Responses of Soybean (Glycine max L.) To Soil Solarization and Rhizobial Field Inoculation at Dang Ngaoundere, Cameroon

Field experiments were conducted to investigate the performance of two soybean (Glycine max L.) cultivars under soil solarization and rhizobial inoculation. Trials were carried out during the first cropping season of 2004 and 2005 at Dang Ngaoundere in the Guinea Savannah zone of Cameroon. In addition to one month soil solarization schedule performed during the first year, two and three months schedules were surveyed during the second year to identify the most efficient duration of solarization for plant growth improvement. The experimental design was multifactorial comprising three randomized factors: inoculation, cultivar and soil solarization. Results indicated that one month soil solarization was not enough to improve growth parameters of C1 and C5 soybean cultivars. Two months soil solarization increased plant biomass by 47 and 85%, flowering by 70 and 62% and seed yield by 75 and 85%, respectively for C1 and C5 cultivars compared to the control. Similarly, nodulation and seed yield were improved by rhizobial inoculation. The combined effect of two months soil solarization and rhizobial inoculation on growth parameters differed from one cultivar to another. Although three months soil solarization was the least effective treatment, it enhanced plant biomass by 14 and 32% and seed yield by 61 and 30%, respectively for C1 and C5 cultivars.