Sadegh Asadi; Hosein Moghaddam; hasanali Naghdibadi; Mohamadreza Naghavi; Ali Reza Salami
Abstract
The present study has been conducted to investigate the duration of growth period of different cannabis (Cannabis sativa L.) ecotypes and their responses to water stress based on a factorial completely randomized experiment design in the greenhouse condition at the University of Tehran in 2017. Irrigation ...
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The present study has been conducted to investigate the duration of growth period of different cannabis (Cannabis sativa L.) ecotypes and their responses to water stress based on a factorial completely randomized experiment design in the greenhouse condition at the University of Tehran in 2017. Irrigation levels include 50%, 75%, and 100% of field capacity, with the ecotypes being Urmia, Sanandaj, Tabriz, Dasht-e-Moghan, Rasht, Khomein, Daran, Qom, Shahroud, Kerman, Tabas, and Saravan. Results show that Rasht and Khomein ecotypes have had the highest and lowest duration of germination phase and growth degree-days (GDD1), respectively. The highest duration of vegetative, flowering and maturation phases belong to Dasht-e-Moghan, Rasht, and Dasht-e-Moghan ecotypes with 71.33, 30, and 46.66 (days), respectively, at 100% field capacity. The lowest durations of these phases could be seen in Tabas, Tabriz, and Saravan ecotypes with 42, 16, and 17 (days), respectively, at 50% field capacity. Also, the highest values of growth degree-days for vegetative (GDD2), flowering (GDD3), and maturation (GDD4) phases for Dasht-e-Moghan, Kerman, and Dasht-e-Moghan ecotypes with 1788, 836, and 1169 (0C.d), respectively, at 100% field capacity, with their lowest values belonging to Tabas, Tabri,z and Saravan with 1039, 413, and 448 (0C.d), respectively, at 50% field capacity. Based on growth period duration and cumulative growth degree-days (total GDD), Tabas and Dasht-e-Moghan ecotypes are found as earliest and latest ecotypes, respectively.
Alireza Khaleghi; Rohangiz Naderi; Alireza Salami; Mesbah Babalar; Iman Roohollahi; Gholamreza Khaleghi
Abstract
Drought is one of the most important environmental factors which limit the growth of woody plants. Iran is located in arid and semi-arid area therefore the growth and cultivation of ornamental trees and shrubs were limited. For this purpose, effect of foliar-applied salicylic acid and/or spermidine (0, ...
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Drought is one of the most important environmental factors which limit the growth of woody plants. Iran is located in arid and semi-arid area therefore the growth and cultivation of ornamental trees and shrubs were limited. For this purpose, effect of foliar-applied salicylic acid and/or spermidine (0, 100, 500 and 1000 µmol) on reduce drought stress injuries of one-year seedlings ofOsage orange (Maclura pomifera) was examinedat the Horticultural Research Station, University of Tehran, in 2013.This study was conducted as a factorial based on completely randomized design with three replications. First, PGRs were foliar-applied for two consecutive days in during the early morning and the late afternoon and then plants were droughted by withholding water for 10 days. The damaging effects of drought on membrane leakage were reversed by low concentrations of salicylic acid and/or spermidine. Also, salicylic acid and spermidin at a concentration of 100 µmol stimulated catalase and superoxide dismutase activity, enhanced proline and chlorophyll content and maintained photochemical efficiency of chlorophyllunder drought stress. But Spermidine and salicylic acid at high concentrations were ineffective and/or inhibitors. Finally, our results showed that 100 µmol salicylic acid and/or spermidine maybe the best concentration for increasing of drought tolerance in young seedling, especially during transplanting and planting in permanent location.
Shirin Dianati; Mohsen Kafi; Masoud Mirmasoumi; Valiollah Mozaffarian; Ali Reza Salami
Abstract
Five different media with two concentrations and kinds of carbohydrates and peptone treatments were examined for their effectiveness in promoting asymbiotic seed germination of Epipactis veratrifolia. Results revealed significant differences between media on seed germination percentage and protocorm ...
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Five different media with two concentrations and kinds of carbohydrates and peptone treatments were examined for their effectiveness in promoting asymbiotic seed germination of Epipactis veratrifolia. Results revealed significant differences between media on seed germination percentage and protocorm growth and Fast medium has the best effect on both. Carbohydrate treatments had significant effect on seed germination percentage but not on protocorm growth. Modified Fast medium with 5gr l-1 fructose and 12 gr l-1 sucrose and 2 gr l-1 peptone (MFH2P2) was the best medium for seed germination (49.6%) and Modified Fast medium with 30 gr l-1 sucrose and 2 gr l-1 peptone (MFH1P2) was the best medium for protocorm growth (17.3 mm). Media, carbohydrate and peptone influence seed germination percentage, while media and peptone alone influence protocorm growth. In addition, use of in vitro culture significantly reduced relatively long period of time which is necessary for seed germination and protocorm plantlets growth in natural conditions (approximately 2 years).