Tank mix additives

Insecticides and fungicides are usually applied postemergent, when the insect or disease is present. The application characteristics and tank mix additives used for herbicides are very similar to those for insecticides and fungicides. As often as possible, pesticides and fertilizers are applied simultaneously to avoid multiple trips through the fields. 

This leaves two basic formulation types to consider. The first is the capsulated suspension (CS) formulation. This formulation is used to deliver a version of the active ingredient that has a reduced toxicity, reduced volatility, or a reduced release rate. The agrochemicals application area is one of the key areas when encapsulation technology has yielded commercial products. The second category is tank mix additive (TMA). The TMA is not really a formulation type on its own, but is rather any material diat is added to a tank mix to aid or modify the action of the agrichemical, or die physical characteristics of the mixture(l). It can be in almost any form, and can function in one or more of a multitude of mechanisms. 

This spring Elanco Products Company (a Division of Eli Lilly and Company) introduced a 60 /o dry flowable (or water dispersible granule) formulation of BALAN. BALAN is a preemergence, dinitroaniline herbicide used on peanuts and lettuce. BALAN Dry Flowable is an addition to formulations of BALAN which are produced and sold by Elanco. BALAN LC, a 1.5 Ib/gal emulsifiable concentrate which has been on the market for several years, is often tank mixed with several other agrichemicals. Therefore, it was critical to evaluate this new product form for tank mix performance with all agrichemicals with which it could be tank mixed. 

Pyrethroids are formulated as emulsifiable concentrates, wettable powders, granules, and concentrates for ultralow volume application. They may be combined with additional pesticides (sometimes highly toxic) in the technical product or tank mixed with other pesticides at the time of application. AAS-TAR is a combination of flucythrinate and phorate. Phorate is a highly toxic organophosphate. 

The benefits of an anchor mixer are limited by the fact that the vertical blades provide very little fluid motion between the top and bottom of the tank. Ingredient additions at the surface of the fluid may make many rotations before gradually being spread and circulated to the bottom of the tank. To promote top-to-bottom fluid motion, angled blades on the anchor or helical ribbon blades, described in the next subsection, make better mixers for uniform blending. Significant viscosity differences between fluids may extend mixing times to unacceptable limits with the basic anchor. 

Flexibility of Use. Products based on Bt have been successfully incorporated into pest management programs in agriculture, forestry and vector control. This is largely due to the fact that the Bt delta endotoxin and spores are relatively stable when tank mixed with conventionally used fungicides, insecticides and spray adjuvants. In addition, most commercial Bt formulations have been designed to optimize shelf life, as well as physical compatibility with other agricultural chemicals and application systems. 

The increased weed control in carbamothioate + atrazine or metolachlor tank mixtures may be due to the 1) additive/synergistic action of the tank mix 2) inhibition of enhanced biodegradation, or 3) activity of atrazine as a mild extender for carbamothioate herbicides. 

Potentially, a safener could increase the tolerance of the crop by reduction of herbicide uptake and translocation, or by enhancement of metabolic herbicide inactivation in the crop tissue. Furthermore, a safener could counteract the effect of a herbicide at its biochemical target site, with a resultant reduction of crop susceptibility. Evidence for and against these potential modes of action is presented in the following sub-sections. In addition, aspects of safener specificity (crop versus weed) are covered for situations where the safener is applied in tank mix with the herbicide. 

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