The genus Hydrangea comprises 70-80 species, some of which have economic importance as flowering plants. Japan has at least 71 hydrangea diseases and approximately one-third of the world’s recorded hydrangea diseases. A large number of hydrangea diseases in Japan are known primarily due to the long history of disease studies since 1892, and the pathogen diversity caused by Japan’s high humidity and temperature ranges. Recently, new diseases have been found in several high-value cultivars that have been grown as potted plants in greenhouses in Japan. Such growing environments with high humidity and temperature may have enhanced development of the new diseases. An overall risk assessment is needed to ensure proper management of both old and new diseases of hydrangeas. This review lists all known hydrangea diseases recorded in Japan, compared them to global records, and reveals the diversity as well as the uniqueness of the diseases in the country. In addition, eight diseases, i.e., ring spot, bacterial leaf spot, stem and root rot, powdery mildew, gray mold, leaf spot/stem rot, anthracnose, and leaf spot, which are currently problematic in Shimane Prefecture, Japan, are addressed based on four features: 1) symptoms, 2) distribution, 3) occurrence, and 4) control.
Citrus species grown in Japan are affected by several viruses and viroids, including satsuma dwarf virus, citrus vein enation virus, citrus exocortis viroid, and other citrus viroids. Recently, a comprehensive review was made on the occurrence, history, and research of the following three major citrus viruses in Japan: satsuma dwarf virus, citrus tatter leaf virus (apple stem grooving virus), and citrus tristeza virus (Iwanami 2022). As a sequel, this study reviews the occurrence, history, and research development of citrus viroids as well as minor citrus viruses in and around Japan.
The recent development of homologous recombination-mediated gene targeting (GT) techniques has made it easy to modify nucleotide sequences in plant genomes. Backcross breeding following GT provides transgene-free plant lines with high probability. However, owing to the possibility of unintentional transgene introduction during genetic transformation, analytical methods may be necessary to reliably and comprehensively detect transgenes remaining on a plant genome. Herein, we conducted an analysis based on whole-genome sequencing. We analyzed the GT rice DNA using a next-generation sequencer, and we performed data analysis to find the transgene integration on the genome. All results supported the absence of transgenes in GT rice. Our genome integrity evaluation method could also be applicable to plant lines produced using other genome-editing technologies such as CRISPR/Cas9.
To utilize scent as an added value of cut tulip flowers, it is necessary to reveal how the scent changes during anthesis. This study investigated the daily changes in scent emission of cut flowers under different temperatures (13℃, 18℃, and 23℃), using Tulipa ‘Niigata 13 go.’ At 23℃, the total emission was high and decreased with tepal senescence. The total emissions at 18℃ increased later than those at 23°C. The lowest temperature (13°C) resulted in overall low scent emissions compared to those at the highest temperature of 23°C. Additionally, as the tepals matured, the scent composition changed from monoterpene to benzenoid. These changes in the quantity and composition of scents were observed earlier at higher temperatures. One of the underlying factors is presumed to be the rapid maturation and senescence of flowers at high temperatures. Therefore, both flower maturation and temperature are required for sufficient scent emission. Furthermore, the emissions of scent components with the same biosynthetic pathway tended to behave similarly. The scent of cut tulip flowers changed both quantitatively and qualitatively during anthesis, and these changes were affected by temperature. This result suggests that the scent of cut tulip flowers can be partially controlled by artificial temperature management.
This study aimed to determine the effects of vitamin C supplementation on antioxidant and inflammatory status and cell viability of bovine peripheral blood mononuclear cells. Peripheral blood mononuclear cells (PBMCs) were isolated from eighteen clinically healthy Japanese Black calves in this study. PBMCs were cultured with vitamin C (vitamin C group) and without vitamin C (control group) and stimulated with or without lipopolysaccharide (LPS). As a result, the total antioxidant capacities, which are the reducing power of components from Fe3+ to Fe 2+, in the cell culture supernatant with or without LPS stimulation were significantly higher in the vitamin C group than those in the control group (P < 0.05, P < 0.01, respectively). Tumor necrosis factor-alpha in the cell culture supernatant with LPS stimulation was significantly higher in the control group than that in the vitamin C group (P < 0.05). The viability of cells cultured with LPS stimulation was significantly higher in the vitamin C group than that in the control group after 72 h of culture (P < 0.05). These results suggested that vitamin C is related to the antioxidant and anti-inflammatory properties and cell viability of PBMCs obtained from calves.
A significant quantitative trait locus (QTL) for murine litter size, Lsq1, was previously identified on chromosome 7 in the female backcross progeny of ♀(♀C57BL/6J × ♂RR/Sgn) × ♂RR/Sgn (BRR mice). In the present study, QTL mapping analysis was performed for the same trait in the female backcross progeny of ♀(♀RR/Sgn × ♂C57BL/6J) × ♂RR/Sgn (RBR mice), and Lsq1 was identified again. As litter size is significantly larger in BRR mice than that in RBR mice, the potential effect of grandparental cross direction was indicated. QTL mapping analysis of combined data from BRR and RBR mice showed that Lsq1 was split into two loci: Lsq1-1 and Lsq1-2. The RR/Sgn strain-derived allele was associated with reduced litter size at both loci. Lsq1-1 and Lsq1-2 exhibited significant effects on the number of stillbirths in RBR mice but not in BRR mice, and the RR/Sgn strain-derived allele was associated with increased stillbirths at both loci. Therefore, the effects of Lsq1-1 and Lsq1-2 suggest that the number of stillbirths depends on the grandparental cross direction and that the smaller litter size in RBR mice is a consequence of increased stillbirths. Lsq1-1 and Lsq1-2 are suggested to be novel QTL associated with murine litter size.
This study investigated the reproductive cycle of the edible oyster, Crassostrea belcheri, harvested originally from creeks near Pedaing village in the southern part of Myanmar in September 2017-October 2018 through histological analysis. Five maturity stages were detected in the C. belcheri gonads: indifferent, developing, mature, spawning, and spent. The overall sex ratio of males to females of 1:0.98 showed no statistically significant difference from the expected sex ratio of 1:1 in any month. Hermaphrodites could not be observed in 250 oysters. Moreover, the quantitative monthly gonad index values varied from 1.5 in November and June to 2.75 in March. Histological analysis of C. belcheri revealed that mature male and female gonads were detected in almost all months, except in November-December 2017 and June 2018. Spawning occurred throughout the study period, except in January-March 2018, peaking at the beginning and end of the dry season in October-November and April-May, respectively.