Salvia splendens is a widely used ornamental bedding plant; however, the limited propagation method has decreased its quality and yield. Through years of selection, we have obtained a new variety of S. splendens with weak apical dominance and named it as ‘Cailinghong’. To establish an effective method for regeneration of S. splendens ‘Cailinghong’, different explants, including leaves, receptacles, petioles, stem nodes, and stem segments were used for adventitious bud induction. Next, various combinations of plant growth regulators (PGRs) were selected for bud and root induction, which were assessed by adventitious bud initiation rate and proliferation rate, as well as root induction rate. Meanwhile, the survival rate of transplanted plantlets was also calculated. As a result, stem nodes were found easy to be induced to form buds, and the optimum medium component was 1/2 Murashige and Skoog (MS) medium supplemented with 0.45 µM naphthalene acetic acid (NAA), 8.88 µM 6-benzylaminopurine (6-BA), and 2.46 µM 3-indolebutyric acid (IBA) for plantlets induction, whereas 1/4 MS medium supplemented with 2.23 µM NAA for root induction. Furthermore, the survival rate of transplanted plantlets was up to 80%, and all regenerated plantlets were normal in phenotype. Therefore, cultured in 1/2 MS medium with combined PGRs, whole plantlet of S. splendens ‘Cailinghong’ could be regenerated directly from stem node.
Ling Yu, Hongwei Chen, Peipei Hong, Hongli Wang and Kefeng Liu
Yuyu Wang, Faju Chen, Yubing Wang, Xiaoling Li and Hongwei Liang
High-frequency somatic embryogenesis and plant regeneration were achieved from immature cotyledonary-stage embryos in the endangered plant, Tapiscia sinensis Oliv. Plant growth regulators with different concentrations and combinations on embryogenesis capacity were studied. The optimal explants for in vitro somatic embryogenesis were immature embryos in T. sinensis. A high callus induction rate of 100% was achieved on Murashige and Skoog (MS) basal medium supplemented with 1.0 mg·Ll−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.5% (w/v) activated charcoal. Alternatively, a high induction rate (96.16%) of somatic embryogenesis was obtained on MS basal medium supplemented with the combination of 0.05 mg·L−1 α-naphthaleneacetic acid (NAA) and 0.2 mg·L−1 6-benzylaminopurine (6-BA), and somatic embryos proliferated fastest on the mentioned medium supplemented with 0.5% (w/v) activated charcoal and 3% (w/v) sucrose, inoculation of explants proliferating 21 times in the 23-day subculture. Of the 100 plantlets transferred to field after the acclimation, 95 (95%) survived. Based on the histocytological observations, the development of somatic embryos was similar to that of zygotic embryos. There were two accumulation peaks of starch grains in the embryogenic calli and in the globular-stage embryos, both closely related to the energy supply, and the embryoids were of multicelluar origin.
Chunyu Zhang, Xuesen Chen, Hongwei Song, Yinghai Liang, Chenhui Zhao and Honglian Li
Volatile compounds have a tremendous impact on fruit quality. We evaluated the volatile compound profiles of ripening wild apple fruit (10 Malus baccata accessions and three Malus prunifolia accessions) in the National Field Genebank for Hardy Fruits at Gongzhuling, China. Alcohols, esters, aldehydes, terpenes, hydrocarbons, ethers, heterocycles, carboxylic acids, and ketones were detected in the M. baccata and M. prunifolia fruit, with the first four being the main volatile compounds present. Of the 92 volatiles detected, esters were the most diverse (49 compounds). This wide range of abundant volatile compounds suggests that M. prunifolia is a good resource for breeding apple cultivars with novel and interesting flavors. The M. baccata accession ‘Zhaai Shandingzi’ and the M. prunifolia accession ‘Bai Haitang’ had the widest range of volatile compounds and the highest volatile compound contents of the accessions examined, and will therefore be good breeding materials for developing commercial lines with enhanced flavor and for widening the genetic diversity. The number of different ester compounds present was significantly positively correlated (r = 0.877) with the cube root of the weight of an individual ripe fruit. Principal component analysis (PCA) showed that the contents of ester compounds could be used to distinguish between M. baccata and M. prunifolia species. Therefore, ester compounds could be used as a reference of parental choice in apple breeding.