The relationship between root color and anthocyanin composition was investigated in 43 radishes: 14 Raphanus sativus L. var. longipinnatus L. H. Bailey cultivars and 29 R. sativus L. var. sativus cultivars. The colors of 53 samples which were nonwhite were investigated using the Horticultural Color Chart of The Royal Horticultural Society, London, England (RHS. CC), and classified into three groups based on the color difference meter. The color in group 1 (28 samples) was in the red region of RHS. CC and their hue values (b*/a*) were from 0.10 to 0.25; that in group 2 (2 samples) was in the red-purple region of RHS. CC and their b*/a* were from 0.04 to 0.05; and that in group 3 (22 samples) was in the red and red-purple region of RHS CC and their b*/a* were from −0.28 to −0.02. The aglycone in groups 1 and 2 was pelargonidin, whereas that in group 3 was pelargonidin or cyanidin. The 3 samples including pelargonidin in group 3 were classified as group 3a, and the 19 samples including cyanidin were classified as group 3b. Groups 1, 2, and 3a comprised known acylated pelargonidin 3-sophoroside-5-glucosides as their main anthocyanins, and group 3b comprised known acylated cyanidin 3-sophoroside-5-glucosides as the main anthocyanins.
Diospyros kaki Thunb. ‘Tennou’ is the main cultivar for kaki-shibu in the southern region of Kyoto, Japan; however, the morphological, componential, and physiological characteristics have not been described. In this study, the floral organ and mature leaf morphology, and soluble tannin, sugar, and organic acid content in the fruit of ‘Tennou’ were evaluated comparing with those of ‘Hiratanenashi’. Changes in the flesh firmness, ethylene evolution, and water loss of the fruit collected in the season for kaki-shibu preparation (15 weeks after full bloom) were investigated during storage at room temperature. ‘Tennou’ bore only female flowers. Configuration of the calyces viewed from above the flower was cross-shaped and thin. The mature leaf blade of ‘Tennou’ was small with a long ellipse. ‘Tennou’ fruit was very small and globular; the fresh weight was 37% of that of ‘Hiratanenashi’ at 19 weeks after full bloom. At 15 weeks after full bloom, the soluble tannin content of ‘Tennou’ fruit was 1.8-times higher than that of ‘Hiratanenashi’; the sugar content was lower, but the organic acid content was higher in ‘Tennou’ than ‘Hiratanenashi’. Fruit flesh of ‘Tennou’ at the time of collection was harder than ‘Hiratanenashi’. Although the extent of water loss of ‘Tennou’ fruit during storage was more marked, ethylene evolution from the fruit was lower than in ‘Hiratanenashi’.
‘Jimba’ is the most popular white-flower chrysanthemum cultivar in Japan. However, this cultivar has many lateral buds, and this results in delayed flowering under a low temperature. We have succeeded in the introduction of two new cultivars of chrysanthemum with reduced axillary buds named ‘Aladdin’ and ‘Imagine’ using ion beam irradiation. However, the flowering in these two cultivars was still suppressed under a low temperature. Therefore the objectives of this study were to develop an effective method for obtaining further mutations with ion beam irradiation to develop non-chimeric chrysanthemum mutants possessing excellent flowering and cultivation properties. Many mutants were selected in M1 plants derived from the ion beam re-irradiation of ‘Aladdin’ and B02-1-1. These mutants showed favorable flower characteristics similar to the original ‘Jimba’ cultivar. Further, we succeeded in the introduction of a new cultivar from ‘Aladdin’, named ‘Aladdin 2’, in which both desirable characteristics, few axillary buds and early flowering at a low temperature, were combined. These two traits will contribute to labor and/or energy saving. Furthermore, this novel approach facilitated the mutation-linked induction of genetic changes in other plants, and is being termed ‘Ion Beam Breeding’.
The effects of viral infection on the growth and yield of the cucumber (Cucumis sativus L.) line “Kyuri Ano 4”, with intermediate resistance to Melon yellow spot virus (MYSV), and susceptible cultivars were investigated. The growth of Kyuri Ano 4 plants infected with MYSV was inhibited much less than that of susceptible cultivars. In susceptible cultivars infected with MYSV, the leaves were small and growth of lateral branches was suppressed. The yields of Kyuri Ano 4 inoculated with MYSV were 79 to 88% of those of the healthy controls, and mosaic fruits were not observed. On the other hand, the yields of susceptible cultivars were only 32 to 52% those of the controls, and mosaic fruits were observed. We determined that resistance to MYSV in Kyuri Ano 4 is sufficient for managing spotted wilt caused by MYSV.
Many persimmon (Diospyros kaki thunb.) cultivars are hexaploid (2n = 6x = 90), which bear seeded fruits. In contrast, seedless persimmon cultivars are nonaploid (2n = 9x = 135) such as ‘Hiratanenashi’, which bear astringent fruits only. We developed nonaploid pollination constant non-astringent (PCNA) persimmon cv. ‘Fukuoka K1 Gou’ (TM; Akiou) by embryo culture of imperfect seeds derived from a cross between ‘Fuyu’ and ‘Taishuu’, both of which are hexaploid PCNA cultivars. ‘Fukuoka K1 Gou’ fruit ripens in mid-October to early November, being almost the same as ‘Taishuu’. The soluble solid content of fruit was 19.6 °Brix that was higher than in ‘Fuyu’ and ‘Taishuu’. The fruit weight was 365 g, being heavier than that of ‘Fuyu’ and almost the same as that of ‘Taishuu’. The fruit skin of ‘Fukuoka K1 Gou’ at harvest time was less reddish than that of ‘Fuyu’. Parthenocarpy and stenospermocarpy abilities of ‘Fukuoka K1 Gou’ were low, causing unstable fruit set, especially in young trees. Spraying 200 ppm of the gibberellin on fruit at 10 days after full bloom and flower thinning before anthesis were both effective for improving the fruit set. Moreover, the combination of both treatments improved the fruit set significantly more than individual treatment.
The effects of rooting medium, the position of cutting, and indolebutyric acid (IBA) treatment on the rooting of cuttings were investigated to clarify suitable rooting conditions for cuttings of Elatostema umbellatum Blume var. majus Maxim. The rooting rate of cuttings in Kanuma soil with a particle size of 14 mm was lower than that in rooting medium with a maximum water holding capacity of 50% or more. In top and normal cuttings, rooting and sprouting rates of cuttings were 93 to 100%, respectively. The maximum root length of top cuttings was longer than that of normal cuttings. When the base of cuttings was treated with 25 ppm IBA solution for 60 minutes, the number of roots per cutting was significantly larger than that of non-treated cuttings.
The effects of solution strength and fruit thinning were investigated on strawberries (Fragaria × ananassa Duch. ‘Nyoho’) grown in peat bags in an elevated CO2 environment (800–2,500 ppm in the day time, November 4 to April 7). Three strengths (low-80%, standard-100%, and high-120%) of nutrient solution (N: 8.85, P: 0.85, K: 3.90, Ca: 2.05, Mg: 0.93 mM; half strength of Ohtsuka A solution) were compared in combination with 2 × 2 levels of fruit thinning in primary (11 vs. 7 fruits) and successive lateral (7 vs. 5 fruits) inflorescences. For plants supplied with the 80% solution, nutrient supply was insufficient in November to December, and vegetative growth was less vigorous in December and January. No significant effect of the solution strength was observed on the fruit yield, but the concentration of total soluble solids (TSS) was significantly lower in fruits supplied with the 120% solution compared to the other 2 solutions. In the plants supplied with the 80% solution, nutrient uptake was lower than and almost equal to that in plants supplied with the standard solution, until late January and thereafter, respectively. Thus, the solution strength should be modified to keep the EC value of drainage around 50 mS·m-1. The highest fruit yield but lowest mean fruit weight were obtained in plants thinned to 11/7 fruits (primary and lateral inflorescences), and the highest fruit weight but lowest yield were obtained in those thinned to 7/5 fruits. The decrease in the mean fruit weight was caused by the increase in the number of inferior fruits of each inflorescence and also by competition for photosynthate, as fruit growth in secondary and tertiary inflorescences was significantly retarded in plants of which the primary inflorescence was thinned to 11 fruits than that of 7 fruits. TSS significantly decreased with an increase in the number of fruit left on lateral inflorescences. Thus, intensive fruit thinning was clarified to improve the growth and quality of strawberry fruit.
This study suggests the possibility of a new cultivation method for continuous fruiting in blueberry. The flowering habit, harvest duration, and shoot growth were investigated in three blueberry species grown under high temperature and long-day conditions before endodormancy. Plants were grown in a greenhouse that was regulated at 10–35°C with a 15–16-hour photoperiod from 2nd Nov., 2010 to 14th Mar., 2011. High-chill cultivars, ‘Weymouth’, ‘Bluecrop’, and ‘Spartan’, flowered in June 2011 and could be harvested from August to September. This harvesting time was 2 months later than the natural season. Also, ‘Weymouth’ and ‘Spartan’ flowered on few shoots in October 2010 and could be harvested only in December. These cultivars shed leaves until April 2011. Low-chill cultivars, ‘Emerald’ and ‘Sharpblue’, continued flowering and fruiting from the top to bottom of the shoots. The harvest period of ‘Emerald’ was from December 2010 to July 2011, and that of ‘Sharpblue’ was from February 2010 to July 2011. Other cultivars, ‘Magnolia’, ‘Tifblue’, ‘Homebell’, and ‘Gloria’, flowered in February and March 2011. According to these results, it is possible to extend the harvest period and harvest fruits continuously including the off-season in some low-chill cultivars such as ‘Emerald’ and ‘sharpblue’ under high temperature and long-day conditions before endodormancy.
Effects of mist cooling during flower bud differentiation and the developmental phase on the flowering time and floret formation were investigated in summer-to-autumn flowering-standard type chrysanthemums, in order to avoid flowering delays caused by high temperatures in the Tohoku region. ‘Iwa-no-hakusen’, ‘Seikai’, and ‘Sei-no-nami’ were grown in a plastic greenhouse under a natural day length with or without long-day treatment about 40 days after cutting, and the mist was sprayed during flower bud differentiation and the developmental phase. Mist cooling reduced the air temperature of the plastic greenhouse and plants by about 3°C during spraying. Anthesis of ‘Iwa-no-hakusen’ was promoted by mist cooling without long-day treatment, and break budding was promoted by mist cooling with long-day treatment. Anthesis of ‘Seikai’ was promoted by mist cooling, and markedly affected compared to ‘Iwa-no-hakusen’. However, anthesis of ‘Sei-no-nami’ was not promoted by mist cooling. Mist cooling before flower budding tended to increase the number of involucral bracts in the capitulum of ‘Iwa-no-hakusen’ and decreased the number of florets in ‘Seikai’. In conclusion, in the Tohoku region, mist cooling can be used in ‘Iwa-no-hakusen’ if a marked effect is obtained during flower budding and break budding. In ‘Seikai’, mist cooling can be useful to regulate flowering, but it is not useful for ‘Sei-no-nami’.
Because it has been reported that calyx-end fruit cracking is not likely to occur in fruit with large calyxes in ‘Fuyu’ persimmon, we investigated Forchlorfenuron as a possible plant growth-regulating substance to promote calyx growth. Forchlorfenuron in a 10-ppm solution was sprayed on young shoots of ‘Taishu’ persimmon trees at leafing time. The treatment increased the calyx size significantly, with the calyx width being 1.26 times and the length between the vertices of the calyx being about 1.15 times those of non-treated plants. The percentage of fruit with calyx-end cracking in treated plants (16.1%) was lower than in non-treated plants (46.9%). In addition, the cracking severity was significantly lower in treated than in non-treated plants. The treatment was ineffective for the fruit weight, and slightly retarded fruit skin coloring and sugar accumulation in fruit harvested at the same time as fruit from non-treated plants.
Effects of postharvest treatment with preservatives containing 100 ppm capillin (principal ingredient of the extract) (SK253-100) from Artemisia capillaris Thunb. extract were investigated on the efficiency for reducing rind injury, black button, and shrinkage of medium-late maturing citrus ‘Kiyomi’ (Citrus unshiu Marc. × C. sinensis Osb.), ‘Shiranuhi’ [(Citrus unshiu Marc. × C. sinensis Osb.) × C. reticulate Blanco], and ‘Kawachibankan’ (Citrus kawachiensis hort. ex. Y. Tanaka) fruit. In ‘Kiyomi’, the effects of capillin concentrations (SK253-0, 50, 100, 150) and purified capillin (SK253-100C) were also determined. The ‘Kiyomi’ fruit treated with SK253-100 showed the lowest ethylene evolution, although those of SK253-50 and SK253-150 were also reduced compared to the control. The respiratory rate was also the lowest in the SK253-100-treated fruit. Furthermore, the incidences of both rind injury and fruit shrinkage were also reduced by the treatment. The ethylene evolution and respiration rate of fruit treated with SK253-100C, containing purified capillin without Artemisia capillaris extract, were at similar levels to those of the fruit treated with SK253-100 containing Artemisia capillaris extract, suggesting that the ingredient capillin in the preservatives could affect ethylene biosynthesis and respiration directly or indirectly. In ‘Shiranuhi’, ethylene evolution and the respiratory rate, along with the incidence of rind injury, were also decreased by the treatment with SK253-100. The SK253-100-treated ‘Kawachibankan’ fruit in prolonged storage showed similar reductions in ethylene evolution and the respiratory rate. A lower incidence of black button and enhanced rind color were observed in the SK253-100-treated fruit. These results suggest that SK253-100 treatment was effective for reducing ethylene evolution, respiration, and injury to fruit skin during storage in medium-late maturing citrus.
The rose is a popular cut flower due to its variety of shapes and colors. However, its domestic distribution has recently decreased in Japan. In order to promote the buying of roses, women’s impressions of roses were analyzed. We surveyed women living in the Kanto region and analyzed their impressions using a semantic differential (SD) method. Women aged from 20–40 tended to prefer split-centered and rosette-shaped roses, and women aged 50 and older were fond of split-centered roses with the shape of typical hybrid tea roses. However, consumers with few years of experience of purchasing flowers tended to strongly favor split-centered roses, and others with many years of purchasing experience strongly favored rosette-shaped roses. Analysis with the SD method revealed that women had “western style”, “feminine” and “elegant” impressions of the roses they favored. The impressions of roses significantly varied with age. Women in their twenties felt “mature”, “dignified”, and “heavy”, women in their forties felt “formal”, and women in their sixties felt “youthful”, “cheerful”, and “fresh”. We inferred that the impression of roses differed with flower types; while split-centered roses had a “formal”, “mature”, “dignified”, and “classic” impression, globular-shaped roses were “mature”, and frilled petal roses were “casual”, “youthful”, “cheerful”, and “cute”.