• Journal of Ginseng Research
• /
• v.21 no.2
• /
• pp.85-90
• /
• 1997

This study was carried out to clarify the cause of incompatibility in interspecific hybrid plant between Panax ginseng and p. quinquefolium. The floral structure of F,(p.g. x p.q.) hybrid was normal because the redundant anther was 0.2 mm longer than pistil in Fl hybrid and the size and structure of redundant carpel in F, hybrid were similar to P. ginseng and p. quiquefolium Pollens of $F_1$ hybrid did not germinate on stigma of P-quinquefolium but germinated well on stigma of P. ginseng. Pollen tube was able to penetrate styles completely and seed harvest rate was 16.8% in field. However on stigma of $F_1$ hybrid, Pollen did not germinate when P. ginseng was used as male Parent. In addition, the growth of pollen tube was halted on style and seed was not set when P qlfinquefoEi2a was used as male Parent. These suggest that the inhibitor of pollen germination present on stigma caused $F_1$ hybrid sterility. It took 5 hours for pollen grains to germinate, 12 hours to arrive at in trance of ovule, 16 hours to penetrate micropyles in Panax ginseng.

• Korean Journal of Plant Taxonomy
• /
• v.45 no.4
• /
• pp.380-390
• /
• 2015

The morphological characters were observed in six taxa in the genus Dioscorea of Korea (D. polystachya, D. japonica, D. nipponica, D. quinqueloba, D. tenuipes, and D. dokoro). The underground structure and the formation of bulbil were useful characters for separating sect. Enanatiophyllum from sect. Stenophora. The important characters for discriminating taxonomic entities were as follows: the position of the anther and the shape of the pistil in the microstructural characters, including the protuberance of the base of the petiole, the shape and color of the flower, the shape of the fruit, and the shape of the seed wing. Based on the results, a key to Korean Dioscorea is provided and the distribution of these species in Korea is described.

• Korean Journal of Plant Taxonomy
• /
• v.38 no.1
• /
• pp.69-77
• /
• 2008

We report Vallisneria spinulosa S. Z. Yan (Hydrocharitaceae) as an unrecorded species from the flora of Korea. This aquatic vascular plant occurs in reservoirs, streams, and ditches at Changnyeong, Changwon, and Gimhae which belong to Nakdong river basin. Vallisneria spinulosa is distinguishable from V. natans (Lour.) Hara already known to Korean flora by the presence of turion and hairs at base of stamen, adnation between pistil and staminodia, the number of stamen, and shape of fruit and seed. V. spinulosa is similar to V. desnseserrulata Makino in the viewpoint of distribution (Japan and southern China), but V. spinulosa has three to five epidermal wings on the surface of seed.

• Korean Journal of Agricultural Science
• /
• v.50 no.3
• /
• pp.539-547
• /
• 2023

This study evaluated the impact of rain shelters made of plastic film on spring frost damage and fruit quality in Asian pears ('Niitaka') over two years. In 2021, during the coldest spring days (between 0:00 am and 7:00 am), temperatures dropped to -1.20 - 0.43℃ at 120 cm and -1.33 - 0.57℃ at 200 cm above ground level in the control. Conversely, the rain shelter treatment maintained higher temperatures, -0.40 - 0.87℃ at 120 cm and -0.43 - 0.77℃ at 200 cm. Flower damage was significantly lower in the rain-sheltered group, with incidences of 1.3 and 6.9% at 120 and 200 cm, respectively, compared with 18.1 and 22.6% in the control group. Visual observations verified the prevention of frost adhesion on flower organs in the sheltered group, compared with noticeable pistil death and petal browning in the control group. In 2022, when temperatures remained above 0℃, fruitlet stalk length was 5 - 6 mm longer in the sheltered group. The cumulative impact of rain shelters was evident in the improved fruit quality over the two years. This study suggests resilient cultivation strategies in the face of climate change to reduce frost damage, increase productivity, improve fruit quality, and potentially increase incomes of the farmers.

• Molecules and Cells
• /
• v.39 no.10
• /
• pp.768-775
• /
• 2016

The Arabidopsis female gametophyte contains seven cells with eight haploid nuclei buried within layers of sporophytic tissue. Following double fertilization, the egg and central cells of the gametophyte develop into the embryo and endosperm of the seed, respectively. The epigenetic status of the central cell has long presented an enigma due both to its inaccessibility, and the fascinating epigenome of the endosperm, thought to have been inherited from the central cell following activity of the DEMETER demethylase enzyme, prior to fertilization. Here, we present for the first time, a method to isolate pure populations of Arabidopsis central cell nuclei. Utilizing a protocol designed to isolate leaf mesophyll protoplasts, we systematically optimized each step in order to efficiently separate central cells from the female gametophyte. We use initial manual pistil dissection followed by the derivation of central cell protoplasts, during which process the central cell emerges from the micropylar pole of the embryo sac. Then, we use a modified version of the Isolation of Nuclei TAgged in specific Cell Types (INTACT) protocol to purify central cell nuclei, resulting in a purity of 75-90% and a yield sufficient to undertake downstream molecular analyses. We find that the process is highly dependent on the health of the original plant tissue used, and the efficiency of protoplasting solution infiltration into the gametophyte. By isolating pure central cell populations, we have enabled elucidation of the physiology of this rare cell type, which in the future will provide novel insights into Arabidopsis reproduction.

• Journal of Plant Biotechnology
• /
• v.39 no.3
• /
• pp.212-218
• /
• 2012

Glycosyltransferases are enzymes (EC 2.4) that catalyze the transfer of monosaccharide moieties from activated nucleotide sugar to a glycosyl acceptor molecule which can be a carbohydrate, glycoside, oligosaccharide, or a polysaccharide. In this study, a UDP-glucosyltransferase cDNA was isolated from Brassica rapa using a rapid amplification of cDNA ends (RACE) and subsequently named BrUGT. It has a full-length cDNA of 1,236 bp with 119 bp 5'-untranslated region (UTR), a complete ORF of 834 bp encoding a polypeptide of 277 amino acids (31.19 kDa) and a 3'-UTR of 283 bp. BLASTX analysis hits a catalytic domain of Glycos_transf_1 super family (cl12012) that belongs to the Glycosyltransferases group 1 with tetratricopeptide (TPR) regions located between 165 to 350 bp. Expression analysis showed high mRNA transcripts in pistil, followed by petal, seed and calyx of flower. Moreover, expression analysis of BrUGT in Chinese cabbage seedlings under stresses of cold, salt, PEG, $H_2O_2$, drought and ABA showed elevated mRNA transcript. Furthermore, when BrUGT gene was transformed into rice using pUbi-1 promoter, overexpression was evident among the $T_1$ plants. This study provides insights into the function of BrUGT in plants.

• Journal of Plant Biology
• /
• v.3 no.1
• /
• pp.32-38
• /
• 1960

Since the peculiar virus disease of chinese date tree (Zizyphus jujuba Mill. var. inermis Rehd.) has been noted in South Korea around 1950, 70% to 80% of the economically important trees have been either completely destroyed or infected with the virus, severe damage has been noted, particularly, across the area ranged from middle east to the middle part of Korea, including Seoul area. Yoon-Koock-Byung in 1958 first reported the disease and descirbed it might be caused by a kinds of yellows. But he did not conform in his paper that the disease is pecisely caused by yellows virus. The authors, hereby intend to identify the true cause of the desease of the chinese data tree by studying the external symptoms of the disease and the internal morphological characteristics of the diseaset plant which shows various abnormalities in contrast to the healthy checks. In view of fact that leaves of the infected plants become yellowish in color similar to the peach yellows, aster yellows, it is likely to be identifiable as the common yellows. Furthermore, the abnormal characteristics observed by the authors are as follow: The floral organs such as petals, sepals, stamens, and pistil turn into vegetative leaves, the leaves on heavily infected plant appear as small sized one and also showing as a common witch's broom like symptom. There are also an occuring of numerous advantitious shoots developed from both of stems and roots. The amount of photosynthetic starch grains increases in parenchymatous cells, necrosis takes place in mesophyll, Particularly, Palisade Parenchyma in the leaves of infected plants are distinguished in contrast to the healthy checks. From the symptoms and the present experimetns described above, the authors are believed that the disease of chinese data tree is not caused by the yellows. It appears the disease is rather similar to the symptoms of sandal spike virus which was noted in India early in this centry. But the host plant of standal disease, Santalum albun L. and the insect vector, Jassus indicus Wal., have never been reported in Korean flora and the founa. The termperature and the otehr environmental factors is quite different Korea and India. Thus the authors believe that the peculiar disease must be an endemic new virus origin in Korea and must be called as "shoot cluster disease of chinese date tree."

• Korean Journal of Plant Taxonomy
• /
• v.48 no.3
• /
• pp.185-194
• /
• 2018

A comparative floral morphological study of 19 taxa in Persicaria sect. Cephalophilon with four taxa related to Koenigia was conducted to evaluate the taxonomic implications. The flowers of P. sect. Cephalophilon have (four-)five-lobed tepals; five, six, or eight stamens, and one pistil with two or three styles. The size range of each floral characteristic varies according to the taxa; generally P. humilis, P. glacialis var. glacialis and Koenigia taxa have rather small floral sizes. The connate degrees of the tepal lobes and styles also vary. The tepal epidermis consists of elongated rectangular cells with variation of the anticlinal cell walls (ACWs). Two types of glandular trichomes are found. The peltate glandular trichome (PT) was observed in nearly all of the studied taxa. The PT was consistently distributed on the outer tepal of P. sect. Cephalophilon, while Koenigia taxa and P. glacialis var. glacialis had this type of trichome on both sides of the tepal. P. criopolitana had only long-stalked pilate-glandular trichomes (LT) on the outer tepal. The nectary is distributed on the basal part of the inner tepal, with three possible shapes: dome-like, elongated, and disc-like nectary. The nectaries are always accompanied by elongated or spheroidal papillae. Various combinations of floral characters (e.g., the numbers of stamens and styles, the stigma shape, the nectary shape, ACWs, cuticular striation and the trichome type and distribution) of P. sect. Cephalophilon are useful when attempting to recognize the infrasectional levels of P. sect. Cephalophilon recently proposed. Here, we describe the floral characteristics in detail and discuss the taxonomic significance of the floral characters.

• Korean Journal of Plant Resources
• /
• v.28 no.2
• /
• pp.235-242
• /
• 2015

Morphology and characteristics of floral organ in highbush blueberry cultivars were studied to select suitable cultivars of highbush blueberry for domestic cultivation. The stamen consists an anther and a tape-like hairy filament with well-developed trichomes. When the anther was opened, the wall of anther was not dehiscent, and pollen grains were discharged into two tubes. Pollen was mature tetrad type without being separated after meiosis (Late March). The number of pollen granules per anther was 400~1,300, the germination rate was higher in the cultivars having many pollen grains. Pistil was composed of five carpels and a shipper without separate part. The number of ovules per ovary was 39~67, therefore, the coefficient of ranged from 11.6 to 31.0%. The seed pod formation by combination of ‘Bluejay’ and ‘Sharpblue’ was higher in the cross-pollination than in the self-pollination.

• Journal of Korean Society of Forest Science
• /
• v.100 no.2
• /
• pp.131-135
• /
• 2011

To examine the sex morph, fruiting characteristics and seed viabilities of Acer palmatum var. matsumurae (Koidz.) Makino, the flowers and seed-sets of 101 trees were collected from early April to late October 2010, and floral structure and seed viability were studied. Among investigated 101 trees, 73.3% of trees were protandrous (PA: pollen is shed before stigmas are receptive) and 26.7% were protogynous (PG: stigmas are receptive before pollen is shed). Acer palmatum var. matsumurae has heterodichogamous sexual system. Number of flowers and seed-sets per inflorescence are significantly different between sex morphs, and PA has more flowers and seed-sets per inflorescence than PG. Rates of sound seeds and decayed seeds are significantly different between sex morphs. Rates of sound seeds were 46.4% in PA, but 65.6% in PG. and rates of decayed seeds were 49.6% in PA, but 23.6% in PG. The differences of decayed seeds' rates between sex morphs might be related with the timing of pistil flower blooming and insect pests' outbreak.