Response of Early, Medium, and Late Maturing Peanut Breeding Lines to Field Epidemics of Tomato Spotted Wilt

1999 ◽  
Vol 26 (2) ◽  
pp. 100-106 ◽  
Author(s):  
A. K. Culbreath ◽  
J. W. Todd ◽  
D. W. Gorbet ◽  
S. L. Brown ◽  
J. A. Baldwin ◽  
...  

Abstract Epidemics of tomato spotted wilt, caused by tomato spotted wilt Tospovirus (TSWV), were monitored in field plots of runner-type peanut (Arachis hypogaea L.) cultivars Georgia Green and Georgia Runner and numerous breeding lines from four different breeding programs as part of efforts toward characterizing breeding lines with potential for release as cultivars. Breeding lines were divided into early, medium and late maturity groups. The tests were conducted near Attapulgus, GA and Marianna, FL in 1997 and in Tifton, GA and Marianna, FL in 1998. Epidemics in some early and medium maturing breeding lines, including some genotypes with high oleic acid oil chemistry, were comparable to those in Georgia Green, the cultivar most frequently used in the southeastern U.S. for suppression of spotted wilt epidemics. No early maturing breeding lines had lower spotted wilt final intensity ratings or higher yields than Georgia Green. However, spotted wilt intensity ratings in some late maturing lines and a smaller number of medium maturing lines were significantly lower than those of Georgia Green. Several of those lines also produced greater pod yields than Georgia Green. Results from these experiments indicated that there is potential for improving management of spotted wilt though development of cultivars that suppress spotted wilt epidemics more than currently available cultivars. There was no indication that differences in spotted wilt ratings corresponded to differences in numbers of thrips adults or larvae.

2008 ◽  
Vol 35 (2) ◽  
pp. 81-85 ◽  
Author(s):  
S. P. Tallury ◽  
H. E. Pattee ◽  
T. G. Isleib ◽  
H. T. Stalker

Abstract Several diploid wild species of the genus Arachis L. have been used as sources of resistance to common diseases of cultivated peanut (Arachis hypogaea L.). Because flavor is among the most important quality attributes for commercial acceptance of roasted peanuts, sensory attributes of interspecific hybrid derived breeding lines were evaluated to determine if transfer of disease resistance from wild species is associated with concomitant changes in flavor. Sixteen interspecific hybrid derivatives with five diploid species in their ancestries and the commercial flavor standard, NC 7 were evaluated for sensory quality. Significant variation among entries was found for the roasted peanut, sweet, and bitter sensory attributes, but not for the overall contrast between NC 7 and the wild species-derived breeding lines. The variation was either between two groups of wild species-derived breeding lines or within one or both groups. Introduction of disease and pest resistance traits from Arachis species did not result in degradation or improvement of the flavor profile. This suggests that flavor of wild species-derived germplasm will not prevent its use either as parents in peanut breeding programs or as cultivars.


2008 ◽  
Vol 35 (2) ◽  
pp. 92-100 ◽  
Author(s):  
S. D. Riniker ◽  
R. L. Brandenburg ◽  
G. G. Kennedy ◽  
T. G. Isleib ◽  
D. L. Jordan

Abstract Tomato spotted wilt virus (TSWV), a thrips-vectored tospovirus, is an important pathogen of peanut (Arachis hypogaea L.). Development of tolerant cultivars has proven to be one of the most promising methods to manage the disease. Twenty-four genotypes of virginia market-type peanut were monitored in field tests for thrips damage, and TSWV incidence and severity during 2004 and 2005 in North Carolina. The cultivar Gregory had a higher density of adult thrips in foliage than any other genotype, while breeding lines N01057 and N03054E had the lowest density. No significant correlation was detected between thrips density or injury and TSWV incidence. Line N03036EJ had the greatest TSWV incidence, but did not differ from cultivars Gregory or Perry in incidence. Line N00033 had the least TSWV incidence and differed from the cultivars Gregory and Perry. The occurrence of late-season chlorosis or peanut yellowing death (PYD) was highly correlated with TSWV infection (P < 0.0001). Breeding line N02051ol had the greatest incidence of PYD, but did not differ statistically from Gregory or Perry. Lines N03023EF and N01083 had the least PYD incidence. Plants infected with TSWV not expressing foliar symptoms were found in far greater abundance than plants that were infected and symptomatic. Line N03036EJ had the greatest proportion of infected but asymptomatic plants; line N03054E had the least. Susceptible lines are more likely to become infected, rather than just more likely to show spotted wilt symptoms.


2002 ◽  
Vol 29 (2) ◽  
pp. 79-84 ◽  
Author(s):  
J. H. Lyerly ◽  
H. T. Stalker ◽  
J. W. Moyer ◽  
K. Hoffman

Abstract Tomato spotted wilt virus (TSWV) is an important plant pathogen with a wide host range, including the domesticated peanut (Arachis hypogaea L.). After initial outbreaks on peanut during the 1980s, the virus has spread to all peanut-producing states in the U.S. TSWV is transmitted by several species of thrips which are difficult to control with insecticides; therefore, control of TSWV most likely will come from selecting resistant genotypes in breeding programs. Although moderate levels of resistance have been discovered in A. hypogaea, complete virus resistance has not been found. Several Arachis species have desirable genes for plant resistances and tolerate many disease and insect pests better than the cultivated species. The objectives of this study were to (a) evaluate TSWV disease incidence and severity in accessions of Arachis species, and (b) compare levels of TSWV resistance in diploid species to selected A. hypogaea genotypes. In this study, 46 diploid Arachis spp. accessions were evaluated in the greenhouse by artificial inoculation tests for resistance to TSWV. Nine Arachis accessions were observed with no disease symptoms when TSWV isolate 10 was used as opposed to A. hypogaea lines that ranged from moderately to highly susceptible. Additional testing with more virulent isolates identified A. diogoi accession GKP 10602 and A. correntina accession GKP 9530 as highly resistant to the virus. These two accessions are being used as parents in crossing programs to incorporate TSWV resistance genes into A. hypogaea.


Plant Disease ◽  
2005 ◽  
Vol 89 (8) ◽  
pp. 910-910 ◽  
Author(s):  
J. E. Woodward ◽  
T. B. Brenneman ◽  
R. C. Kemerait ◽  
A. K. Culbreath ◽  
J. R. Clark

Because of the importance of spotted wilt caused by Tomato spotted wilt virus (TSWV), most peanut (Arachis hypogaea L.) breeding programs in the southeastern United States are focusing on developing resistance to TSWV. Many of the cultivars with improved resistance to TSWV are late maturing, requiring 150 days to reach optimum maturity. This factor could greatly impact disease problems at harvest. During November of 2004, an unknown disease was observed on peanut cvs. Georgia 02-C and Hull in a commercial field in Appling County. Symptoms included wilting stems with water-soaked lesions and a dense, gray mold growing on infected tissues. Final disease incidence was less than 5%. For isolation, diseased tissue was surface sterilized by soaking in 0.5% sodium hypochlorite for 1 min, air dried, plated on potato dextrose agar (PDA), and incubated at 20°C. Botrytis cinerea Pers.:Fr., causal agent of Botrytis blight, was isolated from the margins of infected tissue. Mycelia were initially white but became gray after 72 h at which time tall, branched, septate conidiophores formed. Mature, unicellular, ellipsoid, hyaline conidia (8.9 × 10.4 μm) formed in botryose heads (1). Hard, black, irregular-shaped sclerotia formed after 2 weeks. Stems of greenhouse-grown peanut plants (cv. Georgia Green) were inoculated with PDA plugs colonized with either B. cinerea or B. allii Munn. Inoculations were made 3 cm below the last fully expanded leaf on wounded and nonwounded tissue. Noncolonized PDA plugs served as controls (n = 9). Plants were arranged in a dew chamber at 20°C in a randomized complete block design. Lesions and spore masses identical to those observed in the field appeared 3 to 5 days after being inoculated with B. cinerea. The B. allii inoculations caused only superficial lesions. After 5 days, mean lesion lengths for B. cinerea were 59 and 37 mm for wounded and nonwounded inoculations, respectively. B. cinerea was recovered from 100% of the symptomatic tissues. Botrytis blight is considered a late-season disease that occurs in cool, wet weather (3). Symptoms similar to those of Botrytis blight were observed on mature and over-mature peanut in Georgia and have been cited as “unpublished observations” (2); however, to our knowledge, this is the first report of the disease in Georgia. Although Botrytis blight is not considered a major peanut disease, it may become more prevalent at harvest as producers utilize late-maturing cultivars to manage spotted wilt. References: (1) H. L. Barnett and B. B. Hunter. Illustrated Guide of Imperfect Fungi. 4th ed. The American Phytopathological Society, St. Paul, MN, 1998. (2) K. H. Garren and C. Wilson. Peanut Diseases. Pages 262–333 in: The Peanut, the Unpredictable Legume. The National Fertilizer Assoc. Washington D.C. 1951. (3) D. M. Porter. Botrytis blight. Pages 10–11 in: Compendium of Peanut Diseases. 2nd ed. N. Kokalis-Burelle et al., eds. The American Phytopathological Society, St. Paul, MN. 1997.


2009 ◽  
Vol 25 (3) ◽  
pp. 541-548 ◽  
Author(s):  
Noelle A. Barkley ◽  
Kelly D. Chenault Chamberlin ◽  
Ming Li Wang ◽  
Roy N. Pittman

2008 ◽  
Vol 35 (1) ◽  
pp. 61-66 ◽  
Author(s):  
W. D. Branch ◽  
A. K. Culbreath

Abstract Interest in organic peanut (Arachis hypogaea L.) production is increasing in the United States. Disease and insect resistant cultivars will be needed to meet the challenge of producing peanuts without conventional pesticides. No-fungicide and no-insecticide field trials were conducted under irrigation four consecutive years (2003–06) at the University of Georgia, Coastal Plain Experiment Station to evaluate peanut genotypes for pest resistance. The most important foliar peanut diseases in the southeast are tomato spotted wilt (TSW) caused by Tomato spotted wilt virus and both early and late leafspots caused by Cercospora arachidicola Hori and Cercosporidium personatum (Berk. & Curt.) Deighton, respectively. Two of the most important insect pests on peanut are tobacco thrips (Frankliniella fusca Hinds) and potato leafhopper (Empoasca fabae Harris). Results from these no-fungicide and no-insecticide field trials showed significant differences (P ≤ 0.05) in pest resistance among advanced Georgia breeding lines and cultivars. Two Georgia cultivars ‘Georgia-01R’ and ‘Georgia-05E’ consistently produced the highest yields and had high levels of resistance to TSW, leafhoppers, and leafspots each year. Georgia-01R is a multiple-pest-resistant, mid-oleic, runner-type cultivar; whereas, Georgia-05E is a multiple-pest-resistant, high-oleic, virginia-type cultivar. Both cultivars should be considered as good candidates for potential use in organic peanut production.


Helia ◽  
2015 ◽  
Vol 38 (62) ◽  
pp. 121-140
Author(s):  
J. González ◽  
N. Mancuso ◽  
D. Alvarez ◽  
D. Cordes ◽  
A. Vázquez

AbstractThe sunflower breeding carried out in Argentina constitutes a valuable contribution to the spreading of the crop both locally and internationally. Exchange among breeders at international level makes it possible to achieve objectives that would be restricted if only local germplasm were available (lack of variability). The National Institute of Agricultural Technology (INTA) has had a sunflower genetic breeding program at Pergamino Experimental Station (EEA) since 1939 and another program at Manfredi Experimental Station (EEA) since 1950 with the overall goal of contributing to increase the rate of genetic progress of the crop. At first the program development open pollination varieties using the populations which were introduced both by immigrants adapted to local conditions and by intercrossing them. With the development of cytoplasmic androsterility in the 1970s, the programs focused on producing inbred lines to develop hybrids. The varieties and lines were made available to other breeders in a scheme of exchange that allowed INTA, other national breeders and breeders from other countries to obtain new materials. In this way it became clear the great wealth of INTA germplasm for resistance to major crop diseases such as Verticillium wilt, rust and downy mildew. Other important traits improved were the increase of seed weight and tolerance to bird damage by adding striated seeds and decumbent heads. Also by its origin INTA germplasm enabled the increase of oil content, improvements in the quality and specialties (high oleic acid, confectionery) and tolerance to herbicides (imidazolinone), while maintaining the performance and health of the materials. This paper describes the origins and characteristics of INTA lines and also their use in other breeding programs for the creation of new cultivars.


Sign in / Sign up

Export Citation Format

Share Document