Evaluation of Black Oat (Avena strigosa schreb.) Germplasm
Type of DegreeThesis
Agronomy and Soils
MetadataShow full item record
Black oat has become an important winter cover crop in subtropical and temperate regions. Originating in the northern parts of Spain and Portugal, black oat cultivation has spread to different parts of the globe. Even though different in ploidy level, diploid black oat has been used in many hexaploid common oat (A. sativa L.) breeding programs as a donor parent for some desirable characters such as rust resistance. Black oat is an emerging cover crop for the Southeastern US. The only commercially available black oat cultivar in US is ‘SoilSaver’ released by Auburn University and USDA-ARS-NSDL in 2002. Even though SoilSaver is superior for some traits (e.g. maturity and biomass yield), some traits need further improvement. Over 100 black oat accessions are available from the USDA-ARS Small Grains Germplasm Unit at Aberdeen, Idaho, but a detailed study of this collection is needed before they can be used in a breeding program. The objective of the study was to evaluate the entire USDA-NPGS black oat germplasm collection in the field for morphological traits and maturity and a subset for biomass and grain yield. We used 103 black oat accessions available from USDA and SoilSaver for the morphology and maturity study and 18 accessions selected based on their relative maturity compared to SoilSaver for plot biomass and grain yield trials. Among the 14 response variables measured, 12 were used for the “Canonical Discriminant Analysis” (CDA) in morphology and maturity study. In CDA the first four canonical variates were responsible for 84 % of the total variation and when plotted the first two axes, the accession CIav 9015 was separated farthest from the rest of the accessions. This accession is extremely early maturing, has short culms but long and broad leaves. So we suspect that it may not belong to Avena strigosa Schreb., but to some other Avena species. Further karyotypic studies may be needed to ascertain our findings in this regard. For the yield trials we compared the biomass and grain yield and test weight of the selected accessions to SoilSaver at a standard seeding rate. None of the tested accessions performed better than SoilSaver at standard seeding rate consistently in all locations. The allelopathy study identified seven accessions having significantly higher radish radicle suppressive ability than SoilSaver.