A high efficient in vitro regeneration protocol was developed from leaf explants of the female 'Red Sun' kiwifruit (Actinidia chinensis) and the multiplication coefficient and rooting rate of adventitious buds were also optimized. This method does not require formation of callus tissues which leads to somaclonal variations. The results show that the adventitious buds developing directly from explants tissue were noticed after 30 d of culture. The maximum regeneration frequency of adventitious buds is 100% and 18.67 shoots was observed in each leaf explants when MS medium was supplemented with 3.0 mg/L BA+1.0 mg/L NAA. The optimal culture medium for bud multiplication is MS+2.0 mg/L BA+1.0 mg/L NAA+0.1 mg/L GA3 and the multiplication coefficient reached 8.63. On the rooting medium with 1/2 MS+0.8 mg/L IBA for 15 d, the adventitious plantlets were transferred into matrix perlite supplied with 1/2 MS liquid medium for 15 d and the rooting rate reached 100%. 95 out of 98 plantlets (96.94%) survived acclimatization, producing healthy plants in the greenhouse. Taken together, a highly efficient regeneration method via leaf explants of 'Red Sun' kiwifruit was successfully established. This protocol may be useful for micropropagation and genetic transformation studies of 'Red Sun' kiwifruit.
Actinidia ; growth & development ; Plant Growth Regulators ; pharmacology ; Plant Leaves ; growth & development ; Regeneration ; physiology ; Tissue Culture Techniques ; methods

Bacterial canker caused by Pseudomonas syringae pv. Actinidiae is one of the most important diseases of kiwifruit (Actinidia chinensis) and leads to considerable yield losses. In order to obtain transgenic plants with resistance for 'Red Sun' kiwifruit to canker disease, a non-specific lipid transfer protein-like antimicrobial protein gene (LJAMP2) from motherwort (Leonurus japonicus) was introduced into 'Red Sun' kiwifruit through Agrobacterium-mediated transformation. After two days of co-cultivation with A. tumefaciens strain LBA4404 harboring 35S:LJAMP2, the transformed explants were transferred to the selection medium containing 25 mg/L kanamycin+3.0 mg/L BA+1.0 mg/L NAA. The regeneration efficiency of kanamycin-resistant shoots reached to 85%. All (100%) of kanamycin-resistant shoots rooted on half-strength MS medium supplemented with 0.8 mg/L IBA and a total of 40 regenerated plantlets were obtained. PCR and histochemical GUS activity analysis show that 23 of 40 lines (57.50%) were positive, suggesting that the LJAMP2 gene was integrated into the genome of 'Red Sun' kiwifruit. Taken together, we established an efficient genetic transformation method for 'Red Sun' kiwifruit using A. tumefaciens and the transformation frequency reached 5.11%. This protocol will be useful for the genetic breeding of 'Red Sun' kiwifruit for improvement of disease resistance.
Actinidia ; genetics ; Agrobacterium ; Antigens, Plant ; genetics ; Carrier Proteins ; genetics ; Leonurus ; Plant Proteins ; genetics ; Plants, Genetically Modified ; genetics ; Transformation, Genetic

Objective To explore the application value of fractional anisotropy(FA)values of magnetic resonance diffusion tensor imaging(DTI)parameters in rat rat glioma grading.Methods Sixty-seven female Wistar rats were divided into the experi-mental group(n=57)and control group(n=10)according to the random number table method.All the surviving rats were exam-ined by 3.0T DTI at 1-2 weeks(22 cases)and 3-4 weeks(35 cases)after inoculation,and the FA values of the tumor were ob-tained and compared with the pathological results.Results Among 57 tumor-loading rats,there were 18 low-grade gliomas and 39 high-grade gliomas.DTI showed that the FA value of high-grade gliomas was higher than that of the low-grade glioma,the differ-ence was statistically significant[(0.167 ± 0.035)vs.(0.147 ± 0.015),t=2.34,P<0.05].Conclusion The FA value of DTI pa-rameters can provide accurate,reliable and noninvasive imaging information for preoperative glioma grading.