Lavender cultivation in Bulgaria – 21st century developments, breeding challenges and opportunities

Abstract

Bulgaria has a near century long tradition in lavender (Lavandula angustifolia Mill) cultivation and essential oil production.Following significant reduction of lavender plantations during the country’s transition period at the end of the last century, the industrial lavender cultivation gained considerable attention and rapid expansion during the last decade.Here we present the main trends of the 21st century developments of the industrial lavender cultivation in Bulgaria.The data of parallel growing and essential oil production of the currently cultivated Bulgarian lavender varieties demonstrate the higher impact of cultivating vegetative propagated varieties instead of seed derived lavender populations.The main directions and challenges of the 21st century lavender growing in the country related to increased lavender cultivation are pointed out.The recent advances in development of lavender genomic resources, molecular markers, comparative analysis of flower volatiles and related opportunities for targeted breeding and marker assisted selection are discussed. © 2016, National Centre for Agrarian Sciences.All rights reserved.

Full text

584
Bulgarian Journal of Agricultural Science, 22 (No 4) 2016, 584–590
Agricultural Academy
LAVENDER CULTIVATION IN BULGARIA – 21ST CENTURY DEVELOPMENTS, BREEDING
CHALLENGES AND OPPORTUNITIES
S. STANEV1, T. ZAGORCHEVA2 and I. ATANASSOV2*
1 Agricultural Academy, Institute of Roses and Aromatic Plants, BG-6100 Kazanlak, Bulgaria
2 Agricultural Academy, AgroBioInstitute, BG-1164 Sofi a, Bulgaria
Abstract
STANEV, S., T. ZAGORCHEVA and I. ATANASSOV, 2016. Lavender cultivation in Bulgaria – 21st century devel-
opments, breeding challenges and opportunities. Bulg. J. Agric. Sci., 22: 584–590
Bulgaria has a near century long tradition in lavender (Lavandula angustifolia Mill) cultivation and essential oil produc-
tion. Following signifi cant reduction of lavender plantations during the country’s transition period at the end of the last century,
the industrial lavender cultivation gained considerable attention and rapid expansion during the last decade. Here we present
the main trends of the 21st century developments of the industrial lavender cultivation in Bulgaria. The data of parallel growing
and essential oil production of the currently cultivated Bulgarian lavender varieties demonstrate the higher impact of cultivat-
ing vegetative propagated varieties instead of seed derived lavender populations. The main directions and challenges of the
21st century lavender growing in the country related to increased lavender cultivation are pointed out. The recent advances in
development of lavender genomic resources, molecular markers, comparative analysis of fl ower volatiles and related opportu-
nities for targeted breeding and marker assisted selection are discussed.
Keywords: Lavandula angustifolia, lavender varieties, Bulgaria, cultivation, essential oil, targeted breeding
Abbreviations: EST – Expressed Sequence Tag; SSR – Simple Sequence Repeat; SRAP – Sequence-Related Ampli-
fi ed Polymorphism; GC/MS – Gas Chromatography/ Mass Spectrometry
*E-mail: ivan_atanassov@abv.bg; sdstanev@abv.bg, tzvetelina.zagorcheva@gmail.com
Introduction
Lavender is a perennial sub-shrub plant that belongs to the
mint family (Lamiaceae) and is native to the Mediterranean
region. The genus Lavandula includes above 30 fl owering
species, but only three of them are industrially cultivated for
production of essential oil: lavender (Lavandula angustifolia
Mill.), spike lavender (Lavandula latifolia L.) and lavandin - a
sterile hybrid developed by crossing L. angustifolia × L. latifo-
lia (Lis-Balchin, 2002; Lesage-Meessen et al., 2015). Laven-
der is cultivated worldwide in a number of countries, as some
of the main lavender oil producers are Bulgaria, France, UK,
China, Spain and others. During the last few years the volumes
of lavender oil produced in Bulgaria steadily exceed those of
France and the country becomes the world’s top lavender oil
producer, growing over 6000 ha of different lavender varieties.
Lavandin is mainly cultivated in France, which supplies 90%
of the world production of lavandin oil. The main spike laven-
der cultivation and essential oil production are located in Spain.
Lavender oil is considered of higher quality in comparison to
lavandin oil and it is marketed at around 3–5 times higher price.
Both lavender and lavandin essential oils have a wide range of
applications in various industrial products including perfumes,
pharmaceuticals, cosmetics, as well as, personal care and home
maintenance products (Cavanagh and Wilkinson, 2005; Les-
age-Meessen et al., 2015). Additionally, lavender oil has been
increasingly applied in aromatherapy and integrative medicine
due to its positive effect for treatment of anxiety, insomnia and
hair loss (Lis-Balchin and Hart, 1999; Cavanagh and Wilkin-
son, 2002; Kashani et al., 2011; Sienkiewicz et al., 2011; Soltani
et al., 2013). All this makes lavender oil a valuable ingredient
and stimulates the expansion of lavender cultivation and essen-

585
Lavender Cultivation in Bulgaria – 21St Century Developments, Breeding Challenges and Opportunities
tial oil production.
In Bulgaria, the industrial cultivation involves only the com-
mon lavender, while lavandin is grown in limited areas without
economic signifi cance. Lavender cultivation has been intro-
duced in the country for the fi rst time during 1903 by Konstantin
Malkov, the famous agronomist and founder of the agricultural
science in the country. After his death the established lavender
plantation were abandoned for more than a decade and laven-
der cultivation was re-initiated by the agronomist Konstantin
Georgiev in 1925 using some of the survived lavender bushes.
The fi rst large lavender plantations were established in the areas
around Kazanlak and Karlovo within the next few years using
locally produced planting material and newly imported seeds
from England and France (Georgiev, 1964). Since then, the
lavender cultivation in Bulgaria has passed through periods of
changing agricultural practices and expansion and reduction of
the planted areas, which was heavily infl uenced by the overall
country development.
Here we present the recent developments of lavender culti-
vation in Bulgaria, as well as, the impact of growing Bulgarian
lavender varieties. The main challenges of lavender improve-
ment and possibility for targeted breeding and application of
marker assisted selection are discussed.
21st century developments of lavender cultivation in Bul-
garia
During the 20th century, industrial lavender cultivation be-
came one of the well-established sectors of the Bulgarian agri-
culture and the lavender planted areas exceeded 7000 ha in the
beginning of the 70’s. During the second half of the last century
nearly all the lavender cultivation was carried out by the typical
for this time cooperatives. The lavender oil was distilled and
exported by the state owned companies. The transition period
during the 1990s in Bulgaria had a strong negative impact on
the lavender-growing and essential oil distillation industry. The
wavering and slow implementation of the agricultural reforms
during the transition period resulted in a decade without signifi -
cant renovation of the existing and establishment of new laven-
der plantations. This led to nearly fi vefold decrease of the areas
of lavender plantations, reduced quality of the planting material
and capacity for establishment of new plantations, Figure 1.
The stabilization and recovery of the Bulgarian economy
started from the beginning of the 21st century bringing positive
development and structural changes in the lavender cultiva-
tion and essential oil production. During the transition period
the lavender plantations and essential oil distillation facilities
became again a private property. EC Operational Programs
supported by the Agriculture State Fund brought substantial
new investments into the renovation and establishment of new
lavender cultivation areas and oil distillation facilities. All this
resulted in expansion of the country regions of lavender cultiva-
tion beyond the traditional ones. While during the last century
lavender was mainly cultivated in South Bulgaria, in the regions
of Stara Zagora, Plovdiv, Pazardzhik and Blagoevgrad, now it
is cultivated in nearly all country regions including the North
Bulgarian regions of Vidin, Veliko Turnovo, Shumen, Dobrich
and Varna. Accordingly, the total areas of lavender cultivation
grew rapidly during the last decade reaching 6892 ha in 2014,
Figure 1. This placed Bulgaria as the world top lavender grower
and essential oil producer. Lavender fl ower yields are heavily
infl uenced by the environmental factors, ranging from 175 kg/
da to 259 kg/da for the period 2005 – 2014 Figure 2. In spite of
the year to year variations, the average yield of the harvested
lavender fresh fl ower stalks grew during last few years reaching
259 kg/da for the 2014 campaign.
Lavender improvement and variety cultivation
The increased lavender cultivation and essential oil produc-
tion in Europe during the fi rst half of the last century stimulated
Fig. 1. Total area (ha) of lavender cultivation in Bulgaria
Fig. 2. Average fl ower yields from lavender plantations
in Bulgaria during 2005–2014 period
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
1971–
1975
1975–
1990
1990–
1998
1998–
2001
2001–
2004
2005–
2008
2009–
2012
2013
2014

586 S. Stanev, T. Zagorcheva and I. Atanassov
the initiation of lavender improvement in France and the former
Soviet Union (Russia, Ukraine and Moldova). The improve-
ment programs targeted a wide range of lavender characteristics
including fl ower yield, essential oil content and quality, con-
tent of linalyl acetate and cold tolerance. Initially the lavender
improvement involved mainly testing, selection and propaga-
tion of best performing seed-derived plants. Later the breeders
studied the effect of heterosis following hybridization between
different varieties and breeding lines, as well as applying ex-
perimental polyploidy, chemical and radiation mutagenesis
(Louzina, 1968; Romanenko, 1973; Singh et al., 1989).
In Bulgaria, lavender improvement started in the 1950’s
(Dimitrova, 1959) and signifi cantly expanded during the next
four decades following the activities of the breeders from the
Institute of Roses and Aromatic Plants (IRAP), Kazanlak. The
studies involved clonal selection, intraspecifi c hybridization,
gamma-irradiation, chemical mutagenesis and resulted in de-
velopment of more than ten highly productive lavender varieties
producing high quality essential oil (Dimitrova, 1959; Topalov,
1962; Topalov, 1969; Raev and Boyadzhieva, 1988; Staikov
and Boyadzhieva, 1989). During the last decade, the research-
ers from IRAP continued to study clones and seed offspring of
the country’s most cultivated lavender varieties and to develop
new varieties (Stanev 2007, 2010). Currently, lavender cultiva-
Table 1
Flower yield and essential oil content and yield of six Bulgarian lavender varieties and seed population
Parameters Lavender varieties and seed population
Hemus
Druzhba
Sevtopolis
Yubileina
Raya
Hebar
Seed
population
Flower yields (kg/da) 560 ± 54 637 ± 61 625 ± 62 554 ± 52 673 ± 66 755 ± 71 588 ± 51
Content of essential oil (% of the fl ower weight) 1.6 ± 0.2 1.8 ± 0.4 2.0 ± 0.5 2.2 ± 0.2 2.6 ± 0.4 2.3 ± 0.5 0.9 ± 0.2
Yield of essential oil (kg/da) 9.0 ± 1.0 11.5 ± 1.3 12.5 ± 1.5 12.2 ± 1.2 17.5 ± 1.7 17.4 ± 1.9 5.3 ± 0.6
The presented data refer the three years period 2005–2007 and were collected from 3–5 year old lavender plantations. located in the
experimental fi eld of IRAP. The lavender plants were cultivated according to technology of growing commonly use in Bulgaria
Table 2
Ranges of relative contents of main compounds of essential oils distilled from fresh fl oral stalks of six Bulgarian laven-
der varieties and seed population
Compound
(range for Bulgarian lavender
oil according to ISO3515:2002
specifi cation)
Ranges of FID pick area percentages of lavender oil compounds (%)
Hemus
Drujba
Sevtopolis
Jubileina
Raya
Hebar
Seed
population
Lynalyl acetate (30–42%) 26.7–37.9 30.9–35.3 25.6–28.4 28.6–31.3 31.3–33.6 28.4–35.4 28.4–32.0
Linalool (22–34%) 30.5–39.8 31.3–33.9 22.2–31.6 24.0–29.5 33.6–35.6 27.2–28.7 30.2–32.3
Lavandulyl acetate (2–5%) 2.3–3.0 1.0–1.3 4.4–4.8 4.0–5.3 4.2–4.7 3.1–3.7 4.2– 5.1
Lavandulol (> 0.3%) 0.7–1.1 0.3–2.9 0.4–1.8 0.1–1.1 0.4–1.2 0.2–1.3 0.3– 0.9
Camphor (< 0.6%) 0.2–0.5 0.2–0.3 0.2–0.5 0.1–0.3 0.2–0.4 0.3–0.5 0.2– 0.4
Terpinen-4-ol (2 – 5%) 0.2–4.3 2.5–2.9 0.3–1.8 1.7–8.8 0.4–2.8 0.2–3.3 1.5– 3.2
Eucalyptol (< 2%) 2.8–3.2 0.2–1.7 1.4–5.5 0.4–0.5 1.3–2.3 0.8–3.8 1.3– 1.7
cis-Ocimene (3–9%) 1.7–2.2 1.7–5.9 0.2–1.9 2.7–7.2 1.9–3.0 2.1–6.9 2.9– 3.8
trans-Ocimene (2–5%) 1.0–1.7 1.3–4.9 1.0–2.9 1.6–5.4 0.2–2.4 1.9–5.7 1.6– 2.4
The relative content of each compound correspond to FID pick area percentage from GC-FID chromatograms. The presented data refer
the range of relative contents of each compound determined for essential oils produced from 3–5 year old lavender plantations sampled for
three years period 2005–2007

587
Lavender Cultivation in Bulgaria – 21St Century Developments, Breeding Challenges and Opportunities
tion in the country involves mainly seven varieties developed
during the last century namely: Hemus, Druzhba, Karlovo, Sev-
topolis, Yubileina, Raya and Hebar. The varieties are planted in
all lavender cultivations regions. A steady increase of the areas
planted with the varieties Hemus and Sevtopolist is observed
during the last few years.
The cultivation of selected lavender varieties, instead of
population of seed derived lavender plants or propagated old
lavender populations, resulted in an increase of both lavender
fl ower and essential oil yields. The data presented in Table 1
demonstrate the impact of growing vegetative propagated
lavender varieties in comparison to the seed derived lavender
population. The results of the study show 6% to 30% increase
of the fl ower yield for four of the tested varieties and between
twofold to above threefold increase of the essential oil yield
in comparison to the lavender seed population. The last is due
mainly to the signifi cant, above two fold, increase of the es-
sential oil content in the infl orescence of the tested varieties.
The further comparison of the essential oil composition distilled
from infl orescence material of the studied varieties shows that
the relative content of nearly all compounds lies well within the
ranges specifi ed by the international ISO3515:2002 standard
for high quality Bulgarian lavender oil of population and clonal
lavender, Table 2. The closer observation shows relatively large
variations of the essential oil composition of the cultivated Bul-
garian lavender varieties, which makes possible the production
of quality blends from varietal essential oils. The described data
clearly demonstrate the advantages of growing selected supe-
rior lavender varieties, well adapted to the local environmental
and microclimate conditions.
It is worth noted that Bulgarian lavender varieties, are also
cultivated and are a subject of additional studies in other coun-
tries, as well. For example, lavender cultivation in Romania was
initiated during the last century using Bulgarian varieties and
var. Karlovo became predominantly cultivated in this country
for a long period (Pohrib and Nistor, 2012). Bulgarian lavender
varieties are also cultivated in Turkey. A recent study involving
lavender varieties planted in Isparta region Turkey, showed that
the Bulgarian Raya and Vera varieties surpass the other tested
varieties in qualitative and quantitative traits (Kara and Baydar,
2013). In another study, the varieties Druzhba, Hemus and Raya
were shown to have high enantiomeric purity of linalool and
linalyl acetate (Baser et al., 2005). Most of the Bulgarian variet-
ies are also characteristic with high adaptability to unfavorable
environmental conditions and two of them, namely Hemus and
Raya show elevated yield stability under cultivation at subop-
timal conditions (Stanev, 2010). Bulgarian varieties have also
been used as a base for selection and improvement in geograph-
ically remote countries, for example CIMAP Regional Centre,
Kashmir, India, where var. Karlovo was initially introduced
for cultivation in 1978 and later used in improvement program
(Singh et al., 1989).
Directions and challenges of lavender cultivation
The increased lavender cultivation in Bulgaria during the
21st century resulted in changes of the applied agricultural and
fl ower harvesting practices, which requires implementation of
specifi c actions to provide further sustainable development of
lavender growing and essential oil production in the country
and keeping its position as world top producer and supplier of
quality lavender oil. Some of the main directions and develop-
ments of the 21st century lavender cultivation in Bulgaria and
related challenges include:
Mechanization of lavender growing and processing. The in-
creased total area of cultivation and enlargement of the lavender
plantations led to a steady increase and presently nearly com-
plete mechanization of the lavender agricultural practices in-
cluding tilling and fl ower harvesting. Accordingly, there are in-
creasing demands of growing lavender varieties with improved
plant architecture, which facilitates machine tillage and fl ower
harvesting. Desired features of such varieties are the erected
growth habit and long solid fl ower stalks not lying down on
the ground, which makes possible the effi cient machine tilling
and fl ower harvesting without signifi cant damages of the plants.
Lavender varieties better adapted to the local environmen-
tal conditions. The expansion of the total lavender areas during
the last decade in Bulgaria is related with increasing cultivation
outside the traditional areas of growing lavender in the coun-
try. Often the local soil characteristics and/or climate conditions
in the new regions of lavender cultivation are not optimal for
the currently available and cultivated varieties, which results
in large variations of fl ower and essential oil yields, as well as
lower lavender oil quality in some „bad” years. This requires
additional parallel growing and testing of the existing pool of
varieties and superior breeding lines and selection of the best
performing for the new regions, or initiation of new lavender
improvement program focused on specifi c regions. The testing
and improvement work has to consider both adaptability of the
tested varieties and breeding lines and stability of a number of
growth parameters, fl ower and essential oil yields and essential
oil quality (Stanev 2010).
Flower yield, essential oil content and quality. The further
improvement production parameters and increase of fl ower and
essential oil yields are a permanent task for lavender producers
in the country. However, their pursuit is largely complicated by
the demand the improvement to be combined with preserva-
tion of the high lavender oil quality. The complex genetic back-
ground of these parameters requires further research on genes
and alleles related to biosynthesis of lavender essential oil com-
pounds and employment of the gained information in marker

588 S. Stanev, T. Zagorcheva and I. Atanassov
assisted selection of new superior varieties.
New products driven lavender cultivation. So far the lav-
ender cultivation in Bulgaria was directed mainly to essential
oil production through steam distillation and direct export of
the lavender oil. During the last decade there has been an in-
creased interest and demands for development of new innova-
tive lavender products, as well as wider application of other
extraction technologies like solvent or supercritical carbon
dioxide extractions. Although the currently available lavender
varieties provide quality fl ower material for application of mod-
ern extraction technologies and new product development, it
could be speculated that there is a need for additional lavender
improvement and development of new varieties better suited
to particular extraction technology and/or innovative product
manufacture.
Certifi ed planting material and quality check. The results
of parallel cultivation of lavender varieties and seed population
presented above clearly indicate, that the use of homogenous,
vegetative propagated planting material for renovation or es-
tablishment of new lavender plantations signifi cantly increase
both fl ower and essential oil yields. The structural changes in
the Bulgarian agriculture during the transition period were also
related to changes in the model of production and farmers sup-
ply with lavender planting material. The centralized production
and distribution of lavender planting material in the country by
IRAP during the second half of the last century is presently sub-
stituted with free market offering of planting material produced
by a number of small producers. This raises the questions about
the proper maintenance of the collections of lavender varieties,
breeding lines and lavender genetic resources, as well as the
restoration of the last century operating system for production
of pre-basic, basic and standard propagation materials. Addi-
tionally, at present there are no well-established practices and
service for quality check of the lavender planting material in
the country. This makes possible the offering and cultivation
of low quality seed derived planting material or such of mixed
varieties. The expected increased utilization of a larger number
of varieties and lines adapted to local environmental conditions
in the future will lead to increased demands of certifi ed vegeta-
tive propagated planting material and affordable quality check
services.
Lavender genomic resources and opportunities for mark-
er assisted lavender improvement
The increased complexity of the lavender improvement
tasks pointed above requires future applications of targeted
breeding rather than current testing and selection of better per-
forming mutant clones or plants from seed derived populations.
The implementation of lavender targeted breeding programs
requires additional development of molecular markers suited
for marker assisted selection, as well as effi cient procedure for
routine comparative analysis of lavender fl ower volatiles. In
spite of the economic importance of lavender and other genus
Lavandula members, genomic resources and molecular mark-
ers suitable for characterization of lavender genetic resources
and targeted breeding started to be developed only during the
last decade. The reported characterization of lavender leaf and
fl ower EST sets by Lane et al. provides a solid ground for de-
velopment of lavender as a model system to study molecular
regulation of essential oil biosynthesis supported by adequate
genomic resources (Lane et al. 2010). An essential extension
of this research was the development of EST-SSR markers and
successful testing of their Lavandula species transferability,
which is an important step towards development of effi cient
molecular markers for genetic resources assessment and tar-
geted breeding (Adal et al. 2015). Molecular markers for La-
vandula species were reported by other authors as well, but
they were used in biodiversity and phylogenetic studies and are
with limited applications for targeted breeding (Chunshan et
al. 2009; Bräuchler et al. 2010). Our recent studies for search-
ing of affordable genome wide markers demonstrated that
SRAP markers could be effi ciently used for genetic diversity
assessment and also have potential for targeted breeding ap-
plications (our unpublished work). Another important step in
the development of effi cient lavender genomic resources was
the reported characterization a number of key genes involved
in lavender essential oil biosynthesis (Landmann et al., 2007;
Demissie et al., 2011; Landmann et al., 2011; Demissie et al.,
2012; Sarker et al., 2012; Sarker et al., 2013; Jullien et al., 2014;
Benabdelkader et al., 2015; Sarker and Mahmoud, 2015). The
expression studies of several lavender terpene synthases sug-
gest they have complex spatial and temporal expression pro-
fi les, but terpene synthase activities in lavender infl orescence
appear to be generally regulated at transcriptional level (Tholl,
2006; Guitton et al., 2010; Lane et al., 2010). The above makes
realistic to employ the available and further generated knowl-
edge about lavender essential oil genes for implementation of
a targeted breeding program in order to: /a/ retain the lavender
essential oil quality in parallel to improving of other agronomic
traits or /b/ to carry out targeted metabolic engineering of es-
sential oil biosynthesis for production of specifi c lavender es-
sential oils. The available gene sequence data make possible the
ready identifi cation of gene-/allele- specifi c SNP markers in the
available lavender varieties and breeding lines. For example,
the direct sequencing of PCR amplifi ed genomic DNA frag-
ments of a trans-alpha-bergamotene synthase gene from seven
Bulgarian lavender varieties results in identifi cation of a set of
SNPs which distinguish all tested varieties and could be used
for analysis of SNP allelic confi gurations of this gene in plants
from segregating populations, (our unpublished work). Putting

589
Lavender Cultivation in Bulgaria – 21St Century Developments, Breeding Challenges and Opportunities
together the three types of markers, EST-SSR, SRAP and gene
specifi c SNP, offer a solid base for initiation of effi cient targeted
breeding programs using marker assisted selection.
Employing effi cient procedure for comparative analysis of
fl ower volatiles of larger number of lavender lines is the other
essential factor for a successful targeted breeding program. So
far the testing and selection of lavender lines and varieties in-
volves analysis of the lavender essential oil rather than direct
analysis of fl ower volatiles (Laurence, 1988; Raev and Boy-
adzhieva, 1988; Staikov and Boyadzhieva, 1989; Baser et al.,
2005; Muñoz-Bertomeu et al., 2007; Kara and Baydar, 2013).
Although the essential oil analysis provides data of direct practi-
cal application and allows assessment of the lavender oil minor
compounds, the composition of the lavender oil largely depends
and varies with the distillation parameters, fl ower harvest and
processing practices (Angioni et al., 2006; Cassel et al., 2009;
Zheljazkov et al., 2013; Hassiotis et al., 2014; Dušková et al.,
2016). This signifi cantly hampers the use of lavender oil analy-
sis for a precise comparison of the volatiles composition of the
tested lavender lines. Additionally, the routine application of
lavender oil analysis is complicated by the need to process in
parallel a larger number of samples related to characterization
of the tested populations. Our fi rst attempt to develop routine
procedure for analysis of lavender fl ower volatiles, employing
milling and extraction of frozen lavender infl orescences, shows
high variations of the compound abundances in replica analy-
ses suggesting it can’t be used for comparative analysis (Zago-
rcheva et al., 2013). Recently we successfully tested a simple
fl ower extraction procedure followed by direct GC-MS analysis
of extracts (our unpublished work). The procedure is well suited
for routine comparative analysis of a large number of lavender
plants, characterization of lavender populations or to study the
effect of various environmental and agriculture factors.
Conclusion
The data presented in this review displays the rapid increase
of lavender cultivation in Bulgaria during the 21st century,
which resulted in the country becoming the world top producer
and supplier of lavender oil. The data of parallel cultivation and
essential oil extraction demonstrates the higher impact of grow-
ing Bulgarian lavender varieties instead of seed derived laven-
der populations. The increased lavender cultivation resulted in
changes of the lavender growing and fl ower harvesting prac-
tices, suggesting new direction and challenges of lavender im-
provement. This poses elevated demands on application of lav-
ender targeted breeding programs employing marker assisted
selection and a larger scale comparative analysis of lavender
fl ower volatiles. The recent developments in lavender genomic
and molecular marker resources provide solid ground for deep-
er characterization of the available genetic resources and initia-
tion of targeted breeding programs directed towards the main
challenges of lavender improvements.
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Received June, 1, 2016; accepted for printing June, 17, 2016