Influence of environmental factors on stem nodulation in Aeschynomene indica.

Abstract We reported that stem nodules were formed on the aerial parts of Aeschynomene indica plants grown in paddy fields at the frequency of 10% (Yoshida et al. 1985). Stem nodules were successfully formed by inoculation of Rhizobium isolates derived from both stem and root nodules of A. indica (Yoshida et al. 1985; Sasakawa et al. 1986). Maintenance of an adequate moisture level during the inoculation was an essential factor for successful stem nodulation and the supply of sucrose and/or yeast extract to the inoculant markedly depressed the stem nodulation (Sasakawa et al. 1986). Eaglesham and Szalay (1983) have reported that stem nodulation was inhibited by concomitant N supply to the host plants. However, little information is available on the role of other environmental factors such as temperature and light in stem nodulation.