Is the Performance of a Specialist Herbivore Affected by Female Choices and the Adaptability of the Offspring?

Abstract

The performance of herbivorous insects is related to the locations of defenses and nutrients found in the different plant organs on which they feed. In this context, the females of herbivorous insect species select certain parts of the plant where their offspring can develop well. In addition, their offspring can adapt to plant defenses. A system where these ecological relationships can be studied occurs in the specialist herbivore, Tuta absoluta, on tomato plants. In our experiments we evaluated: (i) the performance of the herbivore T. absoluta in relation to the tomato plant parts on which their offspring had fed, (ii) the spatial distribution of the insect stages on the plant canopy and (iii) the larval resistance to starvation and their walking speed at different instar stages. We found that the T. absoluta females preferred to lay their eggs in the tomato plant parts where their offspring had greater chances of success. We verified that the T. absoluta females laid their eggs on both sides of the leaves to better exploit resources. We also observed that the older larvae (3rd and 4th instars) moved to the most nutritious parts of the plant, thus increasing their performance. The T. absoluta females and offspring (larvae) were capable of identifying plant sites where their chances of better performance were higher. Additionally, their offspring (larvae) spread across the plant to better exploit the available plant nutrients. These behavioral strategies of T. absoluta facilitate improvement in their performance after acquiring better resources, which help reduce their mortality by preventing the stimulation of plant defense compounds and the action of natural enemies.

Assessing the spatial distribution of Tuta absoluta (Lepidoptera: Gelechiidae) eggs in open‐field tomato cultivation through geostatistical analysis

“…[10][11][12][13] Therefore, several studies have been published to estimate the climate sustainability and risk assessment for the worldwide invasion and potential spread of T. absoluta on a global scale. 1,14 Other research has focused on spatial distribution within the plant canopy [15][16][17] and between-plant distribution under greenhouse conditions. 18 However, there is a lack of research on the spatial distribution of T. absoluta in open-field tomato cultivation.…”

Resistant and susceptible tomato genotypes have direct and indirect effects on Podisus nigrispinus preying on Tuta absoluta larvae

“…Each tomato branch was infested with five third-fourth-instar T. absoluta larvae using a fine brush. First and second instar larvae mine the leaves, feeding on the mesophyll, whereas older larvae usually emerge from their mines and search for young apical leaves, stems or fruits on which they complete larval development (Desneux et al, 2011;Galdino et al, 2015). The latter may represent a period of susceptibility to predation by natural enemies in the field.…”

“…The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has long been considered one of the major pests of tomatoes, Solanum lycopersicon L., in South America. It has also become a major threat to tomato production in Europe, Africa, and Eurasia after its recent introduction to these regions (Desneux et al, 2010(Desneux et al, , 2011Galdino et al, 2015). Larvae of T. absoluta can injure both the leaves and fruits of tomatoes, ultimately leading to reductions in yield (Desneux et al, 2011;Tropea Garzia et al, 2012;Galdino et al, 2015).…”

Biological performance and oviposition preference of tomato pinworm Tuta absoluta when offered a range of Solanaceous host plants

“…The tomato pinworm Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) is currently considered as the most devastating invasive lepidopteran pest of tomato crops worldwide 5 – 9 . Tuta absoluta is native to South America and is a specialist predator of Solanaceae 5 , 8 , 10 . The destructive effect of these insects is due to the formation of “mines” within the leaves and the formation of galleries in the stems, fruits and flowers, which can result in losses of up to 100% in tomato crops 11 .…”