bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Phytoalexin and Aflatoxin Producing Peanut Seed Culture System
Authors: Basha S. M. , Cole R. J. , Pancholy S. K. 
Published: April 2010

Abstract
An in vitro seed culture system was established to grow peanut seed of different maturities viz. white, yellow, orange, brown and black, using a modified Murashige and Skoog medium. Under this system peanut seed of yellow, orange, brown and black maturity categories grew to maturity as measured by increase in their size and germinability. In vitro cultured seeds produced significant amounts of phytoalexins and were contaminated with aflatoxins following their inoculation with Aspergillus spp. while the noninoculated sterile controls did not produce any phytoalexins. Exposure of seed cultures to water stress using various concentrations of mannitol (0 to 1 M) and polyethylene glycol 8000 (0-30% w/v) caused a significant decrease in their phytoalexin producing ability, and enhanced fungal growth compared to the nonstressed controls. The seeds that were stressed with mannitol and subsequently inoculated with A. flavus and A. parasiticus showed a significant increase in the aflatoxin contamination of stressed seed compared to the unstressed control. This would indicate that in vitro grown seeds responded to water stress similar to the field grown peanuts by loosing their ability to produce phytoalexins and increased susceptibility to aflatoxin contamination. Hence, this system has a potential application in evaluating peanut genotypes for aflatoxin resistance under water stress.
Effect of Application Techniques on Performance of Propiconazole for Peanut Disease Control
Authors: Brenneman T. B. , Sumner H. R. , Chandler L. R. , Hammond J. M. , Culbreath A. K. 
Published: April 2010

Abstract
Propiconazole (Tilt®) was applied to Florunner peanut by injection into irrigation water (chemigation) or as a foliar spray. At rates of 0.12-0.25 kg/ha of propiconazole control of both Rhizoctonia limb rot (Rhizoctonia solani AG-4) and stem rot (Sclerotium rolfsii) was inconsistent. Chemigation resulted in the lowest incidence of stem rot, but the incidence of stem rot was only 26% less than the control. Yields from plots receiving chemigation were greater than expected based on disease ratings, indicating that some effects of the fungicide were not being evaluated. Where foliar sprays of chlorothalonil were applied for late leaf spot (Cercosporidium personatum), supplemental applications of propiconazole via chemigation improved leaf spot control. However, substituting chemigated propiconazole for foliar sprays of chlorothalonil consistently resulted in more severe leaf spot and, in one year, decreased yields. Propiconazole is most effective against leaf spot when applied as a foliar spray, whereas chemigation applications provide optimum efficacy against soilborne pathogens of peanut.
In Vitro Reproductive Development of a Diploid Wild Species, Arachis duranensis1
Authors: Feng Q. L. , Pattee H. E. , Stalker H. T. 
Published: April 2010

Abstract
Embryo abortion at an early stage of reproductive development is a major impediment for introgressing germplasm from wild to cultivated species of Arachis by interspecific hybridization. Ovule and embryo culture techniques have been used to rescue aborting hybrid embryos, but increased efficiency and recovery of very young tissues are still needed. The objective of this study was to induce growth and differentiation of A. duranensis proembryos. Seven-, 10-, and 14-d-old peg tips were cultured on a modified basal medium containing MS and B5 media combinations with 16 combination treatments using three growth regulators—1-naphthaleneacetic acid, gibberellic acid, and 6-benzylaminopurine—each at four levels. The results showed that seeds could be obtained in vitro by peg tip culture of four- to 16-celled proembryos. The favorable concentration ranges of growth regulators for pod formation and embryo development were 0.5-2.0 mg/L NAA, 0.05-0.5 mg/L GA3, and 0.05-0.2 mg/L 6-BAP. Over all three selected ages of pegs, the three best combinations of growth regulators resulted in 4.8, 4.7, and 3.5% pod formation, respectively.
Use of Seed Protein Profiles to Characterize Peanut Cultivars1
Authors: Bianchi-Hall C. M. , Keys R. D. , Stalker H. T. 
Published: April 2010

Abstract
In the last 10 to 15 yr, the development of biotechnology and molecular techniques has allowed great advancements toward the identification of cultivars among plant species. In legumes, the success of cultivar identification depends on the species under investigation, the type and variability of genetic material found in cultivars, and the technology used for investigations. In this study, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to assess diversity of peanut (Arachis hypogaea L.) seed protein profiles. The objectives of this investigation were a) to assess diversity of protein profiles in peanuts for cultivar identification using SDS-PAGE and b) to determine the extent of variability of seed storage proteins (SSP) among samples of cultivars originating from different locations. The first study included 34 cultivars grown at Lewiston, NC and the second one included nine cultivars grown at six locations. The results of both studies indicated that it is possible to differentiate between subspecies but not to associate a particular profile with only one specific cultivar. Within subspecies, cultivars clustered in more than one group and most cultivars that grouped together were genetically related.
Recovery of Primary Transformants of Valencia-type Peanut Using Agrobacterium tumefaciens1
Authors: Cheng Ming , Hsi David C. H. , Phillips Gregory C. 
Published: April 2010

Abstract
Four regenerable seedling explants of peanut cv. New Mexico Valencia A, two different strains of Agrobacterium tumefaciens, and two transformation protocols were used in peanut genetic transformation experiments. The putative transformation-competent cell types were identified by transient expression of the β-glucuronidase (GUS) reporter gene, and were compared to the regeneration-competent cell types identified histologically in the four explant systems. One primary transformant plantlet and two primary transformant shoots were recovered from petiolule-with-blade-attached explants inoculated with Agrobacterium strain CKS (A208:pTi37ASE X pEMZ) following a long cocultivation time on the regeneration medium and using low selection pressure for kanamycin resistance. The leaves of the primary transformants expressed nopaline accumulation used as a marker gene, and the engineered 35S-15kD zein protein coding sequence as determined by western blot. The results from these experiments may be useful for developing reliable methods of genetic transformation for valencia-type peanut.
Evaluation of Virginia-type Peanut Cultivars for Resistance to Southern Corn Rootworm1
Authors: Coffelt T. A. , Herbert D. A. 
Published: April 2010

Abstract
Southern corn rootworm (SCRW) (Diabrotica undecimpunctata howardi Barber) is the most damaging soil insect to peanut (Arachis hypogaea L.) in the Virginia-North Carolina production area. New cultivars and advanced breeding lines have not been evaluated for resistance to SCRW. The objective of this 3-yr study was to evaluate three new cultivars (NC-V 11, VA-C 92R, and Agra Tech VC-1) and an advanced breeding line (VA 861101) for resistance to SCRW. NC 6 and NC 9 were used as resistant and susceptible checks, respectively. Pod damage, yield, market grade, and dollar value were obtained for each plot. Agra Tech VC-1, VA-C 92R, and VA 861101 had less total pod damage from SCRW than NC 9. VA 861101 produced significantly higher yields and value per ha than all cultivars on soil types conducive to SCRW damage. Insecticidetreated plots had significantly higher value per ha and lower total pod damage than untreated plots. Results from this study indicate that VA 861101 may be an acceptable replacement for NC 6. Agra Tech VC-1 is the most resistant of the newly released cultivars, but this is not reflected in higher yields.
Enhancing Techniques for Studying Mitotic Peanut Chromosomes1
Authors: Dhesi J. S. , Stalker H. T. 
Published: April 2010

Abstract
Peanut chromosomes are small and preparations of well-spread, darkly stained mitotic cells can be difficult to obtain. Techniques developed for wheat were adapted to peanut. The results are highly reproducible and many dividing cells with darkly stained chromosomes can usually be observed when root tissues are used for preparation. Applications also can be made for determining ploidy levels and chromosome numbers of plants by using immature leaf tissues. The technique has application for both diploids and polyploids and is suitable for both chromosome counts and karyotyping studies.
Genotype-by-Environment Interaction in Roasted Peanut Attribute1
Authors: Pattee H. E. , Isleib T. G. , Giesbrecht F. G. 
Published: April 2010

Abstract
Although roasted flavor of peanut (Arachis hypogaea L.) seed is an important attribute with respect to consumer acceptance, little is known about the relative influences of cultivar, environment, and their interaction on expression of the trait. From 1986 to 1991, samples of seven peanut cultivars were obtained from peanut research programs representing the three major production areas in the United States. Samples were roasted to a nearly common color, ground into paste, and assessed for roasted flavor and fruity attribute by a trained sensory panel. CIELAB L*a*b* color was also measured for use as a covariate in statistical analysis to adjust for remaining differences in color. Subsets of the data were constructed to be orthogonal for cultivar and environment. Environmental variation was highly significant for all subsets and for the overall data set with variation among years being the largest component. Production regions were not a significant source of variation, but locations within years and regions were significant. Cultivars varied significantly in most cases with the runner cultivars Florunner and Marc I consistently superior in flavor to virginia cultivars Florigiant, NC 7, NC 9, and NC-V 11. There were no significant differences among the virginia cultivars. Pronto, a spanish cultivar, was comparable to the virginia cultivars in flavor. Cultivar-by-environment interaction was significant in the overall data set and in most of the orthogonal subsets. The main component of interaction in the overall set was cultivar-by-location interaction within years and regions. Results were inconsistent in the various subsets with cultivar-by-region interaction being significant only in one subset. Components of variance and standard errors of cultivar mean comparisons estimated from the overall data set indicate that design of field experiments to compare genotypic means should emphasize replication across year-location combinations rather than replication within combinations. For accurate estimation of means, replication across several years is necessary, but for comparison of genotypes, additional locations may be substituted for years.
Early and Late Leaf Spot Resistance and Agronomic Performance of Nineteen Interspecific Derived Peanut Lines1
Authors: Ouedraogo M. , Smith O. D. , Simpson C. E. , Smith D. H. 
Published: April 2010

Abstract
Nineteen selected interspecific peanut lines with resistance to leaf spot [Cercospora arachidicola Hori and/or Cercosporidium personatum (Berk, and Curt.) Deighton] were field tested 3 yr for disease reaction and productivity with and without foliar fungicide protection. Measurements included severity ratings of leaf spot every 2 wk based on the Florida leaf spot disease rating scale, and pod yield. Area under disease progress curves (AUDPC) and pod yield losses were calculated. Differences among the interspecific lines in AUDPC values were significant, and one line had values equal to or lower than that of Southern Runner. One-half of the lines were equal in yield (P=0.01) to Southern Runner. Yields among lines averaged 1 to 50% higher with, as compared to without, chlorothalonil application. Yield losses of individual entries varied significantly from 1 yr to another and incongruous with the AUDPC pattern. Correlations between the AUDPC and yield loss were significant (P=0.01) for the 1989 and 1990, but not for the 1988 data. Results of the study indicate that resistance to both C. arachidicola and personatum were incorporated from the wild species parents into productive, runner-type breeding lines, and that the resistance to personatum was equal to or better than that of Southern Runner. Additional effort will be required to transfer levels of leaf spot resistance observed in the wild species parents into successful cultivars.
Growth Response of Peanut to Field Inoculation with Endomycorrhizal Fungi, Bradyrhizobium, and Supplemental Phosphorus in Texas1
Authors: Taber R. A. , Smith O. D. , Smith D. H. , Segner S. L. , Taber W. R. , Pettit R. E. , Neck J. S. , Rajapakse S. , Harman W. L. 
Published: April 2010

Abstract
Field studies were conducted at four locations in Texas over a two year period to assess the response of five peanut cultivars to inoculation with four species of vesicular-arbuscular endomycorrhizal fungi (VAMF) with or without Bradyrhizobium sp., and Bradyrhizobium alone. Supplemental phosphorus treatments were also included. Replicated treatments were superimposed upon indigenous microflora in five nonfumigated field plots. Soil phosphorus (up to 50 ppm) did not necessarily stimulate peanut growth nor negate growth stimulation by mycorrhizal fungi. VAMF species differed in their effectiveness for increasing peanut growth characteristics such as root, shoot, and pod weights but did not affect peanut yield. Cultivars also responded differently to inoculation. Shoot and root weights of inoculated plants increased more rapidly than the controls early in the growing season. Increased dry pod weights were obtained at two locations; however, yields of peanut from all treatments at harvest were statistically similar. The value of fieldinoculation of peanut with vesicular-arbuscular endomycorrhizal fungi used in this research is discussed.
Effects of Belt Screen Operational Settings on Separations of Farmers Stock Peanut Materials
Authors: Blankenship P. D. , Davidson J. I. 
Published: April 2010

Abstract
The effects of varying belt screen operational parameters on separating farmers stock peanuts (cv. Florunner), loose shelled kernels (LSK), and foreign materials (FM) were evaluated. The operational parameters evaluated were four screen deck lengths (40.6, 81.3, 121.9, and 162.6 cm); four belt spacings (0.87, 0.95, 1.03, and 1.11 cm); four belt speeds (81.3, 91.4, 101.6, and 111.8 cm/sec); and four feed rates (0.45, 0.91, 1.36, and 1.81 t/hr). The amount of materials falling through the screen varied directly with screen deck length and belt spacing. Screen deck length had the greatest effect on the amount of LSK, total FM, sticks from FM, dirt from FM, and rocks from FM falling through the screen. Belt speeds and material feed rates had less effect on the separations made than screen deck length and belt spacing.
Photosynthetic and Respiratory Characteristics of Peanut Cultivars Adapted to Varying Night Temperatures1
Authors: Bell M. J. , Tollenaar M. , Michaels T. E. 
Published: April 2010

Abstract
Relatively mild night temperatures can reduce leaf carbon dioxide exchange rates (CER) and dry matter (DM) accumulation in peanut (Arachis hypogaea L.). To investigate differences among cultivars in response to long-term exposure to a range of night temperatures, three peanut cultivars (OAC Ruby, Chico, and Early Bunch) with known differences in chilling sensitivity were grown in controlled-environment cabinets at the University of Guelph, Ontario. Effects of long-term exposure to night temperatures from 9 to 20 C were assessed in terms of leaflet and whole plant CER, DM accumulation, and phenological development. Effects of night temperature on rate of phenological development and DM accumulation were consistent with differences in accumulation of degree-days. Cultivars did not differ in daytime leaf CER response to all night temperatures except 9 C, at which CER for OAC Ruby was higher than for Early Bunch or Chico. CER in the 9 C treatment was 92% of the CER at 20 C for OAC Ruby and 80% for Early Bunch and Chico. Continuous exposure to night temperatures of 10C reduced CER sensitivity to low daytime temperature in OAC Ruby, but Early Bunch was unaffected. Specific respiration rates were higher for plants of OAC Ruby than Early Bunch in the 10 C treatment, with indications that these differences were due to increased maintenance requirements. The ability of OAC Ruby to adapt to cool-night conditions may have a significant impact on crop performance in cooler environments.
Simulated Air Flow Rate Effects on Drying Times and Costs for Conventional and Recirculating Peanut Drying Facilities1
Authors: Chai L. , Young J. H. 
Published: April 2010

Abstract
In conventional nonrecirculating peanut drying systems, an air flow rate of 10 m3/min-m3 is recommended. Drying systems utilizing air recirculation need not consider the inefficiency associated with unsaturated air exiting the system, since the extra drying capacity of the air will eventually be utilized. As a result, the air flow rate recommendation for recirculation type drying systems needs to be reexamined. In this study, two computer models were modified to simulate the peanut drying process in a solar-assisted partial air recirculation drying system and a conventional drying system, respectively. The weather data from the 1992 drying season at Lewiston, NC and the parameters of both facilities were used as the input data for the models. Air flow rates of 5, 7.5, 10, 12.5, 15, 17.5, 20, and 22.5 m3/min-m3 were examined. The simulation results showed that the effect of air flow rate on drying times and costs in a solar-assisted partial air recirculation peanut drying facility was significant. When the air flow rate was increased, the seasonal drying capacity, the electrical and fuel consumption, and total or specific drying cost increased as well. On the other hand, drying time for each wagon decreased and total energy consumption remained relatively constant.
Evaluation of Six Landrace Accessions of Arachis hypogaea ssp. hypogaea var. hirsuta Kohler. I. Descriptive and Sensory1
Authors: Pattee H. E. , Williams D. E. , Sanchez-Dominguez S. , Giesbrecht F. G. 
Published: April 2010

Abstract
The “hirsuta” peanut (Arachis hypogaea ssp. hypogaea var. hirsuta Kohler) is severely under-represented in germplasm collections throughout the world. Reports on heritability of the roasted peanut and sweet flavor attributes suggest that it would be important to quantify the levels of these attributes in hirsuta peanut to determine if these landraces could provide a genetically diverse source for the improvement of roasted peanut flavor. Recent collection explorations in Mexico provided an opportunity to obtain six hirsuta landrace accessions which could be used to make such an evaluation. Descriptive sensory analysis of the roasted samples showed no distinct flavor characteristic differences between hirsuta samples and U.S. cultivars. Significantly higher intensities of the roasted peanut attribute were not present in any of the hirsuta samples when compared to the U.S. cultivars. Significantly higher intensities of the sweet attribute were present in some of the hirsuta landraces compared to the U.S. cultivars, and the sweet intensity difference between NC 7 and Florunner controls was significant. This higher intensity of sweetness may account for the preference of the hirsuta peanut by the Mexican locals.
Relationship of Hull Mesocarp Color to Seed Germination and Vigor in Large-Seeded Virginia-Type Peanuts
Authors: Spears J. F. , Sullivan G. A. 
Published: April 2010

Abstract
Classification of peanuts (Arachis hypogaea L.) based on pod mesocarp color has become a popular means of estimating maturity of runner peanuts. This study was initiated to determine if the hull mesocarp color is related to seed maturity of virginia-type peanuts and to evaluate changes in quality as seed mature. Cultivars NC 7 and NC 9 peanuts were harvested by hand in 1990, 1991, and 1992. Pods were separated according to mesocarp color. Seed moisture content and dry weight within a maturity class varied with cultivar and production year. Germination of NC 7 seed grown in 1990 and 1992 increased as seed approached maturity. Immature NC 9 seed grown in 1991 and 1992 had substantially lower germination than seed from mature pods. There was no increase in germination during maturation of NC 7 seed harvested in 1991 or NC 9 from 1990. Seed leakage during imbibition, measured by electrical conductivity, decreased as seed matured. The lowest leakage levels occurred when seed had reached physiological maturity. Germination following accelerated aging (AA) increased as seed matured. Maximum AA germination of NC 7 occurred when seed had reached 77, 84, and 100% of their final dry weight in 1990, 1991, and 1992, respectively. NC 9 seed achieved maximum germination following AA after the seed amassed at least 90% of their final dry weight.
Ancestral Contributions to Roasted Peanut Attribute1
Authors: Isleib T. G. , Pattee H. E. , Giesbrecht F. G. 
Published: April 2010

Abstract
Estimates of broad-sense heritability for roasted flavor attribute of peanut (Arachis hypogaea L.) range from 9 to 24% on a single-plot basis. Response to selection is determined by the narrow-sense heritability, calculated from estimates of additive genetic variance which are not available for this trait. One way to assess the additive component of genetic variation is to determine how much of the total phenotypic variation can be predicted from genetic contributions of ancestors of the individuals measured. From 1986 to 1991, samples of 128 peanut cultivars and breeding lines were obtained from peanut research programs representing the three major production areas in the U.S. Samples were roasted to a nearly common color, ground into paste, and assessed for roasted flavor and fruity attribute by a trained sensory panel. CIELAB L* color was also measured for use as a covariate in statistical analysis to adjust for small differences in color. The sum of squares associated with the 128 genotypes accounted for 11% of the total phenotypic variation. Ancestry of the lines was traced back to 47 progenitors for which no further pedigree information was available. Eight progenitors made ancestral contributions that were linearly dependent on the other 39. Ancestral effects accounted for 53% of the genotypic variation, i.e., 6% of the phenotypic variation. Despite shortcomings of this 6% figure as an estimate of narrow-sense heritability for roasted flavor, no other estimates are extant. The residual (nonadditive) variation among genotypes after accounting for ancestral (additive) effects was highly significant. Multiple regression model-building techniques were used to identify 13 ancestors exerting significant effects on roasted flavor. Jenkins Jumbo, F231 (a cross of Dixie Giant with Small White Spanish 3x-2), and Improved Spanish 2B were the only ancestors among the 13 that were common to 40 or more of the 128 lines tested. Jenkins Jumbo was the single most important ancestor, exerting a negative effect on flavor (b = −1.25±0.19). Its progeny would be expected to have roast flavor scores reduced by |b|/2 = 0.62 units and grandprogeny by |b|/4 = 0.31 units. All but four of the 13 ancestors deemed important had deleterious effects on flavor.