The Institute of Agriculture-Kyustendil is a structural link of the Agricultural Academy of the Ministry of Agriculture and Food and is a specialized departmental research institution for investigation of theoretical and practical problems in agriculture, introduction of Bulgarian and foreign achievements in this area, assistance to the growers for the development and prosperity of this branch. It is an assignee of the founded with Ordinance №2646/19.12.1929 of the Ministry of Agriculture and state properties, Fruit-growing Experimental Station, Kyustendil.
    After its foundation this scientific institution became not only the first practical, but also the first scientific fruit-growing center in our country. Here, down the ages prominent scientists worked at the domain of fruit-growing.
    Nowadays the researchers and specialists from the Institute of Agriculture aim to face all challenges set in front of the agricultural science and practice.

    The Fruit-growing Experimental Station, Kyustendil began its activity by – the director Assoc. Prof. Todor Zahov. He investigated the inter-sterility of sweet cherry cultivars and determined 3 inter-sterile groups; the degree of fertility of plum and sour cherry cultivars, the influence of the climatic factors on the quantity of cherry production in the region of Kyustendil. He carried out experiments on chemical control of pests and diseases of plum and apple trees. For the first time in Bulgaria he performed cytological studies on fruit trees.
    In 1939 as a Director of the Station was appointed Res. Assoc.  Petar Lilov. He initiated an agrotechnical experiment and started studies on the fruit tree assortment in the region. After his resignation, due to the unfavourable work conditions, for a short period the Station was directed by the district agronomist at the Agricultural Department, Stoyan Vassilev .
    In 1940, as a director was appointed Prof. Tsocho Spasov  As a result from his efforts and persistence, two more decrees for land settlement of the station were signed by the King of Bulgaria – Boris the 3rd . As a result, 283 da from the territory of the village of  Nikolichevci, close to Kyustendil, became a property of the Station and were paid in full to their proprietors. He began investigations on the sweet cherry cultivars Edra belvica, Peresta belvica and Obiknovena belvica, initiated agrotechnical experiments with apple and pear trees.
    At the end of 1944 the Experimental and Control Station grew into Fruit-growing Research Institute, subdivided into 3 departments: breeding and cultivar studies, agrotechnology and plant protection. Experiments on irrigation, clonerootstocks and plant protection were initiated.
    In 1947 as a Director of the Institute was appointed Prof. Ivan Iliev. The already initiated studies concerning the biology and the plant protection methods for control of the economically important diseases – peach leafcurl redleaf spot (Taphrina pruni) and pests - cherry fruit fly, codling moth, apple blossom weevil were continued and extended. Began work on the creation of plum cultivars resistant to red leaf spot and sharka, apricot cultivars with a long dormant period; apple, pear and peach cultivars with better gustatory characteristics and diverse fruit – ripening periods. For the first time in Bulgaria there were initiated experiments on overcoming the alternative fruit bearing, and on the fertilization in apple orchards with green manure crops. The investigation on the cloneapple rootstocks continued. The conditions for the development of fruit growing in the valleys of the rivers: Struma, Ogosta, Iskar and Mesta were investigated. The researchers participated in the expedition for the creation of forest shelter belts in Dobrudja.
    From October 1951 to the beginning of 1962, Director of the Institute was Assoc. Prof. Georgi Kovachev. He performed two more land settlements. The new land (379da) was exchanged and re-allotted with lands from the State Land Settlement Fund in neighboring villages, so that the total area of the Institute reached 662da. In the territory of the village of Konyavo, Kyustendil district, a new experimental field was established with an area of 52da for experiments with apricot and cherry cultivars.  New trials on agrotechnology and plant protection were commenced, investigating the flower buds differentiation of apple, pear, sweet cherry and apricot cultivars.
    In these experiments the influence of the cultivars, the site conditions, the agrotechnology and rootstock on this phase was studied. The most appropriate to the apple plantations green manure crops, fertilizer norms, timing and modes for apricot grafting, the influence of the autumn tillage on the productivity of apple plantations; the most suitable pre-irrigation moisture of the soil when irrigating apple plantations on M4 rootstock, were determined. The studies on the susceptibility of plum cultivars to sharka and red leaf spot, apple – to apple scab and powdery mildew, pear- to rust, pear scab and brown spot continued. The first practical experiment for dusting of sweet cherry plantations against the cherry fruit fly was performed in 1951. The local pear assortment was studied and three Bulgarian plum cultivars - Osogovska edra, Strumska sinya and Kyustendilska ranna and the peach cultivar 7-14, created at the Institute, were approved. Intensive work on cherry breeding was initiated.
    During the period 1962-1967 Director of the Institute was Prof. Jordan Stoichkov (corresponding member). Prof. Stoichkov made efforts for the modernization of the equipment (laboratories, greenhouses, etc.) and the improvement of the qualification of the staff. The area of the Institute grew by 1000 da, greenhouses were built on 3da, the number of the scientific, subsidiary and administrative staff was increased. In 1965 the Fruit-growing department of the Complex Experimental Station, Negovan, Sofia district, was integrated with the Institute. This department was a direct successor of the Central Agricultural Research Institute (1936-1952), which grew into the Central Institute for Fruit- Growing, Kostinbrod, disbanded in 1953 and transferred to the Experimental Station at Negovan (1963). The first pot experiments with fruit trees were initiated, and the beginning of studies on the architectonics of the root system of apple, pear and plum trees, and the determination of the fertilizer requirements of fruit trees by the use of the foliar diagnostics was set up. Experimental plantations for investigations of the planting systems and shaping, the nutritional and water regimes of apple and pear trees, cultivar- rootstock combinations of sweet cherry and pear trees, were established. The first for Bulgaria experiments for determination of the effect of airplane sprayings against apple scab, codling moth and spider mites were performed. Studies on the biology and means of control of apple powdery mildew, and cherry leaf rollers, were initiated. New cultivars were approved: pear- Pautalia, sweet cherry - Pobeda, Kyustendilska Hrushtyalka and Cherna Konyavska. Investigations on sweet cherry and plum cultivars breeding and genetics were carried out. The creation of dwarf forms of sweet cherry cultivars through the application of ionizing radiation on green cuttings was commenced. . The participation in the zoning of fruit growing in the region of Kyustendil district and other regions was active. Studies on the economical performance of fruit- growing were initiated
    From 1967 to 1972 the Director of the Institute was Prof. Ph. D. Lulcho Hristov. During this period experimental equipment in the territory of the village of Nikolichevci, in the district of Kyustendil, was provided (1969); young research associates (in four specialties) were admitted, and new laboratories established. Virological studies on sweet and sour cherry cultivars and the purposeful use of induced mutagenesis for the acceleration of the breeding process were undertaken. Means of control of the powdery mildew and leaf rollers were established. The new apricot cultivar Festivalna and the pear cultivar Jubileen dar were approved. During the period 1967- 1970 more than 250 fruit tree cultivars and 7 rootstocks were introduced from the USA and Canada. Forty- three of those cultivars were included in the National Standard Assortment List. The construction of a sprinkling irrigation system was started.
    On 01.01.1972 to the post of Director of the Institute was appointed Prof. Stoine Manov. The fruit- growing department at Kostinbrod was separated, and as a unit of its own it grew into the Small Fruit Station, with its Director- Vladimir Ivanov. The new plum cultivar Izobilie was approved. By the use of ionizing radiation, several sweet cherry mutant forms were created. Four sweet cherry rootstocks were selected. The studies on the shaping and pruning of pear and apple cultivars, the most appropriate irrigation regimes, as well as the experiments with different nitrogen fertilizer norms for apple and pear plantations were completed successfully. Valuable information concerning the land management methods was acquired. A significant contribution to the methodology of the foliar diagnostics was made. An impetus was given to the research activity in plant protection, including the virological studies on the sweet cherry studies on the soil fatigue were undertaken in cooperation with the Institute for Fruit-Growing – Pilnitz, Germany. The Institute became a center for the introduction of scientific achievements in fruit growing, and school for improvement of the qualification of the managerial and executive staff. It took the responsibility for the development of sweet and sour cherry, and pear production in the whole country and the apple production in South-Western and North-Western Bulgaria.
    Plans for the construction of 3 apple complexes in the region of Kyustendil were worked out at the Institute - “Dragovishtica“, “Struma” and “Djubrena”, on an area of 29 000 da and sweet cherry - sour cherry belt – on 22 000 da. It was established an effective cooperation with the Institute for Agriculture under Irrigation, Melitopol, Ukraine; the Institute for Fruit-Growing, Skernevice, Poland; the Agro-forest Institute, Skopie, Macedonia.
    On 01.05.1981 as a Director of the Institute was appointed Prof. Ph. D. Kiril Doichev. The efforts for the extending of the research work, improving the qualification of the researchers and the equipment continued. In 1982, after the foundation of the Agricultural Academy, Sofia the Institute for Fruit-Growing, Kyustendil was included in its structure as a separate scientific body. The beginning of the work on mechanization in fruit growing was set, a new researcher started work. In 1985, on an area of 90 da a drip irrigation installation system was constructed and a spectrum of experiments with apple cultivars was undertaken – cultivar–rootstock combinations, irrigation, fertilization and land management. Complexes for rooting of mature and green cuttings and tissue culture with laboratories and adaptation chambers were built. Several laboratories were equipped and put in operation – agrochemistry (2), virology, cytology, physiology and microbiology. Contracts for scientific cooperation with research institutes abroad were signed – Russia, Ukraine, Moldova , Poland, Hungary, Czech Republic, Slovakia , Serbia, Macedonia (former Yugoslavia), Greece and others. Specializations and scientific missions were conducted regularly.
    In November 1989 drastic changes in the politic and socio-economical life in the country occurred. The consecution of reforms and reorganizations affected seriously the Institute. The first considerable consequence gave birth to the “Law of the reinstatement of the property on agricultural lands” and its realization. The experimental base was disbanded and liquidated; its property given to the “Liquidation Council”. There was a dramatic deterioration in the financial status. The area of the owned land under management was decreased to 385da.
    In March 1991 assoc. Prof. Ph. D Zdravcho Makariev became the Director of the Institute. In 1993, two specialists from the USA worked at the Institute for a period of six months – Larry Holsy and Allan Lines. With their assistance the “Extension service” was established and 3 researchers, 1 engineer and 1 technician from the staff attached.
    On 20.04.1993 Prof. Ph.D. Dimitar Domozetov became the Director of the Institute. The efforts to retain the status of the Institute were crowned with success. The number of the staff (previously brought to its minimum) increased. New work positions were opened up and competitions announced in accordance with the actual needs of the Bulgarian agriculture.
    Patents “Method for localized fertilization of perennial plantations, more specifically apples” and patent “Means for stimulation of plant root formation” were approved and “Technology for apple production under drip irrigation” was accepted.
 Efforts for additional land settlement were made and after an examination by a special auditing committee to the Ministry of Agriculture some more land from the State Land Fund was given to the Institute – 19da from the territory of the village of Gorna Grashtitza, the “Drenov dol” region, at Kyustendil – 30da, at the villages of Gorna Koznica – 50.2da, Zgurovo – 81.5 da and Bersin – 15.3 da   – about 196da, altogether.
    In 2000 the Institute for Fruit-Growing, Kyustendil, the Complex Experimental Station, Sandanski, and the Experimental Station of Small Fruit Crops, Kostinbrod were transformed and united into the Institute of Agriculture, Kyustendil. Several months later, the Complex Experimental Station, Sandanski was taken out from the structure of the Institute of Agriculture, Kyustendil. In 2006 the Cultivar Experimental Station in Bagrentzi was transferred to the Institute and the cultivable lands increased with another 120da.
    The establishment of gene-banks for apple, sweet and sour cherry, and plum was undertake. The sweet cherry cultivars Danelia and Stefania and the sweet and sour cherry rootstocks - IK-M8 and IK-M9 were approved by the State Assortment Commission, as well as a plum cultivar Kyustendilska krasavitza. A new sweet cherry cultivar and five apple hybrids are submitted to be accepted. As a result of the introductory and breeding work a rich gene-stock of more than 800 cultivar samples have been collected. More than 1500 hybrids are in process of investigation, whereas selected as perspective are 63 apple hybrids, 59 sweet  cherry hybrids, 8 sour cherry hybrids, 5 strawberry, 4 black currant and 3 grape hybrids. The apple cultivar Monro, the sour cherry cultivars Feratzida  and Dwarf rich and the sweet cherry cultivars Ohridska priusadebnaia are also selected to be perspective. As a perspective cultivars with a field resistance to sharka were selected Chachanska nai-bolya, Chachanska lepotica, Valevska, Ashatan and Pacific. Two new cross-incompatible groups of the sweet cultivars Kozerska and Germersdorfska with Bulgarska hrushtalka and Bing, Napoleon, Lambert and Star with Ohridska were established. The sour cherry gathering period was extended from 35 to 75 days. The tissue and embryo-culture methods for the selection of new early and over-early ripening cultivars, and such, resistant to abiotic stress factors and their rapid reproduction were used. The most appropriate for the sweet cherry nitrogen fertilizer forms and norms were established. An improved technology for sweet cherry growing in three technological variants was suggested - fallow with organic and mineral fertilization, fallow with mineral fertilization and shrubby crown. The newest raspberry cultivars Lyulin and Samodiva are offered with specific technologies as a totally completed research product. The work on the collection and creation of a collection plantation of table cultivars of vine, their investigation in the ecological conditions of the region and technologies for broccoli cultivating are in its initial stage.
    Two research products for introduction in practice - establishment and cultivation of apple and sweet cherry plantations were approved.