Research paper
Musa Ibrahim Saheed; Ikhajiagbe Beckley; Geoffrey O. Anoliefo; Alexander O. Orukpe
Abstract
The Earth has become increasingly overcrowded as a result of rapid urbanization and population growth, with strong predictions that its carrying capacity could be overstretched soon. As a result, it is important to test the possibilities of growing plants under space exploration conditions, especially ...
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The Earth has become increasingly overcrowded as a result of rapid urbanization and population growth, with strong predictions that its carrying capacity could be overstretched soon. As a result, it is important to test the possibilities of growing plants under space exploration conditions, especially gravitational balance. Since microgravity impedes plant development, it is important to evaluate the extents by which plant growth stimulators can reverse or enhance this trend. A total of 12 maize seeds were weighed and placed sideways in petri dishes and inoculated with plant growth stimulators, indole acetic acid (IAA), gibberellic acid (GA), and ascorbate (AA). They were clinorotated at different rates (0.5, 1.0, and 2.0 rpm), while the control seeds were just placed on a balanced table. Results of this research showed that under microgravity, the maize seeds had a decreased level of germination percentage with increasing clinorotation rates at 72 hrs, compared to the control group. But when stimulated with IAA, GA and AA, they improved in germination percentage, compared to the control, even under microgravity conditions. The seedling dry weight, germination time and other germination parameters also showed similar improvements. Comparatively, the three growth stimulators showed no major variations in their ability to improve germination percentage under micro-gravitational impact. However, IAA caused more improvements in seedling vigor, compared to the other growth regulators, while GA had more effects on the rate of germination. This research confirmed the possibilities of improving germinability in maize seeds under space exploration conditions.
Research paper
Rasoul Heydarnajad Giglou; Mousa Torabi Giglou
Abstract
Cape gooseberry is a climacteric, temperature-sensitive fruit from the Solanaceae family. Its quality and quantity are characterized by phenolic and antioxidant substances, the stability of which depends on temperature and storage conditions. In this research, the effects of calyx cover (fruits without ...
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Cape gooseberry is a climacteric, temperature-sensitive fruit from the Solanaceae family. Its quality and quantity are characterized by phenolic and antioxidant substances, the stability of which depends on temperature and storage conditions. In this research, the effects of calyx cover (fruits without calyx cover and fruits covered with calyx) and storage conditions were evaluated on the storage life of Cape gooseberry fruits. For this purpose, the fruits were kept in with and without calyx conditions at three temperature levels of 10, 15, and 20 °C for 30 days. The results showed that, at the end of storage, the titratable acidity, total soluble solids, vitamin C, total flavonoid, and total antioxidants decreased significantly. However, total phenol content and flavor index increased during the storage period. The increase in total flavor and phenol content during storage can be due to a significant reduction in the titratable acidity (as reflected in the flavor index), because of cellular destruction and cold damage. In addition, at the end of the storage period, the calyx-covered fruits which were stored at 10 °C had good physicochemical and antioxidant qualities. The highest titratable acidity (0.633%), soluble solids (14.96%), vitamin C, and total antioxidants (59.33%) were observed in fruits covered with calyx at 10 °C. Also, the results of this study showed that storing berries at cooler temperatures increased the shelf life and maintained the quality of the Cape gooseberry.
Research paper
Shima Alaei; Nasser Mahna
Abstract
Glycine betaine (GB) plays a crucial role in plants and in their response to abiotic stress. This experiment was conducted to evaluate the application of glycine betaine (GB) and its ability to alleviate the effects of salinity stress (SS) on fruit yield and ion accumulation in strawberry (Fragaria × ...
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Glycine betaine (GB) plays a crucial role in plants and in their response to abiotic stress. This experiment was conducted to evaluate the application of glycine betaine (GB) and its ability to alleviate the effects of salinity stress (SS) on fruit yield and ion accumulation in strawberry (Fragaria × ananassa Duch cv. Paros). Three levels of SS (0, 20, and 40 mM NaCl) and GB (0, 5, 10 mM) were used on the plants in a greenhouse experiment. The results indicated that increasing the salinity level reduced the yield and altered the dynamism of ion accumulation. Leaf area, relative water content (RWC), leaf fresh weight, and yield decreased under salinity stress (36.7%, 9.2%, 28%, and 41%, respectively), especially at 40 mM NaCl. Under SS, there was an increase in Na content of the roots, fruits, and leaves (78%, 54%, and 78%, respectively) as well as in K content of the fruits (50%), but with a decrease in the K content of the leaves (29%) and the roots (25%), and P content of the leaves (55%). Overall, salinity increased the Na content, but reduced the K/Na ratio. Salinity and glycine betaine interactions had a significant effect on the Na content of the roots and leaves, the K content in the leaves, and K/Na ratio in the leaves and roots. At 40 mM NaCl, using 10 mM GB reduced the leaf and root Na content by 22% and 30%, respectively. Although the application of exogenous GB on strawberry changed the pattern of ion accumulation, it was not effective in diminishing the adverse effects of salinity stress on strawberry plants cv. ‘Paros’.
Research paper
Tahereh Goudarzi; Leila Tabrizi; Hossain Ali Alikhani; Vahideh Nazeri; Farzad Najafi
Abstract
To evaluate the effects of four licorice plant growth-promoting bacteria (PGPB), i.e. Pantoea agglomerans (S72), Serratia rubidaea (S28) Pseudomonas azotoformans (E101), Pseudomonas frederiksbergensis (E56) on licorice seed germination and seedling growth, two experiments were conducted at the Research ...
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To evaluate the effects of four licorice plant growth-promoting bacteria (PGPB), i.e. Pantoea agglomerans (S72), Serratia rubidaea (S28) Pseudomonas azotoformans (E101), Pseudomonas frederiksbergensis (E56) on licorice seed germination and seedling growth, two experiments were conducted at the Research Laboratory and Greenhouse, University of Tehran in 2019. Treatments were bacterial strains in eight levels (sole or in combination) and growing media at four levels of M1 (sand + perlite (1: 1)), M2 (soil + cow manure), M3 (soil + mycorrhiza fungi) and M4 (soil + mycorrhiza fungi+ cow manure). Germination quality criteria and some morphological traits of two-month-old seedlings were evaluated. The results of seed germination showed that in most of the evaluated traits, bacterial treatments performed better than the control, although in some cases, there were no significant differences with the control. Also, in some cases, endophytic bacteria had an effective role in improving seed germination index compared to rhizospheric bacteria. According to the experiment results of seedling growth, M4 in combination with two endophytic bacteria (E101 and E56), of the Pseudomonas genus in licorice plants, had a superior performance in improving the initial growth and establishment qualities of the licorice plants. Regarding most of the traits, the co-application of mycorrhiza with S28 (M3B3) showed the lowest values. The results of this study indicated the potential use of licorice endophytic bacteria as a source of biofertilizer for the improvement of licorice seed germination and growth and, if possible, for similar applications in other plant species.
Abbreviations
M1 (sand + perlite (1: 1)), M2 (soil + cow manure), M3 (soil + mycorrhiza fungi) and M4 (soil + mycorrhiza fungi + cow manure), Plant growth-promoting bacteria (PGPB), Indole-3-acetic acid (IAA), B1 (Pantoea agglomeransz (S72)), B2 (Serratia rubidaea (S28)), B3 (Pseudomonas azotoformans (E101)), B4 (Pseudomonas frederiksbergensis (E56)
Research paper
Mohammad Hossein Azimi
Abstract
Freesia belongs to the family Iridaceae and is one of the most popular bulbous species that can be used both as a cut flower and as a pot flower, depending on the situation. This study was carried out to produce new, high-quality offspring by intervarietal hybridization between five commercial cultivars ...
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Freesia belongs to the family Iridaceae and is one of the most popular bulbous species that can be used both as a cut flower and as a pot flower, depending on the situation. This study was carried out to produce new, high-quality offspring by intervarietal hybridization between five commercial cultivars of freesia hybrids. Eighteen morphometric traits, which were mostly related to flower organs, were evaluated on twelve progenies and five parental plants in a randomized complete block design (RCBD), with three replications (2014-2018). The assessments were based on instructions of the International Union for the Protection of New Varieties of Plants (UPOV). The highest heritability of broad-sense traits was related to the outer segmental width of the perianth and the inner segmental width and length of the perianth. The lowest heritability was related to the length of stem between the first and second flowers. The number of flowers and buds had the most significant, positive correlation with spike length (r=+0.75). Likewise, the strongest positive, significant correlation was observed between the length of the inner and outer segments of the perianth (r=+0.79). Superior progenies consisted of the 20A hybrid, with a white color, which originated from the parental cross P1×P5. The 3A hybrid, with a yellow color, was obtained from the parental cross P2×P5, and the 28P hybrid, with a reddish brown color, was obtained from the parental cross P4×P5. These progenies were superior in terms of important traits such as plant height, branch number of the peduncle, spike length, number of buds and florets, compared to the parents. Thus, intervarietal hybridization in this research was proved as an effective way to generate new phenotypic variations of freesia hybrids, thereby providing opportunities to produce new plant materials for breeding purposes and release new cultivars.
Research paper
Md. Serazul Islam
Abstract
During the dry season (November to April), a field experiment was carried out at the Agricultural Field Research Center of the Bangladesh Open University, Gazipur. The effects of different levels of irrigation with various mulches were evaluated on the growth and yield of tomatoes. The trial comprised ...
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During the dry season (November to April), a field experiment was carried out at the Agricultural Field Research Center of the Bangladesh Open University, Gazipur. The effects of different levels of irrigation with various mulches were evaluated on the growth and yield of tomatoes. The trial comprised raised-bed furrow irrigation methods with three mulching treatments (i.e. without mulch, black polyethylene mulch and grass straw mulch) and two irrigation plans (6-day and 3-day intervals). The 6 treatments were designed in a randomized complete block (RCB) design in three replicates. In response to the 6-day and 3-day irrigation intervals, raised-bed furrow irrigation, with black polyethylene mulch, resulted in a significantly higher yield (96.46 t/ha and 102.19 t/ha) compared to the effect of no mulch on the yield (77.70 t/ha and 82.04 t/ha), respectively. The use of grass straw mulch (87.15 t/ha and 91.76 t/ha) also resulted in a significant yield, compared to no mulch. All three factors significantly influenced unit crop weight, fruit size at the age of 16, 18 and 20 weeks after transplanting, marketable fruit yield, plant water consumption and water use efficiency. The interaction between raised-bed furrow irrigation, mulching and irrigation schedule had a significant influence on the water use efficiency (WUE) of tomato production. The raised-bed furrow irrigation method in a two-row crop cultivation pattern was statistically equivalent in terms of WUE if it was mulched by black polyethylene and irrigated every 3 days.