Please check this useful researchgate link and PDF attachments.

https://www.researchgate.net/publication/290061838_A_review_on_efficacy_of_biopesticides_to_control_the_agricultural_insect's_pest

Article A review on efficacy of biopesticides to control the agricul...

Sir..These all botanical pesticide effectiveness depends on percentage of active content. For example for Neem oil, Azadirectin is responsible for action But lower percentage of azadurectin might not produce good results. Azadirectin higher then 10000 PPM have effective action. Dose is also important. And last all these variery is natural, so seasonal vatiation also change the effectiveness of product.

Dear Aloke,

The efficacy of the botanical insecticides depends on many factors such as the the concentration of the active material, the higher the concentration the more the efficacy, the organic solvent, the presence of surfactant, the period after extraction, the longer the period,  the efficacy will drop, the way of storing the extract, if not properly stored for example ( in the freezer) also this will affect the efficacy. The method of preparing the stock solutions , etc..

Thank you so much sir,,,

Dear sir, in the d formulation I used water as a diluents / solvent, edible surfactant/emulsifier. 4000 ppm active ingredient was used for mortality test. I did't get any noticeable efficacy. Please suggest me the superior ingredient for the above formulation so that I get desired efficacy.

Look at  the expiry date, and are you using extract or a commercial green insecticide?

Sir I have developed few  formulations using some medicinal plants. I used current formulation and the active ingredient  @4000 PPM  for efficacy trial, but I don't get desired efficacy. Can we expect > 90% mortality form botanical pesticides?

dear Aloke , are you use plant extract or a commercial green insecticide?

Dear Ammar Jasman,

I using plant extract for the bioefficacy analysis..