ARAÚJO, Thiago Silva.; http://lattes.cnpq.br/1093165605979612; ARAÚJO, Thiago Silva.
Résumé:
Plants cultivated within and outside the protected area (a covered shelter
with plastic) during the same growing period, under different meteorological
conditions occurred due to the plastic covering of the shelter. This research is
conducted in protected (AE) and natural (AN) ambients. The objective of this work is
to evaluate the development (growth) and quantity the effect of the meteorological
elements on the growth of the Iettuce crop under to different ambients and in two
different epochs. The research was conducted at the "Empresa Estadual de
Pesquisa Agropecuária da Paraíba 8. A. - EMEPA", during the periods of 30!05 to
08/08/2007 and 10109 to 221112007, periods of winter and spring using two cultivars
of Iettuce: "Elba" and "Americana Irene". The mean air temperatures in AE were
higher than those in AN during both the experiments (21 .6 C and 228 C.
respectively). The values of the mean daily relative humidity obtained in AN were
more than those in AE during both the experiments (921% in Exp.1 and 813% in
Exp.2). The levels of the photosynthetically active radiation (PAR) within the
protected ambient (AE) accompanied the same pattern as the PAR in AN but with
less intensity, due to the absorption of part of the PAR by the polyethelene cover.
The protected ambient has favourable micro-climate to the crop growth, anticipating
the harvest of the lettuce by one week in both the experiments. During the winter
(Exp.1) the crop growth, development and production were higher in AE than in AN.