Abstract
Background: The active secondary metabolites of various Kalanchoe species are promising for controlling insects and other agricultural pests.
Objective: This study aimed to evaluate the mortality and immune responses of the leafcutter ant Atta sexdens (L.) after treatment with Kalanchoe ×laetivirens (Desc.) aqueous extract. The effects on an aquatic organism used as a bioindicator, Chironomus xanthus (Rempel), were also evaluated.
Methods: Different K. ×laetivirens concentrations were prepared by dilution in honey to assess the toxicity and determine the median lethal concentration (LC50) for A. sexdens workers. The haemocytes of workers treated with a sublethal concentration (0.005 g/mL) were counted.
Results: The plant extracts induced high mortality in A. sexdens workers. All concentrations, except 0.001 g/mL, increased mortality rates. The sublethal concentration negatively affected the immune system of A. sexdens workers 48 and 72 h after ingestion. The flavonoids 4″″-acetylsagittatin A, sagittatin A and the nucleosides uridine and adenosine were identified. The LC50 of the K. ×laetivirens (128.1 mg /L) was determined for the non-target organism, C. xanthus.
Conclusion: These natural compounds can be used in future research to plan alternative control strategies for leafcutter ants in forests and other agroecosystems.
Graphical Abstract
[http://dx.doi.org/10.1002/ps.3660] [PMID: 24115496]
[http://dx.doi.org/10.1007/978-3-662-10306-7]
[http://dx.doi.org/10.1007/s13595-016-0548-3]
[http://dx.doi.org/10.3389/fpubh.2016.00148] [PMID: 27486573]
[http://dx.doi.org/10.3390/insects11080532] [PMID: 32823868]
[http://dx.doi.org/10.1271/bbb.64.1310] [PMID: 10923811]
[http://dx.doi.org/10.11646/phytotaxa.460.1.6]
[http://dx.doi.org/10.1186/s41938-018-0101-9]
[http://dx.doi.org/10.1016/j.chemosphere.2009.05.002] [PMID: 19505710]
[http://dx.doi.org/10.3390/su10062023]
[http://dx.doi.org/10.1002/etc.3861] [PMID: 28636272]
[http://dx.doi.org/10.1002/etc.5620211133] [PMID: 12389933]
[http://dx.doi.org/10.1007/s10646-006-0117-x] [PMID: 17268839]
[http://dx.doi.org/10.1002/ps.5629] [PMID: 31595634]
[http://dx.doi.org/10.1002/ptr.2650080704]
[http://dx.doi.org/10.1016/0020-1790(85)90109-X]
[http://dx.doi.org/10.1080/01621459.1958.10501452]
[http://dx.doi.org/10.2307/2344317]
[http://dx.doi.org/10.1021/np960203u]
[http://dx.doi.org/10.4314/tjpr.v14i12.13]
[http://dx.doi.org/10.1016/j.bse.2010.09.019]
[http://dx.doi.org/10.1055/s-2006-962015] [PMID: 17262426]
[http://dx.doi.org/10.1177/1934578X0800300]
[http://dx.doi.org/10.3390/molecules191016240] [PMID: 25310150]
[http://dx.doi.org/10.3390/insects3020573] [PMID: 26466545]
[http://dx.doi.org/10.1093/jisesa/ieaa124] [PMID: 33159528]
[http://dx.doi.org/10.1038/s41598-020-63746-6] [PMID: 32321975]
[http://dx.doi.org/10.1080/14786419.2016.1247080] [PMID: 27764958]
[http://dx.doi.org/10.1002/ps.3895] [PMID: 25404103]
[http://dx.doi.org/10.1177/1179543318804783] [PMID: 30305796]
[http://dx.doi.org/10.1016/j.bjp.2016.10.001]
[http://dx.doi.org/10.1590/S0100-204X2006001000001]
[http://dx.doi.org/10.5902/198050981862]
[http://dx.doi.org/10.13102/sociobiology.v60i2.145-149]
[http://dx.doi.org/10.1007/s10646-019-02124-z] [PMID: 31696443]
[http://dx.doi.org/10.1016/j.yhbeh.2012.02.012] [PMID: 22381405]
[http://dx.doi.org/10.1016/j.bbi.2012.11.014] [PMID: 23207105]
[http://dx.doi.org/10.1111/j.1365-2435.2005.00979.x]
[http://dx.doi.org/10.1016/j.chemosphere.2011.05.039] [PMID: 21676429]
[http://dx.doi.org/10.1073/pnas.102176599]
[http://dx.doi.org/10.1111/jeb.12916] [PMID: 27272199]
[http://dx.doi.org/10.1054/tice.2001.0174] [PMID: 11469543]
[http://dx.doi.org/10.1016/j.envpol.2018.01.058] [PMID: 29414366]
[http://dx.doi.org/10.4103/2221-1691.271724]
[http://dx.doi.org/10.1186/1756-3305-4-8] [PMID: 21266078]
[http://dx.doi.org/10.1007/s00265-010-1090-1]
[http://dx.doi.org/10.1016/j.apsb.2017.05.001] [PMID: 28752026]