• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.146-146
• /
• 2017

The pod shattering or dehiscence is essential for the propagation of pod-bearing plant species in the wild, but it causes significant yield losses during harvest of domesticated crop plants. Identifying novel molecular makers, which are linked to seed-shattering genes, is needed to employ the molecular marker-assisted selection for efficiently developing shattering-resistant soybean varieties. In this study, a genetic linkage map was constructed using 115 recombinant inbred lines (RILs) developed from crosses between the pod shattering susceptible variety, Keunol, and resistant variety, Sinpaldal. A 180 K Axiom(R) SoyaSNPs data and pod shattering data from two environments in 2001 and 2015 were used to identify quantitative trait loci (QTL) for pod shattering. A major QTL was identified between two flanking single nucleotide polymorphism (SNP) markers, AX-90320801 and AX-90306327 on chromosome 16 with 1.3 cM interval, 857 kb of physical range. In sequence, genotype distribution analysis was conducted using extreme phenotype RILs. This could narrow down the QTL down to 153 kb on the physical map and was designated as qPDH1-KS with 6 annotated gene models. All exons within qPDH1-KS were sequenced and the 6 polymorphic SNPs affecting the amino acid sequence were identified. To develop universally available molecular markers, 38 Korean soybean cultivars were investigated by the association study using the 6 identified SNPs. Only two SNPswere strongly associated with the pod shattering. These two identified SNPs will help to identify the pod shattering responsible gene and to develop pod shattering-resistant soybean plants using marker-assisted selection.

• Korean Journal of Plant Resources
• /
• v.15 no.2
• /
• pp.107-113
• /
• 2002

This study was performed to obtain the information on fruit set, propagation and flowering habits of the exotic ornamental bottle brush tree (Callistemon citrinus). Trees have fruit capsules for four years since the fruit set and they have enlarged for three years. While 2 and 3-year-old capsules have similar seeds in number and size, 1-year-old ones have fewer and smaller seeds. Most dried capsules open when they have 75％ relative water contents. Two year old seeds which they were dried at 30％ germinated better than others. Removal of capsule bearing twigs resulted in greatly increased subsequent flower numbers (an average of 14 flowers per tree) compared with twigs where seed capsule were allowed to remain. In cutting for propagation, semi-hard wood branches dipped in 100mgι$^{-1}$ IBA for 24 hours rooted at 86.4 ％ and had an average of 12.6 primary roots.

• Journal of Ginseng Research
• /
• v.7 no.2
• /
• pp.172-192
• /
• 1983

Light environment and growth of Panax ginseng In habitat and cultivation under natural shade were renewed. Grower's experiences on ginseng stand In relation to light environment were assessed. Change of shading method and grower's concepts on light requirement of ginseng plant in Korea, Manchuria and Japan was counted. Growth of wild ginseng was better under rich light. Optimum crown density index appeared to be 0.7 In natural habitat and 0.4 to 0.7 for the cultivation in forest. Change of light Intensity in forest was greatest in May and reached near to constant value (from 40% to 3% for broad leaf deciduous forest and loom 4% to 2% for pine forest). Insufficient light condition induced long and thin stem, poor flowering and seed bearing, and sequent dormancy. Relation between light and ginseng strand was not clear but light Interception with cool weather was effective. Topography and orientation of bed have been deeply considered for light environment. Panel or bark of won were used for shading in deep forest manly In Manchuria while reed blind and straw thatch were used in Korea. Kinds and number of shades material and seasonal or daily schedule have been simplified probably by labor pressure due to eulargement of plantation. Post height has been greater while width of roof, bed and ditch has changed lisle. Scientific survey in the past omitted important light control methods (complete light hardening etc) which has been practiced in specific areas. The concept and technique of light control in the past in Korea were delicate and intensive including the control of temperature and moisture. For the application of old concept in modem cultivation precise Investigation of the technique including the measurement of light, temperature and moisture is needed.

• Korean Journal of Plant Resources
• /
• v.16 no.2
• /
• pp.123-129
• /
• 2003

This study was conducted to determine the germination characteristics, oil contents and fatty acid compositions of the different safflower accessions. The safflower accessions had nearly the same germination period of about 12-13 days and the germination rate was more than 87.5%. Plant height grew until 84 days after seeding. The number of leaves did not increase after 70 days from seeding. The accessions had a difference of six loaves from 17 to 23 loaves. Flowering time had a difference of 11 days from 79 days after planting to 90 days after planting. The Jangsung accession had the shortest flowering time of 79 days after planting. In the characteristics of bearing fruit, the number of branches including main stem are from 4.7 to 8.8. The number of head flowers had nearly the same number of branches which were 4.8-8.9, numbers of seed per head flower were 29.3-49.1 and the weight of 100 seeds were 2.9-3.9 g. The crude fat content was 21.8-33.9％ and fatty acid content was 66.6-77.6% containing mostly linolenic acid. Oeic acid content was 9.2-16.5% and it contained palmitic acid, stearic acid, venin acid, arachidonic acid etc. Results of this study, the accession Jangsung, which had the shortest flowering time and had the most crude fat content, was observed to be the best accession for the breeding of safflower.

• Korean Journal of Environmental Agriculture
• /
• v.22 no.4
• /
• pp.294-299
• /
• 2003

The seeds of naturally growing Heteropappus hispidus (Thunb.) were treated by nine different doses (0, 10, 20, 40, 80, 120, 160, 200, 300, 400 Gy) of gamma rays to investigate their germination rate and to quantity the characteristics of their germinated plants as like as leaf appearance and length, the formation rate of anthocyanin color in stem 30 days after germination, the formation rate of rosette leaf and multi-shoot, the flowering and seed-bearing, and shoot length. The germination rate at least up to 120Gy was not greatly affected but was rapidly decreased at over 160Gy. It seemed that lethal dose ($LD_{50}$) of germination was 160Gy. The leaf appearance and growth was also inhibited, but the formation rate of anthocyanin color in the flower stem was enhanced up to 30% with dose. The rosette plants were observed in plants irradiated with higher than 40Gy. Multi-shoots were developed over 80Gy. For a short shoot length and bundle of thin stem, it was considered that they can be selected as the potential pot flower plants, through genetic fixation. In particular, it was suggested that the formation of anthocyanin color in flower stem, rosette and multi-shoot plants induced by the high dose of gamma rays could be utilized as the morphological markers for the mutant selection of Heteropappus hispidus (Thunb.).

• Korean Journal of Environment and Ecology
• /
• v.33 no.4
• /
• pp.440-446
• /
• 2019

This study examined the growth and fruiting characteristics and the acorns biomass allometric equation of Quercus acuta to provide reference data related to the growth and seed supply during the restoration of evergreen forest in the warm temperate zone in Wando Island, Korea. For the growth survey, we selected and cut three sample trees having a mean diameter at breast height (DBH) to investigate the growth analysis through a stem analysis. We then developed the allometric equation (Y=aX+b) of DBH and tree height growth characteristic (Y) according to the average tree age (X) of sampled trees and estimated the DBH and tree height according to the age of Quercus acuta. For the fruiting survey, we selected and cut three sample trees with full fruit in August when, they are at the early mature fruiting stage, for the analysis. To develop the acorns/tree biomass allometric equation of Quercus acuta, we selected and cut ten sample trees of evenly divided diameters. The acorns biomass allometric equation ($Y=aX^b$) was derived by analyzing the biomass (Y) and the growth characteristics (X), such as the DBH, tree height, crown width, and crown height. The allometric equations of average tree age according to DBH and tree height were Y=0506X-2.064 ($R^2=0.999$) and Y=0.321X+0689 ($R^2=0.992$), respectively. The developed allometric equations estimated that the DBH were 3.0cm, 8.1cm, 13.1cm and 18.2cm while the tree heights were 3.9m, 7.1m, 10.3m, and 13.5m when the tree ages were 10, 20, 30, and 40 years, respectively. The analysis results of fruiting characteristics showed that the length, the diameter, the number of fruits, and the number of acorns per fruiting branch had the statistically significant difference and tended to decrease from the upper part to the lower part of crown downward. The total number of acorns was 1,312 acorns/tree in the upper part, 115 acorns/tree in the middle part, and 5 acorns/tree in the lower part of the crown. The allometric equation for the amount of acorns with DBH as an independent variable was $Y=0.003X^{4.260}$ with the coefficient of determination at 0.896. Although the coefficient of determination of the allometric equation using only DBH as the independent variable was lower than that using DBH and tree height ($D^2H$), it would be more practical to consider only DBH as the independent variable because of measurement errors.