Improvement and breeding
A. Negari; M. Jami Al-Ahmadi; G. Zamani
Abstract
Medicinal plants are a rich and valuable source of secondary metabolites that are strongly influenced by the environmental factors, especially drought stress. In this regard, a greenhouse experiment was conducted on Thymus vulgaris L. as split plots in a randomized complete block design with three replications. ...
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Medicinal plants are a rich and valuable source of secondary metabolites that are strongly influenced by the environmental factors, especially drought stress. In this regard, a greenhouse experiment was conducted on Thymus vulgaris L. as split plots in a randomized complete block design with three replications. The main plot included three levels of moisture supply (40, 65, and 90% of potting soil field capacity (FC)) and the sub-plot was the elicitors levels including (1) control: without elicitor, (2) 150 µM cyclodextrin (CYC), (3) 75 nM coronatine (COR) + 150 µM CYC, (4) 150 nM COR + 150 µM CYC, (5) 150 µM methyl jasmonate (MJ) + 150 µM CYC, and (6) 300 µM MJ + 150 µM CYC. Except for the essential oil percentage, the other traits including the leaves proline content, electrolyte leakage, relative water content, plant height, canopy diameter, dry and fresh weight of shoots, dry weight of leaves and stems, and weight of essential oil had a very significant correlation with each other. The highest amount of leaves proline was obtained form the interaction of elicitors (levels 4 and 6) and the 40% FC level of moisture supply (3.88 and 3.94 μmol g-1 fresh leaf weight, respectively). The highest amount of plant height (28.3 cm), canopy diameter (17 cm), and relative water content (79%) was observed at the 90% FC level of moisture supply. The highest percentage of essential oil was obtained in the treatment of non-application of elicitor (2.67%) and the highest essential oil weight per plant (0.092 g plant-1) was observed in the treatment of non-application of elicitor at the 65% FC level of moisture supply. The mild stress increased the essential oil yield and the elicitor treatments decreased it.
F. Mirzaei; M.A. Behdani; M. Jamialahmadi
Abstract
In order to determine the appropriate planting date and evaluate the effect of sulfur on yield and yield components of pumpkin (Cucurbita pepo L.), a factorial experiment was conducted based on a randomized complete block design with three replications and two factors in Khalilabad, Khorasan Razavi, ...
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In order to determine the appropriate planting date and evaluate the effect of sulfur on yield and yield components of pumpkin (Cucurbita pepo L.), a factorial experiment was conducted based on a randomized complete block design with three replications and two factors in Khalilabad, Khorasan Razavi, in 2016 cropping year. The experimental factors were three planting dates (20 and 30 April and 10 May) and application of granular sulfur at four levels (0, 150, 300, and 450 kg ha-1). The results showed that planting date significantly affected the main stem length, branch number, total biomass, number of seeds per fruit, seed weight per fruit, 1000-seed weight, fruit and seed yield per hectare and oil percentage. Delayed planting from 20 to 30 April decreased the weight of 1000-seed by 14%. The highest seed yield was achieved by applying 300 kg sulfur per hectare. The fruit yield and seed oil percentage were higher in the first planting date and application of 300 kg sulfur ha-1. In general, this study showed that the first planting date (20 April), with the application of at least 300 kg ha-1 of sulfur fertilizer, would provide the best conditions for pumpkin yield.
M. Askary; M.A. Behdani; S. Parsa; M. Jamialahmadi; S. Mahmoodi
Abstract
This research was aimed to evaluate the effects of drought and manure on some physiological characteristics and yield of Thymus vulgaris L. and Thymus daenensis Celak.The study was conducted as factorial based on a randomized complete block design (RCBD) with three replications during crop years of 2015 ...
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This research was aimed to evaluate the effects of drought and manure on some physiological characteristics and yield of Thymus vulgaris L. and Thymus daenensis Celak.The study was conducted as factorial based on a randomized complete block design (RCBD) with three replications during crop years of 2015 and 2016 at the agriculture research farm of University of Birjand, Iran. Experimental factors were including: water stress at three levels (100%, 67% and 33% of field capacity), manure at two levels (30 tons.ha-1 and no manure), and two thyme species (Thymus vulgaris L. and Thymus daenensis Celak). Water stress reduced stomatal conductance, relative water content (RWC), Chl a, b and quantitative and qualitative yield; however, carotenoids content was increased under water stress. Although the quantity and quality yield of the study species decreased under water stress condition, manure application at 30 tons per ha led to the increased quantity and quality yield of both species. Thymus daenensis had more relative water content and quantity and quality yield (oil) in both crop years as compared with T. vulgaris. According to the results, T. daenensis can grow successfully in arid and semi-arid regions and could be recommended. There was a significant difference between two crop years; in the 2nd year, the quantity and quality yield (essential oil yield) of both study species increased.
