demonstrated that monoecious genotypes could be grown without pollenizers trees. Hence, the field of investigation was extended; detailed observations and investigations were made for specific variation characteristics and blooming data in 2014. Branches of
Qian Bai, Shuchai Su, Zhu Lin, Pingsheng Leng, and Wenhao Wang
Yuto Kitamura, Hisayo Yamane, Akira Yukimori, Hiroyoshi Shimo, Koji Numaguchi, and Ryutaro Tao
Prefecture, where the most popular cultivar, Nanko, usually blooms in the middle of February. However, the timing of the blooming stage varies depending on the year, with differences of up to 1 month. This fluctuation is an important factor affecting the
Xiaojie Zhao, Guihong Bi, Richard L. Harkess, Jac J. Varco, Tongyin Li, and Eugene K. Blythe
), inflorescence stems, rhizomes, and roots. Reblooming or remontant irises (a subclass of I. germanica ) are capable of blooming more than once per growing season. Use of reblooming iris for cut flower production has the potential to make TB iris cut flowers
I. Citadin, M.C.B. Raseira, F.G. Herter, and J. Baptista da Silva
Differences in heat requirements for blooming and leafing were investigated in peach [Prunus persica (L.) Batsch] using artificially chilled excised shoots and potted trees. `Della Nona' and `BR-1' have high heat requirements; `Planalto', `Sunlite', and `Eldorado' are intermediate; and `Precocinho' and `Riograndense' have low heat requirements. Prolonged chilling enhanced leafing more than blooming. Flower and vegetative buds have different heat requirements during ecodormancy.
Craig E. Kallsen and Dan E. Parfitt
full bloom flowering dates for male and female cultivars are shown for 5 years in Table 1 . ‘Tejon’ flowering dates were coincident with the early blooming female ‘Gumdrop’ ( Kallsen and Parfitt, 2017a ) in 2016–18. During the low chill years of 2014
Warner Orozco-Obando* and Hazel Y. Wetzstein
Recently, the release of Hydrangea cultivars with the capacity to produce a second flush of blooms has created a great expectation in the ornamental industry. However, the lack of fundamental information on flower development of big leaf Hydrangea does not allow a descriptive explanation of why re-blooming capacity occurs. The objectives of this study were to characterize the timing and location of flower initiation and development in several H. macrophylla cultivars throughout an annual cycle. Four cultivars were evaluated: 2 exhibiting re-flowering capacity (Penny Mac-PM and Endless Summer-ES) and 2 without (Madame Emile Mouillere-MEM and Nikko Blue-NB). Plants were managed under outdoor nursery conditions and harvested at each of four different time periods. These periods represented key developmental stages: 1) Pre-induction: late summer, after completion of shoot expansion; 2) Post-induction: late fall, following short day and cold temperature exposure; 3) Dormancy: winter, post leaf abscission; and 4) Post-dormancy: early spring, just prior to bud break. At each sampling time, bud location (terminal or lateral) and stem origin (basal, lateral, terminal, or secondary) were established. All buds >;2 mm were dissected under a stereomicroscope and the degree of floral induction was determined. Floral primordial were initiated not only in the terminal buds but also within axillary buds. The degree of induction and development varied according to the stem origin, bud location and cultivar. Cultivars with re-blooming capacity had floral primordial initiated within buds at the first sampling period prior to receiving inductive conditions. This suggests they may have minimal or no photoperiodic/temp requirements for flowering.
D. E. Kester, Paolo Raddi, and R. Asay
Relationships among blooming and leafing dates of parents, offspring, and the chilling requirements of the intervening seed were determined among a group of families of almond (Prunus amygdalus Batsch). Parentoffspring heritabilities for blooming and leafing dates were high. Leafing and blooming dates of individuals and families, although significantly correlated, were more or less independent traits. Seed chilling was a function of both seed and pollen parents and was correlated with mean bloom and leafing of parents. The correlation coefficient between chilling of a seed and the blooming date of the corresponding offspring plant was significant and large when calculated for families and significant, but low, when calculated for individuals. The seed-leafing correlation was significant when the early and late leafing progeny were considered separately.
I-Ling Lai, Chih-Wan Lin, Tsai-Yu Chen, and Wei-Hsin Hu
Begonia montaniformis × Begonia ningmingensis var. bella hybrids have high ornamental potential. Hence, the aim of this study was to determine the optimal conditions for the micropropagation of a Begonia montaniformis × Begonia ningmingensis var. bella F1 progeny by using various concentrations of plant growth regulators (PGRs) and varying light spectra in half-strength Murashige and Skoog (1/2 MS) medium. The results showed that the explant regeneration was optimal when the lamina was incubated in a medium supplemented with 2.0 μM N6-benzylaminopurine and 0.8 μM α-naphthaleneacetic acid (NAA). Under such conditions, 98% of the explants regenerated adventitious shoots after 8 weeks, and 41 buds were produced per explant on average. The mean shoot length was 9.6 mm, and on average, 4.5 shoots per explant were more than 2 mm long. Subsequently, the induced adventitious shoots were transferred into rooting medium consisting of 1/2 MS and various NAA concentrations. After 4 weeks, the shoots subcultured in this medium showed ≈93% root induction and an average of 3.5 adventitious roots per explant. Furthermore, the applied light spectrum significantly influenced shoot regeneration, and optimal results were achieved under an equal distribution of blue, red, and infrared light. The histological sections of shoots regenerated from direct organogenesis were observed through scanning electron microscopy (SEM). Afterward, the rooting adventitious shoots were subcultured in PGR-free medium for 8 weeks. The seedlings were successfully acclimated 4 weeks after being transferred to soil and bloomed after 11 months in a greenhouse. Thus, the PGR composition in micropropagation efficiently shortened the time to blooming from 25 to 16 months.
Ken W. Leonhardt
Daryl C. Joyce and Neville W. Burton
The cut-flower and potted plant industries in Australia have traditionally been based on exotic species. However, native Australian plants have gradually assumed greater importance—particularly in the expanding export trade, but also on local markets. Floriculture is practiced in all Australian states, with the major production areas for exotic cut-flowers (e.g., roses, carnations) and potted plants being close to the state capital cities. The cultivation of native Australian flowers and of South African Proteaceae tends to be somewhat more decentralized.