Bayer: Delving into the Development of VLV Formulations and Application by UAV

AgroPages recently interviewed Dr. Malcolm Faers, formulation scientist and Senior Science Fellow, Crop Science Division of Bayer. In this interview, he shared his views on the key considerations for designing formulations for UAV (unmanned aerial vehicle) application, Bayer's VLV/UAV formulations and application situations worldwide, as well as the opportunities and challenges for the UAV aerial application market and more.

Dr. Malcolm Faers

Formulation Scientist and Senior Science Fellow, Crop Science Division of Bayer

What are the challenges and solutions for the development of agrochemical formulation for aerial application? Key considerations for designing UAV aerial application formulations. 

A key challenge is achieving the required coverage at the very-low spray volumes (VLV) used with UAV, which has been demonstrated to reduce efficacy (Wang et al, Pest Manag Sci 75:1546-1555 (2019)). For UAV application it is important to design formulations that maximise delivery of the active ingredient(s) to the target and minimise off-target losses, and what is notable here is that the different concentrations of the formulation (and its formulants) encountered in the spray dilution at VLV offer interesting opportunities to achieve this in the formulation design compared to higher spray volume application. Solutions include formulations with enhanced spray retention, enhanced uptake and enhanced spreading.

Could you share some representative UAV aerial application/ VLV formulations and special features? Share some successful cases to develop them based on different scenarios and market needs. 

Bayer has a wide range of products suitable for UAV application, and further advanced products are in development. Key formulation design features include enhanced spreading and uptake at VLV, with the formulation design often quite different for those designed for higher spray volumes. The formulation design can also vary for different leaf properties, with higher foliar spray retention properties important for difficult to wet leaves for example. In APAC products are already available/registered for use in CHN, JPN, KOR, IND, MYS, PHL amongst others, with over 20 products so far registered in Japan for UAV application. Product examples include Nativo, Vayego, Movento and Confidor (country dependent).

How does your company maximize biological efficacy by adjuvant and nozzle technology for UAV aerial application?

We are testing our existing products for UAV application, including spray solution stability at VLV, biological efficacy and crop safety. Additionally, we are also designing new products for UAV application with enhanced retention, uptake and/or spreading while maintaining good crop safety. Testing includes VLV lab-based greenhouse trials and UAV fields trials. Furthermore, formulations are designed for a wide range of nozzle technologies, including hydraulic nozzles and spinning discs, tolerance to a wide range of spray droplet sizes for reduced drift application, and for application over a wide range of spray volumes.

Could you talk about the situation of UAV aerial application of your company worldwide? What are the factors affecting its rapid development? 

Aerial application by UAV is a growing application practice with the potential to disrupt a range of current application practices. After the introduction of the petrol-powered Yamaha R-50 in Japan (1991), battery powered UAVs (ca. 2015+) have rapidly expanded aerial spray application in APAC, especially in China and very recently in India. Key uptake factors include relatively low UAV costs, easily obtained UAV licences, replacement of limited manual labour for rice paddy treatment, reduced operator exposure and minimal registration barriers for UAV application. UAV spray application is also growing in other parts of the world including LATAM, NA, Australia/NZ and some parts of Africa, turning it into a truly global application technology.

How do you view the development of China's UAV aerial application? What solutions does your company have?

It is a leading example and successful model for UAV introduction with a rapidly growing market for UAV application. Bayer has a range of customer focused products available here, including rice, cereal, fruit and new corn solutions previously unavailable by conventional application techniques (manual ground spray).

What and where are the biggest opportunities and challenges for the UAV aerial application market? 

UAV spray application offers interesting opportunities for improved sustainability compared to tractor-based spraying through reduced water volumes, reduced soil compaction and targeted/spot spraying. Big opportunities exist in the smallholder market replacing knapsack sprayers and reducing operator exposure. Challenges remain with uniformity of application, missing regulatory approvals in certain parts of the world and drift risk of herbicide spray application, which in the case of paddy rice herbicides can be overcome with UAV drip application for example.

This article was published in AgroPages '2023 Formulation & Adjuvant Technology ' magazine published this May.

If you'd like to share your company's story and products/solutions. Please contact Grace Yuan via: grace@agropages.com