How do they cope with the situation when the caterpillars of beet armyworms, Spodoptera exigua, attack their host plant under different fertilization conditions?

College of Agronomy and Plant Protection, Qingdao Agricultural University, Qingdao, China
Shandong Peanut Research Institute, Qingdao, China
DOI
10.7287/peerj.preprints.2784v1
Subject Areas
Entomology
Keywords
biomass, phosphorus, nitrogen, fertilizer, enzyme
Copyright
© 2017 Wang et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Wang S, Ding T, Xu M, Zhang B. 2017. How do they cope with the situation when the caterpillars of beet armyworms, Spodoptera exigua, attack their host plant under different fertilization conditions? PeerJ Preprints 5:e2784v1

Abstract

Fertilizer with different ration of nitrogen (N) to phosphorus (P) could influence performance of plants including crops and vegetables. Spodoptera exigua is an important agriculture pest that has caused serious economic loss especially recent decades. In the present study, we explored that the response of host plants and S. exigua after S. exigua caterpillars damaged on the way of different level intensity and frequency under five fertilizer treatments with different ratio of N to P. The results indicated that fertilizer can significantly influence the interaction between host plants and caterpillars. Compensatory growth was detected under definite fertilizer with N : P = 3 : 1. Higher N proportion in fertilizer appears to contribute to maintain similar stem biomass in defoliated seedlings to control ones. Root biomass had almost no significant difference between defoliation and control, but it can not compensate under definite fertilizer. Higher proportion of N in fertilizer also contributed to enhance antioxidant enzymes activities: antioxidase catalase (CAT), superoxide dismutase (SOD), at low-level intensity caterpillars on host plants.However, when the herbivorous intensity was increasing, higher proportion of P in fertilizer seemed to play more important role on increase the activities of CAT and SOD. Higher phosphorus likely contributes to enhance acetylcholin esterase (AChE) activity at lower degree of defoliation, but higher nitrogen proportion could result in higher AChE activity at higher degree of defoliation. Higher content of nitrogen in definite range contributed to reduce the carboxylesterase (CarE) activity at high intensity within short-term defoliation. However, when defoliation intensity enhanced, the difference of CarE activity between fertilizer categories was small.

Author Comment

This is a submission to PeerJ for review.

Supplemental Information

Biomass of leaf, stem and root of rape seedlings fed by beet armyworm caterpillar under under diffrent fertilizer treatments

DOI: 10.7287/peerj.preprints.2784v1/supp-1

Enzymes activities of beet armyworm after defoliation under different fertilizer treatments

DOI: 10.7287/peerj.preprints.2784v1/supp-2