To maintain appropriate tree shapes for Asian pear trees, multi-leader system would be more suitable, which could be obtained from the proper training systems. Controlling apical dominance should be the major factor for tree shape management and this might be modified by branch bending or pruning methods. When the tree shape was managed with Alternate Fan System, too narrower branch angle depressed flower bud formation because of the vigorous shoot growth but too wider angle also decreased that formation because of the numerous water sprouts. The tree with 75 degrees of internally deviated angle performed superior result in fruiting process. Additionally, heading-back pruning could be another for water sprout emerging. For that reason, the severer heading-back pruning stimulated the more water sprout emerging. The proper pruning method could be obtained by considering the relation between main stem width and sum of remained branch width.
Jae-Young Lee*, Yong-Koo Kim and Hee-Seung Park
Hyun-Hee Han*, Yong-Koo Kim and Jae-Young Lee
The nitrogen contents of leaves were the same on the first measurement of 9 May 2003 and the date was immediately prior date to application of different training angles to the one-year-old shoots grown during the previous year. However, the nitrogen content began to be different according to training angles as early as 8 days after the training of one-year-old branches. The 90° branch showed higher nitrogen content on the eighth date from the training application against 120° or non-trained slanting branch. The 90° branch continuously demonstrated larger nitrogen contents on 23 May and 2 June against non-trained branch. While, the 120° branch began to show the tendency of larger nitrogen content compared with slanting branches from 23rd May which was 2 weeks from training, and this difference continued up to 2 June 2003. The chlorophyll (SPAD value) of the leaves trained to 120° and 90° were the same at the time of initial training was applied on 9t May 2003, but a significant reduction of the chlorophyll (SPAD value) was found as early as eighth date from the first training date and this difference was reduced to be the same on the date of 2 weeks after the initial training date, but the chlorophyll (SPAD value) became different again on 2 June 2003. Correlations between chlorophyll contents (SPAD value) and photosynthetic rates influenced by training angles were highly positive in 90° training and in 120-degree training than non-training. Additionally, the correlations between the specific leaf weight and chlorophyll contents (SPAD value) were highly positive in 120° training than in 90° training or non-training.
Hyojin Kim, Ho-Hyun Kim, Jae-Young Lee, Yong-Won Lee, Dong-Chun Shin, Kwang-Jin Kim and Young-Wook Lim
A cohort of sixth grade students at two newly constructed elementary schools in Seoul, South Korea, performed a self-assessment of ocular discomfort symptoms in association with indoor air quality (IAQ) by indoor plant intervention from early June to mid-Oct. 2011. Indoor plant intervention made little difference in air temperature and relative humidity, but stabilized the increasing levels of carbon dioxide. The indoor concentrations of formaldehyde and ethylbenzene showed little difference, but those of toluene and xylene showed a decreasing trend in classrooms with indoor plants. The participants in classrooms without indoor plants exhibited an increase in ocular discomfort symptoms at School A and a decrease in symptoms at School B; those in classrooms with indoor plants demonstrated a decrease in frequency at both schools. The variation of symptom severity did not follow a clear trend. Participants assessed their symptom severity of ocular discomfort with four options from three points for frequent occurrence to zero points for no occurrence. Among participants in classrooms without indoor plants, symptom severity significantly worsened at both schools as the scores increased from 1.96 to 2.17 at School A and from 2.27 to 2.34 at School B; among those in classrooms with indoor plants, symptom severity significantly lessened at School A and slightly worsened at School B as the scores decreased from 2.33 to 1.98 at School A and increased from 2.35 to 2.42 at School B. After spending the experimental duration in classrooms without indoor plants at both schools, 34.8% of participants at School A and 33.3% of participants at School B perceived their symptom severity as having increased. At Schools A and B, indoor plants decreased the frequency of participants experiencing an increase of symptom severity by 13.0% and 9.7%, and increased the frequency of participants reporting decrease of symptom severity by 34.8% and 22.6%.
Kyoung-Shim Cho, Hyun-Ju Kim, Jae-Ho Lee, Jung-Hoon Kang and Young-Sang Lee
Fatty acid is known as a physiologically active compound, and its composition in rice may affect human health in countries where rice is the major diet. The fatty acid composition in brown rice of 120 Korean native cultivars was determined by one-step extraction/methylation method and GC. The average composition of 9 detectable fatty acids in tested rice cultivars were as followings: myristic acid; 0.6%, palmitic acid; 21.2%, stearic acid; 1.8%, oleic acid; 36.5%, linoleic acid; 36.3%, linolenic acid; 1.7%, arachidic acid; 0.5%, behenic acid; 0.4%, and lignoceric acid; 0.9%. Major fatty acids were palmitic, oleic and linoleic acid, which composed around 94%. The rice cultivar with the highest linolenic acid was cv. Jonajo (2.1%), and cvs. Pochoenjangmebye and Sandudo showed the highest composition of palmitic (23.4%) and oleic acid (44.8%), respectively. Cultivar Pochuenjangmebye exhitibed the highest composition of saturated fatty acid (28.1%), while cvs. Sandudo and Modo showed the highest mono-unsaturated (44.8%) and poly-unsaturated (42.4%) fatty acid composition, respectively. The oleic acid showed negative correlation with palmitic and linoleic acid, while positive correlation between behenic and lignoceric acids was observed.
Mark S. Roh, Eunju Cheong, Ik-Young Choi, Eun-Ha Yoo, Jae-Young Kim and Nam Sook Lee
We investigated the interspecific relationships and intraspecific variations in the genus Corylopsis using RAPD and single nucleotide polymorphism (SNP) in the internal transcribed spacer1(ITS1), 5.8S ribosomal RNA gene specific in C. glabrescens Franch. & Sav. Differences in species identification between morphological characteristics and RAPD result were noticed in some accessions. All C. glabrescens, C. coreana Uyeki, and C. glabrescens f. gotoana (Makino) T. Yamanaka accessions clustered in one major group. However, they could be divided into five subgroups that are not related to the geographical origins. For example, C. coreana accessions from Korea were clustered with C. glabrescens from Japan. Although grouping based on SNP data does not agree with that by RAPD markers, it revealed the limitation in identification and classification of the genus due to high intraspecific variations in SNP. At SNP positions 464, 465, 466, 467, and 496, most accessions of C. glabrescens and C. coreana have C, G, A, A, and T, respectively. In both analyses, C. glabrescens, C. coreana, and C. glabrescens f. gotoana Japan are closely related and this suggests that nomenclature for these three species should be discussed. Although ITS1 5.8S ribosomal RNA gene can not be used for identification at a subspecies level of C. glabrescens, it proved to be useful to differentiate C. sinensisfrom C. sinensis var. calvescens. It is suggested to use C. glabrescens f. gotoana or C. glabrescens f. coreana rather than using C. coreana.
Kang Hee Cho, Seo Jun Park, Su Jin Kim, Se Hee Kim, Han Chan Lee, Mi Young Kim and Jae An Chun
Blueberry cultivars have traditionally been identified based on the evaluation of sets of morphological characters; however, distinguishing closely related cultivars remains difficult. In the present study, we developed DNA markers for the genetic fingerprinting of 45 blueberry cultivars, including 31 cultivars introduced from the United States Department of Agriculture. We obtained 210 random amplified of polymorphic DNA (RAPD) markers using 43 different primers. The number of polymorphic bands ranged from three (OPG-10 and OPQ-04) to eight (OPR-16), with an average of five. A cluster analysis performed with the unweighted pair group method using arithmetic averages produced genetic similarity values among the blueberry cultivars ranging from 0.53 to 0.85, with an average similarity of 0.68. A dendrogram clustered the 45 blueberry cultivars into two main clusters, with a similarity value of 0.65. Cluster I consisted of four rabbiteye cultivars (Pink Lemonade, Alapaha, Titan, and Vernon) and the Ashworth northern highbush cultivar. Cluster II consisted of 31 northern highbush cultivars, eight southern highbush blueberry cultivars, and Northland half-highbush blueberry cultivar. Fifty five RAPD fragments selected were sequenced to develop sequence-characterized amplified region (SCAR) markers, resulting in the successful conversion of 16 of 55 fragments into SCAR markers. An amplified polymorphic band has the same size as the RAPD fragment or smaller according to the primer combinations in the 16 SCAR markers. Among these markers, a combination of 11 SCAR markers provided sufficient polymorphisms to distinguish the blueberry cultivars investigated in this study. These newly developed markers could be a fast and reliable tool to identify blueberry cultivars.