poster - International Conference of Agricultural Engineering

4
Height of seedlings (cm)
35
30
25
20
15
10
5
y = -0,0042x 2 + 0,9003x - 16,201
R 2 = 0,9622
y = -0,0147x 2 + 2,728x - 94,055
R 2 = 0,8967
Solo
Formosa
0
60 70 80 90 100
Available water in soil (%vol)
Figure 1. Height of seedling of papaya Solo and Formosa group as a function of available water in soil
The increase in soil moisture stimulated the development of stem diameter of seedlings of
both genotypes (Figure 2). Genotype in Solo, the stem diameter increased linearly to the level of
0.1364 mm by increasing unitary of soil moisture in relation to field capacity reaching the highest
value of 12.8 mm in the soil with moisture kept equal to 100% field capacity. This treatment
exceeded by 74.8, 47.1, 20.8 and 11.9% regarding irrigation to maintain soil moisture levels of 60,
70, 80 and 90% field capacity, respectively. The stem diameter of genotype Formosa increased as a
function of moisture reaching the maximum value of 10.47 mm with treatment maintained the
moisture de100% of field capacity, however, the deficit and excess water affected the number of
seedlings of both genotypes. These higher results observed in the genotypes Formosa and Solo
were above 7.6, 7.4, 7.9 and 9.0 mm obtained by Cavalcante et al. (2010), Negreiros et al. (2005),
Medeiros et al. (2008) and Araújo et al. (2010). However were lower than 12 mm and 16.4
mm recorded by Souza et al. (2007) and Melo et al. (2007) with cultivars Formosa and Baixinho
Santa Amalia, respectively. The stem diameter of seedlings Solo and Formosa was greater than 9.79
cm observed by Mahouachi et al. (2006) with seedlings of the cultivar Baixinha Santa Amalia,
subjected to water stress.