Welcome

This blog will showcase the GlobalChangeBiology project.

Comments

Post a Comment

Popular posts from this blog

Why was the invasion risk of Tuta absoluta underestimated?

Image
The capacity to assess invasion risk from potential crop pests before invasion of new regions globally would be invaluable, but this requires the ability to predict accurately their potential geographic range and relative abundance in novel areas. This may be unachievable using de facto standard correlative methods as shown for the South American tomato pinworm Tuta absoluta , a serious insect pest of tomato native to South America. Its global invasive potential was not identified until after rapid invasion of Europe, followed by Africa and parts of Asia where it has become a major food security problem on solanaceous crops. Early prospective assessment of its potential range is possible using physiologically based demographic modeling that would have identified knowledge gaps in T. absoluta biology at low temperatures. Physiologically based demographic models (PBDMs) realistically capture the weather-driven biology in a mechanistic way allowing evaluation of invasive risk in novel ar...
Read more

Why radiation use efficiency is lower in super high-density than in high-density olive orchards

Image
We quantified the photosynthetically active radiation (PAR) interception in a high-density (HD) and a super high-density (SHD) or hedgerow olive system, by measuring the PAR transmitted under the canopy along transects at increasing distance from the tree rows. Transmitted PAR was measured every minute, then cumulated over the day and the season. The frequencies of the different PAR levels occurring during the day were calculated. SHD intercepted significantly but slightly less overall PAR than HD (0.57 ± 0.002 vs. 0.62 ± 0.03 of the PAR incident above the canopy) but had a much greater spatial variability of transmitted PAR (0.21 under the tree row, up to 0.59 in the alley center), compared to HD (range: 0.34–0.43). This corresponded to greater variability in the frequencies of daily PAR values, with the more shaded positions receiving greater frequencies of low PAR values. The much lower PAR level under the tree row in SHD, compared to any position in HD, implies greater self-shading...
Read more

Impact of low temperature and host plant on Tuta absoluta

Image
Alternative host plants are among the key factors influencing the spread of invasive pests because they are utilized as a food source and provide shelter in unfavorable conditions. The South American tomato pinworm (SATP), Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), has a high behavioral and physiological plasticity enabling it to rapidly spread in several countries. Among the multiple strategies used by SATP in the invasion process is the use of alternative host plants including black nightshade (BNS), Solanum nigrum L. (Solanaceae), a perennial plant widely distributed across all habitats worldwide. Besides the life table and behavioral parameters of SATP on tomato, its survival and reproduction in low temperatures on alternative host plants should be assessed to evaluate the likely spread in temperate regions with harsh winters. In our study, comparing solanaceous species through generations, the primary difference was in the mean generation time with SATP reared on BNS, whe...
Read more