plants showing glucoside only, and eight of plants showing neither constituent. The remaining three species were alike in that some plants contained glucoside and some did not.
Variation in the Intestinal Gas‐Forming Sugars in Peanut Cultivars1
Authors: Hymowitz T. , Collins F. I. , Panczner J. , Walker W. M.
Published: July 2010

The interaction of intestinal flora with low molecular weight carbohydrates, especially raffinose and stachyose, has been shown to be the primary factor for the flatulence and uncomfortable feeling often experienced by human beings after consuming products containing legume seed meal. There is conflicting evidence, however, concerning the gas‐producing properties of the peanut Arachis hypogaea L.

Seed of 16 cultivars of peanuts were analyzed for protein, oil, total sugar, and individual sugar content. The range in values for protein, oil, total sugar, and sucrose were 27.2 to 33.2, 45.5 to 51.5, 3.2 to 6.4, and 2.7 to 5.6 g per 100 g seed, respectively. Except for ‘Virginia 56R’ and ‘Florigiant,’ the cultivars had raffinose contents of 0.1 g or less per 100 g seed. The cultivars ‘Argentine,’ ‘Early Runner,’ ‘Spancross,’ ‘Tifspan,’ and ‘Virginia Bunch 67’ had stachyose contents of less than 0.1 g per 100 g seed. Based on chemical analyses, these cultivars may be nongas producers. Florigiant, ‘Florunner,’ ‘N.C. 2,’ ‘N.C. 5,’ ‘N.C. 17,’ ‘Starr,’ Virginia 56R, and ‘Virginia 61R’ with 0.4 or 0.5 g stachyose per 100 g seed may be gas producers.
Evaluation of the Genetics of Relative Phosphorus Accumulation by Corn (Zea mays L.) Using Chromosomal Translocations1
Authors: Barber W.D. , Thomas W.I.
Published: July 2010

Reciprocal chromosomal translocations were selected as the genetic tool for an investigation of the genetic control of relative P accumulation by leaves of corn (Zea mays L.). Each of 10 translocation sto~ks was crossed to inbreds Pa 83 and Pa 94, which had been selected as low and high P accumulators, respectively. The translocation stocks were selected so that each corn chromosome would be involved in the translocations of two different stocks. Backcrosses to the inbred parent resulted in 20 progeny sets wherein tests for linkage to interchange points could be made.

Within each backcross progeny set, many of the “semisterile” progeny should be of the F1 genotype at those loci linked to an interchange point; the closer the linkage, the greater the proportion of progeny reflecting the F1 genotype would be. Alternatively, a high proportion of the “normally fertile” progeny should reflect the inbred genotype at these locl. A significant difference between P accumulation, measured as the mean P concentration of the ear leaf blades of progeny in each class, was considered indicative of segregation of at least one genetic locus that influences relative P accumulation. From the results, a minimum of six genetic loci that affect relative P accumulation was postulated. Although the potential effect of each locus could not be evaluated from the data obtained, the total observed segregation accounted for most of the P accumulation difference between inbreds ‘Pa 83’ and ‘Pa 94.’
Diallel Analysis of Correlated Sequential Characters in Durum Wheat1
Authors: Lee J. , Kaltsikes P. J.
Published: July 2010

Diallel regression analysis was applied to four correlated sequential yield component characters in durum wheat (Triticum turgidum L. var. durum): (i) number heads per plant; (ii) number of spikelets per head; (iii) number of grains per spikelet; and (iv) 100‐kernel weight. The untransformed (correlated) data indicated that all of the characters showed predominantly additive genetic effects with some degree of dominance and a general lack of epistatic effects. Analysis of the transformed (uncorrelated) data showed a higher level of dominance and/ or epistasis with a concomitant decrease in the narrowsense heritability estimate for each of the four characters. The phenotypic expression for heads per plant and grains per spikelet was independent of other characters, while that of spikelets per head and 100‐kernd weight was influenced by characters developed previously along the developmental sequence.
Interrelationship of Temperature, Sugar Concentration, and Pollen Parent on Alfalfa Pollen Germination and Tube Growth In vitro1
Authors: Barnes D. K. , Cleveland R. W.
Published: July 2010

In vitro pollen studies with alfalfa (Medicago sativa L.) indicated that both sugar concentrations and temperatures affected pollen germination and pollen‐tube growth. Requirements for pollen germination were less specific than those for pollen‐tube growth. At 18 C 60% of more pollen germination occurred on media containing 7, 14, 21, and 28 g of sugar/100 ml water. At temperatures of 24 and 30 C sugar concentrations of 35 and 42 g also produced germinations greater than 60%. At 36 C germination remained high on sugar concentrations of 14 through 42 g sugar, but declined at lesser concentrations.

In contrast, maximum pollen‐tube length at 18 C was obtained on media with 7 to 14 g sugar. At 24 C media with 7 through 28 g sugar produced maximum pollen‐tube development. At 30 C pollen‐tube growth of some clones was markedly reduced on low sugar media, whereas other clones were less affected. At 36 C very little pollen‐tube growth was observed.

The interaction between sugar concentrations and temperatures suggested to us that alfalfa may have a type of buffering system that allows pollen germination and pollen‐tube growth to occur over a wide range of environments. The data presented in this paper also indicated the existence of temperature‐sensitive genes that may influence pollen‐tube development.
Electrophoretic Identification of Agrostis palustris and Poa pratensis Cultivars1
Authors: Wilkinson J. F. , Beard J. B.
Published: July 2010

The feasibility of creeping bentgrass (Agrostis palustris Huds.) and Kentucky bluegrass (Poa pratensis L.) cultivar identification by acrylamide gel disc electrophoresis was investigated. Fresh leaf protein was extracted at 4 C by grinding in a mortar with a 0.2 M phosphate buffer, pH 7.0 containing 0.1 M sodium ascorbate, 10 mM sodium diethyldithiocarbamate, 0.06 mM 2‐mercaptobenzothiazole, and 1.0 mM disodium ethylenediaminetetraacetate. Tris and unmodified phosphate buffers proved unsuccessful. The protein extract was squeezed from the tissue and centrifuged at 10,000 g for 30 min at 4 C. The supernatant was used for electrophoresis. Electrophoresis was run with a 7% acrylamide gel and a Tris‐glycine electrode buffer, pH 8.3. Protein bands were stained with Coomassie Blue. Six creeping bentgrass cultivars could be individually distinguished. Ten Kentucky bluegrass cultivars were examined. Six could be placed into groups of two, and two could be identified singly, while two showed no characteristic banding.
Pollen Distribution and the Seedset on Triticum aestivum L.1
Authors: Khan Mir N. , Heyne E. G. , Arp Adrian L.
Published: July 2010

Wheat (Triticum aestivum L. em Thell.) pollen dispersion was estimated, utilizing the Kramer‐Collins spore trap and tape on glass rods, in Kansas during 1966, 1968, and 1969. Seedset and yield were recorded in 1966 and 1968 on cytoplasmic male‐sterile (cms) lines. The malesterile sources were cms ‘Bison,’ ‘Shawnee,’ ‘Parker,’ ‘Scout,’ and ‘Aztec,’ with Shawnee B‐line as the pollen source. The male‐sterile lines extended 60 m north to south and 48 m east to west in 1968 and 1969, and 60 m in four directions in 1966.

Pollen distribution, measured continuously in the Kramer‐Collins spore trap, gave a diurnal pattern in 1966 but not in 1968. Cold, cloudy weather in 1968 resulted in a low but nearly continuous pattern throughout the pollinating period. Pollen grains, as measured by tape on glass rods, decreased in numbers as distance from the pollen source increased, but were recorded as far as 60 m from the source. Beyond 3 m, the amount of pollen decreased rapidly.

Seedset and yield patterns were similar to that of pollen number; thus, pollen number and seedset correlated significantly.
Effect of Ethrel on Seasonal Activity of Three Enzymes and Lodging Resistance in Soybeans1
Authors: Blomquist R. V. , Kust C. A. , Schrader L. E.
Published: July 2010

‘Hark,’ ‘Chippewa,’ and ‘Corsoy’ soybeans [Glycine max (L.) Merr.] were grown in field plots in 1969 and 1970. 2‐chloroethylphosphonic acid (Ethrel) at concentrations of 0 to 1000 ppm was applied as a foliar spray when third trifoliolate leaves were 75% expanded. Plants were assayed during the growing season for phenylalanine ammonia lyase (PAL) (4.3.1.a) and peroxidase (1.11.1.7) activity in the stem, and nitrate reductase (NR) (1.6.6.1) activity in the leaves. Acid‐detergent fiber and lignin analyses along with anatomical observations were performed on the stems. Plants were rated for extent of lodging and seed yields were determined. NR activity peaked on July 6, PAL activity peaked during mid‐July, and peroxidase activity peaked in mid‐ to late August. Peroxidase activity increased in response to Ethrel, particularly in the internodes where lodging was first evident in control plants. PAL activity increased in response to Ethrel during the seasonal peak in enzyme activity. Corsoy lodged more than did the other varieties, but lodging was reduced in all varieties. Seed yield was not reduced by Ethrel, indicating that this growth substance may be of use to decrease harvest losses of soybean seed due to lodging.
Yield and Yield Component Heterosis in Avena Hybrids1
Authors: Hathcock B. R. , McDaniel M. E.
Published: July 2010

Appreciable graln‐yield heterosis was observed in several close‐planted oat (Avena spp.) hybrids grown at two locations in Texas in 1968. One hybrid surpassed the best pure‐line entry by more than 35% at each location. Heterosis for grain yield generally was greater than that for individual grain‐yield components. The yield component, seeds per panicle, showed the greatest and most consistent heterotic response. In most crosses, heterosis for grain yield was drastically reduced in the F2.
Effect of Photoperiod and Temperature On Rosette Habit in Safflower1
Authors: Zimmerman L. H.
Published: July 2010

The effect of photoperiod and temperature on duration of rosette habit in safflower was evaluated. Carthamus tinctorius L. and Carthamus flavescens Spreng were grown in the greenhouse at bimonthly planting dates and in controlled environment chambers at different photoperiods and temperatures. In the greenhouse, duration of rosette habit generally increased with decrease in temperature and photoperiod except for the December plantrag. Under high temperature (20/10 C with 10 hr in the light period at 20 C and 14 hr at 10 C regardless of the photoperiod) in controlled environment rooms, rosette habit of both species persisted longer in short photoperiod (10 hr) than in long (14 hr); response proportionately greater in C. tinctorius than in C. flavescens ‐ 68% and 11% longer duration of rosette habits, respectively. These species also responded differently to temperature. In low temperature (15/5 C) and long photoperiod (14 hr), duration of rosette habit of C. tinctorius was 13% longer than under high temperature (20/10 C) and short photoperiod (10 hr), while rosette habits were similar for these treatments in C. flavescens. In both species, genotypes responded differently to the photoperiod‐temperature treatments.
Pollen Production of Fertility Restored Lines of Soft Red Winter Wheats1
Authors: Johnson J. W. , Patterson F. L.
Published: July 2010

Pollen production and seed set were compared for cultivars and derived homozygous pollinator “R” lines with cytoplasm and genetic restorers from Triticum timopheevi. Pollen production and anther extrusion were determined in the laboratory on excised spikes from greenhouse and field‐grown plants. Some restored “R” lines were as good as their parent cultivars for pollen dispersal. In diverse controlled environments restored “R” lines were somewhat more sensitive to temperature and photoperiod than were normal cultivars. Apparently “R” lines developed with T. timopheevi cytoplasm will be satisfactory for most environments.
Effect of Nitrogen and Potassium Fertilization on Organic Acids of Bromus Inermis L. and Dactylis Glomerata L.1
Authors: Barta A. L.
Published: July 2010

The effect of nitrogen and potassium fertilization on the organic acids of Dactylis glomerata L. (orchardgrass) and Bromus inermis L. (bromegrass) was characterized from initiation of spring growth to maturity.

Nitrogen fertilization significantly increased malic, trans‐aconitic, and citric acids in bromegrass and citric acid in orchardgrass, but significantly decreased shikimic and quinic acids in both species. Potassium significantly reduced levels of malic, quinic, and shikimic acids in both species and trans‐aconitic acid in bromegrass. No effect of K on citric acid concentration was noted. Citric, shikimic, and quinic acid concentrations declined with increasing maturity, while the levds of the predominant organic acids (malic and trans‐aconitic) remained constant
Pennisetum Typhoides S. & H. and P. Purpureum Schum. Hybrids for Forage in the Low‐Altitude Humid Tropics1
Authors: Chheda H. R. , Aken'Ova M. E. , Crowder L. V.
Published: July 2010

Dry matter yields of hybrids from Pennisetum typhoides S. & H. v. ‘Maiwa,’ a short‐day photoperiod‐sensitive pearl millet selection from Northern Nigeria, and P. purpureum Schum., elephantgrass, were comparable to the elephantgrass parent in the lowland humid tropics of Nigeria. Under similar conditions hybrids from ‘Tift 23 A,’ a malesterile millet selection from the U.S., and elephantgrass produced significantly less forage than elephant grass. Male‐sterile lines of Maiwa were obtained by transferring the male sterility factors of Tift 23 A.
Diallel Analysis of Leaf Area Heterosis and Relationships to Yield in Maize
Authors: Johnson G. R.
Published: July 2010

Estimates of leaf area index (LAI) at individual leaf positions on 10 commercially adapted maize (Zea mays L.) inbred lines and their diallel set of crosses, and yields of the F1 hybrids, were obtained in order that the mode of inheritance of LAI and the relationship of LAI and distribution of LAI within the canopy to yield could be examined.

Leaf area estimates were obtained from five randomly chosen plants per plot in an experiment in which the parent inbreds and F1 hybrids were arranged in two randomized blocks of one‐row plots, while yields of the F1 hybrids were obtained from an experiment in which the crosses were grown in two‐row plots arranged in a 7 by 7 simple lattice design in two randomized blocks. Row spacing and population in both experiments were 76 cm and 60,000 plants/ha, respectively. Multiple regression models were used to compute analyses of LAI heterotic effects and the relationship of LAI to yield.

The results of the study indicated that: (i) LAI was inherited in a highly heterotic manner; (ii) distribution of leaf area within the canopy accounted for a significant portion of the variation in yield beyond that accounted for by total LAI; and (iii) variation in leaf area near the canopy extremes accounted for most of the yield variation attributable to leaf area distribution.
Inheritance of Coleoptile Length and Culm Length in Crosses Involving Olesen's Dwarf Spring Wheat1
Authors: Hoff J. C. , Kolp B. J. , Bohnenblust K. E.
Published: July 2010

Coleoptile length and culm length inheritance were studied in F1 and F3 populations from spring wheat (Triticum aestivum L.) crosses involving ‘Olesen's Dwarf’ and five tall cultivars with relatively long coleoptiles. In F2 populations studied both characters were quantitatively inherited. Broad‐sense heritability estimates were high for culm length and coleoptile length. Dominance for short culm length was expressed in the O D X ‘Lee’ F1, and coleoptile lengths of the F1 of O D X Lee, O D X ‘10‐VI‐5’, and O D X ‘Chris’ exceeded those of their midparents. Both additive and nonadditive gene action was detected in all crosses except one. Calculated minimum gene numbers were higher for culm length than for coleoptile length. Significant correction correlations were obtained between culm length and coleoptile length; however, coefficient of determination values (r2) were low.
Rye in Malting and Brewing1
Authors: Pomeranz Y. , Standridge N. N. , Schreck J. J. , Goplin E. D.
Published: July 2010

Rye (Secale cereale L.) cultivars grown in 1969 and 1970 in two locations in Nebraska and five locations in North Dakota were malted under laboratory conditions and compared with malted barleys (Hordeum vulgare L.). In addition, the ryes were evaluated in experimental brewing. The rye malts were richer than barley malts in total extract, soluble proteins, and alpha‐amylase. In samples from both states there were varietal effects on rye kernel weight, total extract, and alpha‐amylase; environment affected grain‐N, malt recovery, fine‐coarse grind extract difference, wort color, and amylolytic activity. Increasing grain‐N increased wort‐N and amylolytic activity, and decreased extract. Rye malt darkened beer color, and increased its content of soluble‐N compounds. Use of rye grits (in place of corn (Zea mays L.) grits) in brewing impeded processing of barley malt into beer.
Breeding Behavior of Maize‐Tripsacum Hybrids1
Authors: de Wet J. M. J. , Harlan J. R. , Engle L. M. , Grant C. A.
Published: July 2010

Hybrids bewteen Zea mays L. and octaploid Tripsacum dactyloides (L.) L. are male sterile but female fertile. They reproduce by means of aposporous gametophytic apomixis, or sexually. The 36 Tripsacum chromosomes of these hybrids pair preferentially, while the 10 Zea chromosomes remain as univalents during meiotic prophase and are often excluded from the daughter nuclei. Failure of cytokinesis during the second meiotic division can then give rise to gametes with 36 Tripsacum chromosomes only. These may be fertilized when the hybrids are backcrossed with maize as the pollen parent to give offspring that resemble the parental hybrids in genome constitution. Such sexual gametes apparently never develop parthenogenetically. Occasional pairing between one to four Zea and Tripsacum chromosomes makes intergenome segmental exchange possible. This results in later backcrosses to regular inclusion of Zea chromosomes in the daughter nuclei at the first meiotic division, and functional female gametes with 36 Tripsacum and 2, 4, 6, or 8 Zea chromosomes in homologous pairs are produced.
Influence of Seeding Rate upon Seed and Oil Yield and Their Components in Flax1
Authors: Albrechtsen R. S. , Dybing C. D.
Published: July 2010

Five cultivars of flax (Linum usitatissimum L.) were each seeded at four rates to determine the influence of seeding rate on seed and oil yields, their components, and other plant and seed characteristics. A path coefficient analysis technique was employed to partition yield components into direct and indirect effects to assess the usefulness of yield components as selection criteria in a flax breeding program. Rates of seeding that were used in the study gave 0.8, 1.6, 2.8, and 3.9 viable seeds per cm of row.

Seed yield, oil yield, oil content, iodine value, seed size, seeds per boll, bolls per area, and test weight were not significantly affected by variations in seeding rate. Bolls per plant and height were decreased and maturity was hastened by increased seeding rate. Approximately 85% of the variation in oil yield could be attributed to variation in bolls per area, seeds per boll, seed size, and percent oil. Stand accounted for only an additional 1% of the variation in oil yield.

Path coefficient analysis showed bolls per unit area to be the most important component determining seed and oil yields, both directly and indirectly. Seeds per boll, seed size, and percent oil showed nonsignificant and negative correlations with oil yield, because the positive direct effects they exerted on yield were canceled by negative indirect effects through other components.
Increase in Yield of Bengal Gram (Cicer arietinum L.) by 2,3,5‐Tri‐iodobenzoic Acid
Authors: Sinha S. K. , Ghildiyal M. C.
Published: July 2010

The effect of TIBA (2,3,5‐tri‐iodobenzoic acid) on the yield of Bengal gram (Cicer arictinum L.), a protein‐rich grain legume, was studied. TIBA was sprayed on plants at the time of first flower opening. There was a significant increase in grain yield in two cultivars in pot experiments.
Product Inhibition of Photosynthesis in Alfalfa Leaves as Related to Specific Leaf Weight
Authors: Chatterton N. J.
Published: July 2010

Diurnal changes in SLW (specific leaf weight‐mg dry wt cm−2 leaf area) of recently fully expanded leaves reflect the photosynthate production‐translocation balance within the leaf. Therefore, SLW should increase when synthesis exceeds transport and should decrease when transport exceeds synthesis. SLW had a close negative correlation with NCE (net carbon dioxide exchange rate‐mg CO2 dm−2 hr−1) as measured on attached alfalfa (Medicago sativa L.) leaves. Since maximum NCE coincided with minimum SLW (after about 1 hr illumination) and furthermore, a secondary maximum NCE occurred concomitantly with a secondary minimum SLW (after about 4‐hr illumination) a causal relationship between the changes in NCE and SLW is suggested. The close negative relationship between NCE and SLW is interpreted as additional evidence for a feed‐back inhibition of photosynthesis.
Meiosis and Pollen Viability in Hexaploid Triticale1
Authors: Sapra V. T. , Heyne E. G.
Published: July 2010

Meiosis and pollen viability were studied in three triticale populations, bulk, outcross and pureline. Sporocytes collected at random in these populations showed that the outcross population was less stable cytologically than the bulk and pureline populations. Cytological instability, expressed by number of univalents at metaphase I and occurrence of micronuclei at telophase I and quartet stages, was common. Meiotic index was positively correlated with seedset but not with seed size. Meiotic index was positively correlated with the percentage of normal cells at telophase I but not at metaphase I. Pollen viability varied with lines, populations, locations, and years.
Pollen Germination and Tube Growth after Selfing and Crossing Coronilla varia L1
Authors: Baluch S. J. , Risius M. L. , Cleveland R. W.
Published: July 2010

Crownvetch, Coronilla varia L., is relatively self‐incompatible. Plants selected to represent the full range of self‐fertility of a large sample of C. varia L. ‘Penngift’ were used in greenhouse experiments to locate the site or sites of incompatibility of self‐pollinations. Pollen germination and pollen tube growth in pistils after self‐ and cross‐pollinations were observed employing UV fluorescence microscopy.

Pollen germination on the stigma and pollen tube penetration of the style occurred within the first 12 hours after self‐ and cross‐pollination. Pollen tubes reached ovaries within 24 hours for both types of pollination.

In one experiment, the average number of germinated pollen grains on stigmas was significantly higher after crossing than after selling. However, this relationship between the two types of pollination was not consistent over the plants studied. For most plants, pollen germination on stigmas after cross‐pollination was about twice that after self‐pollination. This suggested that self‐incompatibility existed on the stigma. In the second experiment, using a different pollen source, the average number of germinated pollen grains on the stigma after crossing was not significantly different from that after selfing and the site of incompatibility seemed to be in the style.

Pollen tube behavior in the ovary was the same for selfing and crossing in both experiments. For selfing, less ovules matured as seed than were penetrated by pollen tubes. Thus, both fertilization failure and post‐fertilization ovule abortion could have affected the amount of seed set after selling.

Pollen germination and pollen tube behavior were the same in flowers from excised stems and stems growing on plants.