CRISTINA CARLOS1,2, FÁTIMA GONÇALVES2, MARIA DO CARMO VAL1, SUSANA SOUSA2,
MÁRCIO NOBREGA3, JOSÉ MANSO1, RUI SOARES4, ÁLVARO MARTINHO4, SÉRGIO SOARES4, LAURA TORRES2
1 ADVID – Association for the Development of Viticulture in the Douro Region, Quinta de Santa Maria, Apt. 137, 5050-106 Godim, Portugal cristina.carlos@advid.pt
2 Centre for the Research and Technology of Agro-Environmental and Biological Sciences, CITAB, University of Trás-os-Montes and Alto Douro, UTAD, Quinta de Prados, 5000-801 Vila Real, Portugal
3 SOGEVINUS FINE WINES S.A., 4400-111 Vila Nova de Gaia, Portugal
4 REAL COMPANHIA VELHA- R. Azevedo Magalhães, n.º 314 Oliveira do Douro, 4430-022 Vila Nova de Gaia
MATING DISRUPTION AGAINST Lobesia botrana (DEN. & SCHIFF) USING ISONET-LTT DISPENSERS IN THE DOURO WINE REGION (PORTUGAL)
INTRODUCTION METHODOLOGY
RESULTS
ISONET-LTT dispensers were installed in two wine farms, S. Luíz, under MD since 2009, and Carvalhas (Figure 1), where this technique was applied for the first time in 2011. In the period of 2011-2013, the dispensers used were loaded with 300 mg of pheromone, (recommended dose was 400 dispensers/ha), while in 2014 the dispensers were loaded with 400 mg of pheromone (recommended dose was 300 dispensers/ha). In both cases, it was intended to apply 120 g of pheromone per ha. However the number of dispensers applied was always higher than the recommended (Table 1).
The European grapevine moth, Lobesia botrana, is the most important pest in the Douro Wine Region (DWR), where it typically develops three generations per year, being the third one, the most damaging to grapes.
CONCLUSIONS
Table 1 – General information about the use of ISONET-LTT dispensers for MD of Lobesia botrana
Capture reduction
Mating disruption against L. botrana have been registered in Portugal since 2000, with ISONET-L (Shin-Etsu Chemical Co. Ltd., Tokyo), loaded with 172 mg of E,Z-7,9- dodecadienyl acetate. The use of this dispenser over the years (2000-2010) in DWR allowed the identification of some major constraints. In order to overcome these constrains, since 2011, under ECOVITIS project, a new dispenser (ISONET-LTT), has been tested in 180 hectares of DWR vineyards.
The goal of this study was to evaluate the effectiveness of this dispenser in the control of L. botrana in two wine farms, Quinta de S. Luíz (Sogevinus Fine Wines SA) and Quinta das Carvalhas (Real Companhia Velha), as well as the effect of varying dispenser point source density, changing the concentration of pheromone per dispenser and keeping the amount of pheromone applied per hectare constant.
Poznan, Poland January 14-16, 2015
Year 2011 2012 2013 2014
Amount of pheromone / dispensers (mg) 300 300 300 400
S. Luíz
Surface (ha) 90,0 90,0 90,0 90,0
Nb dispensers 442 478 460 341
Date application 7-9 Jul 26 Mar 27 Mar 13 Mar
Carvalhas
Surface (ha) 14,1 37,0 45,6 45,6
Nb dispensers 442 478 495 388
Date application 28 Mar 26 Mar 18 Mar 23 Mar
Evolution of pheromone in the dispensers
The active ingredient in the dispensers of S. Luíz was calculated over time, by weighing (0.0001g accuracy) samples of 10 dispensers at two altitudes (80, 400 m). In 2013 they were installed later on 19th April and collected monthly until November; in 2014 dispensers were installed on 13th March and collected monthly until October.
Evaluation of MD efficacy
MD efficacy was evaluated by comparing trap catches, between treated and untreated plots. Traps were checked weekly and percentage of reduction of catches was calculated. The infestation was assessed by inspecting samples of 50-100 inflorescences or grapes during each generation (results not presented) and at harvest, to look for damages. Each time the economic threshold level (ETL) was surpassed (5% infested clusters), a treatment was applied with IGR, mainly in the 2nd and/or 3rd generations.
Year 2011 2012 2013 2014
Amount of pheromone / dispensers (mg) 300 300 300 400
S. Luíz
Total trap captures (Control) 951 1069 887 693
% reduction on captures (MD) 95.5-99.6 98.5-100.0 99.2-100.0 99.7-100.0
Carvalhas
Total trap captures (Control) 989 436 910 858
% reduction on captures (MD) 97.9-98.9 96.3-100.0 99.2-100.0 89.4-100.0 Table 2 – Captures of Lobesia botrana on control and % of reduction (range of variation) on MD plots
Infestation
In comparison with the control plot, the captures in the traps located in the MD plots were reduced by 89-100% (Table 2), suggesting that MD almost prevented completely the males from locating the traps.
Figure 1– Carvalhas (left) and S. Luíz (right) winefarms (Source: ESRI Arcgis online). The colored polygons represent area under MD
In general, L. botrana infestation in MD plots was lower than on control plots (Figure 3).
However sometimes, such as in S. Luiz, in 2011, complementary insecticides had to be applied. In this case the high levels of infestation found were probably due to the late application of the MD dispensers. In 2013, in spite of the higher level of L. botrana infestation found on the control plots, the infestation on MD plots was reduced to a level where the technique could be used alone, in most of the plots. In 2014, MD didn´t performed so nicely as in 2013, and insecticides had to be applied in a number of plots.
Several reasons may have contributed to the poorer results obtained, namely: a) the higher pressure of L. botrana - particularly in the 3rd generation, favored by the sweet summer (lower temperatures on July and August), and b) the use of dispensers and dose of application less effective.
This research was developped under Ecovitis project, funded by Programa de Desenvolvimento Rural – Ministério da Agricultura, Mar, Ambiente e Ordenamento do Território – Fundo Europeu Agrícola de Desenvolvimento Rural – A Europa investe nas zonas rurais.
We also would like to thanks to the technical staff of the farms , for their collaboration and support on this study.
De Lame FM, Epstein D, Gut LJ, Goldfarb H, Miller JR. 2010. Effect of varying dispenser point source density on mating disruption of Grapholita molesta (Lepidoptera:
Tortricidae). J Econ Entomol 103(4): 1299-305.
Results indicate that MD can be effective to control
L. botranain the hard conditions of DWR. ISONET-LTT dispensers helps to overcome the problem of early pheromone exhaustion, which was one of the main constraints to the use of the technique in this region. So, in the beginning of the 3
rdgeneration the dispensers still had 30-40% of active ingredient (Figure 2). However, data suggest that, under DWR conditions, the use of 300 mg dispenser, with more point sources per hectare is more effective to control the pest, than the use of 400 mg dispenser. By the way, the decreasing of point source density, even keeping constant the amount of pheromone used per hectare, is not a viable option for reducing the cost of MD, as shown by De Lame et al. (2010).
REFERENCE
Evolution of pheromones in the dispensers
The highest loss of pheromone in dispensers happened between July and September, coinciding with the period of higher temperatures. However, at the beginning of the 3rd flight of L. botrana (August 6th in 2013 and August 18th in 2014), the remaining active ingredient on dispensers was 30-40% (note that in 2013, the dispensers weighed were installed 23 days after the deployment on field and so, the % of active ingredient in this dispensers was lower that the value shown in Figure 2A). Apparently, the release rate of pheromone was higher in the lower altitudes.
Figure 3 – Clusters damaged by Lobesia botrana at harvest (%) (average of attack of several plots with similar location on the hill). * - Sprayed with insecticide in some plots, against 2nd or 3rd generation. In red, the economic threshold level (5%).
0 10 20 30 40 50 60
2011 2012 2013 2014
Clusters damaged (%)
S. Luíz
Control Upper Middle Down
300 mg 400 mg
*
*
*
*
*
* *
*
* * *
2011 2012 2013 2014
Carvalhas
Control Upper middle Down
300 mg 400 mg
* *
*
* * * *
Lower Lower
ETL
Middle
Figure 2– Evolution of the % of active ingredient on dispensers at two altitudes (80, 400 m) and
monthly average temperatures in 2013 (A) and 2014 (B). Arrows indicate the beginning of the 3rd flight
A B
