LOW KNOCKDOWN - HIGH SHUTDOWN Neem contains several active ingredients, of which the most important is Azadirachtin. It has been estimated that Azadirachtin accounts for up to 90% of the bioactivity of neem, but there is so much synergism at work in this pesticidal cocktail of four major and twenty minor active components, that it is impossible to quantify a percentage. Neem compounds bear no resemblance to synthetic pesticides. They are composed only of carbon, oxygen and hydrogen and contain none of the chlorine, phosphorus, sulfur or nitrogen atoms found in synthetic chemicals. Chemically neem resembles steroid compounds like cortisone and oral contraceptives, and there is a very different mode of action compared to the conventional “Wham, bam, thank you Maam!” of the toxic knockdowns. In most cases neem extracts are not knockdown killers. Instead they create hormonal disruption, which prevents the insect from feeding, breeding or metamorphosing. It is a far more subtle process, which eventually prevents the insect from causing further damage. It is a hormonal shutdown rather than an instant knockdown. HORMONAL LOOK-ALIKES ALLOW EASY ACCESS The active compounds in neem belong to a general class of natural products called ‘Triterpenes’, or more specifically, ‘limonoids’. There are at least ten limonoids in neem, but the most researched of these are Azadirachtin, Salannin, Meliantriol and Nimbin. Azadirachtin is the most significant of these. Thirty years of research suggest that Azadirachtin is one of the most potent growth regulators and feeding deterrents ever tested. It is in fact so potent that quantities as low as 1 ppm (part per million) will totally repel some insects. Meliantriol and Salannin are powerful feeding inhibitors, while Nimbin has been found to have antiviral activity. Neem compounds have a very similar shape and structure to several critical insect hormones. This look-alike feature tricks the insects’ bodies into absorbing the neem compounds as if they were the vital hormones. The neem infiltrators shut down the endocrine systems, and the hormonal chaos that follows sees populations plummet.