Studies are reported which follow the changes in starch, sugar, fresh and extraction residue weights of peanut fruit parts during maturation. Observations are also reported on the lipid content of the seed. Starch and sugar contents reached maximum levels first in the pericarp (hull) and then the seed coat (testa). Starch maxima occurred at early and middle maturity (stages 3 [10 mg] and 7 [10 mg]) and sugar maxima at a stage approaching middle maturity and at middle maturity (stage 6 [47 mg] and 8[9 mg]), respectively. In the seed, starch reached a maximum just beyond middle maturity (stage 9 [55 mg]) and then remained constant. Sugar content increased throughout maturation and lipid content became maximum at full maturity (stage 13 [415 mg]) then declined to 385 mg at over-maturity (stage 15). The role of regulating substrate supply to the developing seed seemed to shift from the pericarp to the seed coat with increasing maturity. Observed increases in fruit residue weight suggest that the pericarp is competing with the seed for metabolic resources during the late maturity stages.

‘Bailey’ (Reg. No. CV‐111, PI 659502) is a large‐seeded virginia‐type peanut (Arachis hypogaea L. subsp. hypogaea var. hypogaea) with partial resistance to five diseases that occur commonly in the Virginia‐Carolina production area: early leaf spot (caused by Cercospora arachidicola Hori), late leaf spot [caused by Cercosporidium personatum (Berk. & M.A. Curtis) Deighton], Cylindrocladium black rot [caused by Cylindrocladium parasiticum Crous, M.J. Wingf. & Alfenas], Sclerotinia blight (caused by Sclerotinia minor Jagger), and tomato spotted wilt (caused by Tomato spotted wilt tospovirus). It also has partial resistance to southern stem rot (caused by Sclerotium rolfsii Sacc.). Bailey was developed as part of a program of selection for multiple‐disease resistance funded by growers, seedsmen, shellers, and processors. Bailey was tested under the experimental designation N03081T and was released by the North Carolina Agricultural Research Service (NCARS) in 2008. Bailey was tested by the NCARS, the Virginia Agricultural Experimental Station, and five other state agricultural experiment stations and the USDA‐ARS units participating in the Uniform Peanut Performance Tests. Bailey has an alternate branching pattern, an intermediate runner growth habit, medium green foliage, and high contents of fancy pods and medium virginia‐type seeds. It has approximately 34% jumbo and 46% fancy pods, seeds with tan testas and an average weight of 823 mg seed−1, and an extra large kernel content of approximately 42%. Bailey is named in honor of the late Dr. Jack E. Bailey, formerly the peanut breeding project's collaborating plant pathologist.

No abstract

Improvement of flavor quality is a breeding objective that merits increased attention. To obtain further information on broad-sense heritability of selected sensory attributes, 30 virginia-type genotypes sources were grown in replicated experiments at two locations during 1988 for evaluation. Roasted peanut paste samples were evaluated for 14 sensory attributes. Fruity attribute was confirmed as having a significant suppressive effect on roasted peanut attribute. Session-to-session variation was significant and use of an incomplete block design provided for control of panel variation in the experimental error. Broad-sense heritability estimates for roasted peanut, sweet, and nutty sensory attributes were higher than previously reported, 0.31 vs. 0.24; 0.68 vs. 0.14; 0.37 vs. 0.05, respectively. Nine genotypes were found to have statistically significant higher roasted peanut intensity than the industry accepted standard Florigiant. Further calculations showed that experiments with two replications at each of four locations should have an 80% chance of detecting statistical significance for roasted peanut attribute differences of 0.5 units among genotypes when testing at the 5% level. A similar experiment with two replications at two locations should have a 40% chance of detecting statistical significance.

The high-oleic-acid trait improves the oxidative stability of peanuts (Arachis hypogaea L.) and their products. The explicit effect of the trait on sensory quality, particularly on off-flavors associated with oil rancidity, has not been well documented. To assess the effect of the trait on off-flavors, data from two independent databases were analyzed to compare sensory quality and composition in normal- versus high-oleic peanut genotypes. In data collected using a sensory panel in the Department of Food Science at North Carolina State University, there were small differences between near-isogenic lines for intensities of the roasted peanut, astringent, over-roast, and nutty attributes, with the high-oleic lines exhibiting slightly greater intensities of those attributes. There were no differences for off-flavors such as fruity, painty, stale, moldy, or petroleum. In data collected from the multistate Uniform Peanut Performance Test and evaluated by a panel in the USDA-ARS Market Quality and Handling Research Unit (MQHRU) at Raleigh, NC, there were differences in chemical composition associated with the high-oleic trait, including differences in oil content, tocopherols, and carbohydrates in addition to the expected differences in fatty acid contents. There were small decreases in the intensities of the sensory attributes cardboard and painty associated with the high-oleic trait in the MQHRU data when all high-oleic lines were compared with all normal-oleic lines. Comparison of the near-isogenic pair NC 7 and N00090ol showed differences in oil and glucose contents, but not in sensory attributes. The high-oleic trait does not appear to have a major impact on sensory quality on average, although there were individual instances in which the trait was associated with shifts in sensory attribute intensities that may be perceptible to consumers.

Roasted flavor is a critical factor in the acceptance of a peanut cultivar. A three-year study was made on the variation in roasted peanut flavor intensity of U.S. peanut cultivars and advanced breeding lines. An initial set of 83 entries was reduced to 71 by removing samples that showed evidence of extraneous environmental conditions, immaturity, and handhng or improper sample preparation effects. All entries for the cv. New Mexico Valenicia C, representing the valencia market type, were lost because of improper roasting or intense fruity flavor. Florigiant, Florunner, and Pronto were used as comparison standards for roasted peanut attribute values in evaluating the virginia, runner, and Spanish market types, respectively. The positive estimated difference between control and test germplasm sources was largest within the virginia type, with a least-square mean difference of + 1.4 for roasted peanut attribute intensity. Spanish types were next with a positive estimated difference of +1.3, and runner types were lowest with a positive estimated difference of +0.5. Broadsense heritability for the roasted peanut attribute among germplasm sources was determined to be 24%, suggesting a potential for improving the roasted peanut attribute level through proper breeding stratagems.

Peanut composition is influenced by several groups of factors: environmental, genetic, and their interaction. This study evaluated the relative contributions of these factors using data from the USDA-ARS quality testing program using samples from the multi-state Uniform Peanut Performance Tests (UPPT). Data were subjected to restricted maximum likelihood estimation of variance components reflecting the main effects of year, production region, location within region, genotype (cultivar or breeding line), and kernel grade (''seed size'') within genotype, and the interactions among these main effects. Genetic variation in oil content was low (9% of total variation); however, fatty acid composition of the oil was highly influenced by genotype (34-77%) with the exception of lignoceric acid (1%). Genetic influence on tocopherols was generally less than that of fatty acids. Environmental variation of tocopherols was greater than the variation attributable to genotype-by-environment interaction. The lowest genetic variation was observed in sugar content; however, environmental variation was high (68%). The magnitude of genetic influence on oil content and fatty acid concentrations suggests that these traits are amenable to improvement through breeding.

Carbohydrates are known to be important precursors in the development of roasted peanut quality. However, little is known about their genotypic variation. A better understanding of the role of carbohydrates in roasted peanut quality requires first an understanding of the genotypic variation in the soluble carbohydrate components. Ion exchange chromatography was used to isolate 20 different carbohydrate components in 52 genotypes grown in replicated trials at two locations. Inositol, glucose, fructose, sucrose, raffinose, and stachyose were quantitated, and 12 unknown peaks were evaluated on the basis of the peak height of the unknown relative to the cellobiose internal standard peak height. Peaks tentatively identified as verbascose and ajugose could not be properly integrated because of tailing. Of the 18 carbohydrates that were estimated, 9 exhibited significant variation between test environments, 5 among market types, 14 among genotypes within market types, and 11 exhibited some significant form of genotype x environment interaction. Genotypes accounted for 38-78% of the total variation for the known components, suggesting that broad-sense heritability for these components is high. The observed high genotypic variation in carbohydrate components is similar to the high genotypic variation observed for the sweetness attribute in roasted peanuts, which raises the question regarding possible interrelationships. The establishment of such interrelationships could be most beneficial to peanut breeding programs to ensure the maintenance of flavor quality in future peanut varieties.