Wednesday, July 8, 2020

Emamectin Benzoate Follow-up Post

Besides Syngenta's Aretor®/Revive®, the following are other Emamectin benzoate insecticides available to professionals: ArborMectin, Boxer, Brandt enTREE EB, Mectinite, Tree-äge, Tree-äge G4, Tree-äge R10, TreeMec

In addition, there are brandless ones but then there's the effort needed to emulsify it.



There was a study for one year of micro emulsifier insecticide Emamectin Benzoate in two formulations: Revive® 4% and ReviveII® 9.5 % against the red palm weevil (RPW) that attack date palms. It found that RPW mortality for palms applied with Revive 4% were 67.8% (month 3) and 96.6% (month 6), and as for ReviveII 9.5% mortality were 96.3% (month 3) and 100% (month 6).
At month 12, RPW mortality for both Revive 4% and ReviveII 9.5% were 100%. The RPW mortality for control palms were 3.3% (month 3), 3.3% (month 6) and 5% (month 12).

The adults fly around and deposit eggs in palm trunks. These eggs hatch within 2–5 days resulting in legless grubs that bore into the interior of the palms, feeding on the soft tissues and discarding all fibrous material. The larval stage varies from 1 to 3 months and they pupate in cylindrical cocoons made of fibrous strands. At the end of the pupation period which lasts anywhere from 14 to 21 days, adults emerge and fly out the tree searching for a new palm and potential mates.
Hence the life cycle of the RPW is between 1.5 and 4 months.
[0.3+4+2=6.3weeks or 1.5 months]
[0.7+12+3=15.7weeks or 4 months]
If there is no decrease in mortality after month 6, it could be said that the insecticide had protected the palms from infestation by RPW that were not already inside the palms, i.e., introduction of new eggs.

However the experiment seemed dodgy as Revive 4% was applied at 48 ml/palm and ReviveII 9.5% was applied at 24 ml/palm. So there is not much difference in the amount of insecticide in these two sets of samples. In addition, not all samples were the same ones used throughout the experience, as some palms were sold by the farmer during the experiment, and new palms were introduced and injected using ReviveII 9.5%.

While the author declared that this study did not receive "any specific grant from funding agencies in the public, commercial, or not-for-profit sectors", he did acknowledged two Syngenta employees for "their technical support and simplifying the fund process to conduct the experiment in the right way".

Source: Mona Mohamad Mashal, Jun 2019, The efficacy assessment of emamectin benzoate using micro injection system to control red palm weevil, Heliyon Vol. 5 Issue 6


Disadvantages of trunk injection methods include:

  • Trunk injections cause wounding and subsequent injury, or facilitate entrance of pathogens. Note that hardwoods will eventually heal over following injection, while palms will not.
  • Trunk injections can be more costly and labor-intensive.
  • Coverage with trunk injections can be spotty throughout the crown.
  • With drenching, somewhat higher amounts of chemicals must be used than with injection.
  • Trunk injection equipment can be costly.

Source: Frederick M. Fishel, Pesticide Injection and Drenching, University of Florida IFAS Extension, http://edis.ifas.ufl.edu/pdffiles/PI/PI27400.pdf, original publication date Jan 2018


Plugs for holes made in palms. Seemed like the same things that comes along with assemble-it-yourself IKEA furniture. Source: SyngentaES Facebook

Setting it in the hole. Source: SyngentaES Facebook

Hammer it in. Source: SyngentaES Facebook

Done. Source: SyngentaES Facebook

Thursday, July 2, 2020

ARETOR® by Syngenta - a Systemic Pesticide Delivered by Tree Injection

This is an unqualified review of Aretor, an pesticide for tree injection. This is not a sponsored post, and read the label and SDS before use.


The pesticide was promoted in the Middle East and Singapore as a solution against the attack of certain insect larvaes.
Red Palm Weevil (Rhynchophorus ferrugineus) in Date palms (Phoenix dactylifera), causing palm pith to be eaten and dieback of the palm.
Monkeypod moth (Polydesma boarmoides) in Rain trees (Samanea saman), causing minor tip dieback and sparse foliage in crown.
Asian long-horned beetle (Anoplophora glabripennis) in Rain trees (Samanea saman), causing bores into trunks and undermining structural stability.

Red Palm Weevil larvae and adult forms. Source: Syngenta Youtube.

Monkeypod moth larvae and adult forms. Source: AVA Annual Report 2014/2015, page 60

Asian long-horned beetle larvae and adult forms. 
Source: Wikipedia (https://en.wikipedia.org/wiki/Asian_long-horned_beetle)

Red Palm Weevil or abbrevated as RPW is distributed in the Middle East, Africa, South-west region of Europe, South Asia and South-east Asia.

The active ingredient of Aretor is 9.5% Emamectin benzoate, and is claimed to be both preventive and curative. It is a systemic pesticide and delivered into palms/trees by a low-pressure device (at 2 bars). According to the label, it seemed that the pesticide need not be applied with the official system, provided that the device "meet the label and dose requirements".

Syngenta TMI system and normal drill. Source: Syngenta Facebook

The trunk of the palm/tree would be drilled first. However, after this step, the steps of injection and plugging of holes seemed to be different depending on whether the application was done on palms or trees, according to the label and Facebook/Youtube videos. If used on palms, inject first and then cover the holes with the biodegradable plugs. If used on trees, cover the holes with the biodegradable plugs first and then inject (through the holes in the plugs?).

It is not known whether these biodegradable plugs could prevent fungus and bacteria entry into the holes.

Drilling of palm trunk. Source: Syngenta Youtube

Injection of palm trunk using the Syngenta TMI system. Source: Syngenta Facebook

For palms, a 8mm diameter drill bit was shown in the Syngenta Youtube video, and a 6mm diameter drill bit was stated in the label. The drill bit seemed to be conventional, and is at least twice as large as compared to a resistograph drill bit (3mm diameter head). The hole made by a conventional drill bit does not "close back" when retracted, unlike the resistograph drill bit.

Use 8mm diameter drill on palms. Source: Syngenta Youtube

For trees, a 10mm diameter drill bit was used as stated in the label. Application rate depends on the tree's diameter at breast height (DBH). According to the label, holes are to be drilled slightly slanting, close to the ground into the active sapwood of root flare.

He seemed to be inserting plugs into drilled holes. Note the plug at the lower left of this photo. Source: Syngenta Facebook

Injection of Rain tree using the Syngenta TMI system. Note that the root flare is not apparent in this specimen. Source: Syngenta Facebook

In one of Syngenta's Facebook post, it was mentioned palms could be protected against weevils for "up to one year at $50* per palm... *Terms and Conditions Apply".
According to the label, the persistence of Aretor in palms is 6-12 months, so the application could be once or twice a year. The application rate for palms is 21-42ml per palm, hence the 1 litre bottle could be used for the following number of treatments:

  • 21ml - 47 applications
  • 42ml - 23 applications

But before the application of pesticides as a preventive measure, shouldn't a proper fertilisation regime and cultural practices (i.e., not injuring the palm trunks, etc.) come first?