ABSTRACT
The main objective of this research was to evaluate the evapotranspiration rate of the chrysanthemum (Dendrantema grandiflora cv. Puritan), cultivated in pots under greenhouse conditions. In order to get best representative data, the experiment was conducted at the Triângulo farm located in Holambra municipality in São Paulo State of Brazil, employing traditional tillage practices. The water requirement of this crop was estimated by comparing the chrysanthemum pot weight, during five different development stages of crop, with the evaporation from a modified class A pan and from a modified atmometer, and with the crop leaf area index. In each stage (treatment) five plants were evaluated, resulting in five repetitions per treatment. For a more representative weather conditions, the measurements were performed from August to December 1995 and from February to June 1996, on a two-month interval basis. A multiple regression analysis of the results showed that there is a statistical correlation between measured and estimated data, and also that the chrysanthemum evapotranspiration rate can be estimated considering the leaf area in each development stage of crop.
Key words:
Dendrantema grandiflora; evapotranspiration rate; atmometer; modified class; A pan