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Print version ISSN 0006-8705On-line version ISSN 1678-4499

Bragantia vol.35 no.1 Campinas  1976 

Temperatura-base para alface cultivar "white boston", em um sistema de unidades térmicas


Base temperature for lettuce in a heat-unit system



O. BruniniI, *; R. S. LisbãoII; J. B. Bernar-DIII, *; J. B. FornasierII, *; M. J. Pedro JúniorIII, *

ISeção de Climatologia Agrícola
IISeção de Hortaliças Diversas
IIISeção de Climatologia Agrícola, Instituto Agronômico




Através de um sistema de unidades térmicas, estudou-se o efeito da temperatura média do ar sobre o desenvolvimento de alface (Lactuca sativa L.), cultivar "white boston".
Os resultados evidenciaram que a temperatura-base de desenvolvimento dessa hortaliça varia com o estádio de desenvolvimento da cultura, sendo igual a 6°C para a fase germinação-transplante, e 10ºC para a fase transplante-colheita.
Observou-se que o desenvolvimento da planta em função da temperatura média do ar não é linear, pois atinge um máximo em torno de 22°C e após isso a taxa do desenvolvimento é decrescente.


The effect of mean air temperature on the development of lettuce (Lactuca sativa L.) variety White Boston was determined in a heat-unit system.
The results showed that the base temperature is function of the stage of development of the crop. The base temperature for the phase: emergence-transplant was 6°C and for the phase transplant-harvest was 10°C.
It was observed that there is not a linear relationship between crop development and mean air temperature because the growth rate had a maximum at 22°C and it decreased after this value.



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Recebido para publicação em 12 de janeiro de 1976.



* Com bolsa de suplementação do C.N.Pq.

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