Hamed Ebrahimzadeh; Mahmoud Lotfi; Mohammad Sadat-Hosseini
Abstract
Doubled haploid method via parthenogenesis induction still remained prominent in Cucurbitaceae breeding due to drastic reduction in time and cost of newly released lines. In this study, different doses of Gamma ray (25, 50, 75, 100, and 200 Gy) were used to irradiate pollen grains for induction of parthenogenetic ...
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Doubled haploid method via parthenogenesis induction still remained prominent in Cucurbitaceae breeding due to drastic reduction in time and cost of newly released lines. In this study, different doses of Gamma ray (25, 50, 75, 100, and 200 Gy) were used to irradiate pollen grains for induction of parthenogenetic haploid embryos in oilseed pumpkin (Cucurbita pepo var. ‘Styriaca’). Parthenogenetic embryos at different developmental stages were rescued in vitro and 348 plants were obtained, of which 134 were recognized as haploid by ploidy analysis. The highest rate of haploid plants was obtained from globular (25.3%) and torpedo (23.8% plants) embryos followed by arrow-tip (13.4%), torpedo (10.5%), stick (10.5%), heart (9%), and cotyledonary (7.5%), respectively. All doses, except 200 Gy, were effective for induction of embryos and haploid plants; in a way that the highest number of haploids was obtained by 100 Gy. Our results indicated that parthenogenetic haploid embryos could be efficiently induced in C. pepo if proper Gamma ray dose and developmental stage of embryos are selected.
Hamid-Reza Fallahi; Morteza Ghorbany; Alireza Samadzadeh; Mahsa Aghhavani-Shajari; Amir-Hassan Asadian
Abstract
In this study effect of irrigation managements including irrigation after 100 and 200 mm pan evaporation as normal and deficit irrigation respectively was investigated in Roselle plants. Effects of humic acid (including 0 and 4 kg ha-1) and mycorrhizal inoculants (including Glomus versiforme (GV) and ...
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In this study effect of irrigation managements including irrigation after 100 and 200 mm pan evaporation as normal and deficit irrigation respectively was investigated in Roselle plants. Effects of humic acid (including 0 and 4 kg ha-1) and mycorrhizal inoculants (including Glomus versiforme (GV) and Rhizophagus irregularis (RI)) were also studied on growth, yield and mycorrhizal symbiosis index of Roselle plants. Drought stress reduced the amounts of morphological indices and yield components, while mycorrhizal treatment particularly RI inoculation and to a lower extent humic acid application reduced the negative impacts of water deficit on growth and yield of Roselle plants. Both inoculants of mycorrhizal fungi increased the economical yield of Roselle under drought stress condition, where the amount of calyx yield for RI, GV and control in 200 mm pan-evaporation treatment was 130, 127 and 66 kg ha-1, respectively. In addition, the highest root mycorrhizal frequency was obtained at normal irrigation × humic application × RI (95%) and the lowest value was observed at deficit irrigation × no-humic × no-mycorrhizal inoculation (31.6%) treatment. In conclusion, combined effects of experimental factors showed that seed inoculation of plants by mycorrhiza and to some extent application of humic acid are two reliable strategies for Roselle production under deficit irrigation.
