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Watermelon (Citrullus lanatus), an economically important and nutritionally rich Cucurbitaceous crop grown worldwide, is severely affected by bacterial fruit blotch (BFB). Development of resistant cultivar is the most eco-friendly, cost-effective, and sustainable way to tackle this disease. This requires wider understanding of the genetics of resistance to BFB. In this study, we identified quantitative trait loci (QTLs) associated with BFB resistance in an F2 mapping population developed from BFB-resistant ‘PI 189225’ (Citrullus amarus) and -susceptible ‘SW 26’ (C. lanatus) genotypes based on the polymorphic markers identified by genotyping by sequencing (GSB). A linkage map covering a total genetic distance of 3377.1 cM was constructed. Two QTLs for BFB resistance, namely, ClBFB10.1 and ClBFB10.2, both located on chromosome 10 explaining 18.84 and 15.41% of the phenotypic variations, respectively, were identified. Two SNP-based high-resolution melting (HRM) markers WmBFB10.1 and WmBFB10.2 having high positive correlation with resistance vs. susceptible alleles were developed. The efficacy of the markers was validated in another F2 population derived from SW34 × PI 189225. The highest phenotypic variation was found in the locus ClBFB10.2, which also contains three putative candidate genes for resistance to BFB. These findings will accelerate the development of BFB-resistant watermelon varieties via molecular breeding.

High temperature is one of the most significant abiotic stresses reducing crop yield and quality by inhibiting plant growth and development. Global warming has recently increased the frequency of heat waves, which negatively impacts agricultural fields. Despite numerous studies on heat stress responses and signal transduction in model plant species, the molecular mechanism underlying thermomorphogenesis in Panax ginseng remains largely unknown. Here, we investigated the high temperature response of ginseng at the phenotypic and molecular levels. Both the primary shoot growth and secondary root growth of ginseng plants were significantly reduced at high temperature. Histological analysis revealed that these decreases in shoot and root growth were caused by decreases in cell elongation and cambium stem cell activity, respectively. Analysis of P. ginseng RNA-seq data revealed that heat-stress-repressed stem and root growth is closely related to changes in photosynthesis, cell wall organization, cell wall loosening, and abscisic acid (ABA) and jasmonic acid (JA) signaling. Reduction in both the light and dark reactions of photosynthesis resulted in defects in starch granule development in the storage parenchymal cells of the main tap root. Thus, by combining bioinformatics and histological analyses, we show that high temperature signaling pathways are integrated with crucial biological processes that repress stem and root growth in ginseng, providing novel insight into the heat stress response mechanism of P. ginseng.

ABSCISIC ACID-INSENSITIVE 3 (ABI3) is one of the essential transcription factors of ABSCISIC ACID (ABA) signaling, functioning in seed germination, early seedling development, and abiotic stress tolerance. A recent study showed that epigenetic repression of ABI3 by brassinosteroid (BR)-activated BRI1 EMS SUPPRESSOR1 (BES1)-TOPLESS (TPL)HISTONE DEACETYLASE 19 (HDA19) repressor complex is a critical event for promoting seed germination and early seedling development. However, other physiological roles of the repression of ABI3 and ABA responses by BES1-mediated BR signaling pathways remain elusive. Here, we show that BES1-mediated suppression of ABI3 promotes floral transition and ABI3 acts as a negative regulator for flowering. Ectopic expression of ABI3 specifically compromised the early flowering phenotype of bes1-D and induced severe late-flowering phenotypes in wild-type Arabidopsis and Solanum lycopersicum plants. Both spatiotemporal expression patterns and global transcriptome analysis of ABI3-overexpressing plants supported the biological roles of ABI3 in the negative regulation of floral transition and reproduction. Finally, we confirmed that the loss of function of ABI3 induced early-flowering phenotypes in both long- and short-day conditions. In conclusion, our data suggest that BES1-mediated regulation of ABI3 is important in the reproductive phase transition of plants.

Korean ginseng (Panax ginseng) has long been cultivated as an important economic medicinal plant. Owing to the seasonal and long-term agricultural cultivation methods of Korean ginseng, they are always vulnerable to various environmental stress conditions. ABSCISIC ACID (ABA) is an essential plant hormone associated with seed development and diverse abiotic stress responses including drought, cold and salinity stress. By modulating ABA responses, plants can regulate their immune responses and growth patterns to increase their ability to tolerate stress. With recent advances in genome sequencing technology, we first reported the functional features of genes related to canonical ABA signaling pathway in P. ginseng genome. Based on the protein sequences and functional genomic analysis of Arabidopsis thaliana, the ABA related genes were successfully identified. Our functional genomic characterizations clearly showed that the ABA signaling related genes consisting the ABA receptor proteins (PgPYLs), kinase family (PgSnRKs) and transcription factors (PgABFs, PgABI3s and PgABI5s) were evolutionary conserved in the P. ginseng genome. We confirmed that overexpressing ABA related genes of P. ginseng completely restored the ABA responses and stress tolerance in ABA defective Arabidopsis mutants. Finally, tissue and age specific spatio-temporal expression patterns of the identified ABArelated genes in P. ginseng tissues were also classified using various available RNA sequencing data. This study provides ABA signal transduction related genes and their functional genomic information related to the growth and development of Korean ginseng. Additionally, the results of this study could be useful in the breeding or artificial selection of ginseng which is resistant to various stresses.

The interplay of plant hormones is one of the essential mechanisms for plant growth and development. A recent study reported that Brassinosteroids (BR) and ABSCISIC ACID (ABA) interact antagonistically in early seedling developments through the BR-mediated epigenetic repression of ABSCISIC ACID-INSENSITIVE 3 (ABI3). However, the other physiological roles of the BR-mediated regulation of ABI3 and ABA responses beyond early seedling developments remain largely unknown. Here, we showed that the activation of BR signaling by high temperatures promotes flowering time through the suppression of ABI3 expressions. Elevated ambient temperature induced early flowering in wild type Col-0 plants, but not in BR-defective bri1-116 mutant plants. Conversely, a hyper BR biosynthetic dwf4-D mutant displayed more sensitive thermomorphic long shoot elongation and early flowering. Both expression patterns and physiological responses supported the biological roles of ABI3 in the regulation of floral transition and reproduction under high temperature conditions. Finally, we confirmed that the lowered expressions of the transcript and protein levels of ABI3 brought on by elevated temperature were correlated with warmth-induced early flowering phenotypes. In conclusion, our data suggest that the BR- and warmthmediated regulation of ABI3 are important in thermomorphic reproductive phase transitions in plants.

식물의 유일한 활성 스테로이드 호르몬인 Brassinosteroid (BR)는 다양한 내재적 또는 외부 신호 전달 경로와의 통합적인 결합을 통해 식물의 생장 및 발달 과정에서 중요한 기능을 하는 것으로 알려져 있다. 최근 식물학 연구들은 종자의 발아와 초기 발달과정에서 BR과 ABA 사이의 필수적인 상호 작용 메커니즘이 존재하고 있음을 보고하고 있다. 하지만 이들 두 호르몬의 중요한 신호전달 상호작용에 대한 분자 메커니즘은 거의 알려지지 않았다. 식물의 초기 발달과정에서 BR에 의해 매개되는 ABA 신호전달과의 기능학적, 생물학적 상호작용 네트워크를 이해하기 위해 Agilent Arabidopsis 4 x 44K 올리고 칩을 사용하여 비교 전사체 분석을 수행하였다. ABA에 반응하지 않는 bes1-D 돌연변이체에서의 ABA 처리에 따른 다양한 유전자의 발현 패턴을 야생형 식물과 비교 분석하였다. 그 결과 발현의 변화가 발생하는 유전자(DEGs) 2,353 개를 확인하였다. GO 분석을 통해 ABA 신호전달 및 대사에 관여하는 유전자들이 BR 신호전달 경로에 의해 하향 조절되는 것으로 확인되었다. 뿐만 아니라, BR 신호전달 경로는 다양한 비생물학적/생물학적 스트레스, 오옥신 및 ROS 등 다양한 신호전달 체계와 밀접하게 연관되어 있음을 확인하였다. 본 연구를 통해 BR 신호전달의 활성화는 ABA 신호전달에 관여하는 다양한 유전자들의 발현을 억제함을 확인하였다. 또한 본 연구는 다양한 신호 경로 사이의 상호 작용이 다양한 환경요인에 대한 식물의 적응 반응에 중요하게 작용할 수 있음을 보여주고 있다.

Emitter wrap-through (EWT) solar cells with an 18.6% cell efficiency were fabricated by etch-back with etch resist, a selective emitter (SE) with reactive ion etching (RIE) and screen printing technologies. The short-circuit current densities ( J sc ) were more than 40 mA/cm 2 , but the cell efficiency was limited by the fill factor ( FF ), which was as low as 73.4%. An electroluminescence (EL) analysis showed that this low value was linked to shunts occurring in the via-holes. The doping profile difference between the wafer surface and the inside of the via-holes was statistically insignificant. However, the thickness of the deposited SiN x passivation layer in the via-holes decreased from the surface to the inner side, allowing the paste to penetrate the junction through the passivation layer and causing shunts during the firing process. By changing to Ag paste for the shallow emitter, changing the firing conditions and performing a process optimization, an efficiency of 19.5% with a FF of 77.6% was achieved using industrial 6-inch. Cz wafers under AM 1.5G.

The most common low-resistance, high-melting-point metallization material in current semiconductor devices is polycide, which is defined as a silicide over doped polycrystalline silicon (poly-Si). Due to its excellent thermal stability and fabrication compatibility, tungsten polycide (WSi x /poly-Si) gate and bit line interconnects are well established in very-large-scale integrated circuit (VLSI) applications. Studies have been reported on the chemical vapor deposition (CVD) of WSi x using SiH 4 and WF 6 or SiH 2 Cl 2 [dichlorosilane (DCS)] and WF 6 chemistries, which are termed the silane-based WSi x (SiH 4 -WSi x ) 1-4 and the DCS-based WSi x (DCS-WSi x ) process, 5-10 respectively. Recent work has shown that DCS-WSi x are of high quality with less particluates, better confirmality of step coverage, and lower fluorine incorporation in comparison with SiH 4 WSi x films. It is known that the higher deposition temperature of DCS-WSi x causes crystallization of the film during deposition to hexagonal close-packed WSi 2 , a low-temperature polymorphism of tungsten silicide (termed hcp-WSi 2 ). 11,12 Following thermal treat

Among various trials on improving energy conversion efficiency of silicone based photo-voltaic cell, laser doping casts promising future. Several research groups are suggesting their own methods for laser doping. Usually, doping laser is injected inside of narrow phosphoric acid jet. The injected beam propagates through the jet and it grooves surface of silicone cell. The laser energy also heats the silicone surface and phosphorous is penetrated through the surface. In this work, we separate the grooving laser and heating laser. The silicone surface was grooved by a pulsed fiber laser. The spot size of the laser was 50 μm. For surface measurement, grooved with of 200 μm was needed. To have the groove width, we scanned the laser several times. SEM image of the grooved surface showed ripple of the surface. The phosphoric acid was sprayed on the grooved surface. A fiber coupled cw diode laser heated the sprayed Si surface. After heating, the Si was washed thoroughly by deionized water. The depth profile of penetrated phosphorous was examined by using SIMS. The profile indicated that phosphorous was penetrated about 50 nm. Four point measurement of surface resistance also indicated successful laser doping.