Insecticidal Activities of Alkaloids Extracted from Poisonous Plants

[Objective] Insecticidal activities of alkaloids extracted from 12 poisonous plants in Changbai Mountain were studied in the paper,to provide the basis for development and utilization of poisonous plants in Changbai Mountain.[Method] Leaf disc method was used to study the effects of alkaloids extracted from 12 poisonous plants on the growth and development of 3-5 instars of cabbage worm （Pieris rapae） and their antifeedant activities.[Result] The effects of alkaloids extracted from different poisonous plants on the growth and development of cabbage worm were also different.Five treatments of alkaloids extracted from Sophora flavescens,Datura stramonium L.,Arisaema amurense Maxim.,Veratum dahuricum Loes.and Tripterygium regelii Spragne et Takeda made the weight of test insects gradually decrease and finally die;the alkaloid treatments of Pueraria lobata （Willd.） Ohwi,Aconitum kusnezoffii Reichb.,Cimicifuga dahurica （Turcz.） Maxim.and Corydalis ambigua Schleeht.could make cabbage worm pupate ahead of time,but the pupa state was deformed;the antifeedant rates of cabbage worm after the treatments of P.lobata,A.kusnezoffii,C.dahurica,A.amurense,V.dahuricum and C.ambigua for 48 h were all over 90%,and the antifeedant rates of C.dahurica and C.ambigua were the highest as 100%.[Conclusion]The reports on the insecticidal activities of five poisonous plants including P.lobata,A.kusnezoffii,C.dahurica,C.ambigua and A.amurense are rare,and they have important values on the development of botanical pesticides.

Prospects and Problems for Identification of Poisonous Plants in China using DNA Barcodes

Objective Poisonous plants are a deadly threat to public health in China. The traditional clinical diagnosis of the toxic plants is inefficient, fallible, and dependent upon experts. In this study, we tested the performance of DNA barcodes for identification of the most threatening poisonous plants in China. Methods Seventy-four accessions of 27 toxic plant species in 22 genera and 17 families were sampled and three DNA barcodes （motK, rbcL, and ITS） were amplified, sequenced and tested. Three methods, Blast, pairwise global alignment （PWG） distance, and Tree-Building were tested for discrimination power. Results The primer universality of all the three markers was high. Except in the case of ITS for Hemerocollis minor, the three barcodes were successfully generated from all the selected species. Among the three methods applied, Blast showed the lowest discrimination rate, whereas PWG Distance and Tree-Building methods were equally effective. The ITS barcode showed highest discrimination rates using the PWG Distance and Tree-Building methods. When the barcodes were combined, discrimination rates were increased for the Blast method.

Beauty of the beast: anticholinergic tropane alkaloids in therapeutics

Tropane alkaloids(TAs)are among the most valued chemical compounds known since pre-historic times.Poisonous plants from Solanaceae family(Hyoscyamus niger,Datura,Atropa belladonna,Scopolia lurida,Mandragora officinarum,Duboisia)and Erythroxylaceae(Erythroxylum coca)are rich sources of tropane alkaloids.These compounds possess the anticholinergic properties as they could block the neurotransmitter acetylcholine action in the central and peripheral nervous system by binding at either muscarinic and/or nicotinic receptors.Hence,they are of great clinical impor-tance and are used as antiemetics,anesthetics,antispasmodics,bronchodilator and mydriatics.They also serve as the lead compounds to generate more effective drugs.Due to the important pharmacological action they are listed in the WHO list of essential medicines and are available in market with FDA approval.However,being anticholinergic in action,TA medication are under the suspicion of causing dementia and cognitive decline like other medications with anticholinergic action,interestingly which is incorrect.There are published reviews on chemistry,biosynthesis,phar-macology,safety concerns,biotechnological aspects of TAs but the detailed information on anticholinergic mecha-nism of action,clinical pharmacology,FDA approval and anticholinergic burden is lacking.Hence the present review tries to fill this lacuna by critically summarizing and discussing the above mentioned aspects.

Nitrogen addition overrides the effects of Stellera chamaejasme litter on the growth of Leymus chinensis and its associated mycorrhizal fungi

Rapid spread and growth of plants that are poisonous to animals produce large amounts of plant litter in degraded grasslands.Nitrogen(N)input may promote the growth of these poisonous plants and alter the rhizosphere microbes and arbuscular mycorrhizal fungi(AMF)in particular.However,it is unclear how poisonous plant litter affects the growth of palatable plants and their associated AMF in the rhizosphere and whether and how N deposition may mediate these effects.A greenhouse experiment was performed to test the combined effects of litter addition of a poisonous plant,Stellera chamaejasme,and N addition on the growth of a dominant grass,Leymus chinensis,AMF characteristics and soil properties.Litter addition significantly increased the ramet number and aboveground biomass of L.chinensis and soil available phosphorus(AP)concentration and decreased the spore density of AMF.However,the interaction of both treatments had no significant effects on traits of L.chinensis and AMF properties.Stellera chamaejasme liter positively affected L.chinensis by increasing AP and negatively affected AMF by combining balanced changes in soil nutrients and litter-induced allelopathic compositions.High N addition may alleviate soil N limitation and inhibit litter decomposition,thus overriding the litter's effects on L.chinensis and AMF.These findings imply that it is necessary to objectively and comprehensively evaluate the ecological functions of poisonous plants beyond their harmful effects on livestock.Simultaneously,N deposition should be an indispensable factor in predicting the relationships between poisonous plants and edible plants indegraded grasslands.