Evaluation of Lupinus albus L. germplasm for the southeastern USA

While white lupin (Lupinus albus L.) has potential as a new minor winter crop, adapted germplasm have to be discovered and considerations for cold tolerance, pest resistance, and other traits determined. We evaluated 100 accessions in 1990-1991 and 616 in 1991-1992 at two locations in central Alabama, USA. Twenty-four seeds per accession were hand sown in an upland area on a Marvyn sandy loam (fine-loamy, kaolinitic, thermic, Typic Kahapludults) and in a river bottom area on a Wickham fine sandy loam (clayey, kaolinitic, thermic, Typic Rhododults). Backward stepwise and canonical discriminate analysis (CDA) was used to determine which agronomic traits and groups of accessions were most important for adaptation. Accessions were selected for further evaluation and breeding on the basis of survival through physiological maturity in 1990-1991 and on grain yields >= 27.6 g plot(-1) (2128 kg ha(-1) equivalent) in 1991-1992. The first two canonical discriminate variates (CAN) had Eigenvalues >= 1 and accounted for >= 51% of the total variance for both years. Vernalization type ratings (winter, semiwinter, spring) were most highly correlated (>= 0.87) with CAN 1 for both years, so CAN 1 was labeled vernalization type. The continuum for vernalization requirements was represented by CAN I in the 1990-1991 data. On the basis of correlations with CAN 2 for both years, earlier flowering of spring types was detrimental to survival. Selection of accessions with cold tolerance proved to be more important than extremely high vernalization requirements in severe winter types. Brown spot leafspot and root rot [caused by Pleiochaeta setosa (Kirchn.) Hughes] were the most prevalent diseases. East and West Mediterranean germplasm comprised > 55% of the selections for further testing; these lines were better adapted to the Southeast, while Southwest Asian and North African severe spring types with little or no vernalization requirement were better suited for use in short season areas of the northern USA.