The number of Bradyrhizobium SP. (Lupinus) applied to seed and its effect on rhizosphere colonization, nodulation and yield of lupin

Trehalose and Abiotic Stress in Biological Systems

“…A way to encourage the formation of the legumerhizobia symbiosis could be the application of rhizobia to legume seeds prior to planting in the field. However, the percent of survival of rhizobia applied in this manner is very low, less than 5%, because of rapid desiccation (Roughley et al, 1993). By supplying external trehalose (3 mmol l -1 ) to Bradyrhizobium japonicum strain USDA 110, the concentration of trehalose in the cells increased threefold and bacteria survival in response to desiccation increased by two to fourfold (Streeter, 2003).…”

The Physiological Mechanisms of Desiccation Tolerance in Rhizobia

“…Peat inoculants available in Australia are generally of good quality and deliver high numbers of rhizobia; 10 9 to 10 10 cells g -1 of peat at manufacture . However, the number of cells being delivered per seed is limited by the surface area of the seed and the limited survival of rhizobia on seed 5 requires sowing to take place within a few hours of application (Roughley et al, 1993). A negative aspect of peat is variable quality as not all sources are suitable for use as inoculant carriers (Roughley and Vincent, 1967).…”

“…Colonization of the legume rhizosphere, nodulation, nitrogen fixation and yield are affected by inoculum potential (Roughley et al, 1993). However, the delivery of high numbers of viable rhizobia varies with legume inoculant formulation, method of application and soil conditions (Deaker et al, 2004).…”

“…However, the delivery of high numbers of viable rhizobia varies with legume inoculant formulation, method of application and soil conditions (Deaker et al, 2004). Roughley et al (1993) reported that 95% of Bradyrhizobium sp. died 7 between time of inoculation and sowing and 83% of the survivors died within 22.5 hours of being applied to the soil.…”

“…However, it has been found that the inoculum potential of liquid inoculants still cannot match that of moist peat inoculants. Inoculum potential may be defined as the number of rhizobia applied during inoculation and is calculated by multiplying the number of rhizobia per unit weight of inoculant by the application rate (Roughley et al, 1993). Singleton et al (2002) reported that 48 hours after inoculum application, the number of viable cells per soybean seed ranged from log 10 2.4 to log 10 5.0 for different formulations of liquid inoculant.…”