Herbivory on Handroanthus ochraceus (Bignoniaceae) along a successional gradient in a tropical dry forest

Abstract

This study determined the temporal patterns of herbivory on Handroanthus ochraceus (Cham.) Mattos (Bignoniaceae) along a successional gradient in a seasonally dry tropical forest (SDTF) in southeastern Brazil. We assessed the diversity of free-feeding herbivore insects (sapsuckers and leaf-chewers), leaf herbivory rates, leaf nitrogen content, phenolic compounds, and spider abundance through the rainy season in three different successional stages (early, intermediate, and late). Sampling was conducted in December, at the beginning of the rainy season (with fully expanded young leaves), February (mid-aged leaves), and April, at the end of rainy season (old leaves). Fifteen reproductive trees of H. ochraceus were sampled per successional stage in each month of sampling. Herbivore diversity was highest in the early stage of succession, but herbivory rates were highest in the intermediate and late stages. This result was probably related to differences in herbivore community composition and leaf quality across successional stages. The highest herbivore abundance was found in April in the early successional stage. In addition, we found low levels of herbivory in the intermediate and late successional stages in the second half of the rainy season. For each successional stage, leaf nitrogen content decreased through the rainy season, whereas the concentration of phenolic compounds increased. For the intermediate and late successional stages, the temporal changes that took place as the rainy season progressed corroborated the following hypotheses postulated for SDTFs: (1) both the abundance of chewing insects and herbivory rates decreased, (2) the abundance of natural enemies (i.e., spiders) increased, and (3) leaf quality decreased. These results suggest that the described herbivory patterns are robust for advanced successional stages (intermediate and late) of the SDTFs, but may not apply to early successional stages of these forests.

Dispersal capacity of fruit fly parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae) in irrigated coffee plantations

“…The local climate is considered tropical semiarid (Koppen classification) and is characterized by dry winters. The average temperature in the region is 24 °C, with a mean elevation of 500 m and an average annual precipitation of 871 mm (Silva et al, 2012). The D. longicaudata used in the experiments were reared using 3 rd stage larvae of C. capitata as hosts.…”

Variação nas concentrações de compostos fenólicos e nas taxas de herbivoria em Aspidosperma pyrifolium Mart. em áreas antropizadas de Caatinga

“…Entretanto, esse fenômeno varia de acordo com a espécie e o ambiente onde a planta se desenvolve. Silva (2012), no seu estudo em uma floresta sazonal tropical seca, no estado de Minas Gerais, usando folhas de Ipê amarelo (Handroanthus ochraceus Cham. ), observou variações nas taxas de nitrogênio durante a estação chuvosa, que diminuíam gradativamente durante essa estação, sendo o mesmo observado nas áreas impactadas, quando, em fevereiro apresentou a maior concentração de nitrogênio foliar, seguido de uma queda nestes valores em abril e junho.…”

Tree diameter growth for three successional stages of Tropical Dry Forest in Minas Gerais, Brazil

“…Moreover, the lowest MAI values for the late stage are in the 50 to 65 cm class, given that trees with these dimensions are at a mature stage of flowering and fruiting where the allocation of nutrients is for reproduction and not growth (Fredericksen, Contreras & Pariona, 2001 Some specific characteristics of these species can also influence their dominance and high MAI's. Handroanthus ochraceus is a species with phenolic compounds in the leaves and, according to Silva, Espírito-Santo & Melo (2011), the percentage of herbivory is higher in the intermediate and late stages and lower in the early stage for MSSP. Myracrodruon urundeuva produces a chemical barrier formed by tannins, which are compounds known to have fungicidal and insecticidal effects.…”