Eficiência de métodos de amostragem e influência da cultura anterior na incidência de insetos na soja

Abstract

An experiment was conducted with the objective of omparing the efficiency of three different sampling methods and the occurrence of insects in succession to fallow and oat and wheat crops, in soybean culture in lowland conditions. A completely randomized design was used, with ten replications, in a 3x3 factorial scheme and three different succession strategies were evaluated (area of succession to fallow and wheat and oat crops) and three sampling methods (vertical batting cloth, net - weeping and visual examination), during the reproductive period of the culture between the stages R1 and R7, making a total of ten repetitions. Statistical analyzes were performed according to the PROC GLIMMIX of the SAS statistical program and the comparison between the averages was made using the LSD test (Least Significant Difference), protected by the global F test (p ≤ 0.01). The results showed that there was no interaction between the factors, thus, the means of the main effects of different succession strategies and sampling methods were compared. In relation to different succession strategies, there was a significant difference for the total variable of insects and lepidoptera. The total number of insects was higher in cultivation after fallow than after wheat and oat crops. For lepidopteros, the number of insects after the cultivation of oats was lower than after the fallow. The vertical tapping cloth and visual examination are more efficient for the total collection of insects and for lepidopteros, when compared to the sweep net, in sampling systems in the Integrated Soy Pest Management.