Norbert Billenkamp. NiCoTa GmbH

Transcription

1 Norbert Billenkamp NiCoTa GmbH

2 Questions: 1. Is the behaviour of different pesticides regarding the distribution in whole leaves, separated lamina and separated midribs the same or not? 2. Which pesticides contaminate completely untreated tobacco? 3. What is the influence of the location and irrigation on pesticide behaviour?

3 Methods 1. Two locations: a) Forchheim sandy loam and irrigated b) Ettlingen loam and none irrigated 2. At both locations a completely untreated block was grown 3. Pesticides were applied with a regular field sprayer 4. Sampling was done for all six reapings a) Untreated tobacco directly after curing b) Production control at the grading - two or three leaves from each plot of a trial with altogether 39 plots

4 Pesticides under investigation Active Material Trade name a.i. / ha (g/ha) Dimethomorph Forum 225 & 225 Date of application(s) & Reapings (date) Forchheim PHI (days) Forchheim Reapings (date) Ettlingen PHI (days) Ettlingen 18 & 7 25 & 14 Maneb Vondac DG Cyazofamid Ranman Fluopyram Luna Sensation Trifloxystrobin Luna Sensation Maleic hydrazide ITCAN SL Mandipropamid Difenoconazole Revus TOP Revus TOP 150 & & & & & 13

5 Structure of the following slides vs Untreated tobacco Treatment GRL GRL

6 Results Dimethomorph Residues vs Untreated tobacco

7 Results Dithiocarbamate Residues vs Untreated tobacco

8 Results Cyazofamid Residues vs Untreated tobacco

9 Results Fluopyram Residues vs Untreated tobacco

10 Results Trifloxystrobin Residues vs Untreated tobacco

11 Results Maleic Hydrazide Residues vs Untreated tobacco

12 Results Mandipropamid & Difenoconazole Residues Residue Trial Untreated Tobacco Mandipropamid: Difenoconazole:

13 Summary 1. The eight examined pesticides differ regarding the absolute levels of pesticide residues. 2. The climatic conditions in a year have a great impact on pesticide residues in and on tobacco. ~ 2015 was a hot an dry summer (34,7 mm rainfall in July, wherat 18,3 mm were on one day). Irrigation in Forchheim from beginning of July on a nearly weekly basis reduced pesticide residues compared to none irrigated tobacco (Ettlingen) to a meaningful extend. ~ 2016 the rainfall in July (47,2 mm) was much more even distibuted and two times irrigation from the end of July had no effect on pesticide residues.

14 Summary 3. Residues in the first stalk position are much higher than in the subsequent ones 4. Residues in midribs are negligible compared to lamina and whole leaves 5. Some a.i. tend to have higher residues in lamina compared to whole leaves (Dimethomorph, Trifloxystrobin) 6. The risk of the contamination of not treated tobacco is given especially for Fluopyram and Trifloxystrobin

15 My answer to the question above : Sometimes pesticide residues in and on tobacco are a huge mystery!!!! Thank your for your attention!