Negar Heidarian, Taher Barzegar, Zahra Ghahremani, Jaefar Nikbakht,
Volume 7, Issue 26 (11-2018)
Abstract
In order to evaluate the effect of water deficit stress on yield and physiological characteristics of some Iranian melon accessions, an experiment was carried out in a split plot based on randomized complete block design with three replicates in research filed of university of Zanjan during 2015. Treatments consisted arrangement of three irrigation levels (100, 70 and 40% ETc) and 7 Iranian melon accessions (Ghalam Ghash, Roshe, Zerke, Rish Baba, Ghobadloo, Garake and Kalyar). In this experiment, antioxidant enzyme activity, stomatal conductance, proline content, leaf relative water content, cell membrane stability index, hydrogen peroxide and malondialdehyde was measured. The results showed that water deficit stress reduced cell membrane stability index, leaf relative water content and stomatal conductance) and yield. The highest proline content in “Garake”, and maximum catalase and peroxidase enzymes activity was observed in “Zerke” and “Gobadloo” respectively under deficit irrigation 40% ETc. Hydrogen peroxide and malondialdehyde contents significantly increased under water deficit stress. According to the results, the highest (65.17%) and lowest (41.16 %) yield reduction was observed in “Zerke” and “Rish Baba” accessions respectively under irrigation 40% ETc compared to irrigation 100% ETc, thah were sensitive and tolerance accession to the water deficit stress, respectively.
Seyed Hassan Masomi, Ali Imani, Saeed Seyfzade, Seyed Ali Reza Valadabady, Hamid Reza Zakerin,
Volume 11, Issue 52 (3-2023)
Abstract
In this study, the reaction of germination and plantlet growth different chickpea cultivars (Arman, Azad, Binalood and Hashem) in relation to osmotic stress due to polyethylene glycol solution (-2, -4, -6 and -8bar) and control (distilled water) using factorial design in completely randomized with four replications was evaluated. In this study, there was a significant difference between the different potentials of drought stress for all measured traits with 99% probability. With the reduction of water potential, the seed germination, germination rate, rootlet length, stemlet length, rootlet wet weight, rootlet dry weight, stemlet wet weight, stemlet dry weight, plantlet wet weight, as well as plantlet dry weight decreased. Also, proline and Fv/Fm (the efficiency quantum of the photosystem II) of cultivars at two levels of control and glycol polyethylene solution at the level of -2bar was different. So that the Hashem cultivar showed the highest amount of proline in the polyethylene glycol solution -2bar. However, the Fv/Fm had a reversed relationship with drought stress. That is, drought stress leads to a reduction in the Fv/Fm. The maximum amount of Fv/Fm was found in the Hashem cultivar under drought stress condition, and the lowest amount in Azad cultivar in stress conditions. The results of activity of antioxidant enzymes in this study showed that drought-resistant cultivars such as Hashem is to drought stress by increasing the capacity of the antioxidant system to remove reactive oxygen species and prevent membrane peroxidation Overall, the commercial cultivar Hashem showed drought tolerance at high stress levels, indicating their potential for production applications.
