Effect of Lime, Inoculant, and Molybdenum Pelleting of Seed on Growth and Nitrogen Content of Crownvetch1

Abstract

AbstractThere is a growing interest in the use of crownvetch (Coronilla varia L.) for hay or pasture. Crownvetch has been widely used on highway banks, but there have been problems with getting good stands. The present study was conducted to evaluate the influence of pelleting seed with lime, molybdenum, and inoculum on germination, growth, and N content of crownvetch.Gum arabic was used to secure materials to ‘Penngift’ crownvetch seed. A Culleoka silt loam soil with pH 5.0 and Grigg extractable Mo content of 0.56 kg/ha was used in greenhouse studies. Results showed that inoculant and Mo increased dry weight and N content of both tops and roots of crownvetch. Sodium molybdate at 70 g/ha was equally effective when pelleted to the seed or mixed uniformily with the soil. Neither pelleting nor uniform mixing of lime at the rate of 1.4 kg/ha influenced dry weights or N contents of roots or shoots in this soil, but uniform mixing of lime at the rate of 420 kg/ha significantly increased root weight. There was no significant treatment effect on germination but lime tended to reduce germination.Numbers of surviving rhizobia in laboratory tests varied with storage time and treatment. By three days after wetting with water and gum arabic many rhizobia had died. Greatest reductions in numbers occurred when sodium molybdate was present except when the inoculum was attached to the seed first and separated from the Mo by a layer of lime. Only small losses of rhizobia occurred from the third to the ninth day of storage.