Author
CANTONWINE, E - Valdosta State University | |
KENDRICK, C - Valdosta State University | |
AUERBACH, J - Valdosta State University | |
CULBREATH, A - University Of Georgia | |
Holbrook, Carl - Corley | |
BOUDREAU, M - Hebert Green Agroecology |
Submitted to: American Peanut Research and Education Society Abstracts
Publication Type: Abstract Only Publication Acceptance Date: 4/10/2009 Publication Date: 1/15/2010 Citation: Cantonwine, E.G., Kendrick, C., Auerbach, J., Culbreath, A.K., Holbrook Jr, C.C., Boudreau, M. 2009. Genetic and seed treatment effects on stand establishment in organically managed peanut fields. Proceedings American Peanut Research and Education Society 41:81. Interpretive Summary: not required Technical Abstract: Poor emergence and uneven stands are common for organic peanuts in the Southeast, even under ideal planting conditions. Experiments were conducted to evaluate the effects of naturally occurring chemical and biological seed treatments, peanut genotype, and shelling procedures (mechanical shelling vs. hand-shelling) on stand establishment, seedling vigor, and incidence of Rhizopus spp., the cause of Rhizopus seed rot, and Aspergillus niger, the cause of Aspergillus crown rot. Seed of the cultivar Georganic were treated with Kodiak, Actinovate, sulfur, CuSO4, or Kocide alone or in combination at 4oz/100 lb seed and placed on PDA agar plates. Incidence of Rhizopus was recorded after 3 days and incidence of A. niger after 5 days. The biological treatments, Kodiak and Actinovate, provided a numerical reduction to incidence of A. niger by 50% compared to the untreated control (P>0.05), but did not show activity against Rhizopus. The copper-based treatments reduced Rhizopus incidence by 50% compared to the control (P<0.05), but did not show activity against A. niger. Combinations of biological and copper-based treatments provided similar results to the copper-treatments alone. Sulfur showed no activity against either pathogen. In 2007 under field conditions, seed of thirteen peanut genotypes, mechanically shelled or hand-shelled, and treated with Kodiak seed treatment or untreated, were planted to monitor seedling emergence, seedling biomass, and incidence of Aspergillus crown rot. Kodiak did not significantly affect the variable observed. There was a 50% reduction of crown rot incidence in the hand-shelled plots compared to the mechanically shelled plots (P=0.06), and the hand-shelling significantly improved seedling emergence compared to mechanical shelling for five of the genotypes evaluated. Genotypes AP3, C34-24-69, and C34-24-124 had the best emergence rates (82-83%), while C724-19-25, C11-154-61, Georgia Green, and AP3 had the greatest biomass after 3 weeks. The cultivar Georganic was among the genotypes with the least amount of biomass. The field experiment will be repeated in 2009. |