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In this work, we evaluated genetic diversity and population structure in eighty-eight Aegilops accessions using several physio-chemical traits such as shoot fresh and dry biomasses (SFW and SDW), photosynthetic pigments and activity of several antioxidant enzymes such as catalase, guaiacol peroxidase, peroxidase, and ascorbate peroxidase (APX), as well as 24 simple sequence repeat markers (SSR) under two control and water deficit stress conditions. The results indicated that water deficit stress dramatically affected SFW, SDW and photosynthetic pigments, while activity of all antioxidant enzymes were increased by water deficit stress compared to the control conditions. Statistical analysis of the phenotypic data showed a significant level of variation among the 88 investigated accessions. The results of correlation analysis showed that under both conditions photosynthetic pigments had a significant correlation with each other. The correlation between SDW and the activity of APX was positive and significant. The results of AMOVA using 24 SSR markers revealed that the genetic diversity observed among populations is more than within populations. Multivariate analyses grouped all investigated accessions in the clear groups based on their genomic constitutions. Based on results, 17 and 16 markers showed significant association with the measured traits under control and water deficit stress conditions, respectively. Our findings showed eight MTAs showed sufficiently stable expression across both control and stress conditions. Furthermore, several markers, especially Xgwm-455 associated with multiple traits across both conditions. In conclusion, these results could contribute to completing knowledge of the genetics and breeding for key physio-chemical properties.

To investigate the influence of cultivar, medium, and explants on production of somatic embryogenic callus in grapevine (Vitis vinifera) an attempt was made. After callus production, calli were transferred into GS1CA medium for embryogenesis. In GS1CA medium, anther explant of ‘Shahroodi’ cultivar showed the highest potential for production of embryogenic calli. Results showed that whole flower explants did not produce any embryogenic calli. In addition, leaf explants of ‘Red?Sultanina’ and ‘Flame Seedless’ were cultured on MS containing 1mg 2,4?D, 0.1 mg BA, 1 g/l casein hydrolisate, 20 g/l sucrose and 7 g/l agar were able to produce embryonic calli. After three months, calli were transferred to the MS with different concentrations of BA (1, 2 and 3.5 mg/l) and IAA (2, 5 and 15 mg/l). Results showed that among cultivars and different hormonal treatments, the medium containing 5 mg/l BA and 2 mg/l IAA induced maximum embryogenesis in ‘Flame?Seedless’ calli.Plant Tissue Cult. & Biotech. 26(2): 219-230, 2016 (December)

Mature zygotic embryos of Cycas revoluta Thunb. were used as explants to investigate direct and indirect organogenesis. Explants were incubated on half-strength Murashige and Skoog (½ MS) basal medium supplemented with various plant growth regulators, singly or in combination (all at 0.5 mg l-1): 6-benzyladenine (BA), kinetin (Kin), 2,4-dichlorophenoxyacetic acid (2,4-D), Kin×2,4-D, BA×Kin and BA×2,4-D. Cultures were placed at a low light intensity (4 µmol m-2 s-1 PPFD). Adventitious shoot regeneration was observed in the presence of 0.5 mg l-1BA after 35 days. The highest number of direct and indirect shoots per zygotic embryo was 3.67 and 29.67, respectively. Roots were induced on indirect shoots by continuous culture on rooting medium (½ MS,‏ 0.1 mg l-1 1-naphthaleneacetic acid) and hardened successfully in perlite. Each rooted plantlet with pinnate leaves and a primary tap root was individually isolated and acclimatized 185 days after the beginning of culture, with a 10% success rate.

Carrot (Daucus carota L.) In Vitro Regeneration Experiments were carried out for optimization of conditions for morphogenic callus production and regeneration of carrot (Daucus carota L.) using four cultivars cultivated in Iran. Hypocotyl segments were put on media supplemented with 0.2 mg·L-1 2,4-D for callus initiation and proliferation. Small portions of callus (25 mg) were cut and transferred to new media with different concentrations of 2,4-D including 0.2, 0.5 and 1 mg·L-1. MS (Murashige & Skoog 1962) and MSm (Masuda et al. 1981) media were used in the experiments to identify the differences between these two media according to callus, embryoid and plantlet production. Obtained results showed that low level of 2,4-D (0.2 mg·L-1) was more effective in morphogenic callus production although higher amounts of it (0.5 mg·L-1 and 1 mg·L-1) caused more callus growth. Kinetin in concentration of 0.1 mg·L-1 was more effective for regeneration than BAP used in concentration 1 mg·L-1 especially according to embryoid production. MSm medium was more useful than MS for callus production and regeneration of carrot plantlets. Among tested cultivars Nantes Improved had more capability to produce viable plantlets.

White blister rust caused by Albugo candida (Pers.) Kuntze is a common and often devastating disease of oilseed and vegetable brassica crops worldwide. Physiological races of the parasite have been described, including races 2, 7 and 9 from Brassica juncea, B. rapa and B. oleracea, respectively, and race 4 from Capsella bursa-pastoris (the type host). A gene named WRR4 has been characterized recently from polygenic resistance in the wild brassica relative Arabidopsis thaliana (accession Columbia) that confers broad-spectrum white rust resistance (WRR) to all four of the above Al. candida races. This gene encodes a TIR-NB-LRR (Toll-like/interleukin-1 receptor-nucleotide binding-leucine-rich repeat) protein which, as with other known functional members in this subclass of intracellular receptor-like proteins, requires the expression of the lipase-like defence regulator, enhanced disease susceptibility 1 (EDS1). Thus, we used RNA interference-mediated suppression of EDS1 in a white rust-resistant breeding line of B. napus (transformed with a construct designed from the A. thaliana EDS1 gene) to determine whether defence signalling via EDS1 is functionally intact in this oilseed brassica. The eds1-suppressed lines were fully susceptible following inoculation with either race 2 or 7 isolates of Al. candida. We then transformed white rust-susceptible cultivars of B. juncea (susceptible to race 2) and B. napus (susceptible to race 7) with the WRR4 gene from A. thaliana. The WRR4-transformed lines were resistant to the corresponding Al. candida race for each host species. The combined data indicate that WRR4 could potentially provide a novel source of white rust resistance in oilseed and vegetable brassica crops.

Saffron (Crocus sativus L.) is one of valuable and native plants in the land of Iran. By this investigation the best hormonal compositions for callus production from protoplast and for plantlet regeneration from callus were determined. To isolate protoplasts, the embryogenic calli were used. The embryogenic calli were immersed in enzymatic solution to degrade the cell walls. The treated mixture was filtered and then centrifuged at 100 g for 3-5 min and the resulted pellet was rinsed. After one step of washing and another step of centrifugation, the protoplasts were gently mixed with sterile sodium alginate solution and added to MS broth consisting 1% calcium chloride and 0.3 M manitol to form calcium alginates granules. The protoplast-containing granules were exposed to MS broth including 0.3 M manitol and various treatments of two kinds of auxins (2, 4-D and NAA) and three kinds of cytokinins (2ip, Kin, BAP), respectively in four rates of 0.1, 0.2, 0.5, 1.0 mg L(-1) for auxins and in three rates of 0.1, 0.2 and 0.5 mg L(-1) for cytokinins, incubated in dark at 22 +/- 2 degrees C for a period of 30 days. Out of all the treatment of 2, 4-D (1.0 mg L(-1)) and Kin (0.2 mg L(-1)) was the best in callus induction. In order to regenerate plantlets, the resulted calli were transferred to MS broth amended with different rates of ABA (0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mg L(-1)) so that they could pass the steps of embryonic maturation. The mature embryos were transferred to MS media with different rates of GA3 (0.0, 5.0, 15.0, 20.0, 25.0 and 30.04 mg L(-1)) to initiate germination. The germinated embryos were then placed in solid MS media with various rates of NAA and 2, 4-D auxins (0.0, 0.5, 1.0 and 2.0 mg L(-1)) and different levels of BAP and Kin cytokinins (0.0, 0.5, 1.0 mg L(-1)). Results from statistical analyses indicated the treatment of NAA and BAP (each 1 mg L(-1)) as the best hormonal treatment for the plantlet regeneration from the domestic saffron calli.