bluuebunny/crossref_metadata_2025_split huggingface dataset:
The isomorphism relation between tree-automatic Structures
Authors: Finkel Olivier , Todorčević Stevo 
Published: April 2010

Abstract
An ω-tree-automatic structure is a relational structure whose domain and relations are accepted by Muller or Rabin tree automata. We investigate in this paper the isomorphism problem for ω-tree-automatic structures. We prove first that the isomorphism relation for ω-tree-automatic boolean algebras (respectively, partial orders, rings, commutative rings, non commutative rings, non commutative groups, nilpotent groups of class n ≥ 2) is not determined by the axiomatic system ZFC. Then we prove that the isomorphism problem for ω-tree-automatic boolean algebras (respectively, partial orders, rings, commutative rings, non commutative rings, non commutative groups, nilpotent groups of class n ≥ 2) is neither a Σ21-set nor a Π21-set.
End-of-Row Effects on Peanut Yield Tests1
Authors: Smith O. D. , Simpson C. E. , Howard E. R. 
Published: April 2010

Abstract
Peanut (Arachis hypogaea L.) yield test plots are often trimmed to standard row lengths early in the growing season. This might bias selection if cultivars differ in end-of-row effects. Terminal, sub-terminal, and center row sections of 2-row plots 5 m in length were harvested separately to ascertain relative end-of-row competition effects. Data were collected on two cultivars each of Spanish, runner, and Virginia market types from irrigated and non-irrigated yield tests at each of two locations for two years. Significant end-of-row effects were observed for all cultivars with the greater effect on the Virginia and runner cultivars in non-irrigated tests. Row section × location, irrigation, and market type interactions were significant (P = .0001) but the cultivar within market type × row section interaction was not significant (P = .05) when averaged over tests. Yield component analyses from two tests indicated that higher unit area yields of terminal compared to center row segments resulted from increased pod numbers. Pod and 100-seed weight of mature, two-segmented pods from terminal row sections were less than for center-of-row sections. Disproportionate end-of-row effects among the cultivars on total row yield were not sufficient in this test to cause significant selection misclassifications, if comparisons are made within Spanish and Virginia botanical types.
Effectiveness of Stratified Mass Selection for Yield in Intrasubspecific and Intersubspecific Crosses of Peanut1
Authors: Holley R. N. , Wynne J. C. 
Published: April 2010

Abstract
Methods of broadening the genetic base of the peanut (Arachis hypogaea L.) generally involve crosses of exotic germplasm with locally adapted cultivars. Broadening the genetic base effectively requires the evaluation of a large number of crosses and lines within crosses. Mass selection within a cross in early generation, as opposed to single seed descent or bulk breeding methods, eliminates many undesirable segregates from crosses of exotic with adapted germplasm. In this study five plant introductions, representing different levels of diversity, were crossed with an adapted Virginia (ssp. hypogaea var. hypogaea) breeding line. Twelve high and 12 low yielding plants in the F2 generation of each cross were selected with a high and low selection being made from among 10 plants grown in sixteen 12-plant rows. The selected material was increased and evaluated in F4 generation yield trials at two locations. Stratified mass selection for higher seed yield was effective for both intersubspecific crosses but was only effective for one of the three intrasubspecific crosses. Confounding effects of meat content with seed yield and the small number of F2 plants evaluated may be partially responsible for the lack of effective selection for two of the intrasubspecific crosses. Selection for higher seed yield separated the F2 plants into two groups for meat content with the selections for high seed yield having higher meat content. However, the high and low selections, when evaluated in the F4 generation, were not different for meat content except for one intrasubspecific cross.
Importance of Seed Transmission in The Spread of Cylindrocladium Crotalariae1
Authors: Porter D. Morris , Mozingo R. Walton 
Published: April 2010

Abstract
Cylindrocladium crotalariae, which causes Cylindrocladium black rot (CBR) of peanut (Arachis hypogaea), can be isolated at a low frequency from nondamaged peanut seed (seed size ≥6.4 × 25.4 mm slotted screen) not treated with a seed protectant fungicide. Peanut seed obtained from peanut fields in Suffolk, VA, and Martin County, NC, where CBR was severe in 1985 were infected at a frequency of 1.5% and 1.4%, respectively. Cylindrocladium crotalariae was isolated at twice the frequency from pieces of seed than from whole seed. However, C. crotalariae was not isolated from seed treated for 2 weeks with a seed protectant (DCNA + captan). The fungus was not isolated from seed devoid of testae or seed embryos, but was isolated from seed testae at a frequency of 0.4%. Discolored seed (≥6.4 × 25.4 mm) were infected at a frequency of 7.9%, but following seed treatment, the isolation frequency dropped to zero. Discolored seed measuring &lt; 6.4 × 25.4 mm were infected with C. crotalariae at a frequency often exceeding 10%.
Bidirectional Selection for Nitrogenase Activity and Shoot Dry Weight Among Late Generation Progenies of a Virginia x Spanish Peanut Cross1
Authors: Arrendell S. , Wynne J. C. , Elkan G. H. , Schneeweis T. J. 
Published: April 2010

Abstract
Improvement of the host contribution to nitrogen fixation has been proposed as a method of increasing nitrogen fixation. Significant variability and generally high broad-sense heritability estimates (.60 ± .27 to .82 ± .26 for nitrogenase activity and .53 ± .29 to .85 ± .26 for shoot dry weight) have been reported for F2-derived families from a cross between the Virginia (Arachis hypogaea L. ssp. hypogaea var. hypogaea) cultivar NC 6 and the Spanish (ssp. fastigiata Waldron vulgaris Harz.) breeding line 922, indicating selection for increased nigtogen fixation should be effective in this population. Lines from this population were chosen randomly from F2-derived families selected for high and low nitrogenase activity and high and low shoot dry weight after evaluation at three dates and two locations in each of 2 years (F5 and F6 generations). This study's objectives were to evaluate the N2-fixing ability of the selected lines and to evaluate the association between plant growth habit and N2 fixation. Twenty-four lines in each of the four selection groups and the parents, NC 6 and 922, were evaluated at two sampling dates and two locations. Mean nitrogenase activity of lines selected for increased nitrogenase activity was significantly greater than the mean of the lines selected for low nitrogenase activity. Improved nitrogenase activity was associated with increased fruit weight. The fruit weight mean of the group selected for increased fruit weight. The fruit weight mean of the group selected for increased nitrogenase activity was 39% greater than the mean of the group selected for low nitrogenase activity. Mean shoot dry weight of lines selected for increased shoot dry weight was significantly greater than the mean of the lines selected for low shoot dry weight; however, the fruit weight means of these two groups did not differ.
It was hypothesized that selection for increased N2 fixation in a population derived from a cross between Virginia and Spanish types would eliminate genotypes with Spanish growth habit. Groups selected for high nitrogenase activity and for high shoot dry weight had longer and wider leaflets, longer cotyledonary laterals and greater main stem height than did their respective low selection groups. However, these traits chosen to characterize plant growth habit were inadequate in discriminating parental growth habits. Consequently, the data neither substantiated nor refuted the hypothesis.
A Comprehensive Breeding Procedure Utilizing Recurrent Selection for Peanuts1
Authors: Monteverde-Penso E. , Wynne J. C. , Isleib T. G. , Mozingo R. W. 
Published: April 2010

Abstract
A comprehensive breeding procedure for peanut (Arachis hypogaea L.) consisting of three stages — till development of a genetically broad-based virginia-type population, recurrent selection without extensive crossing for continued population improvement, and isolation of pure lines from high yielding families at each cycle of selection was initiated in 1974. Forty S1 families in S3 generation were selected from each cycle of selection. Only five families from cycle 0 outyielded the check cultivar. Florigiant, whereas yield of all selected families from the next two cycles exceeded the yield of Florigiant. Pure lines isolated from high yielding cycle 0 families have yielded more than Florigiant in advanced yield trials. Use of this procedure provides a systematic approach in developing higher yielding peanut cultivars with a broad genetic base.
Interference of Silverleaf Nightshade (Solanum elaeagnifolium) on Spanish Peanuts (Arachis hypogaea)1
Authors: Hackett N. M. , Murray D. S. , Weeks D. L. 
Published: April 2010

Abstract
Interference of silverleaf nightshade (Solanum elaeagnifolium Cav.) with Pronto spanish peanuts (Arachis hypogaea L.) was evaluated from 1981 through 1983 in a natural occurring weed population. Treatments consisted of weed-free maintenance or weed interference for 0, 4, 8, 12 weeks and for the full season. Silverleaf nightshade stems were counted as a measure of weed regrowth in treatments maintained weed free for 0, 4, and 8 weeks. Contamination of the harvested in-shell peanuts by silverleaf nightshade berries was determined by counting the number of berries passing through the peanut combine. In-shell peanut yields were reduced by an average of 17% when silverleaf nightshade was allowed to interfere with the crop for 4 weeks. Further yield reductions of 53, 66, and 66% were observed in treatments where interference occurred for 8 and 12 weeks and for the full-season, respectively. Regression analysis conducted on yield data of individual years predicts that each week of weed-free maintenance after crop emergence results in an average of 33 to 38 kg/ha yield increase above the unweeded control. Conversely, analyses of yield data averaged over all years indicated that for each week of weed interference there would be approximately a 103 kg/ha decrease in in-shell yield compared to the weed-free control. When yield data were converted to percent of yield of weed-free controls, there was no interaction among years. Regression analysis of the converted data predicts that for each week of weed-free maintenance after crop emergence there would be a 3.7% yield increase compared to the unweeded control and that for each week of weed interference there would be a corresponding yield loss of 4.5%. Silverleaf nightshade stem counts per plot were reduced an average of 18 and 36 percent for treatments maintained weed free for 4 and 8 weeks, respectively. In 1982 analysis of fruit contamination indicated a significant difference between full-season interference and weed-free maintenance for 4 or more weeks. Differences in fruit contamination between 4, 8, and 12 weeks of weed-free maintenance were not significant. In the second year no differences in fruit contamination were observed between the weedy check and the other treatments; however, fruit production after 4 weeks of weed-free maintenance was significantly higher than after 8 and 12 weeks of weed-free maintenance. Peanut quality, disregarding contamination by silverleaf nightshade berries, was not affected by weed interference.
Selection Indices for Simultaneous Selection for Pod Yield and Leafspot Resistance in Peanut (Arachis hypogaea L.)1
Authors: Iroume R. N. , Knauft D. A. 
Published: April 2010

Abstract
The objective of this study was to investigate the possibility of index selection for pod yield and leafspot resistance, causal organisms Cercospora arachidicola Hori and Cercosporidium personatum (Berk. and Curt.) Deighton, in peanut (Arachis hypogaea L.). Eleven crosses were evaluated in the S1 and S2 generations under natural disease pressure for pod yield and disease reaction. Leafspot severity was measured by leaf necrotic area and defoliation. Variances for each trait and covariances between traits were estimated by progeny analysis. Economic weights assigned to the different characters were derived as the ratio of the pod yield for a genotype to the theoretical pod yield gain from leafspot resistance. Indices were constructed and their efficiency both as predictor of the breeding value and relative to individual selection for either trait was evaluated. Index selection for increased pod yield and reduced leafspot susceptibility was between 87% and 100% as efficient as direct selection for either trait. Combining several leafspot severity readings with pod yield did not improve the efficiency of the index. Fourteen to 17% of the breeding value of the population was accounted for by the traits combined in various indices. This indicated that there is potential for improvement of these indices.
Calcium, Nitrogen, and Rhizobium Effects on Arachis Hypogaea L. Valencia C
Authors: Taylor Robert G. , Moshrefi Karim 
Published: April 2010

Abstract
Nutritional needs of numerous plants (Arachis hypogaea L.) cultivars have been extensively examined, especially responses to N fertilizer, Ca availability in the soil solution, and the use of rhizobium soil inoculum. The nutritional effects of these three factors and their interactions on particular processes at various stages of growth and development of the plant were examined. Three levels of Ca and four N treatments were tested in a greenhouse on two sets of the Valencia C peanut cultivar, one receiving a soil inoculum and the other did not. Nutritional and soil inoculum treatment effects on primary stalk length, flower production, peg and pod development, and nodulation occurrence were statistically examined.
Calcium and N were found to strongly, and independently, influence plant nodulation. Soil inoculation had no influence on flowering, peg or pod production. However, both Ca and N independently influenced these processes. Synergism between Ca and N appeared to influence peg development but not pod development. Additionally, the presence of rhizobium inoculum did not increase pod development. The presence of rhizobium soil inoculum which promoted nodule formation, was not closely related to fruit production but was related to the growth of the aerial portion of the plant.
Effect of Pod Maturity and Plant Age on Pod and Seed Size Distributions of Florunner Peanuts
Authors: Williams E. Jay , Ware Glenn O. , Lai Jia-Yee , Drexler J. Stanley 
Published: April 2010

Abstract
Florunner peanut pods (Arachis hypogaea L.) were sampled at nine weekly intervals from 92 to 148 days after planting (DAP) in crop year 1979. The fresh pods were divided into six maturity categories according to the color and structure of the mesocarp. After drying, individual pods and seed for each maturity class and date were sized over a series of screen slots conforming to official grade standards. The cumulative distribution function (CDF) for the logistic distribution was used to quantify the cumulative percentage by weight of pods and seed which rode a designated screen. The parameters of the logistic CDF were regressed separately by maturity class as functions of plant age. These relationships provide a mathematical approach for a better understanding of the influence of pod maturity and plant age on pod and seed sizes.
Effects of Modification of the Plant Canopy Environment on Sclerotinia Blight of Peanut
Authors: Dow R. L. , Powell N. L. , Porter D. M. 
Published: April 2010

Abstract
The development of Sclerotinia blight, caused by Sclerotinia minor Jagger under various environmental conditions, was studied in field plots of peanuts (Arachis hypogaea L.). The peanut plant canopy was modified to produce desired environmental parameters. The modifications included the thinning of canopy foliage to allow air circulation that would decrease canopy humidity and the addition of water-filled troughs under an unthinned canopy that would increase humidity. Canopy relative humidity and soil moisture under the canopy was decreased by canopy thinning. Following infection by S. minor, the number of infection foci and disease development was reduced in the thinned canopy; however, thinning also reduced pod yield. Disease development was not increased, nor was yield affected by the addition of the water-filled troughs which increased humidity levels in the canopy. Soil moisture and canopy light interception were important variables in multiple linear regression models for the disease severity index and longest lesion length in the thinned and unthinned-trough plots.
Heterosis and Combining Ability Studies and Relationship Among Fruit and Seed Characters in Peanut1
Authors: Dwivedi S. L. , Thendapani K. , Nigam S. N. 
Published: April 2010

Abstract
F1 progenies from an 8 × 8 full diallel cross were studied for the inheritance of fruit yield and fruit and seed characters which are important in peanut (Arachis hypogaea L.) quality breeding. Substantial genetic variaton was observed for most characters among parents and crosses. Presence of significant heterotic crosses for several characters was an indication of genetic diversity present among the parental lines. Whereas fruit and seed traits were controlled largely by additive genetic effects and fruits/plant and fruit weight/plant by nonadditive genetic effects, for shelling percentage both were equally important. Estimates of general combining ability (gca) for ICGV 86564 was best for various fruit and seed traits. Other genotypes with good gca were ICG 2379 and ICG 3043 for fruit weight/plant and ICGV 87123 for shelling percentage. ICG 4906, ICG 7360, and ICGV 86564 showed significant maternal effects for various traits. Significant maternal interaction effect was evident for more than six traits in six crosses. A positive association among fruit and seed traits, and of fruit weight/plant with fruit number and with fruit/seed length and width should result in progenies with larger fruit/seed size coupled with increased yields.
Effects of Cleaning Peanuts on Insect Damage, Insect Population Growth and Insecticide Efficacy1
Authors: Arthuf Frank H. 
Published: April 2010

Abstract
Farmers stock peanuts were either cleaned by removing foreign material and reducing loose-shell kernels (LSK) or left uncleaned before being treated with insecticides, stored, and artificially infested with several stored peanut insect pest species. The uncleaned peanuts contained only 2.8% foreign material. After 8 and 10 months the percentage of insect-damaged cracked pod kernels was 1.7 to 3.4 X greater in cleaned treated peanuts than in uncleaned treated peanuts, and there was a direct inverse relationship between the number of LSK and the percentage of damaged cracked pod kernels. After 8 and 10 months, the percentage of damaged cracked pod kernels in each class of peanuts, cleaned and uncleaned, was 1.6-5.7 X greater in peanuts treated with 52 ppm malathion than in peanuts treated with either 25 ppm chlorpyrifos-methyl or 25 ppm chlorpyrifos-methyl + 4 ppm methoprene. A significant difference in insect populations between cleaned and uncleaned peanuts occurred in untreated peanuts after two months, when almond moth and Indianmeal moth populations were greater in uncleaned peanuts. Thus, even a small amount of foreign material may provide a hospitable habitat for insect population growth. There were no significant differences in either insect damage or insect populations between chlorpyrifos-methyl and chlorpyrifos-methyl + methoprene.
Parasitism of Rust, Early and Late Leafspot Pathogens of Peanut by Verticillium Lecanii
Authors: Subrahmanyam P. , Reddy P. M. , McDonald D. 
Published: April 2010

Abstract
Verticillium lecanii was found parasitizing rust, early and late leafspot pathogens of peanut in the glasshouse at ICRISAT Center and in fanners' fields in the Indian States of Andhra Pradesh, Karnataka and Tamil Nadu. In inoculation experiments, there was a significant reduction in the extent of rust and late leafspot development on peanut leaves inoculated with V. lecanii. Receptivity and percentage leaf area damage of rust and late leafspot were reduced when inoculated with V. lecanii. The potential use of V. lecanii in biological control of rust and leafspot diseases of peanut is discussed.
Evaluation of Ammonium Bicarbonate for Control of Soilborne Peanut Pathogens
Authors: Brenneman T. B. , Csinos A. S. , Phipps P. M. 
Published: April 2010

Abstract
Ammonium bicarbonate was evaluated for efficacy against southern stem rot and Sclerotinia blight of peanut in Georgia and Virginia, respectively. In vitro studies indicated the material provided little inhibition of mycelial growth by Sclerotinia minor and Sclerotium rolfsii, and negligible inhibition of mycelial growth of Rhizoctonia solani AG-4. However, ammonium bicarbonate did effectively inhibit formation of sclerotia by S. rolfsii in vitro. In the field, it was phytotoxic when applied as a granule or as a foliar spray and in general was not effective in controlling disease or increasing pod yield.
A Note on the Effect of Soil Reaction and Zinc Concentration on Peanut Tissue Zinc1
Authors: Cox F. R. 
Published: April 2010

Abstract
Zinc uptake by peanuts (Arachis hypogaea L.) is affected by both soil pH and extractable Zn concentration, but the combined effect of these two factors is not well defined. An experiment with lime rates was conducted using NC7 peanuts that showed an exponential decrease in leaf Zn as the soil pH increased from 4.3 to 6.1. The decrease was very rapid when the soil was more acid, and less rapid as acidity decreased. Plant Zn was also shown to increase quadratically with increasing soil Zn with a data set from Georgia. These two relationships were combined, assuming no interaction exists, to be able to predict peanut tissue Zn as a function of both soil pH and extractable Zn with either the Mehlich-1 or Mehlich-3 solutions. Equations are presented that conform closely with currently assumed values of critical deficient and toxic concentrations in the tissue and soil for peanuts. These should be especially helpful in predicting potential toxicities over a range of pH and soil Zn levels.
Nontarget Effects of Soil-Applied Chlorpyrifos on Defoliating Pests and Arthropod Predators in Peanut1
Authors: Funderburk J. E. , Braxton L. B. , Lynch R. E. 
Published: April 2010

Abstract
Studies determined the effects of granular chlorpyrifos on densities of nontarget arthropods in peanuts. A portion of several commercial fields was treated during the early pod stage of peanut growth in 1987 and 1988; then, densities of defoliating pests and arthropod predators were estimated weekly. Populations of Helicoverpa spp. were significantly increased in 1987 by chlorpyrifos application, but were not significantly affected in 1988. Densities of the velvetbean caterpillar, Anticarsia gemmatalis Hubner, were low on most sample dates. On dates when densities were great, populations were directly suppressed by chlorpyrifos application. Densities of the fall armyworm, Spodoptera frugiperda (J. E. Smith), were always low, and were not affected by chlorpyrifos application. Arthropod predators sampled included the red imported fire ant, Solenopsis invicta Buren; spiders (Aranaea: Araneidae); ground beetles (Coleoptera: Carabidae); earwigs (Dermaptera: Labiduridae); damsel bugs (Hemiptera: Nabidae); and bigeyed bugs (Hemiptera: Lygaeidae). Densities of spiders were significantly decreased by chlorpyrifos application. The other predators were not significantly affected. These results demonstrate that chlorpyrifos application results in nontarget effects on defoliating pest populations. Treated fields should be scouted regularly, because such fields may have an increased potential for outbreaks of some defoliating pests.