Correlation-based network analysis of the influence of Bemisia tabaci feeding on photosynthesis and foliar sugar and starch composition in soybean

Authors: SCHUTZE, I.X. - University Of São Paulo; YAMAMOTO, P.T. - University Of São Paulo; MALAQUIAS, J.B. - Sao Paulo State University (UNESP); Herritt, Matthew; Merten, Paul; Thompson, Alison; Naranjo, Steven

Submitted to: Insects
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/23/2021
Publication Date: 1/5/2022
Citation: Schutze, I., Yamamoto, P., Malaquias, J., Herritt, M.T., Merten, P., Thompson, A.L., Naranjo, S.E. 2022. Correlation-based network analysis of the influence of Bemisia tabaci feeding on photosynthesis and foliar sugar and starch composition in soybean. Insects. 13(1). Article 56. https://doi.org/10.3390/insects13010056.
DOI: https://doi.org/10.3390/insects13010056

Interpretive Summary: Whiteflies (Bemisia tabaci) have become more problematic in soybean production in Brazil in recent years. Assessing the damage from whitefly feeding is difficult because many other pests also feed on the crop. Controlled greenhouse studies were conducted to examine the effect of variable levels of whitefly infestation on sugars, starches and various photosynthetic variables in soybean leaves during vegetative and reproductive phenological stages. The goal was to define the optimal plant factors that might be associated with whitefly feeding. In general, we found that nymphs were more abundant during the vegetative stage and that starch in leaves was strongly correlated with nymph density. A strong positive correlation between fructose and nymph density was observed for infestation levels during the vegetative stage. Among the photosynthetic parameters, the turn-over number N, was negatively correlated with higher nymph densities. Whitefly feeding affected the plant’s physiology and its interaction is reflected in part by the relationships among photosynthetic parameters as well as the levels of sugars and starch. These associations might be useful for assessing whitefly damage to soybeans in the field.

Technical Abstract: Bemisia tabaci (MEAM1) represents a species of economic importance in soybean. One of the obstacles to the management of B. tabaci is the quantification of damage by the pest because damage is indirectly inferred through losses in productivity. The objective of this study was to characterize the influence of B. tabaci feeding on soybean by assessing effects on photosynthetic parameters and the sugar and starch content of soybean leaves. The goal was to identify the optimal parameter to directly quantify pest damage on crop yield. Correlation networks were created among data on sugar content (fructose, glucose, and sucrose), starch and photosynthetic parameters (initial fluorescence, performance index on absorption basis, and turn-over number), and the number of nymphs at each of three infestations level (low, medium, and high) during both the vegetative and reproductive stage of the crop. In general, nymphs were more abundant during the vegetative stage. Starch content was strongly correlated with nymph density. A strong positive correlation was observed between fructose and nymph density during the vegetative stage. Among the photosynthetic parameters, the turn-over number N was positively correlated with nymph density at a low-infestation level and negatively correlated with nymphs when they occurred at a high-infestation level. B. tabaci feeding affected the plant’s physiology and its interaction is reflected in part by the relationships among photosynthetic parameters as well as the levels of sugars and starch. This understanding might be useful in developing better monitoring tools for pest management.