The work on plant protection has been done since the time of the founding of our institution, as in the two first decades of this century, and it was treated in the framework of the production fields such as viticulture, fruit growing, and vegetable growing. This stand resulted from the fact that plant conservtion as a science was in the beginning phases. With modest results and with a short activity schedule of practical work it did not manage to separate itself as an individual discipline. However, already in those times there were attempts to solve problems concerning plant culture conservation. In that manner, towards the end of the last and at the beginning of this century, many tests were done with protection materials. Performed were parallel tests of the then existing fungicides for eradicating peronospora (Plasmopara viticola) and lye(Uncinula necator).In those researches, preference was given to the BORDOSKA soup against the peronospora, and sulphur against lye. At that time also was tested the insecticide activity of tobacco extracts, were its ability to eradicate different leaf lice (Aphidina) was confirmed.
A large impulse on plant conservation came from results reached in neighbouring countries. In the beginning those experiences were applied to our conditions. That job was taken by the expert specialist that were at this time starting to make themselves eligible. Those who had a specific knowledge started to work exclusively on the plant conservation. This is how Petar Novak worked and in 1925 became the director of the newly established Entomological department , later named "Department for plant protection".
The escaped period of activity of the Institute we can divide into three main developmental phases that are determined by the development of the knowledge on plant conservation.
The period up to the coming of the protection sources on the base of DDT, which was discovered during
world war II, represents the first developmental phase. In this phase, when the protection means were very
weak, the main attention was placed on familiarization of entomofauna as a whole, and especially its
damaging agents in the Croatian Mediterranean region. In this
period the works of Petar Novak on inventarization of the beetle insect order from the mentioned region
are very significant. For his hard work Petar Novak was ordained in 1930, and towards the end of his life
he received an award for Life time achievement by the Split district city hall in 1968. Petar
Novak with his work is popular in the entomologic scientific circle across Europe and the world, and many
newfound insect types in our Mediterranean region have been given their name for our worthy scientist.
Although the possibilities of eradicating plant pests are very modest, many tests were made to limit the damaging effect of some economically significant insect types. In this manner during the fourth decade of this century was performed a testing eradication of the olive fly (Dacus oleae) in the North and South Dalmatia. In that period performed were successful eradications of the grape moth (Polychrosis botrana) and rootbiting (Capnodis tenebrionis).
For the eradication of damaging insects was used the extract got from the insect powder (Pyrethrum cinerariaefolium var. Dalmaticum). The mentioned plant was grown in the Dalmatian region, particularly in the island region. Because of the high content of pyrethrin, a source deadly to many insect types, the Dalmatian insect powder was used often for eradicating some insect pests in vegetable growing, such as the leaf lice (Aphidina), and in viticulture against different types of PIPA (Othiorhynchus spp).
In the same period successfully are performed a number of tests on plant diseases of stubble grain, agrumi and other fruit types.
In the second phase of development, after the coming DDT and a generally sudden development of phytopharmacy, the research was biological and life style of the damaging insect in the Adriatic region type of research. That was necessary for getting the most accurate application of new protection sources. Beside that carried out were numbers of biological testings of new means of plant protection. Mant of those were accepted in practice and served in eradicating pests against which the agriculturalists were powerless. Then were successfully performed wider actions in the field in the Dalmatian region. In cooperation with the experts from the Phytosanitational station in Split, actions were taken in eradicating ZICNJAKA (Elateridae). In the meantime, some sources proved themselves to be very effective against very damaging pests of olives, the moth and the fly. After testing those sources in the conditions of the Dalmatian region was determined the style of their application. In cooperation with the Phytosanitational institution organized are wide scale actions against the pests on the entire territory of Dalmatia.
In 1958 occurred a serious attack of the Mediterranean fruit fly (Ceratitis capitata), a quarantine pest in the region of Dalmatia. The experts of the Department were entrusted the testing of the behaviour of the mentioned pest and its extermination, on what many noted materials were published.
With intensifying the vegetable production and the sudden development of floriculture in Dalmatia the Activity of the Department had spread to those functions.
The increased application of different protection sources resulted in many problems across the world. The damaging consequences of greater applications manifested themselves in the dangerous polluting of the human environment, because most of the applied sources are directly or indirectly damaging to the humans health. Beside that there was an occurrence of a negative biological balance. Very significantly were weakened the economical potentials of positive biological regulators, and as a consequence followed calamitous showings of some pest types, otherwise resistant to a variety of protection sources. That is how one time harmless types became a very important problem. Stressed as an example were the consequences of an inappropriate way of eradication of olive moth and fly. Namely, with the proper timing of applying some chemical insecticides (ester phosphorus acid) it is possible to completely prevent the mentioned organisms in their damaging activity. However, the use of those insecticides was not entirely harmless. The first difficulty related to the insecticide residue that were often found in oil, in amounts that were not allowable, while the other difficulty was tied to the uncomfortable consequences of disturbed biological balance in the sprayed olive farms.
The eradication of the olive fly and moth with mentioned unselected insecticides enabled a stronger showing of shield-shaped lice (Coccina) because the useful insects (predators and parasites of shield-shaped lice) were destroyed, while the shield-shaped lice remained alive to multiply unobstructed. Therefore, a more suitable way of eradicating olive moth and fly needed to be searched for.
That new, third phase of the development of the Institute, characterizes the idea of "integrated protection", that represents the principle of individual processing in plant protection, and which are in accordance with the health demands of the environment and man.
In regards to that , for the eradication of olive fly a very important information was learned that hydrolysed proteins attract its mature forms. With their help it is possible to attract full grown flies to small surfaces. If the solution of those baits poisons the grown flies with the proper insecticide, the attracted flies will die before they drop their eggs. With that type of eradication only small amounts of baits and insecticides (hundred times less) are used, because only one branch of every third or fourth olive tree is sprayed. What that means to thew health of the humans is needless to point out. However that is not the only advantage to eradicating flies with poisoned baits. Namely, the hydrolysed proteins do not attract the predators, and this is of great importance for conserving the useful types in the olives biocoenosis. With wishes to practically present the possibilities that are available to our olive growers, the experts of the Department demonstrated, from 1975 to 1983, the mentioned type of eradication of the fly in many olive farms across the coast.
And from the stand point of eradicating the olive moth, it was necessary to consider the possibility of exchanging the usual with the selected types of eradications. Because of that were performed tests during 1978, 1979, and 1980 with Bacillus thuringiensis, a microbiological insecticide based on suspension. The results of those tests showed that it is possible to eradicate the moth without endangering the man and the biological harmony in the olive biocoenosis. This type of eradication of olive moth was accepted by many of our olive growers.
Parallel with the mentioned research and demonstrations concerning the olive fly and moth, performed are extensive researches concerning the use of useful insects (parasites) in a fight against mentioned pests. In the line of first order was the parasitic wasp (Opius concolor) that in the olive farms of Northern Africa and Southern Italy lives at the expense of the olive fly, and in the second were Chelonus eleaphilus and Trichogramma oleae, that develop destroying the olive moth. In order to establish their mass multiplying in the laboratory of the Department, it was necessary to ensure the mass production of their laboratory hosts. For the first parasite that was the Mediterranean fruit fly (ceratitis capitata), and for the second two parasites it was the flour moth (Anagasta kuhniella). That work was started in 1964 with laboratory growing of the Mediterranean fruit fly, so that it would be completed with the growing of its lab parasite , O. concolor. The lab growing of the C. eleaphilus and T. oleae was established in the lab of the Department in 1968.
The first releasing of the laboratory populations of O. concolor were done in 1968. In the next few years performed were new tests with the releasing of the Opius in the entire Adriatic region.
The release of C. eleaphilus and T. oleae, which in natural conditions are parasites of the olive moth, was done in many olive farms during 1970 and 1971.
Beside the reported, performed were researches tied to the possibility of eradicating the olive fly with sterile males. Those tests were done in a very close cooperation with the Entomologic laboratory of an International agency for the atomic energy (IAEA/FAO) located in Seibersdorf near Vienna. From June 1973 to the end of 1976 collected was 1 630 000 sterile individuals and released was 740 000 on the Kornat keys island Sit. The results of that research were published in our and foreign magazines, and reported in domestic and foreign scientific conferences (Chania on Crete, Tunisia, Jaen in Spain, Lecce in Italy).
In the frame work of the Departments activity, in 1979, was organized "Service for plant protection" which in accordance with the Law on plant protection performed the following functions:
The scientific research task of the Department is to continue working on the integrated protection of plants which includes the use of all available methods of plant protection, with an accent on biological measures and with the goal of controlling the most significant pests of our regions, conserving the environment and contributing to the production of healthy food stuff.