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Outcrossing rates and inbreeding coefficients in rubber trees (Hevea brasiliensis(Willd. ex Adr. de Juss.) Müeller Arg.)^*

João Rodrigues de Paiva^I; Paulo Yoshio Kageyama^II; Roland Vencovsky^III

^IEMBRAPA/CPAA, Caixa Postal 319, 69048-660 Manaus, AM, Brasil. Send correspondence to J.R.P.
^IIDepartamento de Ciências Florestais, ESALQ-USP, Caixa Postal 9, 13418-900 Piracicaba, SP, Brasil
^IIIDepartamento de Genética, ESALQ/USP, Caixa Postal 83, 13418-900 Piracicaba, SP, Brasil

ABSTRACT

Electrophoretic analyses were carried out in starch gel with young leaves of rubber trees of two native populations from the state of Acre, Brazil. The parameters evaluated in this study were obtained from the expected (H_e) and obsrved (H₀) heterozygote frequencies. Natural outcrossing rates (t) and inbreeding coefficients in populations (f) were estimated. Estimated f was 19.30% and 21.34% for populations 1 and 2, with an average of 21.84% while estimated t was 64.15%.

Keywords: outcrossing rates; inbreeding coefficients; rubber trees; Revea brasiliensis.

REFERENCES

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* Part of a thesis presented by J.R.P. to ESALQ/USP in partial fulfillment of the requirements for the Doctoral degree.