Screening Upland Rice Genotypes for Zinc Use Efficiency.

Screening Upland rice Genotypes for Zinc Use Efficiency

 

A. S. Nacente and N. K. Fageria

National Rice and Bean Research Center of Embrapa (Empresa Brasileira de Pesquisa Agropecuaria), Caixa Postal 179, Santo Antonio de Goiás, GO, CEP 74001-970, Brazil.

ABSTRACT

Zinc (Zn) deficiency is very common in annual crops grown on Brazilian Oxisols. A greenhouse experiment was conducted to evaluate Zn us efficiency of 20 upland rice genotypes. The Zn levels used were 0 mg kg^-1 (natural level of the soil) and 20 mg kg^-1 of soil applied with ZnSO₄. Zinc X genotype interactions were significant for grain yield, panicle number, panicle length, root dry weight and specific root length, indicating different responses of genotypes with the variation of Zn levels and selection for Zn use efficiency is necessary at low as well as at higher Zn rates. Based on Zn use efficiency index, 11 genotypes were classified as efficient and 9 were classified as moderately efficient. Most Zn efficient genotypes were BRA 01596, BRA 042156, BRA 052053, BRA Primavera and BRA 01506. Most inefficient genotypes in Zn use efficiency were BRA 042094, BRA 052045, BRA 052034, and BRA 052023. Grain yield and most of the yield attributing characters having Zn X genotype interactions significant, which indicated that genotypes responded differently under two Zn levels. Thus genotype selection is an important strategy for upland rice production in Brazilian Oxisols.