抄録
In order to investigate the effects of temperature, inoculation and nitrogen application on a tropical legume Greenleaf desmodium a sand culture experiment was conducted in a phytotron at Kyusu University. It included 4 treatments of IN, IO, ON and OO, i.e., with (I) or without (O) inoculation and with (N) or without (O) nitrogen application under 4 temperature conditions of 15°, 20°, 25° and 30℃. Plants were sampled 45 days after treatments were imposed. Results obtained are as follows, 1) The highest dry matter yield was obtained at 25℃ in all the combinations of inoculation and N application. The effect of N application was found at every temperature imposed, however that of inoculation was found only at 25℃. 2) Total number of nodule was largest at 25℃ and was not reduced by N application. 3) N concentration of whole plant of ON, IO and IN plots was increased at the lower, the higher and over all temperatures, respectively. TNC concentration of ON plot at all temperature range was higher than that of IO plot which showed a higher value at low temperature, and that of IN plot were declined at a higher range but raised at a lower range of temperature. 4) The effective temperature range of N application was wider than that of inoculation which functioned only at at optimal range. This may be attributable to that the nodule became parasitic in respect to carbohydrate economy at the higher temperature and lost activity at the lower temperature. Accordingly it can be stated that the inoculation attended with N application is most effective at the optimal temperature to stimulate seedling growth of this legume and a little effective at extremely low or high temperatures due to compensatory effect of applied N for ineffectiveness of inoculation in those conditions.
