Tfg-Mi, a root-knot nematode resistance gene from fenugreek [Trigonella foenum-graecum] confers nematode resistance in tomato

Several root-knot nematode [Meloidogyne spp.] resistance genes have been discovered in different plants. For the first time, the Mi gene from fenugreek [Trigonella foenum-graecum] was detected in this study. A candidate root-knot nematode resistance gene [designated as Tfg-Mi] was isolated from the resistant fenugreek line Giza 3 by degenerate PCR amplification combined with the RACE technique. Also, another two candidate root-knot nematode resistance genes [designated as To-Mi11 and To-Mi12] were isolated from the resistant tomato [Lycopersicon esculentum] line Nemagard. Expression profiling analysis revealed that both genes were highly expressed in roots, leaves and flowers and expressed at a lower level in stems, but are not detectable in fruits. To verify the function of Tfg-Mi, a sense vector containing the genomic DNA spanning the full coding region of Tfg-Mi was constructed and transferred into root-knot nematode susceptible tomato plants. Sixteen transgenic plants carrying one to five copies of T-DNA inserts were generated from two nematode susceptible tomato cultivars. RT-PCR analysis revealed that the expression levels of Tfg- Mi gene varied in different transgenic plants. PCR assays showed that the resistance to root-knot nematodes was significantly improved in some transgenic lines compared to untransformed susceptible plants, and that the resistance was heritable

Micropropagation of some Egyptian date palm dry cultivars 1-maturation of somatic embryos

This study aimed to investigate the effect of adding different combinations of thiamine [5, 10, and 20 mg/l] and biotein [0, 1 and 2 mg/l] to culture medium on maturation of somatic embryos. Furthermore, the effect of MS-salt strength [[1/4], [1/2], [3/4] and full strength] on maturation of embryos was investigated. Embryonic calli were obtained from shoot tips and primordial leaves of three dry date palm cultivars [Bartamoda, Sakkoty and Malkaby]. Among the different treatments, a high frequency of mature embryos was proliferate from embryonic calli when cultured on [3/4] MS + 10 mg/l 2, 4-D + 3 mg/l 2iP + 10 mg/l thiamine HCL + 1mg/l biotein. This treatment gave 85.7%, 92.5% and 95.7% embryos with embryonic callus derived from shoot tip of Bartamoda, Malkaby and Sakkoty cultivars, respectively. However it was 58.7, 67.3 and 74.6 with those derived from primordial leaf explants of the three cultivars, respectively. Then, the obtained embryos of the three cultivars were successfully developed to shoots when recultured onto hormone free of [3/4] MS- salt medium