Big fruit size and nice red pigmentation combined with good flavor should be the major target for red-fleshed kiwifruit (Actinidia spp.) breeding programs. Genetic diversity and plant characteristics were evaluated on a set of kiwifruit accessions with predominantly red flesh to identify the superior individuals for further breeding or study of commercial application. The leading phenotypic characters varied widely among the accessions. Accession R reached average fruit weight ≈100 g, whereas it ranged from 43.15 to 84.71 g for the other accessions. Fruits of L and Q were flatter in shape than the others. The core volume accounted for fruit proportions ranging from 2.33% to 11.42%. ‘Chuhong’, ‘Honghua’, and K exhibited a round fruit apex, whereas most others showed a depressed apex. R, L, and Q had the highest a* values in the inner pericarp and also the most appealing visual coloration. Results revealed significantly higher soluble solid content (SSC), total sugar, and sugar/acid ratio in Q, R, and L. The 12 pairs of simple sequence repeat (SSR) markers were successfully used to characterize the genetic variability and confirm true-to-type identity for four accessions. However, the limited number of markers had no ability to discriminate among the other 11 accessions. Based on additional 28 SSRs, six of the indistinguishable accessions were confirmed to be genetically different, and three seemed to belong to the same clone vine. The results demonstrated that application of SSR data could improve the efficiency of identifying red-fleshed kiwifruit germplasm.
Yan-Chang Wang, Lei Zhang, Yu-Ping Man, Zuo-Zhou Li, and Rui Qin
Ninghang Wang, Chao Zhang, Sainan Bian, Pengjie Chang, Lingjuan Xuan, Lijie Fan, Qin Yu, Zhigao Liu, Cuihua Gu, Shouzhou Zhang, Yaling Wang, and Yamei Shen
Magnolia (Magnoliaceae) is widely cultivated for its beauty; however, despite this, the components of the different flower colors in Magnolia have not been elucidated. In this study, the color parameters of 10 Magnolia petals with different colors were measured by the Royal Horticultural Society Color Chart (RHSCC) and a color reader CR-10. The composition and content of the flavonoids in the petals were analyzed by high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) as well as HPLC with electrospray ionization and mass spectrometry (HPLC-ESI-MS2). All results showed that the 10 petals were divided into four color groups. Regarding the flavonoid composition, four types of anthocyanins, including Cyanidin-glucosyl-rhamnoside (Cy-GR), Cyanidin-glucosyl-rhamnosyl-glucoside (Cy-GRG), Peonidin-glucosyl-rhamnoside (Pn-GR), and Peonidin-glucosyl-rhamnosyl-glucoside (Pn-GRG), were identified, as well as 10 types of flavonols. The flavonols included isorhamnetin, quercetin, kaempferol, and their glycosides, which included rutinoside, rhamnose, and glucoside. Cyanidin and peonidin make Magnolia petals appear red-purple and purple, respectively, and the flavonols perform as evident auxiliary pigments, particularly quercetin. The Magnolia cultivar flower phenotypes sampled in this study differed by changes in their existing flavonoid content rather than by the appearance of new flavonoids. Consequently, this study provides a reference for further revealing the basis of Magnolia flower color and provides clues for color breeding.
Kang-Di Hu, Xiao-Yue Zhang, Sha-Sha Wang, Jun Tang, Feng Yang, Zhong-Qin Huang, Jing-Yu Deng, Si-Yuan Liu, Shang-Jun Zhao, Lan-Ying Hu, Gai-Fang Yao, and Hua Zhang
Hydrogen sulfide (H2S) has been proven to be a multifunctional signaling molecule in plants. In this study, we attempted to explore the effects of H2S on the climacteric fruit tomato during postharvest storage. H2S fumigation for 1 d was found to delay the peel color transition from green to red and decreased fruit firmness induced by ethylene. Further investigation showed that H2S fumigation downregulated the activities and gene expressions of cell wall–degrading enzymes pectin lyase (PL), polygalacturonase (PG), and cellulase. Furthermore, H2S fumigation downregulated the expression of ethylene biosynthesis genes SlACS2 and SlACS3. Ethylene treatment for 1 d was found to induce the expression of SlACO1, SlACO3, and SlACO4 genes, whereas the increase was significantly inhibited by H2S combined with ethylene. Furthermore, H2S decreased the transcript accumulation of ethylene receptor genes SlETR5 and SlETR6 and ethylene transcription factors SlCRF2 and SlERF2. The correlation analysis suggested that the fruit firmness was negatively correlated with ethylene biosynthesis and signaling pathway. The current study showed that exogenous H2S could inhibit the synthesis of endogenous ethylene and regulate ethylene signal transduction, thereby delaying fruit softening and the ripening process of tomato fruit during postharvest storage.