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Integrated Pest Management Package on Olive
Results

The Plant Protection Institute, in collaboration with the Consortium and the Albanian Organic Agriculture Association (AOAA), established three organic olive farms for the first time in 2003 in the Vlora region (with the producers of Kanina, Aliban and Shamogjin areas), totalling 5,400 olive trees. In 2003 organic olive oil was produced from 8,000 olive trees also in theTirana area. The product is certified by an international certification body, BIOSWISSE. About 3 tons of organic extra virgin olive oil are expected to be exported to Switzerland.

The evaluation of the results of the IPM method was carried out taking into account the olive fly population density throughout the activity period of the pest, the fruit infestation level and the number of bait and chemical spray applications required for achieving an acceptable crop protection level. Olive fruit fly population density was monitored using the Chromo-traps baited with sex pheromones and attractant food. Fruit damage was assessed every week and the results were compared with those where insecticide was applied and with untreated trees until harvest of crop.

At present, the monitoring of the olive fruit fly and the implementation of IPM Package in Albania is carried out by research institutions. The IPM technology for the production of organic olives is being transferred to farmers in many different ways. In cooperation with Ministry of Agriculture and Food (MoAF), regional workshops have been conducted in various areas of the main regions where olive cultivation is predominant (Sarande, Elbasan, Tirane, Berat, etc.).

Presentations on the management of olive pests have been made by the IPM CRSP project; during these events participants (inspectors, Albanian olive growers, farm advisers) were given further extension material. In cooperation with FAO, workshops and demonstrations have been organised and 10,000 Eco-traps have been distributed in order to facilitate the understanding of the IPM method and to improve the control of the olive fruit fly in Novosela district. Extension agents and farmers have been trained in the implementation of the “Attract and Kill” method. The farm demonstration trials are used to teach farmers about improved IPM technologies for olive insect pest and disease control. Through their participation in the demonstration trials, 35,000 olive trees were managed as based on IPM CRSP recommendations.

Since the innovation is based on a three-step methodology, it is important to analyze results step-by-step.

Monitoring of the olive fruit fly

Olive fruit fly (Bactrocera olea Gmelin) is the key pest damaging olives in Albania.

Trap catches (Fig 1) indicated that the olive fruit fly population varied through the year seasons. The first flies appeared during the second half of May and June. A low level of olive fruit fly population is observed during the hot and dry summer months and the mean capture /trap had never been over 20 flies/trap. At the end of August and during the autumn the olive fruit fly developed high population due to favourable conditions for fly reproduction (environmental temperatures, relative humidity and fruit susceptibility). The catches of olive fruit fly started to increase having a maximum captures on October 5 (38 flies/trap), on November 10 (44 flies/trap) and on September 5 (167 flies/trap) respectively for the years 2000, 2001 and 2002.


Fig 1. Mean capture of olive fruit fly on Chromo-trap


“Attract and Kill” method

During the course of this research, it was observed that the “Attract and Kill” method can significantly reduce olive fruit fly infestation (Fig 2.). The results obtained until the end of November, both with isolated and non-isolated olive groves, showed that one killing device per tree provided adequate protection on late ripen cultivations, especially in years when the density of the olive fruit flies’ population was limited. For that reason, curative treatments with insecticides were not necessary to keep the fly population and the fruit infestation at low level.


Fig 2. Olive fruit fly infestation during harvest time on Cv Kalinjot an isolated olive grove.


Good results have been obtained also using 1 Eco-trap every other tree in olive groves with a low or medium sized olive canopy. During the harvest period, the olive fruit fly infestation reached an acceptable level. (Fig 3)


Fig 3. Olive fruit fly infestation at the harvest period


It must be highlighted that good results have been obtained also in non-isolated olive groves where the “Attract and Kill” method was applied, using one Eco-trap per tree only in September. No significant differences have been registered when the Eco-traps have been applied twice (in June and in September) (Fig 4). In this case, it must be emphasized that the cost of the treatment is 50% lower.

Fig. 4. Olive fruit fly infestation at the harvest period


Regarding cv Frantoi (an early ripen cultivar) on the year with a low pest population density, infestation level in the orchard protected by the “Attract and Kill” technique were lower then those in untreated control and in the orchards protected by bait sprays.
However, in years with unusually damp weather, which favors the development of the olive fruit fly, both the “Attract and Kill” method and the bait sprays provided inadequate protection against infestation. In these cases, it could be necessary to apply additional insecticides or to anticipate the harvest of olives.

Olive harvest timing

The anticipated harvest of olives has proved to be a useful cultural method that contributes to the integrated control of olive fruit flies. Researches found that early harvest prevents fruits from being attacked during the olive fruit flies population peaks, while maintaining unvaried the yield and the quality of the oil. As olives mature, both the quality and the content of the oil increase (Fig.5).


Fig 5. Olive oil content of Frantoi olives (note flattening of curve from late October through November)


Depending upon the olive variety, the harvest period in Albania usually falls in late November, when the population of the olive fruit fly reaches its most dangerous level (Fig.6). One of the options that were taken into consideration was to harvest olives before the level of the olive fruit fly infestation increases. However, data were needed on the quality and the yield of the olive oil made from early-harvest olives. Over a three year period, samples of olive fruits were collected at 10 days intervals during September, October and November. The varieties used were Frantoi and Kalinjot, two important oil-producing varieties in Albania.


Fig 6. Olive fruit fly infestation in olive cultivar Frantoi (note increasing infestation level by third generation in late October and November)


The olive oils made from these fruits were analyzed at the OLITECN S.R.L. laboratory (Athens, Greece) and at the Chemiservice laboratory (Monopoli, Italy), both accredited by the International Olive Oil Council (IOOC). The olives harvested between mid October and early November were rated as extra virgin, whereas the mid November sample was rated as virgin (Tab.1). Research has provided an IPM cultural tactic that allowed an improved fruit quality due to reduced pest infestation, while maintaining acceptable oil yield and quality.




Tab. 1 Characteristics of olive oil produced on different date of harvest (year 2001)


Practical Conclusions

The anticipated harvesting of olive has demonstrated to be a useful cultural method that aid in integrated control of olive fruit fly. This method could be included in the IPM package on olive crop system. In order to have optimum of olive oil accumulation, a good olive oil quality and in the same time to avoid the high attack of olive fruit fly the best time to start the harvest for cv Kalinjoti could be considered the first decade of November and for cv Frantoi it is the first and second decade of October depending on the years. The olive oil analysis done at accredited labs by IOOC indicated that from anticipated harvesting it is possible to produce extra virgin oil.