Sound Mature Kernels Research Articles

Impact of Sprinkler Irrigation Amount on Peanut Quality Parameters

Abstract Peanut quality parameters were analyzed across four irrigation levels during the 2002 through 2007 crop years. The peanut quality parameters consisted of total sound mature kernels and sound splits (farmer stock grade), shelling outturn by commercial edible size, accept and reject kernels by commercial edible size, seed germination, and aflatoxin. The four irrigation levels consisted of a full level (100%), two reduced levels (66% and 33%), and a non-irrigated control. The research was conducted at the USDA/ARS National Peanut Research Laboratory's Multi-crop Irrigation Research Farm in Shellman, Georgia. By year, significant differences in the irrigation treatments depended upon precipitation distribution for the specific quality parameters. For the average over the six years in the study, farmer stock grade was not significantly different in the 100, 66, and 33% treatments while all were significantly higher than the non-irrigated control. Total shelling outturn and total edible outturn were higher in the 100 and 66% compared to the 33% and non-irrigated treatments. Total reject outturn and total oil stock were not significantly different in the 100, 66, and 33% treatments, while all were significantly lower than the non-irrigated control. Percent seed germination did not differ across treatments. Aflatoxin in total reject outturn and total oil stock was significantly higher for the non-irrigated treatment compared to the irrigated treatments.

Single‐ and Twin‐Row Peanut Production within Narrow and Wide Strip Tillage Systems

Increased production costs and potential benefits of maintaining surface residue has renewed interest in conservation tillage systems for peanut (Arachis hypogaea L.) production. We determined surface residue cover from rye (Secale cereale L.) or oat (Avena sativa L.) cover crops after two strip tillage systems (narrow vs. wide) and planting operations with different row configurations (single vs. twin). We also compared plant populations, yields, and total sound mature kernels for three peanut cultivars (‘ANorden’, ‘AP‐3’, and ‘Georgia‐02C’) across each treatment combination. Seven site‐years were examined across similar soil types in Alabama and northern Florida during the 2004 to 2006 growing seasons. The highest surface residue counts were for the narrow tillage system planted in single rows. Final plant stands were influenced by an interaction between cultivar and row configuration, with ‘ANorden’ planted in single rows below recommended rates. Peanut yields were affected by strip tillage system and row configuration, but differences among cultivars were also observed. Twin‐row peanut yields were 5% greater than single‐row peanut yields in the narrow strip tillage system but were similar across strip tillage systems. Cultivars ‘AP‐3’ and ‘Georgia‐02C’ yielded 20% higher than ‘ANorden’. Total sound mature kernels were only affected by peanut cultivar, with the cultivar ‘Georgia‐02C’ producing the highest‐quality peanut, followed by ‘ANorden’ and ‘AP‐3’. These results indicate that growers interested in using twin rows for peanut production can also take advantage of a narrow strip tillage system that maximizes surface residue coverage and subsequent benefits.

Response of Texas Peanut to Chlorimuron Alone and in Various Combinations

Abstract Field studies were conducted in 2005 and 2006 in south Texas and the southern High Plains of Texas to determine peanut response to POST applications of chlorimuron at 9 g ha−1. Treatments included chlorimuron alone, imazethapyr applied 21 days after planting (DAP) followed by chlorimuron applied POST, and chlorimuron plus either 2,4-DB or chlorothalonil in combination applied POST. Postemergence herbicide applications were made 60, 74, and 88 DAP at the southern High Plains location or 67, 81, or 95 DAP at the south Texas location. No difference in peanut stunting was observed with any chlorimuron treatments at the south Texas location. At the High Plains location, chlorimuron alone, imazethapyr followed by chlorimuron, and chlorimuron in combination with 2,4-DB stunting was greater than chlorimuron in combination with chlorothalonil in one of two years. Imazethapyr followed by chlorimuron reduced peanut yield in one year in south Texas. No peanut grade (sound mature kernels plus sound splits) differences between chlorimuron treatments were noted at the south Texas location, but for the southern High Plains location, peanut grade was greater when peanut was treated with imazethapyr followed by chlorimuron compared to the other chlorimuron treatments.

Peanut (Arachis hypogaea L.) Response to the Ethylene Binding Inhibitor 1-Methylcyclopropene

Abstract Senescence and abscission of mature peanut pods is controlled by the ethylene cascade. Reducing senescence and abscission could involve inhibiting the ethylene cascade and allow greater harvest flexibility in peanut. Application of 1-methylcyclopropene (1-MCP), the ethylene binding inhibitor, may reduce senescence and abscission of mature peanut pods. Research was conducted from 2005 through 2008 in North Carolina to determine the effects of 1-MCP on pod yield and percentages of sound mature kernels (%SMK), sound splits (%SS), total sound mature kernels (%TSMK), other kernels (%OK), extra large kernels (%ELK), fancy pods (%FP), and pod retention. Treatments of 1-MCP were applied at 26 g ai/ha plus a crop oil concentrate at 7, 10, or 14 d prior to digging peanut at the projected optimum digging date. Peanut was dug at the projected optimum digging date or at 7 or 20 d after projected optimum digging date. The cultivars NC-V 11 (2005 and 2007), Phillips (2006 and 2007), and Perry (2008) were evaluated in separate experiments. Pod yield, %SMK, %TSMK, %SS, %OK, %ELK, and %FP were not affected by 1-MCP regardless of application timing when NC-V 11 and Phillips were evaluated. Only %SMK and %TSMK were affected by 1-MCP when applied to the cultivar Perry. Digging date affected pod yield and market grade characteristics. When digging of Phillips and Perry was delayed by 7 or 20 d past the optimum digging date, %SMK and %TSMK increased. Pod retention, determined by comparing the number and mass of pods/plant following digging, was affected by digging date and location but not 1-MCP treatment. These data suggest that 1-MCP will have little activity on peanut pod yield, market grade characteristics, or pod retention.

'AP-4', a Medium Maturity, Large Seeded Peanut Variety with Resistance to Tomato Spotted Wilt

SS-AGR-324, a 3-page illustrated fact sheet by Barry L. Tillman and Daniel W. Gorbet, describes this peanut variety was released by UF/IFAS in 2007 based on its competitive pod yield and excellent seed grade — total sound mature kernel percentage (TSMK), providing the results of tests in three locations over three years. Published by the UF Department of Agronomy, August 2009.

Yield and Plant Growth Response of Peanut to Midseason Forage Harvest

Harvesting of peanut (Arachis hypogaea L.) foliage during the growing season may increase farm revenue through the sale of peanut hay; however, it is unknown how the peanut plant will respond to forage removal with respect to plant characteristics, pod yield, quality, and revenue. This experiment was a randomized complete block design where peanut foliage was harvested or sprayed with a plant growth regulator prohexadione calcium (PHDC; Ca salt of 3, 5‐dioxo‐4‐propionylcyclohexanecarboxylic acid). There were nine treatments replicated five times. Peanut ‘Georgia Green’ was planted in twin rows during 2005 and 2006 on Tifton loamy sand. Peanut foliage was harvested at 20‐cm height at 60, 90, and 120 days after planting (DAP). The PHDC was applied at recommended rates and timing. Leaf density was higher for peanut plants treated with PHDC compared with plants cut for forage. Leaf‐to‐stem ratios were higher with plants harvested early (60 DAP) compared with those harvested later (120 DAP). Total forage mass was lowest at 60 DAP and increased with single or multiple harvests. Total forage removed with one single midseason harvest was not different from an associated multiple harvest. Peanut pod yield decreased about 12% for each harvest. Peanut grade (total sound mature kernels, TSMK) decreased as the number of harvests increased, conversely, other kernels (OK) increased as the number of harvests increased. Pod and forage revenue was highest for the nonharvest and single‐harvest treatments and decreased with the multiple harvests.

Factors Influencing Response of Virginia Market Type Peanut (Arachis hypogaea) to Paraquat under Weed-Free Conditions

Abstract Experiments were conducted during 2003 and 2004 to determine if peanut yield and market grade characteristics differed when paraquat was applied 24 to 28 days after emergence to peanut seeded in early, mid-, and late May and early June. Peanut pod yield and percentages of extra large kernels, total sound mature kernels, and farmer stock fancy pods were affected by planting date and paraquat independently. Paraquat did not affect yield compared with non-treated peanut regardless of planting date. In other experiments from 2003–2005, peanut was planted with or without aldicarb in the seed furrow and followed either paraquat applied 24 to 28 days after emergence or 2,4-DB applied in mid-August during 2003 and 2004. In 2005, experiments included a no-paraquat control rather than 2,4-DB. Pod yield was reduced at 3 of 9 sites due to damage from tobacco thrips, Franklinella fusca Hinds, feeding when aldicarb was not applied. Paraquat reduced yield in 4 experiments during 2005 but not in 5 experiments during 2003–2004. Aldicarb and paraquat affected peanut independently. Experiments were also conducted during 2005 and 2006 to compare interactions of paraquat formulations alone or with co-applied herbicides. Paraquat formulation (Gramoxone INTEON versus Gramoxone MAX or Firestorm) did not affect peanut response to paraquat, and interactions of paraquat formulation (Gramoxone MAX or Gramoxone INTEON) with bentazon, bentazon plus diclosulam, bentazon plus dimethenamid, bentazon plus imazethapyr, and bentazon plus S-metolachlor was similar to paraquat alone. Peanut injury and pod yield was the same when paraquat (Gramoxone INTEON) was applied alone or with carfentrazone and was similar to carfentrazone alone.

Peanut Yield and Grade Responses to Timing of Bahiagrass Termination and Tillage in a Sod-based Crop Rotation

Abstract Rotation of row crops with perennial grasses has been shown to improve soil quality characteristics, decrease pest incidence, and increase crop yield. Experiments were conducted in Florida during 2006 and 2007 at Marianna and Quincy to determine effects of termination date and subsequent tillage of established bahiagrass (Paspalum notatum L.) on peanut (Arachis hypogea L.) yield and market grade characteristics when rotating from bahiagrass to a row crop. Treatments included two bahiagrass termination dates (fall vs. spring) and six tillage methods [strip-till (in-row subsoiling), disk plus moldboard plow, disk plus chisel, disk plus paratill plus strip-till, disk, and strip-till with 45 kg N/ha]. Bahiagrass termination timing did not affect soil mechanical resistance, peanut yield or market grade characteristics, including percentages of sound mature kernels, split kernels, other kernels, and hulls. Although significant differences in soil mechanical resistance were detected among tillage treatments, peanut yield did not differ among the tillage methods except for the disk alone in 2007 at Quincy. Strip-till peanut yield did not respond to N application. When pooled over termination timing, peanut yields in strip-till, disk plus moldboard plow, disk plus chisel, disk plus paratill plus strip-till, disk, and strip-till plus 45 N were 4830, 5000, 4810, 4810, 4770, and 4620 kg/ha, respectively. These results indicate that when using perennial grasses in sod-based rotations, farmers have a wide window from fall to spring to terminate bahiagrass for optimum peanut production regardless of tillage system.

Registration of ‘AP‐4’ Peanut

‘AP‐4’ (Reg. No. CV‐106, PI 654070) peanut (Arachis hypogaea L. subsp. hypogaea var. hypogaea) cultivar was developed by the University of Florida, Florida Agricultural Experiment Station, North Florida Research and Education Center (NFREC) near Marianna, FL. Tested under the experimental designation UF03325, AP‐4 was approved for release in 2007. AP‐4 was developed from a cross made in 1996 between a University of Florida breeding line (88 × OL3‐HO6‐) and the F1 (‘Andru 93’ × F435‐HO). Lines were advanced using single seed descent in the F2 to F4 generations and pedigree selection in the F5 and F6 generations. Seed from three F7 plants were bulked to form the line later designated UF03325. AP‐4 has larger‐than‐average runner‐type seeds and pods. The average weight of 100 sound mature kernels of AP‐4 was 71 g compared with 57 g for ‘Georgia Green’ (P < 0.0001), a typical runner‐type cultivar. The prostrate growth habit of AP‐4 is typical of runner‐type peanut cultivars. Release of AP‐4 was based on its pod yield and seed grade (total sound mature kernels [TSMK]). In 19 tests in Florida over 3 yr, the TSMK of AP‐4 averaged 77% compared with 73% for ‘AP‐3’ (P < 0.0001). AP‐3 is most noted for its high level of resistance to spotted wilt caused by Tomato spotted wilt tospovirus, but low TSMK has restricted its acceptance among farmers. AP‐4 has competitive pod yield potential and good resistance to spotted wilt. The improved TSMK of AP‐4 should provide improved revenue compared to AP‐3.

Registration of ‘Florida‐07’ Peanut

‘Florida‐07’ (Reg. No. CV‐104, PI 652938) peanut (Arachis hypogaea L. subsp. hypogaea var. hypogaea) cultivar was developed by the University of Florida, Florida Agricultural Experiment Station, North Florida Research and Education Center near Marianna, FL. It was approved for release in 2006. Florida‐07 has larger‐than‐average runner market–type seeds and pods. The growth habit of Florida‐07 is prostrate, typical of runner‐type peanut cultivars. Under irrigation in Florida, it matures about 140 d after planting, which places it in the category of medium‐late relative maturity. Release of Florida‐07 was made on the basis of its excellent pod yield potential, competitive kernel grade (percentage total sound mature kernels), high‐oleic fatty acid oil chemistry, and resistance to spotted wilt (caused by Tomato spotted wilt tospovirus) and white mold (Sclerotium rolfsii Sacc.).

Using a Conveyor-Mounted Spout Sampler to Obtain Farmers Stock Grade Samples

Accurate determination of the value of load of peanuts is contingent upon obtaining a representative sample. Devices have been approved to extract a representative sample from a static load and from peanuts as they flow through an elevator downspout. A device that rotates a diverter through the flowing stream of peanuts to divert a small sample of peanuts for grading was mounted on the discharge of a belt conveyor. Tests were conducted in which the slot width was varied from 32 to 95 mm and sampling interval ranged from 20 to 120 s. The total mass of peanuts collected in a sample was recorded. After filling the trailer, a sample was retrieved using the conventional pneumatic sampler. Both grade samples were evaluated and quality parameters were compared. The percent foreign material and loose shelled kernels were lower in the spout samples (3.5% and 2.5%) compared to that observed in the pneumatic samples (4.2% and 3.3%). Foreign material also tended to decrease in the spout sample as the slot width increased. There were no significant differences in percent total sound mature kernels, other kernels, and hulls, thus making the peanut value the same regardless of sampling method. As expected, the amount of peanuts collected per swath increased as width of the slot increased, but was not affected by the sampling interval. Equations were developed to estimate the total sample size if the sampling interval, slot width, and total amount of peanuts passing through the sampler.

Interactions of Chlorpyrifos and Herbicides Applied to Peanut (Arachis hypogaea L.)

Abstract Experiments were conducted from 2004 through 2006 in North Carolina to determine peanut injury, pod scarring, pod yield, and percentages of extra large kernels (%ELK), fancy pods (%FP), and total sound mature kernels (%TSMK) following chlorpyrifos applied as a granular at pegging or as emulsifiable concentrate applied preplant incorporated (PPI) in mixture with pendimethalin. In one experiment, preemergence (PRE) herbicides consisted of S-metalochlor, S-metalochlor plus diclosulam, and S-metalochlor plus flumioxazin following chlorpyrifos. In a separate experiment, the postemergence (POST) herbicides acifluorfen, acifluorfen plus bentazon, imazapic, and paraquat plus bentazon were applied when peanut diameter was 10 to 15 cm. Chlorpyrifos did not interact with diclosulam or flumioxazin applied PRE or with the POST herbicides acifluorfen, acifluorfen plus bentazon, imazapic, or paraquat plus bentazon with respect to visual injury and pod yield. Applying chlorpyrifos at pegging was more effective than PPI applications in reducing pod scarification caused by southern corn rootworm (Diabrotica undecimpunctata Howardi) feeding. Although PRE and POST herbicides injured peanut in a manner consistent with standard application of these herbicides, pod yield, %ELK and %TSMK were not affected by early season injury. However, pod yield was lower in the experiment with POST herbicides when chlorpyrifos was applied PPI compared with granular application at pegging. No differences in pod yield, %ELK, %FP, and %TSMK were noted when comparing PPI and pegging applications of chlorpyrifos in the PRE herbicide experiment.

Virginia Market Type Peanut (Arachis hypogaea L.) Response to the Nitrophenolic Plant Growth Regulator Chaperone®

Experiments were conducted during 2004 and 2005 in Virginia and North Carolina to evaluate large-seeded, Virginia market type peanut response to a nitrophenolic plant growth regulator applied at 0.37 to 1.46 L/ha to peanut 45-60 DAP. Pod yield, percent extra large kernels (%ELK), percent total sound mature kernels (%TSMK), and crude protein levels of seed were not affected by the nitrophenolic plant growth regulator regardless of experiment (location and year). These experiments were conducted under a range of environmental and edaphic conditions with four cultivars. These data indicate that there is no benefit of applying the nitrophenolic plant growth regulator to Virginia market type peanut.

In-shell Bulk Density as an Estimator of Farmers Stock Grade Factors

The objective of this research was to determine if bulk density of in-shell peanuts, called pod bulk density can be used to accurately estimate farmer stock grade factors such as total sound mature kernels and other kernels. Physical properties including pod or in-shell bulk density, pod size, and kernel size distributions are measured as part of the cooperative Uniform Peanut Performance Tests (UPPT). Using physical property data from three years (2002–2004) of UPPT, analysis of variance were performed to determine the effect of bulk density, location, year, peanut type, and cultivar on percent total sound mature kernels (TSMK), other kernels (OK), and farmer stock value (FSV). Results indicated that all effects in the model were significant in predicting both TSMK and FSV and accounted for most of the variation (R 2 50.80). Linear regressions of the UPPT (2002–2004) data (with pod bulk density as a single factor) showed that TSMK and FSV increased as pod bulk density increased with poor R 2 values (R 2 50.2). A second set of data collected during the 2005 peanut harvest by Federal State Inspection Service (FSIS) had similar results. Location and peanut type were highly significant factors in the variation of TSMK, OK, and FSV. Overall correlation of grade factors with pod bulk density, location, and type was poor (R 2 ,0.5). Based on these data, pod bulk density cannot be used to accurately estimate TSMK and OK for marketing farmer stock peanuts. Observed pod bulk density averaged for UPPT (all years) and FSIS was 316 kg/ m 3 for runner, 427 kg/m 3 for spanish, 491 kg/m 3 for valencia, and 258 kg/m 3 for virginia peanuts.

Peanut (Arachis hypogaea) Response to Agricultural and Power Plant By-Product Calcium

Abstract Field studies were conducted at three locations in the south Texas peanut growing region to compare regular agricultural calcium with power plant byproduct calcium applied at planting or peanut pegging to runner peanut at rates of 560 to 1680 kg/ha. Both calcium sources decreased Rhizoctonia and Pythium pod disease development up to 62% when compared with the non-treated control and resulted in a yield increase over the non-treated control of up to 25%. When Rhizoctonia or Pythium was not a problem, no increase in peanut yield over the non-treated control was noted with any calcium application. Peanut grade (Total Sound Mature Kernels + Sound Splits) was increased at one location with the use of both calcium sources. Calcium, magnesium, and potassium content of foliage, hull, and kernel tissue was variable and was not related to calcium source.

Association of a Burrower Bug (Heteroptera: Cydnidae) with Aflatoxin Contamination of Peanut Kernels

Aflatoxin contamination of peanut kernels, Arachis hypogaea L., was associated with feeding by a burrower bug, Pangaeus bilineatus (Say). Kernel samples were divided into three grade categories: total sound mature kernels (TSMK), other kernels (OK), and damaged kernels (DK); and each of these grade categories was subdivided based on evidence of burrower bug feeding. Within TSMK, 100% of detectable aflatoxin contamination was associated with burrower bug kernel feeding, and kernels with feeding sites had a significantly higher concentration of aflatoxin than kernels without feeding sites (7.5 vs 0.0 ppb). Within the OK grade category, differences in aflatoxin contamination were not significant due to the inability to conclusively examine these kernels for feeding sites. Within the DK grade category, aflatoxin concentration was significantly higher in kernels with feeding sites than in kernels without observable feeding sites (286.5 vs 0.4 ppb), and 99.9% of contamination was associated with burrower bug feeding. Across all grade categories, aflatoxin levels were 65X higher in kernels with observable burrower bug feeding, and 98% of all aflatoxin contamination was associated with burrower bug feeding. The DK grade category had the highest concentration of aflatoxin and accounted for 45% of total contamination. Burrower bug-induced aflatoxin contamination of the TSMK grade category is particularly significant because this source would be most difficult to remove from the food supply. Contamination of the DK category is also economically significant because this grade component is specifically examined for Aspergillus at the buying point, and growers are severely penalized for detection.

Row Orientation and Seeding Rate on Yield, Grade, and Stem Rot Incidence of Peanut with Subsurface Drip Irrigation1

Abstract A 2-yr study was conducted on a Tifton loamy sand (fine-loamy, kaolinitic, thermic Plinthic Kandiudults) soil near Sasser, GA during the 2001 and 2002 growing seasons to determine the effects of three plant row orientations (single, twin, and multi-row) and two plant populations on the pod yield, market grade, and stem rot disease incidence of peanut when irrigated with subsurface drip irrigation (SDI). Seeds were planted at the recommended rate [20 seeds/m; 1.0R (recommended rate)] and half the recommended rate (10 seeds/m; 0.5R). Plots were irrigated daily to replace estimated daily evapotranspiration (ETa). Twin row orientation had the highest pod yield with 5407 kg/ha compared with the other row orientations, which averaged 4897 kg/ha. Market grade (total sound mature kernels, TSMK) for the twin and diamond row orientation was 1% point higher (74.7%) compared with the single row orientation. Pod yield was 8.5% greater for the 1.0R seeding rate compared with the 0.5R seeding rate. Stem rot incidence was highest in the single row orientation and lowest in the diamond row orientation. Within the three row orientations, kernel size distribution characteristics showed jumbo kernels had mixed percentages, with medium and ones showing no differences. The 1.0R plant population did have 4.4 % more jumbo kernels than the 0.5R plant population. This study indicates that twin row orientation and planted at the recommended rate (1.0R) had the best pod yield and market grade compared with single row orientation when irrigated with SDI.

IMPROVING PEANUT YIELD AND GRADE WITH SURFACE DRIP IRRIGATION IN UNDULATING FIELDS

A surface drip irrigation system was developed to irrigate peanut in two experimental fields: one with very littletopographic variation on Greenville fine sandy loam soil, and one with undulating terrain containing 2.4% slope on Facevillefine sandy loam soil. Pod yield, kernel size distribution, and total sound mature kernels (TSMK) were evaluated with twopeanut varieties, two planting patterns, and two drip tape lateral spacings. Test results were compared with the adjacentnon-irrigated area planted with the same varieties of peanut. Soil temperature and volumetric water content were measuredat different locations to monitor soil temperature and water movement from drip tapes. Maximum soil temperature in theirrigated area was substantially lower than in the non-irrigated area. For both 13 and 25 mm irrigations, about 16 h wererequired for water to move laterally 46 cm to reach the peak water content level. No significant difference (p < 0.05) wasobserved in yields between 0.9 m and 1.8 m drip tape lateral spacings. Peanut yields with drip irrigation were 1.4 times thoseof the non-irrigated yield. The irrigation water use efficiency from surface drip irrigation was 10 kg/ha-mm during the twogrowing seasons. Yields tended to slightly decrease as the land elevation decreased for both irrigated and non-irrigated zones.Compared to the non-irrigated areas, the drip-irrigated area produced a greater portion of larger kernels than smallerkernels. In the undulating area, the average TSMK was 73.7% and 64.9% for drip-irrigated and non-irrigated treatments,respectively. Average gross revenue was $2,093 per ha with drip irrigation and $1,253 per ha with no irrigation.

Burrower Bugs (Heteroptera: Cydnidae) in Peanut: Seasonal Species Abundance, Tillage Effects, Grade Reduction Effects, Insecticide Efficacy, and Management

Pitfall traps placed in South Carolina peanut, Arachis hypogaea (L.), fields collected three species of burrower bugs (Cydnidae): Cyrtomenus ciliatus (Palisot de Beauvois), Sehirus cinctus cinctus (Palisot de Beauvois), and Pangaeus bilineatus (Say). Cyrtomenus ciliatus was rarely collected. Sehirus cinctus produced a nymphal cohort in peanut during May and June, probably because of abundant henbit seeds, Lamium amplexicaule L., in strip-till production systems. No S. cinctus were present during peanut pod formation. Pangaeus bilineatus was the most abundant species collected and the only species associated with peanut kernel feeding injury. Overwintering P. bilineatus adults were present in a conservation tillage peanut field before planting and two to three subsequent generations were observed. Few nymphs were collected until the R6 (full seed) growth stage. Tillage and choice of cover crop affected P. bilineatus populations. Peanuts strip-tilled into corn or wheat residue had greater P. bilineatus populations and kernel-feeding than conventional tillage or strip-tillage into rye residue. Fall tillage before planting a wheat cover crop also reduced burrower bug feeding on peanut. At-pegging (early July) granular chlorpyrifos treatments were most consistent in suppressing kernel feeding. Kernels fed on by P. bilineatus were on average 10% lighter than unfed on kernels. Pangaeus bilineatus feeding reduced peanut grade by reducing individual kernel weight, and increasing the percentage damaged kernels. Each 10% increase in kernels fed on by P. bilineatus was associated with a 1.7% decrease in total sound mature kernels, and kernel feeding levels above 30% increase the risk of damaged kernel grade penalties.

A Note on the Accuracy and Variability of Grading and Marketing High Moisture Farmer Stock Peanuts

Abstract Previous research has shown that the farmer stock grade, lot weight, and market value could be accurately determined at kernel moisture contents greater than 10.5% without negative impact on either the producer or purchaser. In the 1998 and 1999 crop years, 686 farmer stock lots consisting of runner, Virginia, and Spanish types were graded and weighed at high moisture content (HMC), cured, and graded and weighed at low moisture content (LMC). The results indicated that LMC grade, lot weight, and lot value could be accurately predicted from HMC grade, lot weight, and lot value for individual farmer stock lots. However, the research did not address variability between HMC and LMC grade, weight, and values. In crop year 2001, a study was conducted in Georgia on runner-type peanuts to address variability in HMC and LMC grade, weight, and values. As farmer stock lots entered the buying point each lot was graded and weighed six times at HMC. The prediction equations estimated from the 1998 and 1999 studies were applied to the HMC values to obtain predicted grades, lot weights, and lot values. The lot was cured and graded and weighed six times at LMC and compared to the six predicted grades, lot weights, and lots values. Thirty-two farmer stock lots were included in the study. There were no significant differences in mean grade, lot weight, or lot value between the predicted and actual LMC values. Sound mature kernels and sound splits (SMKSS) differed by 0.07%. Mean lot weight differed by 7.7 kg (0.13%). Mean lot value differed by $20.11 (0.53%). Variability between predicted and actual SMKSS, lot weight, and lot value was not significantly different.