• Journal of Forest and Environmental Science
• /
• v.38 no.4
• /
• pp.275-283
• /
• 2022

A study was designed to investigate the pattern of sexual dimorphism in a plantation of Garcinia kola. Twenty trees were randomly selected for the study and have been observed to flower regularly. A total of 100 inflorescence were randomly collected from the crown of each tree and 500 flowers randomly assessed within the period of four (4) flowering seasons. Floral sex assessment was done visually and with a hand magnifying lens; floral morphometric measurements (i.e. pedicel and perianth length and breadth), inflorescence length, and breadth) was taken using a veneer caliper; number of flowers per inflorescence and inflorescence per twig was counted; while, data analysis was conducted on excel using analysis of variance and pairwise t-test comparison. Four floral sexes were identified in the G. kola plantation studied which were unisexual male flowers, unisexual female flowers, cosexual unisexual male flowers, and cosexual hermaphrodite flowers. Three tree sexes were identified viz: inconstant male, invariant female, and cosexual trees. The plantation was significantly sexually dimorphic in floral sex and phenotypic traits (i.e. pedicel and perianth size), and as well as sexually dimorphic in tree sex and reproductive phenotypic traits (i.e. inflorescence size, number of inflorescences per twig, and number of flower bud per inflorescence). The sexual system of the plantation was therefore trioecious with features suggestive of evolving dioecy through the gynodioecious pathway.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.1
• /
• pp.92-97
• /
• 1989

The study has carried out to investigate the possibility of application of the emerged-peduncle at the 2 year -old plant for ginseng breeding. In the 2 and 3 year-old plant, growth habits of aerial parts of plants that had the inflorescence showed higher vigor in leaf length, number of leaves, rate of fruitage and fertility, and roots yield than those of non-inflorescence. Generally, characteristics such as stem diameter, stem length, leaf length and number of leaves showed highly significant positive-correlation with root weight and fruitage. The trends of characteristics of plant that has inflorescence at the 2 year-old plant was shown one-year faster pattern than the plant that has non-inflorescence. As these results, selection of the plants which have inflorescence at the 2 year-old plant will provide valuable aid for ginseng breeding.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.25-25
• /
• 2017

Inflorescence architecture mainly contributes to final grain yield in crops. Sorghum inflorescence is basically composed of one fertile sessile spikelet (SS) and two infertile pedicellate spikelets (PS). To identify regulatory factors involved in the inflorescence architecture, we screened an EMS mutagenesis population from the pedigreed sorghum mutant library. We found inflorescent architecture mutants, named as multi-seed mutants, msd, with gained fertile ability in PS and also an increased number of floral branches. In natural sorghum populations, it is not common that are fertile. A detailed dissection of developmental stages of wild type and msd1 mutant described that the PS in wild type do not have floral organs, including ovary, stigma, filament and anther, while the msd1 mutants generate intact floral organ in the sessile spikelet. We found MSD1 encoded a TCP transcription factor using bulk segregant analysis (BSA) of F2 population, and was a strongly enriched expression during inflorescence developmental stages. We proposed that MSD1 functions to suppress floral organ maintenance at PS during inflorescence development in Sorghum. To explore the regulatory network associated with PS fertility, whole genome expression profiling was performed at 4 different developmental stages in 6 various tissue types between wild type and msd1. Taken together, we demonstrated that MSD1 was involved in the plant hormone and maybe influenced program cell death in PS via the activation of plant hormonal pathway.

• FLOWER RESEARCH JOURNAL
• /
• v.19 no.1
• /
• pp.37-41
• /
• 2011

This experiment was carried out to find an optimum shading level for the growth of root and shoot, and to find the effect of shading level after August on the induction and growth of inflorescence of Phalaenopsis hybrid. The shading levels were 50%, 60%, 70%, 80% and 90% of natural light($1200{\mu}molm^{-2}s^{-1})$. The $CO_2$ uptake, transpiration rate, carbohydrate content, fresh weight and dry weight of Phalaenopsis hybrid were higher at 50-60% level than the others. But, it was diminished when the shading level was increased from 70% to 90%. Inflorescence length, the number of inflorescence and flower per plant all increased under 50-60% shading level and the day needed for the flowering after treatment decreased. Especially, the induction of inflorescence was depressed and flowering is not occurred under 90% during experiment period. These results suggest that the optimal shading level for the growth of Phalaenopsis including inflorescence was founded to be 50-60% in the season of light intensity and amount of sunshine decrease after august.

• Horticultural Science & Technology
• /
• v.35 no.4
• /
• pp.510-522
• /
• 2017

To better understand the morphological variation for Perilla crop in different areas of China, we studied the morphological variation in 87 accessions (84 cultivated var. frutescens and three cultivated var. crispa) from high latitude (Northeast China) and middle latitude (North and Northwest China) areas of China by examining seven quantitative and 10 qualitative characters. Analysis of the morphological variation determined that there was significant morphological differences in five quantitative traits between cultivated var. frutescens and cultivated var. crispa, including effective number of branches (QN2), number of internodes (QN3), number of branches (QN4), length of the largest inflorescence (QN5), and days from germination to flowering (QN7). However, two quantitative traits-plant height and number of florets of the largest inflorescence-did not show any significant differences between cultivated var. frutescens and cultivated var. crispa. In addition, significant differences for six quantitative traits were found between the accessions of cultivated var. frutescens originating from high and middle latitude areas in China, which included QN2, QN3, QN5, number of florets of the largest inflorescence (QN6), and QN7. Principal components analysis (PCA) identified five quantitative characters [plant height (QN1), QN2, QN3, QN4, QN7] and six qualitative characters [fragrance of plant (QL1), color of reverse side of leaf (QL3), degree of pubescence (QL5), color of flower (QL6), shape of leaf (QL7), and hardness of seed (QL10)] that contributed to the positive direction on the first axis. The other quantitative and qualitative characters contributed to the negative direction on the first axis. Most accessions of cultivated var. frutescens and cultivated var. crispa were clearly separated by the first axis. In addition, most accessions of cultivated var. frutescens are from high latitude and middle latitude areas that were clearly separated by the first axis, except for several accessions. The findings from this study will provide useful information towards understanding the morphological variation of Perilla crop according to geographical distribution in high and middle latitude regions of China.

• The Korean Journal of Ecology
• /
• v.19 no.2
• /
• pp.107-123
• /
• 1996

The position effects on the abortion of flowers, fruits, and ovules were examined in relation to the resource limitation hypothesis using a temperate legume species, Vicia cracca. Fifty plants were randomly sampled from a natural population located at the Belmont Conservation Site in Belmont, MA, USA. Due to indeterminant growth and acropetal flowering of this species, the position of flower or fruit on the plant was able to be coded by the combination of architectural levels such as plant half (lower and upper half) and inflorescence half (lower and upper half) within each plant half. Overall, only 17.3% of the flowers on an inflorescence began to develop into fruits, while overall 36.0% of the fruits initiated failed to mature. Consequently, 11.5% of the flowers successfully matured into fruits. The mean flower number per inflorescence differed significantly among plants as well as between plant halves. Although the probability of fruit initiation was higher in the lower halves of both plant and inflorescence than in the upper halves of the latter, fruit abortion rate differed significantly only between plant halves. The overall mean seed set was 33.6%, implying that about two out of six ovules in a fruit matured into seeds. The seed set was independent of both plant identity and architectural level unlike other reproductive characters examined. When the ovule developmental stage was examined on data pooled over all fruits, the proportion of ovules in varying developmental stages decreased in order of early abortion, seed maturation, late abortion, and seed predation (48.4, 34.9, 12.2, and 4.5%, respectively). A within-fruit ovule position was also used as a class variable for the analysis of position effects on ovule development. All architectural levels considered exerted singificant influence over the ovule development. In particular, ovule development was strongly affected by the within-fruit ovule position. Ovules in both extreme ends within a fruit tended to abort early, while those in the middle position were more likely to mature into seeds. The strong position effects detected from the flowering to seed maturation stage were interpreted as an indication of competitive interaction among reproductive characters which are largely constrained by plant architecture.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.26 no.6
• /
• pp.155-164
• /
• 2023

Sedirea japonica is one of the critically endangered species in South Korea mostly due to artificial harms such as illegal collection and habitat destruction. Therefore, artificial propagation through improving germination rate, increasing growth, and controlling flowering is meaningful for the conservation and reintroduction of S. japonica. It is suggested that cytokinins are one of the multi-factors that contribute to plant growth and floral responses. Especially, exogenous cytokinins have been known to induce or promote shoot growth or earlier flowering in orchids. Therefore, it was investigated how the application of 6-benzylaminopurine (BA) influenced the growth and inflorescence of S. japonica. A foliar spray containing BA at 100, 200, 300, and 400 ppm was applied from 1st July to 30th December 2021. Leaf length, leaf length growth rate, leaf width, and width and length ratio were measured as growth-related factors. Visible inflorescence rate, inflorescence length, the number of flowers per inflorescence, and the distance between the stalks were measured as flowering-related factors. Growth-related factors except for leaf growth rate were not affected by BA treatments, while leaf growth rate was significantly increased by 200 ppm of BA treatment. The visible inflorescence rate increased by 200 ppm of BA treatment, and there seems an optimal concentration and threshold of BA treatment. An iterative experiment with more seedlings and measurement factors would be helpful to figure out the effects of exogenous BA treatment on S. japonica, and it can be applied for mass propagation.

• Horticultural Science & Technology
• /
• v.16 no.1
• /
• pp.40-41
• /
• 1998

This experiment was conducted to investigate the effects of growth retardant uniconazole on the growth and flowering of Cymbidium Pine Clash 'Moon Venus' and Cym. Green Sour 'A One'. Reduction in leaf length of both cultivars was proportional to the amount (0-5g) of uniconazole and growth reduction of 'A One' was more remarkable than 'Moon Venus'. The inflorescence length was reduced 18.4% in 'Moon Venus' and 15.3% in 'A One' by 5g treatment of uniconazole. There was no significant difference in flowering time, number of inflorescences and florets and size of lower sepal regardless of uniconazole treatment. It was concluded that uniconazole treatment is effective in reducing the leaf growth of Cymbidium. However, as high concentration (5g) of uniconazole reduced the growth of inflorescence causing low quality, 1g was recommended as useful concentration.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.39 no.5
• /
• pp.426-430
• /
• 1994

To establish the proper size of seedling of A. gigas, different weight of seedlings were used for this study. Agronomic characters including plant height, number of leaf, leaf length, number of inflorescence, fresh weight and rate of bolting of the aerial parts, root length, root diameter, number of lateral root and root weight of the underground parts were determined and correlation coefficients among them were estimated. Growth of A. gigas showed the significant vigor for all the characters of the aerial parts along with increasing of seedling weight, but root weight in yield decreased in proportion to increasing of seedling weight due to lignification of the root tissue. When the smaller seedlings were transplanted, bolting rates decreased to about 16% as compared with the traditional size of seedlings. Correlation coefficients between aerial and root characters in A. gigas were negative, and the characters such as plant height, number of leaf, number of inflorescence and fresh weight per plant showed highly significant correlation with the rate of bolting which is one of the characters having great influence on yield.

• Journal of Korean Society of Forest Science
• /
• v.103 no.2
• /
• pp.153-158
• /
• 2014

To examine the natural regeneration in the natural mixed-broadlived forest, flowering, fruiting, seed-fall, and seed viabilities of Acer ukurunduense Trautv. & C.A. Mey. (AU) were investigated in Mt. Jungwang, Gangwon-do, from 2009 to 2013. The flower of AU consisited many male and bisexual flowers on the raceme (unusual panicle) and the arrangement of two sex morphs are differed for each inflorescence. Flowering dates are differed between sex morph in the same inflorescence. Stamens are stop growing and disappeared after pollinated pistil begin to grow in bisexual flowers, and male flowers have vestial pistil. The flowers of AU might be pollinated by Apis mellifera, Thyris fenestrella seoulensis, Cerambycidae sp., Andrenidae sp. and Ctenophora sp., and had some mechanism to prevent feom self pollination. The number of flower buds per inflorescence is 189 on June 8, and that of young samaras per inflorescence is 41.2 on June 21. At last ripened samaras per inflorescence is reduced 33.4 on September 5. Mean annual seedfall of AU was 6,720 ea/ha (ranged 670~17,930). Rates of sound seeds are highest 43.2%, and those of damaged or decayed seeds are 41.8%,. Those of undeveloped and empty seeds are 10.2% and 4.8%, respectively. Successful regeneration of AU might be in masting year and on the gap sites with proper conditions to germinate and grow. To understand the natural regeneration of the species, Genus Acer, further study on the fruiting habit, pre- and post-dispersal seed viability, and annual variation on these factor should be needed.