Authorization requirements to improve safety and efficacy in developmental products for biological plant protection1

In Germany, as in other countries around the world, plant protection products need to be authorized before being placed on the market. This is true not only for chemicals but also for biological products, which, in Germany, cover microorganisms (including fungi) and viruses. Therefore, an importer or manufacturer of a plant protection product must apply for authorization and submit detailed data and information to prove conformity with the authorization requirements. Beside other important subjects, it must be clearly demonstrated that a plant protection product fulfils the demands of its user as far as its intended fields of use are concerned, and that there are no adverse effects on human and animal (livestock) health, on groundwater or on other aspects of the environment. Although there is an agreement between responsible applicants, authorization holders and competent authorities that such facts should be known, it must be admitted that there are problems with details. Nevertheless, instead of being resistant to official demands for efficacy and safety of biological plant protection products, it would be better to accept them as a guide for the development of good products for the market and as a means of preventing others from being distributed, which could spoil the reputation of biological control.     

PP 1/296 (1) Principles of efficacy evaluation for low‐risk plant protection products

Specific scope

This Standard describes the principles for determining the requirements for an efficacy evaluation of low‐risk plant protection products in a registration procedure. Low‐risk plant protection products are products with low risk to human and animal health and the environment.

Specific approval and amendment

First approved in 2017‐09.     

Principles of efficacy evaluation for microbial plant protection products

Specific scope

This standard describes the principles for determining the requirements for an efficacy evaluation (effectiveness and crop safety) of plant protection products containing micro‐organisms in a registration procedure.

Specific approval and amendment

First approved in 2012–09.     

Introduction to the efficacy evaluation of plant protection products

Specific scope

This Standard describes the overall process of efficacy evaluation of plant protection products in the registration procedure.

Specific approval and amendment

First approved in 2003‐09. Revision mainly to reflect zonal assessment approved in 2012‐09.     

Implementing a globally harmonized risk assessment‐based approach for regulatory decision‐making of crop protection products

A global, harmonized evaluation system for crop protection chemicals based on exposure and risk will improve the ability to inform risk management decisions and better support innovation. This would be achieved through harmonized risk assessment‐based regulatory decision‐making realized through the application of the best available science, via integration of new methods and traditional data to create tailored exposure‐driven risk assessments. A requirement to achieve success is a structure that encourages direct communication between the regulatory community and the regulated industry, which would enable a more rapid incorporation of new technologies and advancing science. An approach that emulates the International Conference of Harmonization (ICH) for pharmaceuticals would bring together regulatory authorities and the regulated industry along with relevant experts from academia and Non‐Governmental Organizations to discuss scientific and technical advances and their implementation. These discussions would also encourage the elimination of outmoded practices that no longer serve a purpose resulting in more uniform testing requirements and best practices for data evaluation to support safe use and scientifically defensible human health and environmental risk assessments. New and developing technologies offer exciting opportunities to improve the current toxicity testing paradigms to provide better solutions and diminish animal testing. Implementation of a harmonized approach will increase the speed, efficiency and accuracy of regulatory decision‐making for human health and environmental protection while increasing the efficiency of providing safe and effective innovative products to the agriculture community. © 2020 Society of Chemical Industry     

Influence of climatic conditions and plant physiology on glufosinate-ammonium efficacy

Under field conditions the efficacy of glufosinate-ammonium on Galium aparine L. is quite often variable. Experiments under controlled conditions with G. aparine and the more susceptible species Brassica rapa L. showed that especially low relative humidity (r.h.) and low light intensity reduced the accumulation of ammonia in the plants and glufosinate-ammonium performance. As the light intensity under field conditions always exceeds the intensities applied in the experiments this parameter may not be of practical importance. In contrast, low r.h. often occurs under field conditions and could explain the variable G. aparine control. A retention study showed that retention on G. aparine was significantly higher than on B. rapa but ammonia accumulation in the plants indicated that glufosinate-ammonium uptake by G. aparine was lower than that by B. rapa . Glufosinate-ammonium performance was improved on both species by adding ammonium sulphate to the spray solution; however, the increase in efficacy by ammonium sulphate was two times higher for G. aparine than for B. rapa . Ammonia accumulation in untreated plant parts after glufosinate-ammonium application indicated some translocation of glufosinate-ammonium in B. rapa but none in G. aparine .     

Efficacy of chemical plant protection products on potato in Ukraine1

The principal potato pests controlled with plant protection products in Ukraine are Leptinotarsa decemlineata and Phytophthora infestons. Results are presented of trials of insecticides and fungicides against these pests. As a result, Sumi-alfa 5% EC (a.s. esfenvalerate), Karate water-soluble granules (a.s. lambda-cyhalothrin) and Betabytroid 2.5% EC (a.s. beta-cyfluthrin) were recommended for full-scale testing against Colorado beetle in Ukraine. Sul'fokarbation and EKhR 19517 were recommended for full-scale testing against potato blight.     

Statistical aspects of efficacy evaluation of plant protection products in field trials – a comment on EPPO Standard PP1/152

The evaluation of plant protection product efficacy in field trials is a complex task. Several aspects of the statistical evaluation are discussed in this paper, along with a recommendation to modify EPPO Standard PP1/152. Confidence intervals should be preferred over significance tests to avoid contradictions between 'statistical significance' and 'biological relevance'. Efficacy should first be demonstrated, by comparison of a new product with a well chosen reference product, using a test of non-inferiority. When non-inferiority has been established, a test of superiority can follow. Both can simply be obtained by one-sided confidence intervals of µ_Reference – µ_Product or µ_Reference / µ_Product, where µ_Reference and µ_Product are the means for the reference and the product, respectively. Confidence intervals for the ratio are easier to interpret because of the definition of percentage change. The evaluation that a trial is realistic and coherent should be performed according to the present EPPO guideline before any analysis of efficacy is made. Efficacy data from trial series should be preferred over individual trials because this represents different sites and increased sample size (number of sites and number of plots). The treatments-by-sites interaction should be modelled as a random effect in a mixed model. Software in R is available for these suggested analyses.     

Global crop production and the efficacy of crop protection - current situation and future trends

Actual and potential crop losses of eight major food and cash crops have been estimated by evaluating data from literature and field experiments. Total losses were calculated from yield reductions due to pathogens, animal pests and weeds on a regional, continental and global level. Since 1965, worldwide production of most crops has increased considerably. Simultaneously, crop losses in wheat, potatoes, barley and rice increased by 4 to 10 percent, in maize, soybean, cotton and coffee losses remained unchanged or slightly decreased. The efficacy of crop protection practices was calculated as the percentage of potential losses prevented by control. The efficacy is highest in cotton (55 percent), it reaches only 34 to 38 percent in the food crops rice, wheat and maize. The variability among cropping areas is high: In Western Europe, 61 percent of potential crop losses is prevented, in North America and Oceania 44, in all other regions 38 percent. Due to the small share of Western Europe in worldwide production of 8 percent, the efficacy of actual crop protection worldwide is only 40 percent.In view of population growth and rising food demand crop production has to be increased substantially. As potential loss rates often increase with attainable yields high productivity largely depends on effective crop protection management. Scenarios for the production of food crops by the year 2025 in developed and in developing countries are given. Recent and future developments in crop protection can contribute to establish sustainability in agriculture and to preserve natural resources. However, although effective control methods have been developed for most biotic yield constraints, the use of crop protection products is regulated by economic considerations rather than by food demand.