ArticlePDF Available

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

Authors:

Abstract and Figures

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.
Content may be subject to copyright.
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-
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
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
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
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-
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
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
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
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.
References
Adal , A., Z. Demissie and S. Mahmoud, 2015. Identifi cation, vali-
dation and cross-species transferability of novel Lavandula EST-
SSRs. Planta, 241 (4): 987–1004.
Angi oni, A., A. Barra, V. Coroneo, S. Dessi and P. Cabras, 2006.
Chemical composition, seasonal variability, and antifungal activity
of Lavandula stoechas L. ssp. stoechas essential oils from stem/
leaves and fl owers. Journal of Agricultural and Food Chemistry,
54 (12): 4364–4370
Base r, K., T. Özek and A. Konakchiev, 2005. Enantiomeric distribu-
tion of linalool, linalyl acetate and camphor in Bulgarian lavender
oil. Journal of Essential Oil Research, 17 (2):135–136
Benab delkader, T., Y. Guitton, B. Pasquier, J. Magnard, F. Jullien,
A. Kameli and L. Legendre, 2015. Functional characterization of
terpene synthases and chemotypic variation in three lavender spe-
cies of section Stoechas. Physiologia Plantarum, 153 (1): 43–57
Bräuchler, C., H. Meimberg and G. Heubl, 2010. Molecular phy-
logeny of Menthinae (Lamiaceae, Nepetoideae, Mentheae)–tax-
onomy, biogeography and confl icts. Molecular Phylogenetics and
Evolution, 55 (2): 501–523.
C assel E., R. Vargas, N. Martinez, D. Lorenzo and E. Dellacassa,
2009. Steam distillation modeling for essential oil extraction pro-
cess. Industrial Crops and Products, 29 (1): 171–176.
C avanagh, H. and J. Wilkinson, 2002. Biological activities of laven-
der essential oil. Phytotherapy Research, 16 (4): 301–308.
C avanagh, H. and J. Wilkinson, 2005. Lavender essential oil: a re-
view. Healthcare Infection, 10 (1): 35-37.
C hunshan, C., C. Guojun, M. Baoru, Z. Tianfu and L. Juan, 2009.
Introduction and Breeding & Cultivation Techniques of Lavender
(Lavandula spp.)[J]. Chinese Wild Plant Resources, 6: 20-25.
D emissie, Z., M. Cella, L. Sarker, T. Thompson, M. Rheault and
S. Mahmoud, 2012. Cloning, functional characterization and
genomic organization of 1, 8-cineole synthases from Lavandula.
Plant Molecular Biology, 79 (4–5): 393–411.
D emissie, Z., L. Sarker and S. Mahmoud, 2011. Cloning and func-
tional characterization of β-phellandrene synthase from Lavandula
angustifolia. Planta, 233 (4): 685–696.
Di mitrova, E., 1959. Nature of inheritance during seed propagation
of Lavandula vera L. Use of seedling generation obtained by free
pollination in selection and seed production. Compte Rendu of the
Institute of Horticulture, 8: 12–23 (Bg).
Du šková, E., K. Dušek, P. Indrák and K. Smékalová, 2016. Posthar-
vest changes in essential oil content and quality of lavender fl ow-
ers. Industrial Crops and Products, 79: 225–231.
Georgi ev, K., 1964. History of the experimental station for roses and
essential oil bearing plants in Kazanlak. Bulletin of the Develop-
ment of the Essential Oil Industry, 8: 1–25 (Bg).
Guitto n, Y., F. Nicolè, S. Moja, N. Valot, S. Legrand, F. Jullien and
L. Legendre, 2010. Differential accumulation of volatile terpene
590 S. Stanev, T. Zagorcheva and I. Atanassov
and terpene synthase mRNAs during lavender (Lavandula angus-
tifolia and L. x intermedia) infl orescence development. Physiolo-
gia Plantarum, 138 (2): 150–163.
Hassiot is, C., F. Ntana, D. Lazari, S. Poulios and K. Vlachonasios,
2014. Environmental and developmental factors affect essential oil
production and quality of Lavandula angustifolia during fl owering
period. Industrial Crops and Products, 62: 359–366.
Jullien , F., S. Moja, A. Bony, S. Legrand, C. Petit, T. Benabdelkad-
er, K. Poirot, S. Fiorucci, Y. Guitton and F. Nicolè, 2014. Isola-
tion and functional characterization of a τ-cadinol synthase, a new
sesquiterpene synthase from Lavandula angustifolia. Plant Mo-
lecular Biology, 84 (1-2): 227–241.
Kara, N. and H. Baydar, 2013. Determination of lavender and lavan-
din cultivars (Lavandula sp.) containing high quality essential oil
in Isparta, Turkey. Turk. J. Field Crops, 18: 58–65.
Kashani, M., M. Tavirani, S. Talaei and M. Salami, 2011. Aqueous
extract of lavender (Lavandula angustifolia) improves the spatial
performance of a rat model of Alzheimer’s disease. Neuroscience
Bulletin, 27 (2): 99-106.
Landmann, C., B. Fink, M. Festner, M. Dregus, K.-H. Engel and
W. Schwab, 2007. Cloning and functional characterization of
three terpene synthases from lavender (Lavandula angustifolia).
Archives of Biochemistry and Biophysics, 465 (2): 417–429.
Landmann, C., S. Hücherig, B. Fink, T. Hoffmann, D. Dittlein, H.
Coiner and W. Schwab, 2011. Substrate promiscuity of a ros-
marinic acid synthase from lavender (Lavandula angustifolia L.).
Planta, 234 (2): 305–320.
Lane, A., A. Boecklemann, G. Woronuk, L. Sarker and S. Mah-
moud, 2010. A genomics resource for investigating regulation of
essential oil production in Lavandula angustifolia. Planta, 231 (4):
835–845.
Laurence, B., 1988. Progress in Essential Oils. Lavender Oil. Perf .
Fl., 12 (6): 64–70.
Lesage-Mee ssen, L., M. Bou, J.-C. Sigoillot, C. Faulds and A. Lo-
mascolo, 2015. Essential oils and distilled straws of lavender and
lavandin: a review of current use and potential application in white
biotechnology. Applied Microbiology and Biotechnology, 99 (8):
3375–3385.
Lis-Balchi n, M., 2002. Lavender: the Genus Lavandula. Taylor and
Francis, London, 283 pp.
Lis-Balchi n, M. and S. Hart, 1999. Studies on the mode of action of
the essential oil of Lavender (Lavandula angustifolia Mill.). Phy-
totherapy Research, 13 (6): 540-542.
Louzina, L. , 1968. Lavender selection. Works of the All-Union Insti-
tute of Essential Oil Bearing Crops, 1: 128–134 (Ru).
Muñoz-Berto meu. J., I. Arrillaga and J. Segura, 2007. Essential
oil variation within and among natural populations of Lavandula
latifolia and its relation to their ecological areas. Biochemical Sys-
tematics and Ecology, 35 (8): 479–488.
Pohrib, E.-L . and E. Nistor, 2012. Spikes of azure bloom: lavender
– history and stories. Scientifi c Papers. Series A. Agronomy, 55:
397–405.
Raev, R. and B. Boyadzhieva, 1988. Newly developed lavender culti-
vars Sevtopolis and Yubilejna. Proceedings Scientifi c Conference,
Stara Zagora, 26–27 May, Bulgaria (Bg).
Romanenko, L ., 1973. Combining ability of lavender lines. Works of
the All-Union Institute of Essential Oil Bearing Crops, 6: 38–42
(Ru).
Sarker, L., Z. Demissie and S. Mahmoud, 2013. Cloning of a ses-
quiterpene synthase from Lavandula x intermedia glandular tri-
chomes. Planta, 238 (5): 983–989.
Sarker, L., M. Galata, Z. Demissie and S. Mahmoud, 2012. Molec-
ular cloning and functional characterization of borneol dehydro-
genase from the glandular trichomes of Lavandula x intermedia.
Archives of Biochemistry and Biophysics, 528 (2): 163–170.
Sarker, L. a nd S. Mahmoud, 2015. Cloning and functional charac-
terization of two monoterpene acetyltransferases from glandular
trichomes of L. x intermedia. Planta, 242 (3): 709–719.
Sienkiewicz, M., M. Lysakowska, J. Ciecwierz, P. Denys and E.
Kowalczyk, 2011. Antibacterial activity of thyme and lavender es-
sential oils. Medicinal Chemistry, 7 (6):,674–689.
Singh, A., J . Singh and S. Sharma, 1989. Multivariate Analysis in
Relation to Genetic Improvement in Lavender, Lavandula offi ci-
nalis Chaix. Plant Breeding, 102 (4): 302–305.
Soltani, R., S. Soheilipour, V. Hajhashemi, G. Asghari, M. Bagheri
and M. Molavi, 2013. Evaluation of the effect of aromatherapy
with lavender essential oil on post-tonsillectomy pain in pediatric
patients: a randomized controlled trial. International Journal of Pe-
diatric Otorhinolaryngology, 77 (9): 1579–1581.
Staikov, V. and B. Boyadzhieva, 1989. Hemus. Newly developed
highly productive lavender cultivar. Horticultural Sciences, 26 (1):
31–34 (Bg).
Stanev, S., 2007. Alternative approach for vegetative propagation of
lavender. Scientifi c Conference: 100 Years of Experimental and
Scientifi c Work with Essential Oil Bearing and Medicinal Crops in
Bulgaria, 1-2, June, Kazanlak, pp. 206–210 (Bg).
Stanev, S., 2010. Evaluation of the stability and adaptability of the
Bulgarian lavender (Lavandula angustifolia Mill.) sorts yield. Ag-
ricultural Science and Technology, 2 (3): 121–123.
Tholl, D., 2 006. Terpene synthases and the regulation, diversity and
biological roles of terpene metabolism. Current Opinion in Plant
Biology, 9 (3): 297–304.
Topalov, V., 1962. On the diversity of lavender population. Agricul-
tural Science, 6:,623–630 (Bg).
Topalov, V., 1969. Newly developed lavender cultivar Venetsh. Scien-
tifi c works of the High Agricultural Institute, V Kolarov, Plovdiv,
18 (1): 47–50 (Bg).
Zagorcheva, T., S. Stanev, K. Rusanov and I. Atanassov, 2013.
Comparative GC/MS analysis of lavender (Lavandula angustifo-
lia Mill.) infl orescence and essential oil volatiles. Agricultural Sci-
ence and Technology, 5 (4): 459–462.
Zheljazkov, V., C. Cantrell, T. Astatkie and E. Jeliazkova, 2013.
Distillation time effect on lavender essential oil yield and composi-
tion. Journal of Oleo Science, 62 (4): 195–199.
Received June, 1, 2016; accepted for printing June, 17, 2016
... Lavender essential oil has various biological activities and is used in a wide range of products and applications including aromatherapy, cosmetics, food and medicinal products [4][5][6][7][8]. The quality of lavender oil largely depends on the composition and relative content of terpenes and terpenoids, some of which are a subject of national and international quality standards, e.g. the ISO 3515:2002 standard [8,9]. The monoterpene esters such as linalyl acetate, lavandulyl acetate, geranyl acetate and others have been considered to largely contribute to the characteristic aroma and flavor as well to the biological activities of lavender oil [1,8,10]. ...
... Since 2014, Bulgaria has been the world largest supplier of lavender oil [2,5,16]. Lavender oil production in the country is based on the industrial cultivation of a small number of superior lavender varieties, all of them having high content of linalool and linalyl acetate and higher relative content of linalyl acetate compared to linalool [9]. Despite the importance of the linalool-to-linalyl-acetate (L/LA) ratio for the quality of the produced lavender oil, the genetic background controlling the L/LA ratio in the cultivated lavender varieties has not been well studied and no molecular markers suitable for marker assisted selection for this trait are currently available. ...
... The segregating population was derived from a self-pollinated plant of the industrially cultivated L. angustifolia var. Hemus, which is one of the most widely cultivated Bulgarian lavender varieties [9]. The population was previously genotyped using 289 SSR and SRAP markers resulting in the construction of a genetic linkage map consisting of 24 linkage groups/LG/, spanning a total of 219,352 cM, as described in details in Vassileva et al. [17]. ...
Article
Full-text available
The content of linalyl acetate and the ratio of linalool to linalyl acetate (L/LA ratio) are one of the important parameters that determine the quality of lavender oil. The characterization of a segregating population derived from a self-pollinated Lavandula angustifolia var. Hemus resulted in the identification of a single quantitative trait locus controlling the L/LA ratio (L/LA-QTL) and located on chromosome 8 of the lavender reference genome. The L/LA data analysis demonstrated that plants homozygous for one of the L/LA-QTL alleles had significantly higher linalool content, lower linalyl acetate content and higher L/LA ratio, than the plants which were either heterozygous or homozygous for the other allele. No significant difference was observed for the sum of linalool and linalyl acetate content among these three groups of plants, suggesting that the identified L/LA-QTL is related to an enzyme conversion of linalool to linalyl acetate. The BLAST search revealed that the L/LA-QTL region included a sequence of the LiAAT4 gene of monoterpene acetyltransferase, considered as a candidate gene for the L/LA-QTL locus. Sequence analysis of the LiAAT4 gene of var. Hemus revealed the presence of two alleles differing in two nucleotides and predicted amino acid substitutions. The comparison of the allele configurations of SSR, SRAP and LiAAT4 loci and the L/LA ratio of plants showing recombination in the L/LA-QTL region provided further support that LiAAT4 is a candidate gene underlying the identified L/LA-QTL and controlling the L/LA ratio. The application of molecular markers for the identified L/LA-QTL is discussed.
... Lavandula angustifolia Mill., lavender, is an aromatic plant in the Lamiaceae (mint) family [1]. While this plant is native to the Mediterranean region, it is cultivated throughout the world, with France and Bulgaria being two of the largest producers [2][3][4]. Lavender is an important economic plant and crop, prized for its essential oil, and is used extensively in cosmetics, flavors, fragrances, and medicines [5]. ...
... Of the bees observed in this study, A. mellifera, B. fervidus, and B. huntii comprised most of the observed bees visiting lavender, over 96%. The exact breakdown is as follows (exact count, rounded %): Apis mellifera (355, 88.3%), Bombus fervidus (17,4 ...
Article
Full-text available
Lavandula angustifolia Mill., lavender, is an aromatic plant in the Lamiaceae family. Lavender is an important economic plant that is cultivated throughout the world. Previous studies have shown that the primary pollinators of lavender in Europe and North Africa are bee species, specifically Bombus spp. However, similar studies have not been previously performed in North America. The current study, on cultivated population lavender (grown from seed) in Utah (USA), found a diverse community of bees visiting lavender over a 4-week sequential and successive blooming period. The observed and identified bees were distinguished across 8 genera and 12 species, of which 3 were species not native to North America. The most observed bees were Apis mellifera (88.3%), Bombus fervidus (4.2%), and B. huntii (3.7%). To investigate seed production and viability, lavender plants were either caged off and their access withheld from pollinators, or selectively granted access to various pollinators, to determine (1) if lavender is capable of self-pollination, (2) if pollination increases both the seed production rates and seed viability of lavender, and (3) which bee species are the most efficient pollinators of lavender. The findings from this study demonstrate the ecological interactions between pollinators both native and non-native to North America on lavender, a plant native to the Mediterranean region.
... (lavender), Lavandula intermedia Emeric ex Loisel. (lavandin) and Lavandula latifolia L. (spike) [3,4]. Lavandula angustifolia Mill. ...
... A little later, the varieties "Hemus", "Sevtopolis", "Druzhba" and "Yubileyna" were developed, which today are among the most common in our country. In recent decades, due to the enhanced interest in lavender production, cultivation areas in various regions of the country have increased, and today, Bulgaria has become a world leader with a production of 400 tons per year [2,3]. ...
Article
Full-text available
Increasing prices and market demand for organic products are stimulants of organic farming. However, this sector is a challenge for producers and further improvements are still necessary. The present study case was conducted to compare the effects of organic (OF) and conventional (CF) farming on lavender (Lavandula angustifolia Mill.) oil yield, plant pigments and essential oil composition. The study was conducted for two years in the period 2019–2020. Six private farms were included in the experiment with conventional and organic agriculture systems. They are located in Kazanlak Valley, Southern Bulgaria. Organic lavender inflorescences were determined to have chlorophyll a and total chlorophyll within a narrow range between 251.3 and 275.7 μg·g−1 and between 375.5 and 487.0 μg·g−1 compared to conventional ones—between 245.9 and 377.5 μg·g−1 and 385.3 and 595.4 μg·g−1 respectively. However, carotenoids and anthocyanins were in a wide range in organic lavender between 36.9 and 72.2 μg·g−1 and 410 and 1240 µg cyn-3-gly.g−1 compared to conventional ones—between 55.5 and 77.3 μg·g−1 and 200 and 780 µg cyn-3-gly.g−1, respectively, for both studied years. The key constituents in essential oil were linalyl acetate (28.42–38.23%), linalool (20.01–31.04%) and β-caryophyllene (7.95–14.97%). The composition was compared with the parameters set out in the international standard for lavender oil. The influence of the type of agricultural system on essential oil yield and its composition was not found. According to the obtained results, levels of chlorophyll a, chlorophyll b and total chlorophyll were higher in conventional farming than in organic farming for the second year of the study.
... Lavender is cultivated worldwide in a number of countries, and the leading lavender oil producers are Bulgaria, France, the UK, China, India, Spain, and others (Giray 2018). During the last few years, the volumes of lavender oil produced in Bulgaria steadily exceeded those of France, and the country became the world's top lavender oil producer (Giray 2018;Stanev et al. 2016;Zagorcheva et al. 2020), growing over 11145 ha of different lavender cultivars (varieties) and 50126 tons of lavender yield in 2022 (Anonymous, 2022). The high genetic diversity of the various cultivars as well as the high variety of ecological specifics in the regions of cultivation suggest a notable diversity in the composition of lavender essential oils (Giray 2018; Zagorcheva et al. 2013Zagorcheva et al. , 2020. ...
Article
Full-text available
Lavender essential oil is an economically important ingredient in perfumery, the food industry, and pharmacy. There is notable diversity in the composition of lavender essential oils. The reasons are the high genetic diversity of lavender cultivars and the variety of ecological specifics in the regions of cultivation. The aim of this research is to check which lavender essential oil variety is best regarding the content of the most important components through comparative statistical tests. We created a data set of 88 lavender essential oil samples from 16 countries. The multivariate statistics (hierarchical and non-hierarchical clustering) and factor analysis reveal hidden relationships between the objects of the study (samples) or between the variables characterizing the objects (chemical descriptors–16 components). The results are discussed in detail. All samples from Bulgaria, together with a few of the Italian, French, Greek, Indian, and Chinese samples, fall into one cluster with the standard maximums. Graphical abstract:
... It was found that valerenic acid allosterically modulated GABA A receptors in the central nervous system and induced an anxiolytic activity [24,25]. The variable chemical composition is a characteristic feature of plant raw materials, depending on many factors, including soil, climate, development stage, method and time of extraction, or genetic factors, which determine the existence of various chemotypes within one plant species [26][27][28]. For comparison, the results of the research carried out by Hassan et al. [29] showed that the content of valerenic acid in different species and morphological parts of Valeriana L. was in the range of 40-70 (mg/100 g d.m.) and acetoxyvalerenic acid was in the range of 20-210 (mg/100 g d.m.). ...
Article
Full-text available
Plant raw materials with a calming effect on the nervous system are increasingly used in modern phytotherapy. Lavender belongs to this group of plants, due to the content of essential oil with known therapeutic properties and other phytoconstituents that can be responsible for the sedative effect. Our studies confirmed the presence of sesquiterpenic acids characterized by sedative activity in lavender extracts. The contents of valerenic acid and acetoxyvalerenic acids in flowers and leafy stalks of two various Lavandula angustifolia cultivars—‘Blue River’ and ‘Ellagance Purple’—were determined. Analyses of methanolic extracts performed using the HPLC method showed that content of these sesquiterpenic acids varied with the cultivars and the morphological parts of the plant. The amount of acetoxyvalerenic acid was significantly higher than the amount of valerenic acid. In the ‘Blue River’ cultivar, higher levels of both compounds characterized by sedative properties were found. The content of valerenic acid in flowers ranged from 0.50 mg/100 g d.m. in the ‘Ellagance Purple’ cultivar to 1.75 mg/100 g d.m. in the ‘Blue River’ cultivar. In turn, leafy stalks contained 0.81 mg/100 g d.m. of valerenic acid in the ‘Ellagance Purple’ cultivar and 1.16 mg/100 g d.m. in the ‘Blue River’ cultivar. Interestingly, the ‘Blue River’ cultivar contained about 10 times more acetoxyvalerenic acid (65.80 mg/100 g d.m.) in flowers and four times more acetoxyvalerenic acid in leafy stalks (50.1 mg/100 g d.m.), in comparison with the ‘Ellagance Purple’ cultivar. The higher content of valerenic and acetoxyvalerenic acids in the flowers and leafy stalks of the ‘Blue River’ lavender cultivar can be important for its possible medical applications.
... Additionally, these oils are toxic and can be used to control storage pests (Manzoomi et al. 2010). It is commonly grown in southern Europe, particularly France, which produces almost 90% of the world's supply, and North Africa (Stanev et al. 2016). Although not widely known in Ethiopia, it has been commercially cultivated for a few years in the central rift valley of the country, particularly in the Koka area, for export purposes. ...
Article
Full-text available
Plants grown without soil are believed to be less affected by soilborne diseases. However, in a commercial greenhouse in Ethiopia's Rift valley, Lavender plants grown in hydroponic showed signs of severe stunting and galled roots. To identify the cause of the problem, root samples were taken. From these samples, single egg masses were obtained and used as inoculum for tomato cv. Moneymaker seedlings. The resulting seedlings were grown to produce a pure culture. DNA was extracted from second-stage juveniles (J2) from sixteen isolates derived from pure cultures and amplified the 28S rRNA and NADH dehydrogenase subunit 5 (Nad5) region of the mtDNA. The 28S rRNA and Nad5 were sequenced for two and five randomly selected isolates. A BLAST search of 28S rRNA sequences at NCBI showed a 98.34% sequence homology with known sequences of Meloidogyne javanica isolates. Moreover, Nad5 gene analysis, female perennial pattern, and the phylogenetic trees further confirmed the correct identification of this species. This is the first report of a nematode infecting plants growing in a hydroponic greenhouse in Ethiopia. Therefore, isolating any potential contaminants of the potting media for future lavender production are important.
Chapter
Lavandula angustifolia is a widespread blooming plant throughout Europe and the Mediterranean. Lavender offers various advantages for human health and has a long history of usage in conventional medicine to treat insomnia, and anxiety, and to enhance the quality of sleep. Lavender is frequently found in soaps, fragrances, bath salts, and scented sachets. Even in low quantities, it can add flavor to foods or drinks. Its effectiveness in treating a variety of ailments has been shown in various ethnopharmacological investigations. It contains anti-inflammatory, antioxidant, antispasmodic, sedative, insecticidal, antibacterial, and antifungal properties. Numerous research studies have explored the phytochemistry and pharmacological applications of Lavender. This species has high genetic diversity at morphological, molecular, and biochemical levels worldwide. DNA markers such as RAPD, ISSR, SSR, SNP, and SRAP were used to assess genetic diversity in L. angustifolia. However, it is still lacking in organized germplasm resources, improved cultivars, and suitable agrotechnologies, particularly for the Himalayan region. This chapter summarizes previous studies on taxonomy, geographical distribution, essential oil constituents, ethnopharmacological applications, genetic diversity, breeding strategies, and potential in this plant.
Article
Lavender (Lavandula spp.) is one of the most widely grown essential oil crops in the world. This study aimed to determine the nuclear DNA contents using flow cytometry, pollen viability using TTC (2,3,5-Triphenyl Tetrazolium Chloride) and IKI (Iodine Potassium Iodide) tests, pollen production quantities using hemacytometric method, and seed retention rates per spike and flower of lavender (L. angustifolia var. Raya) and lavandin (L. intermedia var. Super) grown under ecological conditions in Isparta province of Turkey. The nuclear DNA contents were 2.11 and 2.54 pg 2C-1, respectively in the lavender and lavandin cultivar. The flowers of the lavender cultivar produced abundant pollen grains (average 5800 pollen per flower and 1450 pollen per anther) with high viability (60.65-65.05%) and seed retention rate per spike (91.57% on average). The lavandin cultivar, which had very low pollen viability (1.08-3.32%) and pollen grains (average of 2350 pollen per flower and 587.5 pollen per anther) gave very low seed retention rates per spike (0.60% on average). While each flower had four ovaries with the potential to produce four nutlets, lavandin flowers produced only trace numbers (0.15% on average) of seeds. As a result, the lavandin cultivar had more nuclear DNA content, longer stem and spike, smaller size but more numerous flowers, less and lighter anthers, lower pollen grains and viability, and vey few inviabile seeds compared to the lavender cultivar. It has been observed by eye that honey bees do not visit lavender and lavandin flowers for collecting pollen, but solely for collecting nectar.
Article
Full-text available
In vitro studies of the antimicrobial activity of lavender essential oil from Lavandula angustifolia Mill. produced in Bulgaria in 2021 and 2022 by Bioagro Bg Ltd were carried out by determining the minimum bactericidal concentrations (MBC) and minimum fungicidal concentrations (MFC). Sixteen microbial strains of Esherihia coli, Salmonella enterica, Staphylococcus aureus, and Candida albicans were used, respectively, by 1 reference (ATCC) and 3 clinical isolates of each species. A very high antimicrobial activity of the essential oil from both batches was found. MBC and, respectively, MFC for all strains studied were below 0.1125 % (v/v) or 1.009 mg.mL-1.
Article
The harvesting technology of China's lavender industry is in urgent need of improvement, and there is a pressing demand to expedite the development of mechanized collection equipment to facilitate the modernization process and optimize efficiency within the sector. This article adopts a literature review method to introduce the current research status of lavender harvesting techniques, including mechanical properties, harvesting time, and distribution of essential oils in stems and leaves, both domestically and internationally. It is found that there is relatively little research on lavender harvesting techniques in China, and the main research hotspots are focused on industrial development and essential oil extraction. By summarizing the mechanical harvesting equipment and its characteristics of lavender both domestically and internationally, it is analyzed that developed countries have fully achieved mechanical harvesting of lavender, while China's level of mechanical harvesting of lavender lags far behind developed countries. It is proposed to develop diversified lavender harvesting equipment, strengthen the research and cooperation of lavender harvesting machinery, promote the integration of agricultural machinery and agronomy, and combine basic research with equipment development. These development measures have a certain reference and promotion effect on accelerating the process of mechanical harvesting of lavender in China.
Article
Full-text available
The research was carried out during the 2009 and 2010 growing period with the aim of determining agricultural and technological characteristics of lavender cultivars. When the agricultural characteristics of the lavender and lavandin cultivars were examined, in both years the highest fresh stem flower yield was obtained from Dutch (5467 and 8204 kg ha(-1), respectively) and the highest dry stemless flower yield from Super A (1083 and 1463 kg ha(-1)., respectively) cultivars. The highest essential oil content in both fresh stem flowers (the first year 2.00 %, the second year 1.90 %) and dry stemless flowers (the first year 9.62 %, the second year 8.87 %) was determined from Silver. Linalool, linalyl acetate and camphor were determined as the main components of essential oil in the lavender cultivar. The highest linalool content in fresh stem flowers was determined to be from Dutch (43.3 %) in the first year and from Vera (43.9 %) in the second year. The highest linalyl acetate content from Super A (42.5 and 19.8 %, respectively) and camphor content from Super A (19.8 %) in the first year and Dutch (10.0 %) in the second year were determined. The highest linalool content in dry stemless flowers from Dutch (46.5 and 47.0 %, respectively), linalyl acetate content from Super A (32.8 and 29.5 %, respectively) in both years and camphor content from Silver (12.6 %) in the first year and Dutch (10.9 A) in the second year were obtained.
Article
Full-text available
The Lavandula genus, which includes lavender (Lavandula angustifolia) and lavandin (L. angustifolia × Lavandula latifolia), is cultivated worldwide for its essential oils, which find applications in perfumes, cosmetics, food processing and, more recently, in aromatherapy products. The chemical composition of lavender and lavandin essential oils, usually produced by steam distillation from the flowering stems, is characterized by the presence of terpenes (e.g. linalool and linalyl acetate) and terpenoids (e.g. 1,8-cineole), which are mainly responsible for their characteristic flavour and their biological and therapeutic properties. Lavender and lavandin distilled straws, the by-products of oil extraction, were traditionally used for soil replenishment or converted to a fuel source. They are mineral- and carbon-rich plant residues and, therefore, a cheap, readily available source of valuable substances of industrial interest, especially aroma and antioxidants (e.g. terpenoids, lactones and phenolic compounds including coumarin, herniarin, α-bisabolol, rosmarinic and chlorogenic acids). Accordingly, recent studies have emphasized the possible uses of lavender and lavandin straws in fermentative or enzymatic processes involving various microorganisms, especially filamentous fungi, for the production of antimicrobials, antioxidants and other bioproducts with pharmaceutical and cosmetic activities, opening up new challenging perspectives in white biotechnology applications.
Article
Full-text available
Main conclusion: We identified and characterized EST-SSRs with strong discrimination power against Lavandula angustifolia and Lavandula x intermedia . The markers also showed considerable cross-species transferability rate into six related Lavandula species. Lavenders (Lavandula) are important economical crops grown around the globe for essential oil production. In an attempt to develop genetic markers for these plants, we analyzed over 13,000 unigenes developed from L. angustifolia and L. x intermedia EST databases, and identified 3,459 simple sequence repeats (SSR), which were dominated by trinucleotides (41.2 %) and dinucleotides (31.45 %). Approximately, 19 % of the unigenes contained at least one SSR marker, over 60 % of which were localized in the UTRs. Only 252 EST-SSRs were 18 bp or longer from which 31 loci were validated, and 24 amplified discrete fragments with 85 % polymorphism in L. x intermedia and L. angustifolia. The average number of alleles in L. x intermedia and L. angustifolia were 3.42 and 3.71 per marker with average PIC values of 0.47 and 0.52, respectively. These values suggest a moderate to strong level of informativeness for the markers, with some loci producing unique fingerprints. The cross-species transferability rate of the markers ranges 50-100 % across eight species. The utility of these markers was assessed in eight Lavandula species and 15 L. angustifolia and L. x intermedia cultivars, and the dendrogram deduced from their similarity indexes successfully delineated the species into their respective sections and the cultivars into their respective species. These markers have potential for application in fingerprinting, diversity studies and marker-assisted breeding of Lavandula.
Article
Main conclusion: Two alcohol acetyltransferases, LiAAT-3 and LiAAT-4, from L. x intermedia were cloned, expressed in bacteria, and functionally characterized. Two monoterpene acetyltransferase cDNA clones (LiAAT-3 and LiAAT-4) were isolated from L. x intermedia glandular trichomes, expressed in bacteria to produce, and functionally characterize the encoded proteins in vitro. The recombinant LiAAT-3 and LiAAT-4 proteins had molecular weights of ca. 47 and 49 kDa, respectively, as evidenced by SDS-PAGE. The K m (mM) values for the recombinant LiAAT-3 and LiAAT-4 were 1.046 and 0.354 for lavandulol, 1.31 and 0.279 for geraniol, and 0.87 and 0.113 for nerol, respectively. The V max (pkat/mg) values for LiAAT-3 and LiAAT-4 were 92.13 and 105.1 for lavandulol, 81.07 and 52.17 for geraniol, and 15.02 and 15.8 for nerol, correspondingly. Catalytic efficiencies (mM(-1) min(-1)) for LiAAT-3 and LiAAT-4 were 0.27 and 0.85 for lavandulol, 0.19 and 0.54 for geraniol, and 0.052 and 0.4 for nerol, respectively. These kinetic properties are in the range of those reported for other plant acetyltransferases, and indicate that LiAAT-4 has a better catalytic efficiency than LiAAT-3, with lavandulol serving as the preferred substrate for both enzymes. Transcripts for both genes were abundant in L. angustifolia and L. x intermedia flowers, where monoterpene acetates are produced, and were undetectable (or present in trace quantities) in L. latifolia flowers, which do not accumulate significant amounts of these metabolites.
Article
Lavandula pedunculata (Mill.) Cav. subsp. lusitanica, L. stoechas L. subsp. stoechas and L. viridis l'Hér. are three lavender taxa that belong to the botanical section Stoechas and are widely used as aromatherapy, culinary herb or folk medicine in many Mediterranean regions. The analysis of their bioactive volatile constituents revealed the presence of 124 substances, the most abundant being the bicyclic monoterpenes fenchone, camphor and 1,8-cineole that give these three species their respective chemotypes. Most noteworthy was fenchone which, with its reduced form fenchol, made 48% of the total volatile constituents of L. pedunculata whilst present at 2.9% in L. stoechas and undetectable in L. viridis. In order to provide a molecular explanation to the differences in volatile compounds of these 3 species, two monoterpene synthases (monoTPS) and one sesquiterpene synthase (sesquiTPS) were cloned in L. pedunculata and functionally characterized as fenchol synthase (LpFENS), α-pinene synthase (LpPINS) and germacrene A synthase (LpGEAS). The two other lavender species contained a single orthologous gene for each of these three classes of TPS with similar enzyme product specificities. Expression profiles of FENS and PINS genes matched the accumulation profile of the enzyme products unlike GEAS. This study provides one of the rare documented cases of chemotype modification during plant speciation via changes in the level of plant TPS gene expression, and not functionality.
Article
In this paper we characterize three sTPSs: a germacrene D (LaGERDS), a (E)-β-caryophyllene (LaCARS) and a τ-cadinol synthase (LaCADS). τ-cadinol synthase is reported here for the first time and its activity was studied in several biological models including transiently or stably transformed tobacco species. Three dimensional structure models of LaCADS and Ocimum basilicum γ-cadinene synthase were built by homology modeling using the template structure of Gossypium arboreum δ-cadinene synthase. The depiction of their active site organization provides evidence of the global influence of the enzymes on the formation of τ-cadinol: instead of a unique amino-acid, the electrostatic properties and solvent accessibility of the whole active site in LaCADS may explain the stabilization of the cadinyl cation intermediate. Quantitative PCR performed from leaves and inflorescences showed two patterns of expression. LaGERDS and LaCARS were mainly expressed during early stages of flower development and, at these stages, transcript levels paralleled the accumulation of the corresponding terpene products (germacrene D and (E)-β-caryophyllene). By contrast, the expression level of LaCADS was constant in leaves and flowers. Phylogenetic analysis provided informative results on potential duplication process leading to sTPS diversification in lavender.