Abstract
Introduction: Iran’s climate is mostly arid and semi-arid, where water availability is a major problem. Water stress substantially alters plant metabolism, decreasing plant growth and photosynthesis and profoundly affecting ecosystems and agriculture, as well as human societies. Unfortunately, water deficiency is increasingly becoming a serious problem in agriculture in Iran whereas the national average annual precipitation is less than 249 mm. Recently, medicinal and aromatic plants have received much attention in several fields such as agroalimentary, perfumes, pharmaceutical industries and natural cosmetic products. Although, secondary metabolites in the medicinal and aromatic plants impressed conventionally by their genetic makeup; moreover their biosynthesis is strongly influenced by environmental factors. It means biotic and abiotic environmental factors affect growth parameter, essential oil yield and constituents. Abiotic environmental stresses like drought have the most effect on medicinal plants. In arid and semi-arid regions like south of Iran where water availability is a major limitation, using plants with low water consumption is one way to manage available water efficiently. Chamomile (Matricaria recutita L.) and chicory (Cichorium intybus) are annual plants belonging to Asteraceae family naturally widespread in west, northwest and south of Iran and their consumption has a long history in Iranian folklore medicine. Over 120 components have been identified in these plants essential oil, while, chamazulene, camphor, bisabolol oxides A and B, farnesene and ά- bisabolonoxide are the most important ones. Materials and Methods: This study was conducted in Research Farm of Islamic Azad University, Shoshtar Branch, Iran during 2010-2011 in order to evaluate the effects of water stress levels on growth, photosynthesis and essential oil yield of German chamomile (Matricaria recutita L.) and chicory (Cichorium intybus). Two water stress levels viz. medium at 75% field capacity (FC) (I 75) and sever at 55% FC (I 55) were included in the study, while 90% FC (I 90) was taken as control. The experiment was laid out based on a randomized complete block design (RCBD) with four replications. Net plot size was 2 m × 2 m having plants density of 120 chamomile m-2 and 100 chicory m-2. Sowing was done manually on well prepared seedbed in November 2010 and plants were harvested in June 2011. Irrigation treatments were started three weeks after seed sown when seedling started their growth and development. Chamomile and chicory essential oil percentage, essential oil yield, dry weight, photosynthesis and chlorophyll content were assayed in this research. Results and Discussion: Results showed that drought stress had significant effect on photosynthesis, chlorophyll a concentration, plant height and dry matter yield of chamomile and chicory. The Lowest flowers dry yield of chamomile and leaf dry weight of chicory obtained from severe drought stress level (47 and 195 gr m-2). The highest essential oil yield of chamomile (56.6 g m-2) and chicory (226.9 gr m-2) showed in mild drought stress treatment. Results indicated that medium drought stress increased seconds’ metabolites concentration and essential oil yield of chamomile and chicory. Important second compound in chamomile and chicory essential oil were camphor, α-pinene, β-pinene, ά-bisabolol and chamazulene. Drought stress decreased photosynthesis rate and minimum photosynthesis rate in chamomile and chicory were 9.0 mgl CO2 m-2 s-3 and 12.0 mgl CO2 m-2 s-3 under severe drought stress treatment. In chamomile the lowest chlorophyll a content showed in mild and severe drought stress treatments (1.1 and 1.2 mg g-1). Minimum chlorophyll a and b content of chicory obtained from severe drought stress treatment (0.7 and 1.02 mg g-1 respectively).Results of the study clearly elaborate that severe drought stress hampered the growth, photosynthetic rate and lowered the oil yield of chamomile, whereas medium drought stress (irrigation at 75% of FC level) improved the growth and oil productivity even more than well watered conditions. Although, severe water stress observed sizeable rise in essential oil contents but due to drastic reduction in flower or leaf dry weight, severe drought stress exhibited lowest oil yield in chamomile and chicory. Conclusion: The results of the study clearly elaborated that medium drought stress (irrigation at 75% of FC) enhanced the essential oil productivity, while severe water stress (55% FC) decreased chamomile and chicory growth, photosynthesis rate and essential oil yield. Moreover, under drought stress quantity of chamomile and chicory oil was improved. Therefore, chamomile and chicory should be irrigated at 75% FC level to attain higher essential oil yield.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by-sa. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 19
Claim · model-written summary
Severe drought gave the lowest chamomile flower dry yield, 47 gr m-2.
- Taxon
- chamomilee0
- Treatment
- severe drought stress levele0
- Outcome
- flowers dry yielde0
- Direction
- Loweste0
- Value
- 47 and 195 gr m-2e0
Not reportedComparator
Verbatim
e0“The Lowest flowers dry yield of chamomile and leaf dry weight of chicory obtained from severe drought stress level (47 and 195 gr m-2)”
Claim · model-written summary
Severe drought gave the lowest chicory leaf dry weight, 195 gr m-2.
- Taxon
- chicory
Cichorium intybuse0 - Treatment
- severe drought stress levele0
- Outcome
- leaf dry weighte0
- Direction
- Loweste0
- Value
- 47 and 195 gr m-2e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The Lowest flowers dry yield of chamomile and leaf dry weight of chicory obtained from severe drought stress level (47 and 195 gr m-2)”
Claim · model-written summary
Mild drought gave the highest chamomile essential oil yield, 56.6 g m-2.
- Taxon
- chamomilee0
- Treatment
- mild drought stress treatmente0
- Outcome
- essential oil yielde0
- Direction
- higheste0
- Value
- 56.6 g m-2e0
Not reportedComparator
Verbatim
e0“The highest essential oil yield of chamomile (56.6 g m-2) and chicory (226.9 gr m-2) showed in mild drought stress treatment”
Claim · model-written summary
Mild drought gave the highest chicory essential oil yield, 226.9 gr m-2.
- Taxon
- chicoryCichorium intybuse0
- Treatment
- mild drought stress treatmente0
- Outcome
- essential oil yielde0
- Direction
- higheste0
- Value
- 226.9 gr m-2e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The highest essential oil yield of chamomile (56.6 g m-2) and chicory (226.9 gr m-2) showed in mild drought stress treatment”
Claim · model-written summary
Medium drought increased chamomile secondary metabolite concentration.
- Taxon
- chamomilee0
- Treatment
- medium drought stresse0
- Outcome
- seconds’ metabolites concentratione0
- Direction
- increasede0
Not reportedComparator
Verbatim
e0“medium drought stress increased seconds’ metabolites concentration and essential oil yield of chamomile and chicory”
Claim · model-written summary
Medium drought increased chicory secondary metabolite concentration.
- Taxon
- chicoryCichorium intybuse0
- Treatment
- medium drought stresse0
- Outcome
- seconds’ metabolites concentratione0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“medium drought stress increased seconds’ metabolites concentration and essential oil yield of chamomile and chicory”
Claim · model-written summary
Camphor, α-pinene and β-pinene were important essential oil compounds in the studied plants.
Verbatim
e0“Important second compound in chamomile and chicory essential oil were camphor, α-pinene, β-pinene, ά-bisabolol and chamazulene”
Claim · model-written summary
Ά-bisabolol and chamazulene were important essential oil compounds in the studied plants.
- Taxon
- chicoryCichorium intybuse0
- Outcome
- ά-bisabolol and chamazulenee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Important second compound in chamomile and chicory essential oil were camphor, α-pinene, β-pinene, ά-bisabolol and chamazulene”
Claim · model-written summary
Severe drought reduced chamomile photosynthesis to a minimum of 9.0 mgl CO2 m-2 s-3.
- Taxon
- chamomilee0
- Treatment
- severe drought stress treatmente0
- Outcome
- photosynthesis ratee0
- Direction
- decreasede0
- Value
- 9.0 mgl CO2 m-2 s-3e0
Not reportedComparator
Verbatim
e0“Drought stress decreased photosynthesis rate and minimum photosynthesis rate in chamomile and chicory were 9.0 mgl CO2 m-2 s-3 and 12.0 mgl CO2 m-2 s-3 under severe drought stress treatment”
Claim · model-written summary
Severe drought reduced chicory photosynthesis to a minimum of 12.0 mgl CO2 m-2 s-3.
- Taxon
- chicoryCichorium intybuse0
- Treatment
- severe drought stress treatmente0
- Outcome
- photosynthesis ratee0
- Direction
- decreasede0
- Value
- 12.0 mgl CO2 m-2 s-3e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Drought stress decreased photosynthesis rate and minimum photosynthesis rate in chamomile and chicory were 9.0 mgl CO2 m-2 s-3 and 12.0 mgl CO2 m-2 s-3 under severe drought stress treatment”
Claim · model-written summary
Mild drought gave low chamomile chlorophyll a of 1.1 mg g-1.
- Taxon
- chamomilee0
- Treatment
- milde0
- Outcome
- chlorophyll a contente0
- Direction
- loweste0
- Value
- 1.1 and 1.2 mg g-1e0
Not reportedComparator
Verbatim
e0“In chamomile the lowest chlorophyll a content showed in mild and severe drought stress treatments (1.1 and 1.2 mg g-1)”
Claim · model-written summary
Severe drought gave low chamomile chlorophyll a of 1.2 mg g-1.
- Taxon
- chamomilee0
- Treatment
- severe drought stress treatmentse0
- Outcome
- chlorophyll a contente0
- Direction
- loweste0
- Value
- 1.1 and 1.2 mg g-1e0
Not reportedComparator
Verbatim
e0“In chamomile the lowest chlorophyll a content showed in mild and severe drought stress treatments (1.1 and 1.2 mg g-1)”
Claim · model-written summary
Severe drought gave minimum chicory chlorophyll a at 0.7 mg g-1.
- Taxon
- chicoryCichorium intybuse0
- Treatment
- severe drought stress treatmente0
- Outcome
- chlorophyll ae0
- Direction
- Minimume0
- Value
- 0.7 and 1.02 mg g-1e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Minimum chlorophyll a and b content of chicory obtained from severe drought stress treatment (0.7 and 1.02 mg g-1 respectively)”
Claim · model-written summary
Severe drought gave minimum chicory chlorophyll b at 1.02 mg g-1.
- Taxon
- chicoryCichorium intybuse0
- Treatment
- severe drought stress treatmente0
- Outcome
- chlorophyll a and b contente0
- Direction
- Minimume0
- Value
- 0.7 and 1.02 mg g-1e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Minimum chlorophyll a and b content of chicory obtained from severe drought stress treatment (0.7 and 1.02 mg g-1 respectively)”
Claim · model-written summary
Medium drought improved chamomile growth beyond well-watered conditions.
Verbatim
t0“Chamomile (Matricaria recutita L. Presov cultivar) and Chicory (Cichorium intybus L. local cultivar)”
e0“medium drought stress (irrigation at 75% of FC level) improved the growth and oil productivity even more than well watered conditions”
Claim · model-written summary
Severe drought raised essential oil content in the studied plants.
Not reportedComparator
Verbatim
t0“Chamomile (Matricaria recutita L. Presov cultivar) and Chicory (Cichorium intybus L. local cultivar)”
e0“severe water stress observed sizeable rise in essential oil contents”
Claim · model-written summary
Severe drought reduced essential oil yield in chicory.
- Taxon
- chicoryCichorium intybuse0
- Treatment
- severe drought stresse0
- Outcome
- oil yielde0
- Direction
- loweste0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“severe drought stress exhibited lowest oil yield in chamomile and chicory”
Claim · model-written summary
The authors recommend 75% field capacity irrigation for higher chamomile essential oil yield.
Verbatim
e0“chamomile and chicory should be irrigated at 75% FC level to attain higher essential oil yield”
Claim · model-written summary
The authors recommend 75% field capacity irrigation for higher chicory essential oil yield.
- Taxon
- chicoryCichorium intybuse0
- Outcome
- should be irrigated at 75% FC level to attain higher essential oil yielde0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“chamomile and chicory should be irrigated at 75% FC level to attain higher essential oil yield”
The same questions in other papers
drought · molecular: metabolites · Cichorium intybus (chicory)Positive and negative results
2 in the opposite direction
- negative
- negative
drought · growth · Cichorium intybus (chicory)Positive and negative results
3 papers in the same direction as this paper · 2 in the opposite direction
- positive
- positive
- negative
2 papers more in this group
See all 6 papers →in vitro · molecular: metabolites · Cichorium intybus (chicory)Results agree
2 papers in the same direction as this paper
- positive
- positive
drought · physiology: pigments · Cichorium intybus (chicory)Results agree
2 papers in the same direction as this paper
- negative
- negative
drought · physiology: photosynthesis · Cichorium intybus (chicory)Results agree
3 papers in the same direction as this paper
- negative
- negative
- negative
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.