bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inheritance of Stem Color and Non-Nodulation in Peanut1
Authors: Essomba N. B. , Coffelt T. A. , Branch W. D. , Van Scoyoc S. W. 
Published: April 2010

Abstract
Extra-nuclear factors have been reported in peanut (Arachts hypogaea L.) for many traits including growth habit, stipule shape, pod constriction, resistance to leafspot disease, and calcium concentration. However, the role of extra-nuclear factors with the inheritance of many other peanut traits remains to be ascertained. The objective of this study was to determine the inheritance of stem color and non-nodulation, and whether their inheritance is influenced by extra-nuclear factors. The study was conducted on the F1 and F2 progenies obtained from a modified diallel design with two A. hypogaea genotypes, Argentine and T2442, and one A. monticola Krap. et Rig. genotype, as parents. Two plant parts (main and lateral stems) were visually classified for stem color (purple, mixed, or green). Plants graded as green-green, mixed-green, or mixed-mixed were grouped as green and all others as purple for genetic analyses. Plants were classified as non-nodulatingif symptoms of N deficiency were observed. Distribution of data for stem color was bimodal, supporting the grouping of data into two phenotypic classes (green and purple). The F2 generation fit ratios of 1 green: 3 purple, 6 green: 10 purple, 9 green: 7 purple, 11 green: 5 purple, or 15 green: 1 purple depending on the parents. These results indicate that a) stem color may be determined by two sets of genes of which the first one may be responsible for purple pigmentation and the second one for green pigmentation, b) these two gene sets, comprising, respectively, one and two loci for purple and green pigmentations, may have epistatic relationships, c) extra-nuclear factors may function as alleles to nuclear genes responsible for stem color, and d) extra-nuclear factors may induce or modify relationships between traits when they interfere with nuclear genes determining these traits. In the F2 of crosses with T2442 as one parent and either A. monticola or Argentine as the other, ratios of 57 nodulating: 7 non-nodulatmg plants and 54 nodulating: 10 non-nodulating plants were observed. These results indicate that a) non-nodulation trait may be determined by three independent non-duplicate genes and b) at least two homozygous recessive loci are required in a genotype for non-nodulation. The following genotypes are proposed for the three parents:
A. monticola: Ps1sPs 1gs1gs1 gs2gs2; N3N3 N4N4 N5N5
Argentine: gs1gs1 Gs1Gs1 gs2gs2; N3N3 N4N4 N5N5
T2442: ps1ps1 gs1gs1 Gs2Gs2; n3n3 n4n4 n5n5
Foliar Penetration and Phytotoxicity of Paraquat as Influenced by Peanut Cultivar1
Authors: Wehtje G. , Wilcut J. W. , McGuire J. A. , Hicks T. V. 
Published: April 2010

Abstract
Field studies were conducted over a three year period to examine the sensitivity of four peanut (Arachis hypogaea L.) cultivars (Florunner, Sunrunner, Southern runner, and NC 7) to foliar applications of paraquat (1, 1′-dimethyl-4, 4′-bipyridinium ion). Treatments included an untreated control and four herbicide treatments: paraquat applied alone at 0.14 and 0.28 kg/ha, or tank mixed with alachlor [2-chloro-N-(2, 6-diethylphenyl)-N-(methoxymethyl)acetamide] at 4.40 kg/ha. Weeds were hand-removed so that only herbicidal treatments were variables. Paraquat phytotoxicity did not differ between cultivars. No cultivar evaluated was abnormally sensitive nor tolerant to any paraquat-containing treatment. Laboratory studies utilizing radio labelled paraquat revealed that foliar absorption and translocation of paraquat did not vary between peanut cultivars. Yield differences were attributed to differences in yield potential between cultivars.
Geocarposphere Temperature as It Relates to Florunner Peanut Production
Authors: Davidson J. I. , Blankenship P. D. , Henning R. J. , Guerke W. R. , Smith R. D. , Cole R. J. 
Published: April 2010

Abstract
Geocarposphere (GCS) temperature was correlated to yield, grade, jumbos (outturns), aflatoxin, and germination of Florunner peanuts grown in Southwest Georgia during CY 1981–1987. Maximum daily GCS temperatures usually provided better correlations with yield and quality factors than minimum and mean daily GCS temperatures. Maximum daily GCS temperatures were also more indicative of plant stress. Minimum GCS temperatures were important for rapid emergence, root growth, and maturation. Both maximum and minimum daily GCS temperatures were important for reducing impact by wet and dry weather pests. Maximum yield and quality will be produced when production practices are managed to maintain GCS temperature in the range of 20–35 C (68–95 F) at planting time, 20–31 C (68–87 F) prior to and during the early part of fruiting, 21–28 C (70–83 F) during primary pod addition and 21–29 C (70–85 F) during primary pod maturation period. However, maximum GCS temperatures below 27 C (80 F) should be avoided to minimize impact of wet weather pests. This and other information that relate scouting data and field history to yield and quality have proven useful in developing an Expert System and models for managing peanut production and marketing.
Pheromone Trapping as an Indicator of Southern Corn Rootworm Damage in Peanut1
Authors: Brandenburg R. L. , Barbour J. D. , Herbert D. A. 
Published: April 2010

Abstract
Populations of adult male southern corn rootworms (SCR) were monitored, and percent pod damage evaluated, for 107 peanut fields in the peanut growing regions of northeastern North Carolina and southeastern Virginia from 1986 through 1990. percent pod damage was not consistently related to numbers of adult male SCR as determined by pheromone trap catches, for any of the five years, or for all five years combined. However, fields with trap catches less than or equal to 45 beetles per trap per week (17% of those sampled) appeared to be at low risk for SCR damage. When SCR numbers averaged less than 45 beetles per trap per week, percent pod damage averaged less than 3% and variation was low (standard deviation=2.1%), indicating that this number may be used as a low-end cutoff for SCR treatment. The critical dependence of SCR on adequate soil moisture for survival of eggs and early instar larvae may be a major factor contributing to the lack of correlation between numbers of adult SCR and damage to peanut pods under field conditions.
Peanut Breeding for Drought Resistance1
Authors: Branch W. D. , Kvien C. K. 
Published: April 2010

Abstract
Because drought continues to be a major limiting environmental factor in peanut (Arachis hypogaea L.) production, a breeding strategy for developing drought resistance was initiated in the early 1980's at the University of Georgia, Coastal Plain Experiment Station. Crosses were made between advanced breeding lines and drought resistant germplasm. Rainout shelters were used between 60 and 120 days after planting to provide mid-season drought stress so that pedigree selection could be made within early-segregating generations. Eight pure-line selections from the GA T-2465 × Tifton-8 cross combination were first evaluation in irrigated yield trials. The Georgia selection, GA 901412 now GA T-2842, had the highest pod yield in two irrigated test during 1989 and 1990, and was found to have a 25% yield advantage over Florunner under severe drought stress during 1990. In 1991, this same drought resistant selection again had the top yield over 16 other Virginia/runner type cultivars in each dryland test at two Georgia locations. Thus, progress has been made in developing adapted drought resistant Georgia breeding lines, and such a breeding approach merits consideration for developing future drought resistant candivars.
Reproductive Efficiency in Reciprocal Crosses of Arachis duranensis and A. stenosperma with A. hypogaea cv. NC 61
Authors: Pattee Harold E. , Stalker H. Thomas 
Published: April 2010

Abstract
The wild species germplasm resources of Arachis are potentially valuable for improving disease and insect resistance in A. hypogaea L. Improving cultivars through interspecific hybridization is restricted because of reproductive barriers and/or genetic incompatibility with many Arachis spp. A description of reproductive efficiency in reciprocal crosses between wild and cultivated Arachis species is needed to clarify potentials for germplasm utilization. This study documents reproductive efficiency using the diploid species A. duranensis (K 7988) and A. stenosperma (HLK 410) in reciprocal crosses with A. hypogaea cv. NC 6. A significant parental effect was observed among crosses and NC 6 was more successful when used as the female parent. Differences in total reproductive efficiency were not observed between the two wild diploid species. However, when A. duranensis was used as a female parent embryos aborted at a high frequency. In contrast, the reduced efficiency observed with A. stenosperma was due to lower fertilization. As attempts are made to utilize the genetic resources of Arachis, different approaches will be needed to overcome reproductive barriers which restrict introgression of potentially desirable traits.
Paraquat Behavior as Influenced by 2, 4-DB in Peanut (Arachis hypogaea) and Selected Weeds1
Authors: Wehtje Glenn , Wilcut John W. , McGuire John A. 
Published: April 2010

Abstract
The interaction of 2,4-DB and paraquat on weed control and crop safety in peanuts was examined in greenhouse, field, and laboratory experiments. Tank mixtures of paraquat and 2,4-DB were no more injurious to peanuts than paraquat applied alone in greenhouse and field experiments. These tank mixtures were neither interactive nor synergistic with respect to weed control. Under field conditions, tank mixtures provided more comprehensive weed control and improved yield relative to either herbicide applied alone. Studies with 14C-labeled herbicides revealed that the absorption and translocation of paraquat and 2,4-DB was not influenced by the presence of other herbicide.
A Detached Shoot Technique To Evaluate the Reaction of Peanut Genotypes to Sclerotinia Minor1
Authors: Melouk H. A. , Akem C. N. , Bowen C. 
Published: April 2010

Abstract
The cut ends of 15-cm-long shoot tips from 15 peanut genotypes were immersed individually in 1 × 14 cm test tubes containing Hoagland's solution. Shoots were supported by foam plugs leaving about 12 cm extending above the foam plugs. All leaves were removed leaving about 1 cm of each petiole on the shoot. A 4-mm-mycelial plug of Sclerotinia minor, taken from the periphery of a 2-day old culture grown on potato dextrose agar containing 100 ug/ml streptomycin sulfate (SPDA), was placed between the stem and a petiole in the middle of the shoot. Tubes with shoots were then placed in a polyethylene enclosure on a greenhouse bench where the day and night temperature were 29 ± 2C and 25 ± 2C, respectively. Relative humidity (RH) was maintained at 95 to 100% by lining the bottom of the enclosure with wet burlap. Lesions appeared on shoot tips 3 days after inoculation, and their length was measured at various times. Genotypes with the least percent of symptomatic stems also had the lowest rates of lesion expansion. Two weeks after inoculation, tubes were drained, and shoots remained in the chamber at about 60–70% RH to allow sclerotial production. Sclerotia from each shoot were removed, counted, and their viability determined by germination on SPDA at 25 ± 2C in darkness. This method was effective in differentiating the reaction of peanut genotypes to infection by S. minor.
Productivity of Florunner Peanut Infected with Tomato Spotted Wilt Virus
Authors: Culbreath A. K. , Todd J. W. , Demski J. W. 
Published: April 2010

Abstract
Individual plants of peanut cultivar Florunner were evaluated over time for symptoms of tomato spotted wilt virus (TSWV) in field plots in 1988, 1989 and 1990. Time of symptom appearance was recorded for symptomatic plants. Seed yield was determined for individual symptomatic plants and apparently healthy check plants on adjacent rows. Across all times of appearance of symptoms, number of seed produced, mean weight per seed and total seed yield were lower for symptomatic plants than for healthy plants in all three years. In 1989 and 1990, linear regression indicated that both number of seed and seed yield per infected plant increased with time from planting until TSWV symptom expression. Mean seed weight also increased with time from planting until symptom expression in 1990, although this increase was small, but not in 1989. Among symptomatic plants, number of seed produced was more strongly correlated with seed yield than was average weight per individual seed.
Methods for Characterization of Kernel Density and Aflatoxin Levels of Individual Peanuts1
Authors: Gnanasekharan V. , Chinnan M. S. , Dorner J. W. 
Published: April 2010

Abstract
A helium pycnometer, specific gravity bottle and a displacement method were evaluated for the determination of individual peanut (Arachis hypogaea L.) kernel densities. Three coating materials were tested to minimize water absorption with the latter two methods. The displacement technique with a coefficient of variation (CV) of less than 0.1% was found to be most reproducible and had a total variability of 0.002 g/cm3. Polyurethane was adopted as the coating material of choice. A reverse phase High Performance Liquid Chromatography (HPLC) assay was adapted for quantification of the aflatoxins in individual peanuts. Picogram levels of aflatoxin were quantified with an average recovery of 82%. Characterization of peanut kernel density distributions and relationships between kernel density and aflatoxin level are envisioned with data generated using this method.
Resistance to the Peanut Root-Knot Nematode (Meloidogyne arenaria) in Arachis hypogaea1
Authors: Holbrook C. Corley , Noe James P. 
Published: April 2010

Abstract
The peanut root-knot nematode [Meloidogyne arenaria (Neal) Chitwood race 1] causes significant economic losses throughout the peanut (Arachis hypogaea L.) production area of the southern United States. Chemicals for control of this pest are becoming increasingly limited, and there are no known sources of resistance within the U. S. A. hypogaea collection. The objectives of this research were to screen 1,321 plant introductions for resistance or hypersusceptibility based on egg-mass ratings in greenhouse tests and to conduct more intensive greenhouse studies of selected genotypes to evaluate this method for identifying resistance to the peanut root-knot nematode. Twenty-seven genotypes with low and eight genotypes with high egg-mass ratings were selected and reevaluated in a more intensive greenhouse experiment. Seventeen of the low selections supported fewer (P≤0.05) egg masses, and seven supported less egg production per gram of fresh root weight than Florunner. Three selections for high egg-mass ratings supported more nematode eggs per plant than the cultivar Florunner and had a greater host efficiency. One of these genotypes supported more nematode eggs per gram of fresh root weight than Florunner. These results show that resistance to M. arenaria exists in the cultivated peanut species and can be selected by rating egg-mass production on greenhouse-grown plants.
Relationship of Rotterdam Peanut Prices to U. S. Peanut Production1
Authors: Carley D. H. , Fletcher S. M. , Zhang P. , Witt H. 
Published: April 2010

Abstract
In the 1980s exports of peanuts (Arachis hypogaea L.) from the United States ranged from 228,000 mt to 473,000 mt making up nearly 20% of the total U.S. production. The European Community was the largest importer of U. S. peanuts with Argentina and China the major U. S. competitors for peanut imports. Edible peanut prices quoted in Rotterdam are recognized as world reference prices in the peanut trade. From 1978 to 1990 monthly prices of U. S. 40/50 shelled peanuts in Rotterdam ranged from $600/mt to $2,100/mt. A change of $100/mt in the Rotterdam price results in an estimated change in the value of U. S. farmers' stock peanuts of $66/mt. Rotterdam prices are sensitive to monthly estimates of peanut production in the southeastern U. S. There is a critical southeast production threshold of about 1.0 mil mt, below which Rotterdam prices increase $125/mt for a decrease of 50,000 mt in production. Above the level of production, the price changed $51/mt for each 50,000 mt change in production. The Rotterdam price is an important barometer for domestic prices for additional peanuts produced by U. S. peanut farmers.
Fluazinam: A New Fungicide for Control of Sclerotinia Blight and Other Soilborne Pathogens of Peanut1
Authors: Smith F. D. , Phipps P. M. , Stipes R. J. 
Published: April 2010

Abstract
Fluazinam provided effective control of Sclerotinia blight (Sclerotinia minor Jagger) of peanut in six field trials during a 4-yr period. Applications of fluazinam (0.56 kg/ha) at the onset of Sclerotinia blight and 4 wk later provided an average of 69% suppression of disease incidence and increased yields by 1598 kg/ha compared to untreated plots. Performance of fluazinam was significantly better than iprodione, the material currently used for control of Sclerotinia blight. Two applications of iprodione at 1.12 kg/ha provided only 31% suppression of disease incidence and increased yield by 718 kg/ha. Fungicides were also evaluated in 1990 as tank-mixes with chlorothalonil (1.26 kg/ha) that were applied in foliar sprays according to the Virginia peanut leafspot advisory program. Treatments consisted of no fungicide, chlorothalonil alone, and tank-mixes of chlorothalonil plus either dicloran at 2.10 kg/ha, fluazinam at 0.56 kg/ha, or iprodione at 0.84 kg/ha. Sclerotinia blight at harvest in untreated plots and plots treated with chlorothalonil alone averaged 27.8 and 35.8 disease foci per plot, whereas yields averaged 3624 and 2251 kg/ha, respectively. Compared to plots treated with chlorothalonil alone, Sclerotinia blight was suppressed by 92, 25, and 25%, and yield was increased by 4020, 1925, and 1684 kg/ha in plots treated with chlorothalonil plus either fluazinam, iprodione, or dicloran, respectively. Applications of tank-mixes containing fluazinam plus chlorothalonil in 1991 provided additional evidence that this approach was a highly effective means of controlling both Sclerotinia blight and early leafspot, a previously unattainable goal. Fluazinam did not control early leafspot (Cercospora arachidicola S. Hori) in field trials; however, the fungicide was fungitoxic in vitro to Sclerotium rolfsii Sacc. and Rhizoctonia solani Kühn.
Rapid Screening Method for Resistance to Aflatoxin Production in Peanut1
Authors: Daren Xiao 
Published: April 2010

Abstract
A simple, economical, and rapid method to detect aflatoxin in peanut is described in this paper. The extract from 1 g of peanut is added to 1 mL of NH4H2PO4-HgCl2 solution containing 0.005 g agar in a tube. The concentration of aflatoxin can be visually estimated by the tube fluorescence which is directly correlated with the concentration of aflatoxin on a simple linear regression (r = 0.999, P &lt; 0.01). The lowest aflatoxin amount that could be detected was 0.02 μg/g by a spectroflurophotometer and was 0.04 μg/g by visual observation under UV light. There was no significant difference between the amounts of aflatoxin estimated by the tube fluorescence method and by TLC (P &gt; 0.10) in an experiment containing 10 samples. This method should be applicable for fast identification of peanut genotypes of single plants with resistance to aflatoxin production.
Physiology of Oil Seeds. X. Seed Quality of Peanut Genotypes as Affected by Ambient Storage Temperature1
Authors: Ketring Darold L. 
Published: April 2010

Abstract
Proper storage of peanut (Arachis hypogaea L.) pods following drying is a critical step in maintenance of seed quality for the next planting season. The objective of this study was to examine the effect of ambient storage temperature (similar to farmers stock peanuts stored in warehouses) on seed germination and seedling vigor of selected peanut genotypes. Peanuts were grown in the field for three successive seasons. Pods were harvested, dried, and shelled. Seed samples were taken for storage under ambient conditions, humidity effects were eliminated by storing the seeds in plastic freezer bags in sealed containers. Seasons were: (1) 1986, 19 months storage at ambient temperature, (2) 1987, 7 months storage at ambient temperature, and (3) 1988, seeds without storage. When comparisons were made among genotypes within seasons, exposure to Season 1 conditions resulted in the least germination and seedling growth, but a wide range of genotype diversity occurred. Germination of seeds from Seasons 2 and 3 ranged from 81 to 98%, and significant differences in seedling growth occurred among genotypes. When comparisons were made across Seasons, the data indicated a significant storage effect, which resulted in different seed quality for individual genotypes. Usually field emergence was significantly different among genotypes and was highly correlated with germination for all seasons. Generally, emergence was negatively correlated with slow seedling growth and positively correlated with rapid seedling growth. Thus, for seeds of lower vigor (Seasons 1 and 2), rapid seedling growth was particularly critical for early, uniform emergence (10 DAP) in the field. Genotypes were significantly different in extent of seed quality reduction and field emergence both within and across storage periods. Genotype diversity to ambient storage conditions suggests there is genetic potential to improve longevity of seed quality during storage and enhance stability of field emergence.
Single Leaf Carbon Exchange and Canopy Radiation Use Efficiency of Four Peanut Cultivars1
Authors: Bennett J. M. , Sinclair T. R. , Ma Li , Boote K. J. 
Published: April 2010

Abstract
Knowledge of the interception of solar radiation by crop canopies and the use of that radiation for carbon assimilation is essential for understanding crop growth and yield as a function of the environment. A field experiment was conducted in 1990 at Gainesville, FL to determine if differences in single leaf carbon exchange rate (CER), canopy radiation interception, radiation use efficiency (g dry matter produced per unit of solar radiation intercepted), and increase in seed harvest index with time exist among several commonly grown peanut (Arachis hypogaea L.) cultivars. Four cultivars (Early Bunch, Florunner, Marc I, and Southern Runner) were grown in field plots on a Kendrick fine sand (a loamy, siliceous, hyperthermic Arenic Paleudult) under fully irrigated, intensive management. Total crop and seed dry matter accumulation were determined, and canopy radiation interception measured at weekly intervals. CER of uppermost, fully expanded sunlit leaves were determined at midday at 2-wk intervals. Single leaf CER's were similar among cultivars (25 to 35 μmol CO2 m-2 s-1) and relatively stable throughout most of the season, before declining during late seed filling. Although interception of radiation differed somewhat among cultivars during early canopy development, total crop dry matter accumulation was linearly related to the cumulative amount of radiation intercepted by all four cultivars (r2=≥0.99). Radiation use efficiency was similar among all cultivars with a mean of 1.00 g dry matter accumulated per MJ of intercepted solar radiation. The increase in seed harvest index with time was linear (r2≤0.94) and the rates of increase were similar among the Early Bunch, Florunner, and Marc I cultivars (0.0058 d-1), but lower (0.0043 d-1) for the later maturing Southern Runner cultivar. Results from this study indicated that the primary differences among these four cultivars were in early-season development of the leaf canopy and resultant radiation interception and the rate of seed growth, rather than the capacity to assimilate carbon dioxide.