Efetividade de rizóbios isolados de solos da região Nordeste do Brasil na fixação do N2 em amendoim (Arachis hypogaea L.)

Effectiveness of rhizobia on peanut (Arachis hypogeae) nitrogen fixation, isolated from semi-arid soils of northeastern Brazil. Nitrogen fixation by efficient native rhizobia strains may contribute to increase grain yield and to promote economy of nitrogen fertilizers in Brazilian semi-arid region. A greenhouse experiment was carried out in order to evaluate the nitrogen fixation efficiency of four peanut genotypes inoculated with rhizobia isolated from northeastern Brazil. The IAC Tatu cultivar established the most efficient symbiosis, while BR1 depended of N fertilizers application and showed high levels of total N in shoots only with S11 isolate. The majority of the rhizobia isolates established efficient symbiosis and N accumulation with IAC Tatu, Sertao and Embrapa 142-L7 genotypes, when compared to N mineral treatment. The results showed that native rhizobia can promote good nodulation, total N and dry matter yield, and may be used as specific inoculant for peanut in soils of Brazilian semi-arid region.

[1]  I. Akobundu,et al.  Nodulation and estimation of symbiotic nitrogen fixation by herbaceous and shrub legumes in Guinea savanna in Nigeria , 1996, Biology and Fertility of Soils.

[2]  C. D. S. Santos,et al.  Efeito da fertilização com fósforo, potássio e magnésio em jacatupé infectado com rizóbio em um Latossolo álico , 1999 .

[3]  M. Hungria,et al.  Avaliação de cultivares de soja quanto à fixação biológica do nitrogênio , 1998 .

[4]  L. M. Martins,et al.  Growth characteristics and symbiotic efficiency of rhizobia isolated from cowpea nodules of the north-east region of Brazil , 1997 .

[5]  E. Malavolta,et al.  Avaliação do estado nutricional das plantas: princípios e aplicações , 1997 .

[6]  N. Stamford,et al.  Symbiotic Effectiveneß of Several Tropical Bradyrhizobium Strains on Cowpea under a Long-Term Exposure to Nitrate: Relationships between Nitrogen Fixation and Nitrate Reduction Activities , 1995 .

[7]  J. Thies,et al.  Subgroups of the Cowpea Miscellany: Symbiotic Specificity within Bradyrhizobium spp. for Vigna unguiculata, Phaseolus lunatus, Arachis hypogaea, and Macroptilium atropurpureum , 1991, Applied and environmental microbiology.

[8]  R. Date,et al.  Rhizobium screening of Stylosanthes species for effectiveness in nitrogen fixation , 1979 .

[9]  W. Schwartz.  J. M. Vincent, A Manual for the Practical Study of the Root-Nodule Bacteria (IBP Handbuch No. 15 des International Biology Program, London). XI u. 164 S., 10 Abb., 17 Tab., 7 Taf. Oxford-Edinburgh 1970: Blackwell Scientific Publ., 45 s , 1972 .

[10]  J. P. Cooper.  Some Concepts and Methods in Sub-Tropical Pasture Research. , 1965 .

[11]  J. M. Bremner.  Total Nitrogen 1 , 1965 .