A. Kazeminasab; M. Yarnia; M.H. Lebaschi; B. Mirshekar; F. Rajali
Abstract
Effects of vermicompost and plant growth promoting biofertilizers on the essential oil composition of lemon balm (Melissa officinalis L.) were studied under different irrigation conditions. The study was conducted in a split-split plot experiment based on a randomized complete block design with ...
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Effects of vermicompost and plant growth promoting biofertilizers on the essential oil composition of lemon balm (Melissa officinalis L.) were studied under different irrigation conditions. The study was conducted in a split-split plot experiment based on a randomized complete block design with three replications, at Research Institute of Forests and Rangelands.Treatments included irrigation in two levels (100 and 60% FC drought stress), vermicompost in three levels (0, 5 and 10t/ha) and plant growth promoting biofertilizers in four levels (Pseudomonas fluorescence, Azotobacter + Azospirillum, Azotobacter + Azospirillum + P. fluorescence, and the control). The essential oil components including citronellal, geraniol, neral, β-caryophyllene and methyl citronellat were studied. The interaction of irrigation × vermicompost showed significant effect on citronellal at P≤0.01 and on geraniol and methyl citronellat at P≤0.05. Mean comparison of irrigation indicated that the highest and lowest citronellal, geraniol, neral and β-caryophyllene, were obtained for drought stress and normal irrigation (100% FC), respectively. The highest and lowest methyl citronellat were recorded for the normal irrigation and drought stress (60% FC), respectively. Mean comparison of the effect of vermicompost showed that the highest (47.7%) and lowest (45%) citronellal were obtained for 10 t/ha vermicompost and control treatments, respectively. Application of 5 t/ha vermicompost resulted in the highest β-caryophyllene (6%). Mean comparison of the biofertilizers indicated that Azotobacter + Azospirillum + P. fluorescence had the highest citronellal (47.2%) and β-caryophyllene (5.9%); the lowest citronellal (45.6%) and β-caryophyllene (5.1%) were achieved in the control. Drought stress increased the essential oil compounds. Vermicompost just affected the citronellal. In addition, PGPR had a positive effect only on citronellal and β-caryophyllene.
B. Mirshekari
Abstract
In order to evaluate the effect of seed priming with iron and boron on germination parameters and yield of marigold (Calendula officinalis L.), laboratory and field experiments were conducted in Islamic Azad University, Tabriz Branch, with three replications in 2011. The studied treatments were the seed ...
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In order to evaluate the effect of seed priming with iron and boron on germination parameters and yield of marigold (Calendula officinalis L.), laboratory and field experiments were conducted in Islamic Azad University, Tabriz Branch, with three replications in 2011. The studied treatments were the seed priming with iron and boron at concentrations of 0.5%, 1%, 1.5% and 2%, distilled water as control and two combined treatments of Fe1.5%+B1% and Fe2%+B1%. Results revealed that seed priming with Fe 1% and 1.5% and B, alone or in the combined treatments, improved the seed germination speed of marigold as comared to the control. The seedling vigor index of primed seeds in Fe 1.5% solution increased up to 2.3. In the seeds primed with boric acid, the seedling vigor index was limited when the concentration of B in solution increased more than 1%. Dry flower yield in treatments of Fe1.5%+B1%, Fe1.5%, Fe2% and Fe2%+B1% were 39%, 34%, 24% and 28% more than control, respectively. Essential oil values among treatments ranged from 0.1 mL m-2 in B1.5% and B1% to 0.27 mL m-2 in Fe1.5%+B1%. Lower essential oil yield was obtained for the treatment of Fe2%+B1% (0.14 mL m-2) compared to B1.5% and B1%. Our results clearly showed that seed priming with iron and boron could be recommended as a method for improvement of essential oil yield in marigold.
