Genotype and planting depth effects on seedling vigor in sericea lespedeza.

Abstract

Sericea lespedeza [Lespedeza cuneata (Dumont de Courset) G. Don.] is a small-seeded forage legume that can improve forage quality and nitrogen content of interseeded pasturelands. Poor seedling vigor has caused interseeding failure. This study was conducted to determine the effects of genotype, planting depth, and their interaction on seeding vigor of services lespedeza in the field, and to determine if seedling traits measured in a growth chamber can be used to predict seedling growth in the field. Substantial variability was found among 54 sericea lespedeza genotypes for traits that can be used in a breeding program to improve seedling vigor. All seedling traits were correlated with each other, indicating a high proportionality existed among plant parts. Thus, any of the seedling traits measured could be used to represent seedling vigor. Genotypes 73-162-16, AU L2, AU L13, and 'Serala 76' outperformed other genotypes for most seedling traits under field and growth chamber conditions. Planting to a depth of 3 cm did not reduce seedling vigor, and therefore, may be recommended when there is insufficient moisture in the upper layer of sandy loam soils at planting. Although measurements taken in the growth chamber did not reliably predict field performance, information gathered in the growth chamber provides a good means of increasing the frequency of superior plants to be tested in the field.