Effects of foliar application of micronutrients (Fe and Zn) on flower yield and essential oil of chamomile (Matricaria chamomilla L.)
ABSTRACT In order to evaluate the effects of foliar application of micronutrients (iron and zinc) on yield and essential oil of chamomile, two field experiments were carried out in 2008 and 2009 at the Research Station of Faculty of Agriculture, University of Tabriz, Iran. Both experiments were arranged as factorial on the basis of randomized complete block design (RCBD) with four replications. Treatments were foliar application of micronutrients (Fe, Zn and Fe + Zn through ferrous sulphate and zinc sulphate at the concentration of 0.35%) and time of application (at stem elongation, flowering and both stages) with control (without foliar application). The results showed that flower yield, essential oil percentage, and essential oil yield increased by foliar application of Fe and Zn compared with control (untreated). The highest flower yield (1963.0 kgha -1), essential oil percentage (1.062%), and essential oil yield (20.835 kgha -1) were obtained for Fe + Zn spray treatment with about 46.4, 24.64, and 81.77% improvements in comparison with control, respectively. The time of foliar application had significant effect on flower dry yield, essential oil percentage and essential oil yield. The foliar application at both stages of stem elongation and flowering had more beneficial effects on these characters as compared with spray at only one stage. It seems that foliar application of iron and zinc can considerably improve flower yield and essential oil content of chamomile especially in calcareous soils.
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ABSTRACT: Arid regions in Egypt are characterized by poor nutrients such as macro and microelements and unfavorable environmental conditions which negatively affect growth and productivity of medicinal and aromatic plants including anise (Pimpinella anisum L.), coriander (Coriandrum sativum L.) and sweet fennel (Foeniculum vulgare var. Dolce) plants. Thus, the main objective of the present investigation was to study the effect of different levels of NP fertilizers, trace elements and their interactions on the morphological and biochemical contents of these three plants under arid regions conditions. The effects of NP and trace elements on the growth (height, leaf number, branch number, umbel number, fresh weight, dry weight and fruit yield per plant) was measured and quantitative analysis of essential oils, fixed oil, total carbohydrates, soluble sugars and nutrient content of anise, coriander and sweet fennel were performed. The most effective rate was N3P3 x trace elements interaction, resulting in a positive increase in vegetative growth characters. The highest values of vegetative growth characters were 53.4, 45.9, 10.3, 33.5, 36.8, 11.8 and 7.9, respectively for anise; 83.0, 69.3, 9.8, 29.0, 34.0, 17.5 and 14.4, respectively for coriander; 89.8, 32.6, 7.8, 22.9, 257.8, 99.1 and 27.8, respectively for sweet fennel. As well as N3P3 x trace elements led to higher biochemical contents than the control. The increases were 0.9, 0.3 and 0.9% in essential oil; 5.4, 4.4 and 3.7% in fixed oil, 9, 7.9 and 8.2% in total carbohydrates; 2.4, 2.8 and 1.6% in soluble sugars; 5.0, 7.5 and 14.4% in crude protein; 0.8, 2.0 and 2.3% in nitrogen; 1.5, 0.6 and 0.4% in phosphorous; 1.3, 1.2 and 1.7% in potassium for anise, coriander and sweet fennel, respectively.Journal of soil science and plant nutrition. 09/2012; 12(3):581-596.
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ABSTRACT: The sweet herb of Paraguay, Stevia rebaudiana (Bertoni), is becoming more important worldwide in herbal care for diabetes, as it produces the zero-calorie sweeteners steviol glycosides (SGs)—stevioside and rebaudioside-A. While arbuscular mycorrhizal fungi (AMF) have been shown to enhance production of secondary metabolites in many plant species, their effect on S. rebaudiana has not been studied. Moreover, relatively little is known about the mechanisms that may be involved in the increased accumulation of phytochemicals in mycorrhizal plants. Therefore, this study was performed to test the ability of Rhizophagus fasciculatus (Thaxt.) C. Walker & A. Schüßler to improve the yield of SGs in S. rebaudiana and to relate this with some AMF-induced physiological changes in addition to improved phosphorus (P) uptake. The performance of plants inoculated with R. fasciculatus was compared with that of non-mycorrhizal plants with similar P concentrations. Mycorrhizal (M) and non-mycorrhizal plants with P-supplementation (NM + P) produced higher concentrations of SGs compared with control plants. However, M plants had more SGs than did NM + P plants. The higher content of SGs in M plants is due to increased concentrations of SGs and to the enhanced biomass of the shoots. The increase in biomass is directly due to the improved uptake of nutrients (N, K, Mg, Cu, Fe, Mn and Zn), and chlorophyll and carbohydrate concentrations in M plants. Higher concentrations of total carbohydrates and jasmonic acid in M plants than in NM + P plants contribute to more biosynthesis of SGs via the methyl erythritol phosphate pathway. This study suggests that AMF-mediated increases in SGs involve both nutritionally and non-nutritionally linked mechanismsApplied Soil Ecology 01/2013; 72:187-194. · 2.21 Impact Factor
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ABSTRACT: The adequate growth of plants can be achieved only by a balanced ratio of biologically active nutrients in soil along with its readily availability. Linseed seems to be an advantageous secondary oilseed crop widely used in industrial purposes, which can serve additional purpose of phytoextraction of heavily infested soils with heavy metals. In this study, we have made an effort to find out the optimum dose of heavy metals necessary as micronutrients like copper (Cu), iron (Fe) and zinc (Zn) for the enhancement of linseed yield along with the distribution of heavy metals in different plant parts. Quantitative enhancement in different traits of linseed plant due to Cu, Fe and Zn fertilization especially for capsules per plant after maturity suggested positive association between heavy metal supply and morphological traits, which indirectly enhanced seed yield. There was a positive correlation between Zn supply and seed yield. In the treatments with Cu and Fe fertilization, seed yield was positively correlated to plant height, capsules per plant and seeds per five capsules. According to this study, it is concluded that linseed has the ability to accumulate majorly Fe followed by Cu and Zn.Archives of Agronomy and Soil Science 02/2014; 60(10).
Journal of Medicinal Plants Research Vol. 4(17), pp. 1733-1737, 4 September, 2010
Available online at http://www.academicjournals.org/JMPR
ISSN 1996-0875 ©2010 Academic Journals
Full Length Research Paper
Effects of foliar application of micronutrients (Fe and
Zn) on flower yield and essential oil of chamomile
(Matricaria chamomilla L.)
Yousef Nasiri1*, Saeid Zehtab-Salmasi1, Safar Nasrullahzadeh1, Nosratollah Najafi2 and
1Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
2Department of Soil Science, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
Accepted 14 July, 2010
In order to evaluate the effects of foliar application of micronutrients (iron and zinc) on yield and
essential oil of chamomile, two field experiments were carried out in 2008 and 2009 at the Research
Station of Faculty of Agriculture, University of Tabriz, Iran. Both experiments were arranged as
factorial on the basis of randomized complete block design (RCBD) with four replications. Treatments
were foliar application of micronutrients (Fe, Zn and Fe + Zn through ferrous sulphate and zinc
sulphate at the concentration of 0.35%) and time of application (at stem elongation, flowering and
both stages) with control (without foliar application). The results showed that flower yield, essential
oil percentage, and essential oil yield increased by foliar application of Fe and Zn compared with
control (untreated). The highest flower yield (1963.0 kgha-1), essential oil percentage (1.062%), and
essential oil yield (20.835 kgha-1) were obtained for Fe + Zn spray treatment with about 46.4, 24.64, and
81.77% improvements in comparison with control, respectively. The time of foliar application had
significant effect on flower dry yield, essential oil percentage and essential oil yield. The foliar
application at both stages of stem elongation and flowering had more beneficial effects on these
characters as compared with spray at only one stage. It seems that foliar application of iron and zinc
can considerably improve flower yield and essential oil content of chamomile especially in calcareous
Key words: Chamomile, essential oil, foliar application, iron, yield, zinc.
During the recent decades, medicinal plants gained a
substantial importance in agricultural production,
pharmacy and exportation because of their use as a
raw material for the pharmaceutical industry (Abou-Arab
and Abou, 2000). Chamomile [Matricaria chamomilla L.,
syn.Chamomilla recutita L.] (Asteraceae) belongs to a
major group of cultivated medicinal plants. Chamomile
anthodia (Matricariae flos
therapeutically, mainly due to their anti-inflammatory
and spasmolytic effects (Schilcher, 1987). It is an important
*Corresponding author. E-mail: email@example.com.
Abbreviations: RCBD, Randomized complete block design;
Cu, copper; Zn, zinc; Fe, iron; Mn, Manganese.
drug) are used
medicinal and aromatic plant of both traditional and
modern systems of medicine. The blue essential oil of
flowers of this plant has a wide application in medicine,
cosmetics, and foodstuffs, in the flavouring of alcoholic
and non-alcoholic beverages (Sashidhara et al., 2005).
A balanced fertilization program with macro and
micronutrients in plant nutrition is very important in the
production of high yield with high quality products
(Sawan et al., 2001). For adequate plant growth and
production, micronutrients are needed in small
quantities; however, their deficiencies cause a great
disturbance in the physiological and metabolic pro-
cesses in the plant (Bacha et al., 1997). Plants normally
take up nutrients from soils through their roots although
nutrients can be supplied to plants as fertilizers by foliar
sprays. Foliar feeding is a relatively new and
controversial technique of feeding plants by applying
1734 J. Med. Plant. Res.
Table 1. Monthly temperature and precipitation during the growing season in 2008 and 2009.
Average temperature (°C)
Month 2008 2009 2008 2009
May 6.7 7.7 22.6 23.7
June 12.6 11.6 28.7 27.3
July 16.3 15.9 32.5 31.1
August 16.7 15.5 33.7 37.9
liquid fertilizer directly to their leaves (Bernal et al.,
2007; Baloch et al., 2008). Throughout the world
microelements as Fe, Zn, Mn and Cu are added to foliar
fertilizers, in order to compensate their deficiency
especially in arid and semi arid regions (Kaya et al.,
2005). Micronutrients, especially Fe and Zn, act either
as metal components of various enzymes or as
functional, structural, or regulatory cofactors. Thus, they
are associated with saccharide metabolism, photo-
synthesis, and protein synthesis (Marschner, 1995).
Iron is mainly present in the form of insoluble Fe (III),
therefore, unavailable to higher plants, particularly in
neutral and alkaline soils (Shao et al., 2007).
Essential oil of Mentha piperita increased by 28.2%
by foliar application of 3 ppm zinc chloride foliar
application compared with the control (Akhtar et al.,
2009). Essential oil biosynthesis in basil (Ocimum
sanctum L.) is strongly influenced by Fe and Zn (Misra
et al., 2006). Misra and Sharma (1991) reported that
zinc application stimulated the fresh and dry matter
production, essential oil and menthol concentration of
Japanese mint. Foliar spraying with zinc (100 ppm) in
blue sage (Salvia farinacea L.) enhanced the length of
peduncle, length of main inflorescence, number of
inflorescence and florets, and fresh and dry weight of
inflorescences/ plant (Nahed and Balbaa, 2007).
Influence of microelements especially iron and zinc on
the yield and essential oil of chamomile plants is not
well documented. Therefore, the purpose of this
research is to investigate the effect of foliar application
of iron and zinc at different stages of growth on flower
yield and essential oil of M. chamomilla in a calcareous
MATERIALS AND METHODS
Two field experiments were carried out in 2008 and 2009 at the
Research Farm of the Faculty of Agriculture, University of Tabriz,
Tabriz (37º, 5´ N, 46º, 17´ E and 1360 m mean sea level), Iran.
The meteorological data recorded during the trial period both
years are shown in Table 1. The physicochemical properties of
soil and irrigation water characteristics are given in Table 2 (Page
et al., 1982). The treatments were foliar application (Fe, Zn and
Fe + Zn by using ferrous sulphate and zinc sulphate at the
concentration of 0.35% for the both micronutrients) and time of
foliar application (at stem elongation, flowering and both stages)
with control (without foliar application). These treatments were
arranged in a factorial experiment on the basis of randomized
complete block design with four replications.
Seeds of chamomile (M. chamomilla L.) obtained from Hungary
and planted on prepared plots in May 2008 and 2009. The plots
were 4 x 2 m with 6 rows, 0.30 m row distance and 0.10 m seed
distance. Required fertilizers except iron and zinc were added to
the plots according to soil test results (Table 2). Soil moisture was
kept at adequate levels to prevent water deficit and wilting. Weed
control was done by hand as required. Foliar spray was done
according to experimental treatments. Flowers were harvested
four times from three central rows (1 m2) in 7 - 10 days intervals.
Flowers were dried in a shady place and prepared for essential oil
extraction. 15 g dry flowers of chamomile were hydro-distilled in a
modified Clevenger apparatus in 1000 mL round bottomed flaks
with 500 mL distilled water for 4 h (Hoelz and Demuth, 1975;
Letchamo, 1993). Data were analyzed using MSTATC statistical
package. The least significant difference (LSD) at 5% level was
used to compare the means of treatments.
RESULTS AND DISCUSSION
Foliar application of iron, zinc and iron + zinc and time
of application had significant effects on flower yield,
essential oil percentage and essential oil yield (p<0.01).
Flower yield and percentage of essential oil were also
significantly affected by year (p<0.05). However, the
interactions of these treatments were not significant
(p≥0.05) for any of the parameters. The highest mean
flower yield was obtained by the foliar application of Fe
+ Zn, 46.4% improvement in comparison with the
control (Table 3). A similar effect of Zn supply on this
parameter was also reported on M. chamomilla
(Grejtovský et al., 2006), S. farinacea (Nahed and
Balbaa, 2007), Coriandrum sativum (Said-Al Ahl and
Omer, 2009) and Ocimum basilicum (Said-Al Ahl and
Mahmoud, 2010). Zinc is one of the eight essential
trace elements which is necessary for the normal
healthy growth and reproduction of crop plants (Parker
and Thomason, 1992).
The positive effects of Fe and Zn on plant may be
due to their effects as a metal component of some
enzymes or regulatory for the others. Moreover, they
have essential roles in plant metabolism (Abd El-Hady,
2007). Essential oil percentage of chamomile flowers
was significantly increased by foliar application of Fe +
Zn. It was improved by 10.16, 7.48 and 24.64% in
Nasiri et al. 1735
Table 2. Physico-chemical properties of the soil and irrigation water characteristics.
EC (dS m-1)
Organic carbon (%)
Total N (%)
Available P (mgkg−1)
Available K (mgkg−1)
Mn (mg kg−1)
Zn (mg kg−1)
Fe (mg kg−1)
Cu (mg kg−1)
Calcium Carbonate equivalent (gkg-1)
Mg2+ ( meqL−1)
Na+ ( meqL−1)
Cl− ( meqL−1)
- ( meqL−1)
-2 ( meqL−1)
Table 3. The influence of iron and zinc foliar application on flower yield, essential oil percentage and
essential oil yield of M. chamomilla L. (Means of the two years).
( kg .ha-1 )**
Iron + Zinc 1963.0
CV % 10.53
† Control: n = 8 and Other: n = 24. ** Significant at 1% levels.
Essential oil yield
† Control Versus Other 123.33
comparison with the foliar application of Fe, Zn and
control, respectively (Table 3). These results are in
agreement with those reported for Japanese mint
(Misra and Sharma, 1991), O. sanctum (Misra et al.,
2006), peppermint (Akhtar et al., 2009) and sweet basil
(Said-Al Ahl and Mahmoud, 2010). The highest
essential oil yield (20.835 kg.ha-1) was obtained by the
foliar application of Fe and Zn followed by separate
application of Fe and Zn. The difference in essential oil
yield between the latter treatments was not significant,
but essential oil yield of control was significantly lower
than that of other treatments (Table 3). Zehtab-Salmasi
et al. (2008) reported that essential oil yield of M.
piperita increased by the application of these
micronutrients. Said-Al Ahl and Mahmoud (2010) also
obtained the highest values of essential oil yield by
foliar spraying of a mixture of iron + zinc in sweet basil.
The highest flower yield (1894.6 kg.ha-1) was
observed in the plants that treated at both stages of
stem elongation and flowering. There was no significant
difference between foliar application at two stages of
stem elongation and flowering (Table 4). The essential
oil percentage for the foliar applications of Fe and Zn at
different stages of chamomile development (stem
elongation, flowering and both stages) was statistically
similar, but it was significantly higher than that for
control (Table 4). Foliar application of Fe and Zn at both
stages (stem elongation + flowering) led to the highest
production of essential oil yield, which was 67.68%
more than that of control. Foliar application of the
nutrients at the individual stages (stem elongation or
flowering) was also significantly improved the essential
oil yield of chamomile (Table 4).
Micronutrients, especially Fe and Zn act as metal
components of various enzymes and also are asso-
ciated with saccharide metabolism, photosynthesis, and
protein synthesis and Iron has important functions in
plant metabolism, such as activating catalase enzymes
associated with superoxide dismutase, as well as in
photorespiration, the glycolate pathway and chlorophyll
content. Zinc is an essential micronutrient for synthesis
of auxin, cell division and the maintenance of mem-
brane structure and function. Zinc deficiency reduces
plant growth, pollen viability, flowering, number of fruits
and seed production (Sharma et al., 1990; Marschner,
1995). Therefore, sufficient amount of these nutrients in
1736 J. Med. Plant. Res.
Table 4. The influence of time of foliar application (iron and zinc) on flower yield, essential oil
percentage and essential oil yield of M. chamomilla L. (Means of the two years).
( kg .ha-1 )**
Control (untreated) 1340.8
Stem elongation stage 1759.3
Flowering stage 1709.4
Both stages 1894.6
Control Versus Other 123.33
CV % 10.53
† Control: n = 8 and Other: n = 24. ** Significant at 1% levels.
Essential Oil Yield
Table 5. The influence of year (2008 & 2009) on flower yield, essential oil
percentage and essential oil yield of M. chamomilla L.
( kg .ha-1 )*
CV % 10.53
†n = 40, * significant at 5 % levels, ns non significant at 5% levels.
Essential oil yield
the plant is necessary for normal growth, in order to
obtain satisfactory yield. Although, foliar application of
various macro and micro nutrients has been proved
beneficial, foliar feeding is a relatively new and
controversial technique of feeding plants by applying
liquid fertilizer directly to their leaves (Baloch et al.,
2008; Yassen et al., 2010). Abd El- Wahab (2008)
reported that micronutrients such as iron, manganese
and zinc have important roles in plant growth and yield
of aromatic and medicinal plants. The foliar application
of mineral nutrients offers a method of supplying
nutrients to higher plants that are more efficiently than
methods involving root application when soil conditions
are not suitable for nutrients availability (Erdal et al.,
2004). Flower yield in the first year (2008) was greater
than that in the second year (2009). In contrast, the
highest essential oil percentage was obtained in the
second year. Consequently, essential oil yield per unit
area was statistically similar for both years (Table 5).
In general, it can be concluded that foliar application of
Fe and Zn can considerably improve the flower and
essential oil yields of chamomile, particularly if these
micronutrients were applied together at both stages of
stem elongation and flowering.
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