Abstract

CALVO VELEZ, Pamela; REYMUNDO MENESES, Luis  and  ZUNIGA DAVILA, Doris. A study of potato (Solanum tuberosum) crop rhizosphere microbial population in highland zones. Ecol. apl. [online]. 2008, vol.7, n.1-2, pp.141-148. ISSN 1726-2216.

A study was conducted to investigate the microbial populations of the most representative genera in the potato rhizosphere in Highland regions. Total bacteria population in the two sampling regions was always higher than the fungi population. The more alkaline soil pH in Puno region can explain this fact. We observed that Actinomycetes and Azotobacter spp. populations were influenced by pH and type of inorganic fertilization. Also the populations of Bacillus spp. were higher in the region with neutral pH; nevertheless its presence in acid pH zones confirms its adaptation to these conditions. A potato variety effect was also observed on the microbial rhizospheric population which confirms the influence of plant exudates on the rhizosphere. From the total 17 rhizosphere samples processed, we isolated 63 Bacillus spp. 29 (46%) of Huancavelica and 34 (54%) of Puno; 37 Actinomycetes, 32 (87%) of Huancavelica and 5 (13%) of Puno and 50 of Azotobacter spp. 37 (74%) of Huancavelica and 13 (26%) of Puno; in these two last cases a higher diversity was found in the rhizosphere of the region with acidic pH.

Keywords : Rhizosphere; Potato Crop; Azotobacter spp.; Bacillus spp.; Actinomycetes.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )