Beetles, toxic spray

The activities of 4 ecdysteroids (20E 1-1, E 2-1, polB 2-6 and poststerone 2-11 ) have been compared after spraying on to the food (potato leaves) of the Colorado beetle, Leptinotarsa decemlineata [182], Surprisingly, poststerone gave a high level of toxicity. 

Quinolizidine alkaloids, pure or in mixtures of plant extract, can be used to protect plants against noxious insects. Scientific data have shown that quinolizidine alkaloids play a role in the resistance of some lupine varieties to the pea aphid (Acyrthosiphon pisum Harris) due to their ability to inhibit the development of this pest population. Evidence also points out that alkaloid extracts have an important influence on the feeding and development of larvae and on potato beetle mortality. Researchers concluded that the toxicity and restricted larval development was correlated with alkaloid content. In this research, the strongest action of the extract contained 1.6-3.3% alkaloids. Spraying potatoes with lupine extract seems to be... 

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