Abstract:
Forestry expertise and plantations managers are struggling to find cheaper and sustainable solutions to contain the
losses caused by Leptocybe invasa in the last nine years on the forest stands in Mozambique. Aiming to help find a solution in the
control of L. invasa early in the nursery, we conducted an experimental trial at the Niassa Forestry company nursery, located in
the Niassa province, northern Mozambique in February 2015. Three insecticides: Acetamiprid, Thiamethoxam, Imidacloprid,
with and without adherent and pH regulator were tested. The experiment had seven treatments including the control. The number
of seedlings infested by the gall wasp were assessed 15, 30, 45 and 60 days after the seeds were sown in the nursery. Data were
analysed in R package. Normality and homogeneity of variances were tested through Shapiro-Wilk and Bartlett's tests
respectively. Analysis of Variance (ANOVA) and parametric means test (Tukey-HSD), were used to assess whether there was
difference among the treatments. Results showed difference between treatments at 0.01% of significance after 15, 30 and 45 days
and at 5% in the 60 days after sowing. With less seedlings infested by the gall wasp, Imidacloprid with and without adherent was
almost superior compared to all other pesticides in all assessment. The use of adherent and pH regulators negatively affected the
performance of insecticides, except in the Imidacloprid. This study findings should not however, be overall generalized, instead,
more research can be conducted to verify the consistency of these results before being widely implemented.
