Citrus is a complex source of carotenoids with the largest number of carotenoids found in any fruit. Carotenoid concentration and composition vary greatly among citrus varieties. Satsuma mandarin (Citrus unshiu Marc.) predominantly accumulates β-cryptoxanthin in the juice sacs. Valencia orange (Citrus sinensis Osbeck) predominantly accumulates violaxanthin isomers in the juice sacs. Lisbon lemon (Citrus limon Burm.f.) accumulates low level of carotenoids in the juice sacs. To elucidate the carotenoid accumulation in citrus fruit maturation, the expression of genes related to carotenoid biosynthesis and catabolism was investigated in the three citrus varieties exhibited different carotenoid profile. The results showed that the carotenoid accumulation during citrus fruit maturation is highly regulated by the coordination of the expression for the genes related to carotenoid biosynthesis and catabolism in both flavedo and juice sacs. ‘Tamami’ is a hybrid between ‘Kiyomi’ tangor (Citrus unshiu Marc. × Citrus sinensis Osbeck) and ‘Wilking’ mandarin (Citrus nobilis Lour. × Citrus deliciosa Ten.). To elucidate the mechanism of the accumulation of β-cryptoxanthin in ‘Tamami’, a variety accumulating higher β-cryptoxanthin than Satsuma mandarin, the expression of genes related to carotenoid biosynthesis and catabolism was investigated in the juice sacs of ‘Tamami’. The results showed that the mechanism of β-cryptoxanthin accumulation in ‘Tamami’ was similar to that in Satsuma mandarin. Furthermore, in the recent studies, possible factors, which regulate carotenoid concentration and composition in citrus juice sacs were investigated in vitro.

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To understand the anatomical features and fertilization processes of female flowers in Japanese chestnut, we examined the differentiation of transmitting tissue. From the observation of serial transverse sections from the base of the ovary to the style, it was revealed that nine septa formed nine styles. The transmitting tissue in the style appeared in the boundary area where the two adjacent septa joined. The epidermal cells of each style were derived from the cortex parenchyma surrounding the transmitting tissue, and each style elongated cylindrically during flower development. The transmitting tissue, a solid type, was observed at the top of the stigma. Ovules with a short, thick funiculus were pendulous on the surface of the placenta under the style, and were anatropous. The interval between the terminal of the transmitting tissue and the top of the ovary contained no track for pollen tubes to migrate along. This interval might be important for pollen tube growth.

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Bud dormancy in temperate woody perennials is a complex process consisting of three different stages; paradormancy, endodormancy, and ecodormancy. Endodormant buds differ from the other types of dormant buds in that they cannot resume growth under favorable conditions. Because endodormant buds require a certain amount of chilling accumulation for the transition to ecodormancy, genes showing chilling-mediated differential expression patterns are candidates for internal factors controlling endodormancy. To search for genes controlling the endodormancy of Japanese apricot (Prunus mume Sieb. et Zucc.), we performed 454-pyrosequencing to examine gene expression patterns of the dormant leaf and flower buds of Japanese apricot at three different stages of dormancy. We also used buds from branches that had been collected at the endodormant stage and treated with cold or non-cold temperatures. From 485,376 reads generated, we obtained 28,382 contigs and 85,247 singletons, of which 47,401 (41.7%) were annotated by BLAST searches against the non-redundant NCBI protein/nucleotide database. Among them, only 2,530 sequences showed high sequence similarity to Prunus genes in the database, while the remaining 44,871 sequences showed similarity to known genes of other genera and were novel in Prunus. Functional classification by the gene ontology (GO) term indicated that the genes obtained in this study function in a relatively wide range of biological processes. We searched for up-regulated genes in endodormant leaf and flower buds and found that 74 and 82 genes, respectively, were up-regulated at the endodormant stage as compared with the paradormant stage. About one-third of them, 21 and 25 genes in the leaf and flower buds, respectively, were down-regulated at the ecodormant stage as compared with the endodormant stage. P. mume DORMANCY-ASSOCIATED MADS (PmDAM) genes were among those that were up-regulated preferentially in endodormant buds. From the EST data obtained, we constructed a “Japanese apricot dormant bud EST database” (JADB) for future studies on dormancy in Prunus.

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‘Kyo-temari’, a parthenocarpic tomato cultivar with the pat-2 gene, produces only a few seeds. To elucidate the cause of seed formation restriction in ‘Kyo-temari’, we observed pollen tube elongation and ovule morphology in some parthenocarpic tomatoes. In ‘Renaissance’, a parthenocarpic tomato cultivar with the pat-2 gene, pollen tube elongation was inhibited at the style base; however, in ‘Kyo-temari’, the pollen tubes elongated in the style normally but did not enter the ovules. The percentage of ovules in which a pollen tube entered was 70.4% in ‘Louis 60’, 0.8% in ‘Kyo-temari’, and 5.1% in ‘Renaissance’. From observing transverse sections of ‘Kyo-temari’ ovules, there were many ovules with an abnormal micropyle. Because these anomalous ovules were not observed in ‘Renaissance’, a peculiar factor is considered as the cause of anomalous ovule formation and seed formation restriction in ‘Kyo-temai’.

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Influence of arbuscular mycorrhizal fungi [AMF, Glomus sp. R10 (Gr) and Gigaspora margarita (GM)] and sodium chloride (NaCl) on Fusarium root rot and antioxidative abilities in asparagus (Asparagus officinalis L., ‘Welcome’) plants was investigated. AMF plants accumulated higher dry weight of shoots than non-AMF plants with or without NaCl treatment during 16 weeks after AMF inoculation. Ten weeks after Fusarium oxysporum f. sp. asparagi (Foa, MAFF305556, N9-31, SUF1226, and SUF844) inoculation, the incidence and severity of Fusarium root rot were eased in AMF plants; most of the Gr plants showed lower severity than GM. In this case, a synergetic effect in disease suppression occurred in some of the AMF plants treated with NaCl. As for antioxidative ability, SOD activity of shoots and roots increased in most of the Gr plants in both NaCl- and non-treated plants 10 weeks after Foa inoculation. Gr plants had higher DPPH radical scavenging activity of shoots and roots than non-mycorrhizal plants with or without NaCl, especially 16 weeks after AMF inoculation. Ascorbic acid contents of shoots and roots increased in most of the Gr plants without NaCl treatment both 16 weeks after AMF and 10 weeks after Foa inoculation. From these findings, AMF induced a growth promotion effect and alleviation of Fusarium root rot in asparagus plants, and the synergetic effect of disease suppression could be expected by the combination use of AMF and NaCl. In addition, it supposed that changes in antioxidative ability might be associated with disease reduction in mycorrhizal asparagus plants.

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The inflorescence shape of hydrangeas can be divided into two types, lacecap and mophead (hortensia), according to the position and number of decorative flowers in the inflorescence. We found a mutant that bore a mophead inflorescence in a wild population of H. serrata in the eastern part of Tamba Highlands in Japan on July 6, 1999. This mophead inflorescence was composed of 200 flowers, of which 80% were decorative flowers. Eighty-six other H. serrata plants in the wild population set several decorative flowers only on the periphery of the inflorescence. No plant showed the intermediate phenotype of inflorescence between lacecap and mophead types in the serrata population. These results indicate that the occurrence of the mophead phenotype in lacecap populations is not through the process of a step-by-step increase in the numbers of decorative flowers and that the mutation of inflorescence type is not a quantitative, but a qualitative change. We investigated the inheritance pattern of inflorescence types of hydrangeas using one lacecap cultivar and two mophead cultivars. All F1 progenies obtained from crosses between lacecap and mophead cultivars bore lacecap inflorescences. Segregation into lacecap and mophead types in F2 progenies fitted the expected ratio of 3 : 1. The crossing test between lacecap and mophead types showed that the segregation of inflorescence types was consistent with Mendelian inheritance and that a single major gene controls inflorescence types. Three sets of original cultivars and their mutants were used for comparisons between inflorescence compositions of lacecap and mophead types in order to elucidate the functions of genes controlling inflorescence type. Total flower numbers of inflorescence and numbers of secondary inflorescences on the axes of the primary inflorescences were reduced with mutation of the inflorescence type from lacecap into mophead. The primary inflorescence axis of the mophead type was longer than that of the lacecap type. Further study will be necessary to clarify if these changes are due to another function of the gene controlling inflorescence types. This study revealed the inheritance pattern of inflorescence types of hydrangeas. This finding will be useful for efficient breeding of hydrangeas.

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White chrysanthemum flowers frequently mutate to yellow, but such mutation is rare in ‘Jimba’. We found a bud sport (BS) of ‘Jimba’ with a faintly yellow flower. By applying heavy-ion-beam radiation to the BS, we obtained mutants with a pale yellow flower (IB-1 lines). We irradiated those and obtained mutants with much deeper yellow flowers (IB-2 lines). Decreased expression of carotenoid cleavage dioxygenase 4 (CmCCD4a) was well correlated with increased carotenoid content in petals of the mutants. CmCCD4a comprises a small gene family in the ‘Jimba’ genome; at least 4 homologs were expressed in the petals of wild-type ‘Jimba’ and BS, but only 3 were expressed in the petals of IB-1 and only 1 in IB-2. We hypothesize that the decreased number of CmCCD4a homologs caused by irradiation is responsible for the decrease in expression.

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Flavonoid pigments and flower colors of the violet and purple flower cultivars ‘Royal Violet’ and ‘Royal Red’, respectively, of Aubrieta × cultorum in the family Brassicaceae were investigated. Three acylated cyanidin 3-sambubioside-5-glucosides (1–3) were isolated as the main anthocyanins from violet and purple flowers of both cultivars. In particular, 1 was the dominant anthocyanin in both cultivars. Furthermore, an acylated flavonol glycoside (4) and another acylated flavonol glycoside (5) were isolated as the main flavonol pigments from flowers of ‘Royal Violet’ and ‘Royal Red’, respectively. The structures of 1–5 were elucidated by chemical and spectroscopic methods. Pigments 1, 2, 4, and 5 were found to be new flavonoid pigments. The structures of 1 and 2 were determined to be cyanidin 3-O-[2-O-(β-xylopyranosyl)-6-O-(trans-sinapoyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside] and its demalonyl derivative, respectively. The structures of 4 and 5 were determined to be kaempferol 3-O-[2-O-(β-glucopyranosyl)-6-O-(trans-sinapoyl)-β-glucopyranoside]-7-O-[4-O-(β-glucopyranosyl)-6-O-(trans-sinapoyl)-β-glucopyranoside] and its desinapoyl-cellobiosyl derivative, respectively. Pigment 3 was identified to be the known compound cyanidin 3-O-[2-O-(β-xylopyranosyl)-6-O-(trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside]. The flower color of ‘Royal Violet’ was Violet 87A and that of ‘Royal Red’ was Purple 78A according to the R.H.S. Color Chart. On the visible absorption spectral curve, fresh petals and pressed petal juices of ‘Royal Violet’ in pH 5.0 buffer solution showed two characteristic absorption maxima at 560 and 604 nm and those of ‘Royal Red’ showed a single broad absorption maximum near 546 nm. In the reproducible experiments of their flower colors in pH 5.0 buffer solution, the violet solution was produced by the mixture of 1 and 4 (1 : 2) and exhibited characteristic absorption maxima at 560 and 604 nm, similar to those of the flower of ‘Royal Violet’. In contrast, a mixture of 1 and 5 or that of 1 and other common copigments produced a purple solution with only one absorption maximum near 547 nm. From these results, it was revealed that 4 was more appropriate for the bluing effect of A. × cultorum cultivars by intermolecular copigmentation with 1 than 5.

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Cultivars resistant to chrysanthemum stunt viroid (CSVd) are desirable for stable production of chrysanthemum (Chrysanthemum × morifolium Ramat.). We previously reported that CSVd was absent not only from shoot apical meristems (SAMs) but also from leaf primordia (LP) of resistant plants following CSVd inoculation. Using this characteristic as a phenotypic marker, we could identify several resistant cultivars in this study. CSVd was inoculated directly into the SAMs of 85 commercial cultivars by attaching SAMs to infected root tips in vitro, and the cultivars were tested for the presence of CSVd in newly expanded leaves. Of the 85 cultivars, 20 resistant candidates could be identified. These plants were classified into two types according to their CSVd infection characteristics: a CSVd-uninfected or slow titer-increasing type and a CSVd-disappearance type. Scions of four of the 20 candidate cultivars were grafted to CSVd-infected rootstocks for evaluation of the CSVd titer in newly expanded leaves. Although CSVd was detected at high titer in two candidate cultivars over the two-month testing period, ‘Sei no Issei’ and ‘Mari Kazaguruma’, other two candidate cultivars, proved to be resistant cultivars. In ‘Sei no Issei’, CSVd was detected temporarily after grafting, but titers decreased in the newly expanded leaves, while CSVd was not detected in a shoot tip of an infected plant and only at trace levels in a young leaf. ‘Mari Kazaguruma’ also proved to be a resistant cultivar with a slow titer increase. The different types of CSVd resistance in chrysanthemum cultivars will contribute to CSVd-resistant breeding. With some modifications, the in vitro screening method established here will be available for broadening the diversity of genetic resources resistant to CSVd.

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The exercise intensity of three different horticulture activities (propagating herbs, transplanting, and making a vegetable garden) in older adults was determined. Seventeen older Korean adults (mean age 66.9 ± 2.7 years, body mass index 26.8 ± 3.4) that met the inclusion criteria (over 65 years in age, no uncontrolled chronic diseases, no heart and lung diseases, no pacemaker, and nonsmoking) participated in the study. The subjects visited the Konkuk University campus, Seoul, South Korea two times to complete the horticulture activities during June 2011. Propagating herbs and transplanting were completed in a glasshouse during the first visit, with each activity taking about 20 min. The third activity involved making a vegetable garden and required an average of 25 min during the second visit. Metabolic and heart rates during each activity were determined using a portable calorimetric instrument with a radiotelemetry monitor. Propagating herbs and transplanting were determined to be low intensity physical activities (2.4 ± 0.5 metabolic equivalents (METs) and 2.7 ± 0.5 METs, respectively) while making a vegetable garden was a moderate intensity physical activity (3.7 ± 0.7 METs) for older adults.

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