Laboratory and field trials of Green Guard® (Metarhizium anisopliae var. acridum) (Deuteromycotina: Hyphomycetes) against the oriental migratory locust (Locusta migratoria manilensis) (Orthoptera: Acrididae) in China

Biology and Transformation of the Migratory Locust Locusta migratoria manilensis Meyen (Orthoptera: Acrididae) at Several Laboratory Population Density Levels. The migratory locust, Locusta migratoria manilensis Meyen (Orthoptera: Acrididae) is one of insect pests in Indonesia that undergoes a unique polymorphic biology. The locust develops a transformation phase which is triggered mainly by high population density. Its recent outbreaks in several regions of Indonesia cause major concern and control strategies must be developed to strengthen control efforts in the future. Its unique polymorphic phenomenon, therefore, must be investigated thoroughly for the basis of management of the outbreak. Due to its agility and its long range flying ability, the most realistic technique to study behavioral and morphological change of the locust is in controlled condition at a laboratory or a green house facility. The experiment was aimed to study effects of colony densities on the biology and transformation process of the migratory locust. More specifically, the experiment was to study effects of population density on the feeding activity, mortality rate, and the ratio of F/C and E/F of the migratory locust L. migratoria manilensis. The population densities were simulated in colonies at 2, 5, 10, 20, dan 30 couples per cage (cage size: 45x45x90 cm) reared in a green house. Results of the experiment show that, in general, higher densities of the migratory locust colonies tended to feed more rigorously than those of the less dense colonies. The locust remained in solitary phase at the density of 2-5 couples per cage whereas the transient phase occured at the density of 10-20 couples per cage. The colonies transformed to gregarious stage when their densities were 30 couples per cage or higher. Mortality percentage tended to be higher at colonies with higher density, especially for the third instar of the migratory locust.

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Effects of the Entomopathogenic Fungus Metarhizium anisopliae on the Mortality and Immune Response of Locusta migratoria

Insects ◽

10.3390/insects11010036 ◽

2019 ◽

Vol 11 (1) ◽

pp. 36 ◽

Cited By ~ 5

Author(s):

Wuji Jiang ◽

Yifan Peng ◽

Jiayi Ye ◽

Yiyi Wen ◽

Gexin Liu ◽

...

Keyword(s):

Immune Response ◽

Entomopathogenic Fungi ◽

Metarhizium Anisopliae ◽

Entomopathogenic Fungus ◽

Insect Pests ◽

Locusta Migratoria ◽

Management Strategies ◽

Sod Activity ◽

Immune Related Genes ◽

Locusta Migratoria Manilensis

Entomopathogenic fungi are the key regulators of insect populations and some of them are important biological agents used in integrated pest management strategies. Compared with their ability to become resistant to insecticides, insect pests do not easily become resistant to the infection by entomopathogenic fungi. In this study, we evaluated the mortality and immune response of the serious crop pest Locusta migratoria manilensis after exposure to a new entomopathogenic fungus strain, Metarhizium anisopliae CQMa421. M. anisopliae CQMa421 could effectively infect and kill the L. migratoria adults and nymphs. The locust LT50 under 1 × 108 conidia/mL concentration of M. anisopliae was much lower than that under conidial concentration 1 × 105 conidia/mL (i.e., 6.0 vs. 11.2 and 5.0 vs. 13.8 for adults and nymphs, respectively). The LC50 (log10) of M. anisopliae against locust adults and nymphs after 10 days was 5.2 and 5.6, respectively. Although the number of hemocytes in L. migratoria after exposure to M. anisopliae did not differ with that in the controls, the enzymatic activity of superoxide dismutase (SOD) and prophenoloxidase (ProPO) did differ between the two treatments. The activities of both SOD and ProPO under the M. anisopliae treatment were lower than that in the controls, except for the ProPO activity at 72 h and the SOD activity at 96 h. Further, the expression of the L. migratoria immune-related genes defensin, spaetzle, and attacin differed after exposure to M. anisopliae for 24 h to 96 h. Taken together, this study indicated that infection with M. anisopliae CQMa421 could cause the death of L. migratoria by interacting with the immune responses of the host, demonstrating that this fungal strain of M. anisopliae can be an efficient biocontrol agent against L. migratoria.

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Identification and characterization of a gene encoding a UBX domain-containing protein in the migratory locust,Locusta migratoria manilensis

Insect Science ◽

10.1111/j.1744-7917.2012.01548.x ◽

2012 ◽

Vol 20 (4) ◽

pp. 497-504

Author(s):

Zheng-Bo He ◽

Yu Xie ◽

Feng-Ling Si ◽

Bin Chen

Keyword(s):

Locusta Migratoria ◽

Gene Encoding ◽

Migratory Locust ◽

Locusta Migratoria Manilensis ◽

Identification And Characterization

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Periodic temperature-associated drought/flood drives locust plagues in China

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2008.1284 ◽

2008 ◽

Vol 276 (1658) ◽

pp. 823-831 ◽

Cited By ~ 35

Author(s):

Zhibin Zhang ◽

Bernard Cazelles ◽

Huidong Tian ◽

Leif Christian Stige ◽

Achim Bräuning ◽

...

Keyword(s):

Global Warming ◽

Locusta Migratoria ◽

Climatic Variability ◽

Low Frequency ◽

Migratory Locust ◽

The Past ◽

Yangtze Delta Region ◽

Periodic Temperature ◽

Locusta Migratoria Manilensis ◽

Past Millennium

Global warming is currently of great concern. Yet the ecological effects of low-frequency climate variations remain largely unknown. Recent analyses of interdecadal variability in population abundance of the Oriental migratory locust ( Locusta migratoria manilensis ) in China have revealed negative associations with temperature and positive associations with Yangtze drought and flood frequencies during the past millennium (AD 957–1956). In order to shed new light on the causal relationships between locust abundance, floods, droughts and temperature in ancient China, we used wavelet analysis to explore how the coherencies between the different variables at different frequencies have been changed during the past millennium. We find consistent in-phase coherencies between locusts and drought/flood frequencies, and out-of-phase coherencies between locusts and temperature and between drought/flood and temperature at period components of 160–170 years. Similar results are obtained when historical data of drought/flood frequencies of the Yangtze Delta region are used, despite flood data showing a weak and somewhat inconsistent association with other factors. We suggest that previously unreported periodic cooling of 160–170-year intervals dominate climatic variability in China through the past millennium, the cooling events promoting locust plagues by enhancing temperature-associated drought/flood events. Our results signify a rare example of possible benign effects of global warming on the regional risk of natural disasters such as flood/drought events and outbreaks of pest insects.

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