Studies on seed pelleting as an aid to legume seed inoculation. I. Coating materials, adhesives, and methods of inoculation

Abstract

The influence of seed-pelleting techniques on the inoculation and nodulation of subterranean clover (Trifolium subterraneum L.) was studied in the laboratory and in the field on podzolic soil where clover nodulation following conventional seed inoculation practices was often unsatisfactory. Seed pellets were prepared with the use of 10 different coating materials, three adhesives, and two methods of inoculation. These were sown immediately after preparation or stored for short periods before sowing, and were examined in terms of inoculant survival, nodulation, and plant growth. It was shown that subterranean clover seed pelleted with a lime, blood plus dolomite, or lime plus blood plus dolomite coating attached to the seed with a 45% solution of gum arabic and inoculated by incorporating a commercial peat inoculant within the pellet can be stored for up to 4 weeks before sowing and the viability of the inoculant retained. This is reflected in improved nodulation and in growth of the seedling subsequently produced. Ecological considerations in respect of the establishment of the inoculum in the soil are discussed.