bluuebunny/crossref_metadata_2025_split huggingface dataset:
Integrated Method of Organizing, Computing, and Deploying Weather-Based Disease Advisories for Selected Peanut Disease
Authors: Bailey J. E. 
Published: April 2010

Abstract
Epidemiological information can be used with weather data to anticipate disease onset. These disease advisories can be applied to reduce the unnecessary use and improve the timing of fungicide sprays. Delivery of weather-based disease advisories to peanut growers in North Carolina was expedited by streamlining programming and information deployment procedures. This approach utilized a standard method of organization of weather data collection and analysis for all diseases, and daily reports were posted to the web. A standardized method of analysis is described which is flexible, and it allows information from epidemiological studies and practical experiences to be integrated to create a specific model for individual diseases. Included is a description of the research and extension activities over a 17-yr period during which weather-monitoring hardware and disease advisories were developed, tested, and utilized for advisories in peanuts at the farm level. Advantages and limitations to this approach with reference to its use in other crops are discussed.
Variation in Aggressiveness and Virulence Among Isolates of Cercospora arachidicola
Authors: Tuggle J. C. , Smith O. D. , Starr J. L. 
Published: April 2010

Abstract
Forty-three isolates of Cercospora arachidicola, incitant of early leaf spot of peanut, were collected from peanut fields in Florida, Georgia, North Carolina, and Texas. Variation in aggressiveness among these isolates using the susceptible peanut cultivar Spanco was examined in greenhouse tests. Variation (P ≤ 0.05) among the isolates was observed for the parameters of incubation period (IP), the reciprocal of the latent period (an estimate of sporulation rate), and number of lesions per leaflet (LN). Additionally, as a group, the isolates from Texas were more aggressive in terms of having a shorter latent period and greater number of lesions per leaflet than isolates from other states. When a subset of eight isolates, which differed in aggressiveness based on IP and LN, were tested on Spanco and three early leaf spotresistant breeding lines (TX957910–5, TX957910–27, TX957910–68), the breeding lines were resistant to all isolates and, except for lesion diameter, no host genotype-by-isolate interaction was detected (P &gt; 0.05). These observations suggest that success of efforts to identify resistance to early leaf spot can be affected by the aggressiveness of the pathogen isolate. Additionally, the resistance of the breeding lines tested is likely to be effective against a wide array of isolates of C. arachidicola.
Antigenic Diversity Among Peanut Stripe Potyvirus (Family Potyviridae) Isolates
Authors: Bhat A. I. , Pappu S. S. , Pappu H. R. , Todd J. W. 
Published: April 2010

Abstract
Several geographically and biologically distinct isolates of peanut stripe Potyvirus (PStV) were tested against available polyclonal and monoclonal antibodies. In direct antigen-coated, enzyme-linked immunosorbent assay (DAC-ELISA), the polyclonal antisera prepared against the purified virus reacted with all the isolates tested. However, a monoclonal antibody, 3AB5, also prepared against the purified virus showed dramatic difference in its reactivity to the same isolates. Tested against blotch isolates from Georgia, Virginia, and Florida, 3AB5 reacted with two of 10 isolates. The reaction was either strongly positive or negative. Antibody 3AB5 did not react with a necrotic strain of PStV from Taiwan. Results indicate the existence of antigenic diversity among PStV isolates.
Modeling Leaf Age-Related Susceptibility and Rust Eruption Dynamics in Peanut
Authors: Wang Z. Z. , Lin K. H. 
Published: April 2010

Abstract
To improve simulation of epidemics of peanut rust, information on the effects of leaf age and pustule eruption dynamics is needed. An analysis was made of the change of leaf susceptibility of rust with leaf aging using plants exposed to field inoculum. The youngest leaf was most susceptible to rust infection. As leaves aged, susceptibility decreased quickly. The relationship of infection frequency (Y, relative number of pustules) to leaf age (X, leaf position downward on the main stem) was described by a mathematical model Y = 2.17X(-0.83). The dynamics of pustule eruption also was studied using artificial inoculation. Analysis showed that after inoculation, pustule eruption over time was distributed in a logistic pattern. Rust eruption began at 130 and reach a peek at 250 rust degree days—that is, between 7 and 15 d after inoculation. Mathematical models of leaf age-related susceptibility and rust eruption dynamics will be incorporated into simulation model of rust epidemics.
Imazapic-Based Herbicide Systems for Peanut and Factors Affecting Activity on Florida Beggarweed
Authors: Wehtje G. , Padgett D. , Martin N. R. 
Published: April 2010

Abstract
Field studies were conducted over 3 yr to evaluate imazapic, applied either alone or combined with other commonly used herbicides for peanut weed control. Imazapic applied early postemergence alone at 71 g/ha provided excellent weed control, maximum yields, and optimum economic returns. Variations of this treatment—such as half rate of imazapic applied alone, tank mixed with other herbicides, or supplemented with other herbicides—frequently had equivalent weed control and yield. However, these variations did not improve economic return. Greenhouse studies evaluated Florida beggarweed control as influenced by weed age, imazapic rate, and application type. The three application types were foliage only, soil only, and soil plus foliage. Control was independent of application type when Florida beggarweed seedlings were less than 20 d old. The soil-only application did not adequately control older seedlings. Foliage-only and foliage plus soil application were equally effective. Averaged across all other factors, imazapic was less effective controlling seedlings older than 20 d. At this age, seedlings produced trifoliate rather than unifoliate leaves. Absorption of 14C-imazapic by unifoliate and trifoliate leaves was equivalent. However, translocation was greater in unifoliate leaves. Reduced translocation by trifoliate foliage contributes to imazapic tolerance of older Florida beggarweed seedlings.
Preharvest Aflatoxin Contamination in Drought-Tolerant and Drought-Intolerant Peanut Genotypes1
Authors: Holbrook C. C. , Kvien C. K. , Rucker K. S. , Wilson D. M. , Hook J. E. , Matheron M. E. 
Published: April 2010

Abstract
Peanuts become contaminated with aflatoxins when subjected to prolonged periods of heat and drought stress. The effect of drought tolerance on aflatoxin contamination is not known. The objectives of this research were to evaluate preharvest aflatoxin contamination in peanut genotypes known to have drought tolerance and to determine the correlation of drought tolerance characteristics with aflatoxin contamination. Twenty genotypes with different levels of drought tolerance were grown in Yuma, AZ (a desert environment) and under rain-protected shelters in Tifton, GA. Two drought-tolerant genotypes (PI 145681 and Tifton 8) and an intolerant genotype (PI 196754) were selected for further examination in a second experiment with two planting dates in 1997 at Tifton. Drought and heat stress conditions were imposed for the 40 d preceding harvest. The drought-intolerant genotype had greater preharvest aflatoxin contamination than Florunner (the check cultivar) in the tests conducted in 1997. Both drought-tolerant genotypes had less preharvest aflatoxin contamination than Florunner in these tests. Significant positive correlations were observed between aflatoxin contamination and leaf temperature and between aflatoxin contamination and visual stress ratings. Leaf temperature and visual stress ratings are less variable and less expensive to measure than aflatoxin contamination. Leaf temperature and visual stress ratings maybe useful in indirectly selecting for reduced aflatoxin contamination in breeding populations.
Alterations of Leaf Epicuticular Wax of Peanut (Arachis hypogaea) by Applications of Herbicides and Adjuvants1
Authors: Baysinger J. A. , Melouk H. A. , Murray D. S. 
Published: April 2010

Abstract
Leaf surface morphology of untreated peanut leaves and peanut leaves treated with herbicides and adjuvants were examined using scanning electron microscopy. Electron micrographs revealed that the adaxial surface of untreated peanut leaves was covered with crystalline wax platelets above an amorphous layer of wax. Electron micrographs revealed that peanut leaves treated with acifluorfen plus nonionic surfactant, bentazon and lactofen with crop oil concentrate, and 2,4-DB, altered the leaf surface morphology when compared to nontreated peanut leaves. Alterations in the leaf epicuticular wax structures appeared amorphous-like rather than normal plate-like structures. Nonionic surfactant and crop oil concentrate applied alone to peanut leaves altered the epicuticular wax structures similarly to that of herbicides plus adjuvants.
Impact of Plant Spacing and Population on Yield for Single-Row Nonirrigated Peanuts (Arachis hypogaea L.)
Authors: Sternitzke D. A. , Lamb M. C. , Davidson J. I. , Barron R. T. , Bennet C. T. 
Published: April 2010

Abstract
Poor peanut emergence often results in lower yield and loss of revenue. Farmers attempting to recapture lost income sometimes lose even more by replanting because replant costs may exceed the benefits of added yield. The purpose of this study was to develop an empirical equation to predict peanut yield based on total emergence 21 d after planting and an estimate of yield for a full stand of peanuts. Field experiments were conducted in Terrell Co., Georgia during 1997 and 1998 for nonirrigated peanut (cv. Georgia Green) grown in an Americus sand (thermic Rhodic Paleudults). To mimic poor emergence and concomitant random plant spacing, rows within plots were thinned at random locations to attain populations of 4.4, 3.3, 2.6, 2.1, and 1.6 plants/m-row. Control plots were not thinned and total emergence was approximately 12.7 plants/m-row. As total emergence and population decreased, yield also decreased whereas pod mass per plant increased. This increase was likely attributed to a reduction in competition from adjacent peanut plants for water, nutrients, and light. Higher population treatments had smaller pod mass/plant and greater overall yield than lower population treatments with higher pod mass/plant. Random plant-to-plant spacing associated with poor emergence was used to predict pod mass/plant as a function of average plant spacing. Results from this research established models defining the relationship of the rate of change of pod mass per plant with average plant spacing and provided a new method of predicting yield in the event of poor emergence.
Effects of Storage Environment on Farmers Stock Peanut Grade Factors in an Aerated Warehouse in West Texas
Authors: Blankenship P. D. , Grice G. M. , Butts C. L. , Lamb M. C. , Sanders T. H. , Horn B. W. , Dorner J. W. 
Published: April 2010

Abstract
Temperature and relative humidity (RH) in an aerated warehouse in west Texas were monitored during storage of 1994 and 1995 crop farmer stock (FS) peanuts. Temperature and RH were measured at various positions throughout a vertical cross section of the peanut mass in the overspace and outside the warehouse. Data were collected at 1-hr intervals throughout storage. Peanut mass temperatures averaged 9.6 C during storage for the 1994 crop and 10.3 C for the 1995 crop. Relative humidity for the 1994 crop storage averaged 68.3 and 57.9% for the 1995 crop storage. Farmer stock grades were collected at warehouse loading and unloading for 10- to 12-t lots of peanuts stored in the warehouse (Wpnuts) and for samples (Spnuts) positioned at temperature and RH sensor locations. Wpnuts, in approaching equilibrium moisture with ambient RH, lost 2% moisture content both storage years. Spnuts lost 1.4% moisture content during storage of both crops. Percentage sound mature kernels (SMK) from Wpnuts decreased by 3.3% during 1994 crop storage and 6.6% during 1995 crop storage. Percentage SMK from Spnuts decreased 2.2 and 6.2% for the two storage years. Percentage sound splits (SS) for the Wpnuts increased 2.2% during 1994 crop storage and 4.2% during the 1995 crop storage. Percentage SS for Spnuts increased 2.4 and 6.1%, respectively. Changes in other grade factors were not consistent comparing percentage values for Wpnuts and Spnuts. Data indicate that maintaining grade and quality during FS peanut storage in west Texas will require knowledge of moisture content of peanuts placed into the warehouse and environmental monitoring in order to determine storage length. For 3- to 5-mo storage, it is recommended that FS peanuts have a moisture content close to 10% when placed into storage for peanuts to be above 7% when unloaded from the warehouse.
Feasibility of Purchasing Screened Farmer Stock Peanuts: The Sheller's Perspective
Authors: Lamb M. C. , Blankenship P. D. 
Published: April 2010

Abstract
Mechanical screening to separate foreign material, loose shelled kernels (LSK), and smaller, lower value pods (thrus) from larger, higher value pods (overs) increased the value of peanut lots compared to unscreened lots. The average value of overs was $29.15 per Mg higher than unscreened peanuts. Marketing overs translates into higher purchase cost to shellers. The percentage of LSK in unscreened peanuts was a key factor in whether shellers would prefer to purchase screened lots because, as LSK of unscreened lots increases, the value per Mg of farmer stock (FS) peanuts decrease. The value of unscreened lots with 1% LSK was $12.33 per Mg less (not significant) than the resulting value of lots after screening, while the value of unscreened lots with 10% LSK was $57.57 per Mg less (P = 0.01) than the resulting value of lots after screening. LSK in screened lots were generally reduced to less than 1% limiting the availability of LSK for shellers to recover and use in edible channels. However, removal of high risk components (LSK and small kernels) should reduce aflatoxin levels in overs lots compared to unscreened lots. Significant increases in jumbo and medium outturn and decreases in No. 1 outturn were associated with shelling screened lots. Gross shelled stock value increased $32.37 per Mg for screened lots with no LSK recovery and $10.82 per Mg for unscreened lots with total LSK recovery. The differences in dollar returns from purchasing and shelling screened lots were compared to unscreened lots for different levels of LSK in unscreened lots and varying LSK recovery levels into edible channels.
Winter Fallow Management of Volunteer Peanut (Arachis hypogaea L.) and Cutleaf Eveningprimrose (Oenothera laciniata Hill)
Authors: Johnson W. C. , Baldwin J. A. , Mullinix B. G. 
Published: April 2010

Abstract
Volunteer peanut and cutleaf eveningprimrose are part of the epidemiology of spotted wilt disease of peanut and other susceptible crops in the Southeastern U.S. Coastal Plain. Studies were conducted on the timing and frequency of fallow harrowing, integrated with applications of glyphosate or tribenuron-methyl, for control of volunteer peanut and cutleaf eveningprimrose. Spring harrowing was generally more effective in controlling volunteer peanut than fall or winter harrowing. Conversely, cutleaf eveningprimrose was controlled by sequential harrowing in the fall, winter, and spring, with single harrowing less effective. In general, spring applications of glyphosate or tribenuron-methyl were equally effective in controlling volunteer peanut and cutleaf eveningprimrose in absence of tillage.
Comparison of Virginia and Runner Market-Type Peanut (Arachis hypogaea) Grown in the Virginia-Carolina Production Region
Authors: Jordan D. L. , Swann C. W. , Spears J. F. , Brandenburg R. L. , Bailey J. E. , Tucker M. R. 
Published: April 2010

Abstract
Research was conducted in North Carolina and Virginia from 1997 through 1999 to compare runner and virginia market-type peanuts as influenced by cultivar selection, fertility practices, and pest management strategies. The runner market-type cultivar Georgia Green yielded and provided gross market value equivalent to the virginia market-type cultivar NC-V11 under a wide range of edaphic and environmental conditions. Calcium (as gypsum) applied at initial pegging increased the percentage of extra large kernels, the percentage of total sound mature kernels, and market value (c/kg) of the virginia market-type cultivar Gregory. The runner market-type cultivars Georgia Green and GK-7 were less responsive to calcium. Response of both market types was dependant upon environmental conditions. Pest management strategy affected pod yield, gross value, and economic return of peanut similarly for both virginia and runner market types. Results from these studies suggest that runner market-type peanut can provide pod yield, gross value, and economic returns similar to commonly grown virginia market-type peanut when grown in the Virginia-Carolina region. However, the peanut industry in the Virginia-Carolina region is designed for virginia market-type peanut used for the in-shell market, and popularity of growing runner market-type peanut in this region will most likely depend upon market pressures rather than agronomic potential.
Expression of Nematode Resistance in Plant Introductions of Arachis hypogaea
Authors: Timper P. , Holbrook C. C. , Xue H. Q. 
Published: April 2010

Abstract
The peanut root-knot nematode (Meloidogyne arenaria, race 1) is a world-wide pest of peanut (Arachis hypogaea L.). Several moderately resistant genotypes have been identified in the cultivated peanut species. Our objective was to determine the expression of resistance for six of these genotypes. We examined four potential expressions of resistance—(a) fewer second-stage juveniles (J2) penetrate the roots, (b) fewer J2 establish functional feeding sites, (c) slower maturation, and (d) reduced fecundity (eggs per female). Seedlings of the susceptible cultivar Florunner and the resistant genotypes were inoculated with J2 of M. arenaria, and transplanted 3 d later to synchronize nematode development. Penetration was assessed at 3 and 10 d; development at 10 (or 12), 17, 22, and 27 d; and fecundity at 60 d after inoculation. The experiments were conducted in a greenhouse or growth chamber. The number of J2 within the roots was similar in resistant and susceptible peanut after 3 d; however, numbers were lower in two of the resistant genotypes than in Florunner after 10 d. A greater percentage of J2 failed to develop in all of the resistant genotypes (72 to 79%) than in Florunner (50%) after 17 d. Of the J2 that did begin to develop, the rate of maturation and fecundity was similar in resistant and susceptible genotypes. A lack of development indicates that the J2 failed to establish a feeding site. Therefore, the primary expression of resistance in the six peanut genotypes appears to be a reduction in the percentage of J2 that establish a functional feeding site. The decline in J2 after infection may be related to the failure to establish a feeding site.
Influence of Application Rate and Timing of Diclosulam on Weed Control in Peanut (Arachis hypogaea L.)
Authors: Grey T. L. , Bridges D. C. , Eastin E. F. 
Published: April 2010

Abstract
Field studies were conducted from 1996 to 1998 in Georgia to determine peanut (Arachis hypogaea L.) and weed response to ethalfluralin (0.8 kg ai/ha) plus diclosulam applied preplant incorporated (PPI) at 9, 18, 26, 35 and 52 g ai/ha. Other treatments included ethalfluralin PPI followed by paraquat plus bentazon (140 and 280 g ai/ha, respectively) early postemergence (EPOST) applied alone or following ethalfluralin plus diclosulam (18 and 26 g ai/ha) PPI, ethalfluralin PPI followed by imazapic (71 g ai/ha) postemergence (POST), and ethalfluralin PPI. Ethalfluralin was applied PPI in all herbicide programs. Diclosulam controlled Florida beggarweed [Desmodium tortuosum (Sweet) D.C.], sicklepod [Senna obtusifolia (L.) Irwin and Barneby], and yellow nutsedge (Cyperus esculentus L.) inconsistently, and POST application of paraquat plus bentazon was needed for acceptable control. However, diclosulam controlled common ragweed (Ambrosia artemisiifolia L.), tropic croton (Croton glandulosus Muell-Arg.), wild poinsettia (Euphorbia heterophylla L.), and prickly sida (Sida spinosa L.) without the need for POST herbicides. Higher yields were recorded with diclosulam PPI followed by a sequential application of paraquat plus bentazon than herbicide programs not containing diclosulam or diclosulam alone. Diclosulam PPI followed by sequential applications of paraquat plus bentazon provided greater control of sicklepod and prickly sida that resulted in greater yields. Yields from dicosulam PPI followed by paraquat plus bentazon EPOST were equivalent to yields with paraquat plus bentazon EPOST followed by imazapic POST or imazapic EPOST.
Genetic Relationship between Purple and Wine Testa Color in Peanut1
Authors: Branch W. D. 
Published: April 2010

Abstract
A better understanding of the genetic relationship among different testa colors is needed in peanut (Arachis hypogaea L.) breeding programs. Numerous genes are involved in this important U.S. market quality trait. However, the relationship among some of these genes is not yet known. The objective of this study was to determine the interaction among the three genes (P, w1, and w2) controlling purple and wine testa color. No maternal or cytoplasmic differences were found among three reciprocal purple x wine testcrosses. The F1, F2, and F3 segregation results suggest that purple testa color of PI 331334 differs from that of wine testa color parental lines (PI 264549, Wine-Frr 1 and Wine-Frr 2) by only two genes. These findings illustrate that the dominant purple testa color gene (P) is independent from at least one of the two recessive wine genes (w1 w1 or w2w2).
No-Pesticide Preliminary Yield Trials in Peanut1
Authors: Branch W. D. , Fletcher S. M. 
Published: April 2010

Abstract
Pest-resistant peanut (Arachis hypogaea L.) cultivars are critically important to reduce the increasing cost of production. Current pesticides used in the U.S. are effective but very expensive. The objective of this study was to evaluate several advanced Georgia breeding lines when grown without nematicides, fungicides, or insecticides. Preliminary yield trials without pesticides were conducted for 3 yr (1996-98) at the Univ. of Georgia, Coastal Plain Exp. Sta. under irrigation. However, preplant and occasionally post-applied herbicides were used for weed control. Thrips damage was noticeably uniform and severe early in the growing season each year, but plants seemingly recovered by midseason. Probably the most endemic diseases in the Southeast are both early and late leaf spots [Cercospora arachidicola Hori and Cercosporidium personatum (Berk. & Curt.) Deighton, respectively] and tomato spotted wilt virus (TSWV). Results from replicated field tests strongly suggest that it would be economically feasible to significantly reduce pesticide cost by growing multiple pest-resistant advanced Georgia breeding lines as compared to the five check cultivars Florunner, GK-7, Southern Runner, Florida MDR 98, and Georgia Browne. However, dollar values were variable and low with no pesticides because of the overall reduction in yield. An alternative approach for greater net returns possibly may be achieved by only reducing currently recommended input costs rather than eliminating pesticides with pest resistant cultivars.