C ONTRIBUTION TO A BETTER UNDERSTANDING OF FLIGHT PATTERN AND EGG - LAYING DURATION OF THE P ISTACHIO SEED WASP Mohamed BRAHAM University of Sousse. Laboratory of Entomology and Insect Ecology. Regional Research Center of Horticulture and Organic Agriculture Chott-Mariem. Sousse. Tunisia. BRAHAM. GREMPA. MEKNES12-15MAY2015

PLAN INTRODUCTION PROBLEMATICS OBJECTIVES OF THE STUDY MATERIELS AND METHODS RESULTS CONCLUSIONS AND RECOMMENDATIONS BRAHAM. GREMPA. MEKNES12- 15MAY2015

THE PISTACHIO TREE, PISTACIA VERA ► Pistachio is a tree of great interest for reforestation and exploitation of poor lands. ► It is well adapted to various climatic conditions and supports long periods of drought ► It occupies larges lands which are less appropriate or even inappropriate for other crops such as almond or olive trees BRAHAM. GREMPA MEETING. MEKNES12-15MAY2015

THE PISTACHIO CULTIVATION IN TUNISIA  Total cultivation area 4400 ha in 1980 to ha in 2002 (Onagri, 2015).  The yield is very low averaging 28 kg per ha in 2002) BRAHAM. GREMPA. MEKNES12-15MAY2015

PROBLEMS CONCERNING PISTACHIO CULTIVATION IN TUNISIA  Dioecious tree : pollination required  the lack of synchronization of flowering periods for male and female trees  pruning, irrigation, nutrition  the attack of insects and pathogens BRAHAM. GREMPA. MEKNES12-15MAY2015

KEY INSECTS ATTACKING PISTACHIO IN TUNISIA ► The Pistachio seed wasp: Eurytoma plotnikovi ► The pistachio seed chalcid: Megastigmus pistaciae ► The Scolytid : Chaetoptelius vestitus BRAHAM. GREMPA. MEKNES12-15MAY2015

SPRING WINTER SUMMER Autumn -Winter Oviposition Larval development Diapausing larvae BRIEF BIOLOGY THE PISTACHIO SEED WASP E URYTOMA PLOTNIKOVI BRAHAM. GREMPA. MEKNES12-15MAY2015

PROBLEMATICS E. plotnikovi destroys up to 70 % of nuts in some orchards without control The control of this pest is undertaken with a wide range of insecticides. Discrepancies on the optimal time to treat coupled with the difficulty of the monitoring the adult population has resulted in several sprays generally applied at unsuitable periods (usually in late May -June each year) and then are ineffective. BRAHAM. GREMPA. MEKNES12-15MAY2015

OBJECTIVES OF THE STUDY The contribution to the knowledge of the biology of Pistachio seed wasp To determine the period of oviposition activity of females in order to establish better control methods (Using contact insecticides to control adults or systemic insecticides to control larvae Pistachio nuts Left attacked Right Healthy BRAHAM. GREMPA. MEKNES12-15MAY2015

MATERIALS AND METHODS 1. Monitoring the infestation and adult emergence From late April to early July in 2005, 2006 and 2011 Collection of 50 old nuts and 50 freshly formed nuts from at least 5 trees BRAHAM. GREMPA. MEKNES12-15MAY2015

Old nuts were split to record Number of filled nuts Number of unpollinated nuts Number of mature larvae, pupae, adults Number of nuts with exit holes (emerged adults ) BRAHAM. GREMPA. MEKNES12- 15MAY2015

Newly formed nuts were dissected in the laboratory and infestation was sorted on eggs, young larvae, developing larvae, old larvae BRAHAM. GREMPA. MEKNES12-15MAY2015

2. Caged, un-caged pistachio nuts tests 24 Pistachio twigs bearing from 10 to more than 100 nuts were caged on April 30, marked twig, exposed continuously to natural infestation was used as a control. 1 twig caged on April 30 was left continuously caged till the end of the experiment (July 30). Cages were sequentially removed (each one every 3 -5 days) and re- caged after 3 to 5 days. This period was devoted to allow wild females oviposition in the orchard BRAHAM. GREMPA. MEKNES12-15MAY2015

RESULTS 1. Monitoring the infestation in the orchard (YEAR 2005) Percentage of larvae, pupae, adults and empty nuts obtained by picking and splitting 50 nuts. BRAHAM. GREMPA. MEKNES12-15MAY2015

Y EAR 2006 Percentage of larvae, pupae, adults and empty nuts obtained by picking and splitting 50 nuts. BRAHAM. GREMPA. MEKNES12-15MAY2015

Y EAR 2011 Percentage of larvae, pupae, adults and empty nuts obtained by picking and splitting 50 nuts. BRAHAM. GREMPA. MEKNES12-15MAY2015

In 2005, the oviposition commenced on May 4 to take end on June 4, 2005 although, eggs were detected in nuts on July, 9 but in very small numbers.The maximum of eggs were deposited at around 10 May 2005 Dates Eggs on the inner part of the endocarp Eggs on embryo Total 27/04/ /04/ /05/20053 (100%)0 3 07/05/20057 (87.5%)1 (12.5%)8 10/05/ (95.83%)1 (4.16)24 14/05/ (66.66%)1 (33.33)3 17/05/ (100%)0 (0%)7 20/05/20057 (87.5%)1 (12.5%)8 24/05/20055 (83.33%)1 (16.66%)6 27/05/20057 (100%)0 (0%)7 01/06/20054 (100%)0 (0%)4 04/06/20052 (100%)0 (0%) 2 09/06/ /06/ /06/ /06/ /07/ /07/ /07/20052 (100%)0 (0%)2 12/07/ Egg laying period characterization in the orchard BRAHAM. GREMPA. MEKNES12-15MAY2015

Dates Eggs on the inner part of the endocarp Eggs on embryoTotal 23 -April April April April May-0612 (70.60%)5(29.4%) 17 7-May-065 (45.45%)6 (54.55%) May-0612 (75%)4 (25%) May-067 (53,85%)6 (46.15) May-064 (80%)1(20%) 5 20-May-065 (100%)0 (0%) 5 24-May-064 (100%)0 (0%) 4 27-May-065 (71.40%)2 (28.60%) 7 1- June June June June In 2006, the egg laying period commenced on May 4 to finish at the end of the moth (27 May) with a maximum from 4 May to 14 May 2006 BRAHAM. GREMPA. MEKNES12-15MAY2015

Dates Eggs on the inner part of the endocarp Eggs on embryo Total 30/04/ /05/ (68.42%)6(31.58)19 10/05/20115 (71.42%)2(28.58)7 12/05/20114 (80%)1 (20%)5 16/05/ (58.82)7 (41.18)17 19/05/ (100 %)0 (0%)2 23/05/ (100 %)0 (0%)6 26/05/20112 (100 %)0 (0%)2 31/05/ (100 %)0 (0%)2 06/06/ /06/ /06/ /06/ /06/ /06/ In 2011, the egg laying period was concentrated in May with a maximum occurring on 16 May, 2006 BRAHAM. GREMPA. MEKNES12-15MAY2015

3. Caged, un-caged tests Table. Dates of caged, un-caged and re-caged twigs as well as the presence/absence of mature larvae of E. plotnikovi at harvest (22 August, 2005) RESULTS BRAHAM. GREMPA. MEKNES12-15MAY2015

0 = Absence of mature larvae of E. plotnikovi at harvest (August, 22, 2005) 1 = Presence of mature larvae of E. plotnikovi at harvest (August, 22, 2005) * Continuously covered and opened on July 30, 2005 ** Continuously exposed to natural infestation and served as a control CagedUn-cagedRe-caged Presence/absence of E. plotnikovi larvae at harvest 30/4/054/5/057/5/050 30/4/057/5/0510/5/051 30/4/057/5/0510/5/050 30/4/057/5/0510/5/050 30/4/0510/5/0514/5/051 30/4/0510/5/0514/5/050 30/4/0510/5/0514/5/050 30/4/0510/5/0514/5/050 30/4/0514/5/0517/5/051 30/4/0514/5/0517/5/050 30/4/0517/5/0520/5/050 30/4/0517/5/0520/5/050 30/4/0520/5/0524/5/050 30/4/0520/5/0524/5/050 30/4/0524/5/0527/5/051 30/4/0527/5/0501/6/051 30/4/0527/5/0501/6/050 30/4/0501/6/0504/6/051 30/4/0501/6/0504/6/050 30/4/0504/6/0509/6/051 30/4/0504/6/0509/6/050 30/4/0509/6/0514/6/050 30/4/05*0 30/4/05**1 YEAR 2005 BRAHAM. GREMPA. MEKNES12-15MAY2015

CagedUn-cagedRe-caged Presence/absence of E. plotnikovi larvae at harvest April, 26,May, 3, 2006May, April, 26May, 3May, 60 April, 26May, 6May, 81 April, 26May, 6May, 80 April, 26May, 8May, 110 April, 26May, 8May, 110 April, 26May, 11May, 130 April, 26May, 11May, 130 April, 26May, 13May, 160 April, 26May, 13May, 160 April, 26May, 16May, 180 April, 26May, 16May, 180 April, 26May, 18May, 200 April, 26May, 18May, 200 April, 26May, 20May, 230 April, 26May, 20May, 231 April, 26May, 23May, 261 April, 26May, 23May, 261 April, 26May, 26May, 290 April, 26May, 26May, 291 April, 26May, 29June, 10 April, 26May, 29June, 10 April, 26June, 1June, 30 April, 26June, 1June, 30 April, 26June, 3June, 60 April, 26June, 6June, 90 April, 26June, 6June, 90 April, 26June, 6June, 90 April, 26June, 9June, 130 April, 26June, 9June, 130 YEAR 2006 BRAHAM. GREMPA. MEKNES12-15MAY2015

C ONCLUSION AND RECOMMENDATIONS Adult flight : begins in late April, early- May and lasted to late May, early-June The oviposition starts at the beginning of May to last till the end of the month To be effective, sprays have to be taken during all the period of adult flight - Encourage farmers to remove all nuts on and beneath the pistachio trees and destroy them before the end of the winter - The use of cage harboring old nuts in the orchard and monitor adult emergence BRAHAM. GREMPA. MEKNES12-15MAY2015

Many thanks are due to -Mediterranean Institute Agronomic of Zaragoza (IAMZ) -- Ecole Nationale d’Agriculture de Meknès -Professor Jean-Yves RASPLUS (INRA Montpellier, France) for the confirmation of the identification of E. plotnikovi. -the former and current director of “the Higher Institute of Agricultural Sciences of Chott-Mariem” for permitting to use the Pistachio orchard. BRAHAM. GREMPA. MEKNES12-15MAY2015