By using a modified biotin-streptavidin capturing method, a total of 20 polymorphic microsatellite markers were developed from Moringa oleifera Lam. (Moringaceae), a useful multipurpose tree. Twenty-four domesticated individuals, with germplasms of India and Myanmar, were used to screen polymorphism of these 20 microsatellite markers. The number of alleles per locus ranged from two to six. The expected and observed heterozygosity varied from 0.3608 to 0.7606 and from 0.0000 to 0.8750, respectively. Seven loci were significantly deviated from Hardy-Weinberg equilibrium. The availability of these microsatellite primers would provide a powerful tool for aspects of detailed population genetic studies of M. oleifera.
Jiang-Chong Wu, Jing Yang, Zhi-Jian Gu and Yan-Ping Zhang
Shanshan Seng, Jian Wu, Jiahui Liang, Fengqin Zhang, Qiuyan Yang, Junna He and Mingfang Yi
Starch accumulation is important during com development. ADP-glucose pyrophosphorylase (AGPase) is the rate-limiting enzyme in starch synthesis. AGPL is the large subunit of AGPase. Here, we isolated and characterized the large subunit of AGPase gene GhAGPL1 in gladiolus (Gladiolus hybridus). GhAGPL1 was highly expressed in sink organs (cormels and corms). The expression of GhAGPL1 was induced by glucose, sucrose, and mannitol, and it was repressed by abscisic acid (ABA). Overexpression of GhAGPL1 in the arabidopsis (Arabidopsis thaliana) apl1 mutant resulted in complementation of AGPase activity and thus starch synthesis. Silencing GhAGPL1 in gladiolus decreased the transcript level of GhAGPL1 and GhSus, and resulted in the reduction of AGPase activity and starch content in gladiolus corm and cormel. Meanwhile, sucrose content was higher in GhAGPL1-silenced corm. Surprisingly, silencing GhAGPL1 in gladiolus produced smaller corms and fewer number of cormels. Overall, GhAGPL1 contributed to the quality and quantity of gladiolus corms and cormels.
Long-na Li, Songjun Zeng, Feng Zheng, Zhi-lin Chen, Kun-lin Wu, Jian-xia Zhang and June Duan
Ten polymorphic microsatellite loci were isolated and characterized from an enriched genomic library of Paphiopedilum concolor (Batem.) Pfitzer. The number of alleles per microsatellite locus ranged from three to 11 with an average of 6.4 in a sample of 30 individuals from three populations. The observed and expected heterozygosity ranged from 0.200 to 0.800 and from 0.544 to 0.827, respectively. These microsatellites can be used as tools to investigate the genetic structure of P. concolor populations and relationship patterns with closely related taxa.
Song-jun Zeng, Zhi-lin Chen, Kun-lin Wu, Jian-xia Zhang, Cheng-ke Bai, Jaime A. Teixeira da Silva and Jun Duan
Nothodoritis zhejiangensis Z. H. Tsi is a rare and endangered epiphytic orchid restricted to a narrow distribution in China. The species is threatened with extinction as a result of loss of suitable habitats. An efficient propagation system is part of this species’ conservation plan. Seed germination reached 64.7% on Knudson's C (KC) medium containing 1.0 mg·L−1 α-naphthaleneacetic acid (NAA), 10% coconut water, and 0.1% activated charcoal. After 50 days culture, most callus (71.3%) from seed-derived protocorms formed on KC medium with 1.0 mg·L−1 2,4-dichlorophenoxyacetic acid and 10% coconut water. Callus could be subcultured 12 times during ≈2 years with more than a 3.0-fold increase from the third to the twelfth subculture. Furthermore, 84% of callus from the tenth sub-culture on KC media supplemented with 1.0 mg·L−1 NAA, 5% coconut water, and 0.1% activated charcoal formed protocorm-like bodies (PLBs). Many (57%) protocorms on KC medium containing 1.0 mg·L−1 6-benzylaminopurine and 10% coconut water formed PLBs. Both callus and PLBs formed simultaneously from different protocorms on KC medium containing 0.01 to 1.0 mg·L−1 thidiazuron and 10% coconut water. PLBs were incubated 12 times during ≈2 years with an approximate 2.4-fold increase per sub-culture. Both callus and PLBs maintained their competence to regenerate plantlets. Hyponex N026 medium supplemented with 1.0 mg·L−1 NAA, 50 g·L−1 banana homogenate, and 0.1% activated charcoal was suitable for plantlet formation and growth of 95.5% of plantlets that developed from PLBs. The roots of plantlets 2 cm in height or taller were wrapped in Chilean sphagnum moss and fixed to a fir bark block; 69.3% of plantlets survived after 180 days in a greenhouse. This protocol is an efficient means for the large-scale propagation of this endangered orchid.