FT is one of the major floral activator in photoperiod-dependent flowering pathway. To understand the role of FT homologs in flowering time control of short-day plant soybean, we identified ten soybean FT genes and named GmFTs. Phylogenetic analysis revealed that ten GmFT genes were further categorized into three subclades. Gene expression analysis showed that the most GmFT genes are mainly expressed in leaves. The expression of GmFT2a, GmFT2b, GmFT5a, and GmFT6 was strongly induced under the floral inductive short-day condition, but GmFT4 exhibited opposite expression pattern compared to those of GmFT2a, GmFT2b, GmFT5a, and GmFT6. To understand roles of GmFT genes in flowering, we generated Arabidopsis transgenic plant overexpressing GmFT genes. Both 35S:GmFT2a and 35S:GmFT5a transgenic plants showed extremely early flowering. In contrast, overexpression of GmFT4 delayed flowering of transgenic plants compared to wild type Arabidopsis. The results indicated that GmFT2a and GmFT5a might function as floral activators, while GmFT4 has an opposite function in soybean flowering. Moreover, domain swapping approaches between GmFT2a and GmFT4 revealed that the substitution of the segment B region alone, which is located in 4th exon, was sufficient to change the function of GmFT2a to floral repressor and GmFT4 to floral activator. The results suggested that soybean FT homologs have been functionally diversified during evolution and might play different roles in photoperiod-dependent flowering of soybean.

The maize genome is complex with exceeding the levels of intra-specific variation, repetitive DNA content, and allelic content observed between many species. Because of tremendous diversity and variants, maize is considered as a forefront crop development and estimation of molecular markers for agricultural trait in genetics and breeding. Using quantitative trait loci (QTL) and marker assisted breeding (MAS), molecular breeders are able to development of drought tolerance and grain yield in maize genotype. To study QTL congruency, a meta QTL analysis including results from eight-teen QTL publications for grain yield and drought tolerance were considered. Among them, we assembled 420 QTLs for abscisic acid (ABA) concentration, anthesis silking interval (ASI), days to flower, days to silk, ear number, kernel number, grain number and grain yields, involved in drought tolerance and grain yield. The meta QTL analysis revealed significant evidence for linkage of these traits to 39 different segments as candidates regions on maize genome. A total of 571 marker was selected as QTL or integrated QTL markers for narrowing down the QTL region into specific functionally relevant candidates. The results of meta QTL analysis helped to refine the genomic regions of agricultural traits, interest described and provided the closest flanking markers.

Next generation sequencing technologies provide opportunities to reveal the genetic variants and differentially expressedgenes. The genetic variants are closely relevance to understanding of genes and phenotypic differences related to agronomic characteristics among cultivars. In this study, we conducted RNA-seq using two Korean soybean accessions, including Daewon and Hwangkeum, by using next generation sequencing against Williams 82 genome as reference. A number of variants such assingle nucleotide variants (SNV), multiple nucleotide variants (MNV), insertion/deletion (InDel) and replacement, was 34,411 and 55,544 in Daewon and Hwangkeum, respectively. Among these variants, 9,611 nonsynonymous variants were detected within 4,290 genes in Daewon and 13,225 non-synonymous variants were located on 5,672 genes in Hwangkeum. The distribution of nonsynonymous variants and expression values of genes can serve as invaluable resource for genotyping and study of traits within genes for soybean improvements.

본 연구는 폐경 전 성인여성의 일반적특성, 생활습관, 식습관, 여성건강행태 및 신체조성에 따른 대퇴골전체, 대퇴 골경부 및 요추의 골밀도 차이가 존재 하는지 규명하여 골밀도의 영향요인을 분석하였다. 연구는 제4기(2008년∼ 2009년), 제5기(2010년∼2011년)에 실시한 국민건강영양조사 자료를 활용하여 30세 이상 폐경 전 성인여성 3820명 을 대상으로 실시되었으며 이 결과는 폐경 전 성인여성에서 골밀도 영향요인이 무엇인지 규명하여 치료하는데 필요한 권고사항이나 지침을 마련하고, 젊은 성인여성의 골밀도를 올바르게 평가하여 폐경 후 골다공증 예방을 위한 보건교육 자료의 개발을 위한 기초자료를 제공하고자 한다. 폐경 전 성인여성의 일반적 특성 중 연령은 대퇴골전체에서 40∼44세, 요추에서 35∼39세에 골밀도가 높았다. 교 육수준은 고졸에서 골밀도가 높았고, 여성건강행태 중 초경연령이 낮을수록 골밀도가 높았다. 생활 습관은 흡연경험이 없고 걷는 시간 및 운동 빈도가 규칙적일수록 골밀도가 높았고, 식습관은 햄버거와 피자 섭취를 하지 않을 경우 골밀 도가 높았다. 신체조성 중 비만유병여부는 비만일 때 골밀도가 높았고 저체중일 때 골밀도가 낮았다. 복부비만 및 체중 조절경험이 있는 사람이 골밀도가 높았다. 총체지방률, 총지방량 및 총근육량은 제1사 분위(Q1)에서 제4사 분위(Q4) 로 갈수록 골밀도가 높게 나타났다. 이 연구에서는 비만유병여부, 총지방량 및 근육량이 골밀도 간에는 매우 유의적인 상관관계를 보였으며, 젊은 여성 들은 골밀도를 증가시키기 위해 자신의 체형에 맞는 적정한 체중을 유지해야하며 정상적인 BMI를 유지 할 필요가 있 음을 알았다. 골다공증의 예방을 위해서는 성장기부터 규칙적인 운동과 금연 등의 올바른 생활습관과 젊은 시절부터 적절한 체중조절을 통해 최대 골질량에 도달할 수 있도록 노력해야 할 것이다.

The objective of this study was to evaluate the drought tolerance in maize seedling using leaf rolling. Nineteen maize resources, seven Nested Association Mapping parents lines, six Korean commercial cultivars, and six Southeast Asia commercial cultivars, were used to examine drought tolerance. The leaf rolling scores were measured on each leaf in three stress conditions with moderate drought (10%), severe drought (7%), and extreme drought (5%). Generally leaf rolling score of seedlings increased at the lower soil water potentials (5~7%). As a result, drought-tolerant cultivars showed lower leaf rolling score (below 2.5) than the drought sensitive cultivars (above 3.5). Nine varieties, NK4043, CML322, DK9955, NK4300, Ki11, DK8868, CML228, LVN99, and LVN10, have been selected for tolerance to drought stress. These results suggest that the leaf rolling score in maize seedling has been made available to indirect index for drought tolerance.