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211.
J. M. Lenis M. Ellersieck D. G. Blevins D. A. Sleper H. T. Nguyen D. Dunn J. D. Lee J. G. Shannon 《Journal of Agronomy and Crop Science》2011,197(4):302-310
Salinity reduces crop yield by limiting water uptake and causing ion‐specific stress. Soybean [Glycine max (L.) Merr.] is sensitive to soil salinity. However, there is variability among soybean genotypes and wild relatives for salt tolerance, suggesting that genetic improvement may be possible. The objective of this study was to identify differences in salt tolerance based on ion accumulation in leaves, stems and roots among accessions of four Glycine species. Four NaCl treatments, 0, 50, 75 and 100 mm , were imposed on G. max, G. soja, G. tomentella and G. argyrea accessions with different levels of salinity tolerance. Tolerant genotypes had less leaf scorch and a greater capacity to prevent Na+ and Cl? transport from soil solution to stems and leaves than sensitive genotypes. Magnitude of leaf injury per unit increase in leaf Na+ or Cl? concentrations was lower in tolerant than in susceptible accessions. Also, plant injury was associated more with Na+ rather than with Cl? concentration in leaves. Salt‐tolerant accessions had greater leaf chlorophyll‐meter readings than sensitive genotypes at all NaCl concentrations. Glycine argyrea and G. tomentella accessions possessed higher salt tolerance than G. soja and G. max genotypes. 相似文献
212.
213.
Mun Sup Yoon Jeongran Lee Chang Yung Kim Jung Hoon Kang Eun Gi Cho Hyung Jin Baek 《Euphytica》2009,165(1):69-77
Approximately 7,000 accessions of Korean soybean (Glycine max (L.) Merrill) landraces, largely composed of three collections, the Korea Atomic Energy Research Institute’s soybean (KAS),
the Korean Crop Experiment Station’s soybean (KLS) and the Korean Agricultural Development and Technology Center’s soybean
(KADTC) collections, have been conserved at the Rural Development Administration (RDA) genebank in Korea. The accessions within
collections were classified based on their traditional uses such as sauce soybean (SA), sprouted soybean (SP), soybean for
cooking with rice (SCR), and OTHERS. A total of 2,758 accessions of Korean soybean landraces were used to profile and to evaluate
genetic structure using six SSR loci. A total of 110 alleles were revealed by at the six SSR loci. The number of alleles per
SSR locus ranged from 9 to 39 in Satt187 and Satt_074, respectively. The number of alleles ranged from 87 in the KADTC collection
to 96 in the KLS collection, and from 63 in the SCR group to 95 in the SP group. Nei’s average genetic diversity ranged from
0.68 to 0.70 across three collections, and 0.64 to 0.69 across the usage groups. The average between-group differentiation
(G
st) was 0.9 among collections, and 4.1 among the usage groups. The similar average diversity among three collections implies
that the genetic background of the three collections was quite similar or that there were a large number of duplicate accessions
in three collections. The selection from the four groups classified based upon usage may be a useful way to select accessions
for developing a Korean soybean landrace core collection at the RDA genebank. DNA profile information of accessions will provide
indications of redundancies or omissions and aid in managing the soybean collection held at the RDA genebank. The information
on diversity analysis could help to enlarge the genetic diversity of materials in breeding programs and could be used to develop
a core collection. 相似文献
214.
Environmental effects on lutein content and relationship of lutein and other seed components in soybean 总被引:1,自引:0,他引:1
J.-D. Lee J. G. Shannon Y.-S. So D. A. Sleper R. L. Nelson J.-H. Lee M.-G. Choung 《Plant Breeding》2009,128(1):97-100
Lutein is a major carotenoid in soybean [ Glycine max (L.) Merr.] seed, and has been shown to be beneficial for eye health in humans. Development of soybeans high in lutein is a goal of some breeding programmes. Little is known about how different growing environments affect lutein content. The objective of this study was to determine the variation of lutein and its relationship to seed protein, oil and individual fatty acids in soybean seed. Fifteen soybean genotypes were planted at four environments. There was no effect of year and planting date on lutein content in soybean seed. However, genotype × year, genotype × planting date and genotype × year × planting date were significant for lutein content. Although each genotype showed similar response across environments, lutein content varied significantly across the four growing environments in 14 of the 15 genotypes evaluated. Lutein content was not correlated with seed protein or oil and palmitic or stearic acid concentrations. However, lutein was positively correlated with oleic acid content and negatively correlated with linoleic and linolenic acids content. 相似文献
215.
Lee T. Hickey Mark J. Dieters Ian H. DeLacy Olena Y. Kravchuk Daryl J. Mares Phillip M. Banks 《Euphytica》2009,168(3):303-310
Pre-harvest sprouting (PHS) in wheat (Triticum aestivum L.) can be a significant problem, causing deleterious effects on grain quality. However, the adverse impacts of PHS can be
reduced by introgressing genes controlling grain dormancy into white-grained bread wheat. Screening for grain dormancy typically
involves germination testing of harvest-ripe grain grown in a glasshouse or field. However, the more uniform environmental
conditions provided by temperature controlled glasshouses (i.e. controlled environmental conditions—CEC) may provide significant
benefits for the assessment of grain dormancy. In this study, the dormancy phenotype of grain grown under CEC incorporating
an extended photoperiod, was compared with 2 years of data from field grown material. Four dormant double haploid lines (derived
from SW95-50213 and AUS1408) and two locally adapted non-dormant cultivars EGA Gregory and EGA Wills were compared in three
replicated experiments grown under CEC (22 ± 3°C and 24 h photoperiod). The germination response of harvest-ripe grain was
examined to assess the expression of grain dormancy. Two measures of germination, the predicted time to 50% germination (G
50) and a weighted germination index, both clearly differentiated dormant and non-dormant lines grown under CEC. In addition,
levels of grain dormancy were similar to field-grown plants. These results demonstrated that CEC with an extended photoperiod
can be used for rapid and reliable characterisation of grain dormancy in fixed lines of bread wheat. 相似文献
216.
Sang-Bum Park Min Lee Dong-Won Son Sang-Min Lee Jong-In Kim 《Journal of Wood Science》2014,60(1):74-79
Authors established a new manufacturing technology for crack-free carbonized boards by pressing and carbonizing the medium-density fiberboard. Industrialization of new functional carbon materials was performed by investigating the fundamental properties of the carbonized boards. To be used as a construction material, the carbonized board needs to satisfy the fire performance regulation. In this study, the carbonized boards were manufactured from medium-density fiberboard (c-MDF) at different temperatures and then fire performance including flame retardancy and smoke toxicity was analyzed using a cone calorimeter and noxious gas analyzer. The results show that as the carbonization temperature increases, weight loss ratio decreases and flame retardancy increases. In the c-MDF at 800 and 1000 °C, no external damage was observed after combustion. These c-MDFs satisfy the total heat release (standard below 8 MJ/m2) and heat release rate (standard below 200 kW/m2) regulations according to the Building Standard Law of Korea and Japan. In addition, the c-MDFs showed the lower total smoke release (TSR, 0.213 m2/m2) than that of virgin MDF (94.281 m2/m2). The c-MDF at 800 and 1000 °C were, therefore, classified as a class III flame retardancy material and can be used as indoor finishing material. 相似文献
217.
Lee Jang Hoon Anderson Anne J. Kim Young Cheol 《European journal of plant pathology / European Foundation for Plant Pathology》2021,161(4):981-986
European Journal of Plant Pathology - Certain chemical pesticides control plant diseases through induction of systemic resistance mechanisms. In this study, orysastrobin, a “quinone outside... 相似文献
218.
Evaluating the role of seed priming in improving drought tolerance of pigmented and non‐pigmented rice 下载免费PDF全文
This study was conducted to evaluate the influence of seed priming on drought tolerance of pigmented and non‐pigmented rice. Seeds of pigmented (cv. Heug Jinju Byeo) and non‐pigmented (cv. Anjoong) rice were soaked in water (hydropriming) or solution of CaCl2 (osmopriming). Seeds were sown in soil‐filled pots retained at 70 (well‐watered) and 35% (drought) water‐holding capacity. Drought stress caused erratic and poor stand establishment and decreased the growth of both rice types. More decrease in plant height and leaf area under drought stress was noted in pigmented rice, whereas decrease in root length and seedling dry weight, under drought, was more obvious in non‐pigmented rice. Pigmented rice maintained more tissue water and photosynthesis and had more polyphenols, flavonoids and antioxidant activity than non‐pigmented rice. Seed priming was effective in improving stand establishment, growth, polyphenols, flavonoids and antioxidant activity; however, extent of improvement was more in pigmented rice under drought. In conclusion, drought caused erratic germination and suppressed plant growth in both rice types. However, pigmented rice had better drought tolerance owing to uniform emergence, and better physiological and morphological plasticity. Seed priming was quite helpful in improving the performance of both rice types under drought and well‐watered conditions. 相似文献
219.
Han-Yong Kim Jonghan Ko Seungtaek Jeong Jun-Hwan Kim Byunwoo Lee 《Journal of Crop Science and Biotechnology》2017,20(5):417-427
Determining effective measures to alleviate the impact of climate change on crops under various regional environments is one of the most urgent issues facing agriculture. In this study, geographic regions of South Korea for future-adjusted barley cultivation were outlined and the impact of climate change on barley production in the next 100 years was evaluated under two greenhouse gas concentration trajectory scenarios: the representative concentration pathway (RCP) 4.5 and RCP 8.5. To achieve our intended study goals, a geospatial crop simulation modeling (GCSM) scheme was formulated using CERES-barley model of Decision Support System for Agricultural Technology (DSSAT) crop model package version 4.6 to simulate grid-based geospatial crop yields. Two experiments were carried out at an open field to obtain model coefficients for the nation and at temperature gradient field chambers to evaluate the performance of the CERES-barley model under elevated temperature conditions. Suitable cultivation regions for three different types of barley (naked, hooded, and malting) under changing climate were projected to expand to the northern regions under both RCP 8.5 and RCP 4.5. However, they were projected to expand more rapidly under RCP 8.5 than those under RCP 4.5. Projected yields of four barley varieties were increased with a slow phase as year progressed under RCP 4.5 scenario. However, they were rapidly increased under RCP 8.5 scenario. It appears that geospatial variation in barley yield under changing climate can be effectively outlined. Therefore, GCSM system might be useful for determining impacts of climate change on geospatial variations of crops, potentially providing means to impede food insecurity. 相似文献
220.
Chiara De Lucchi Piergiorgio Stevanato Linda Hanson Mitch McGrath Lee Panella Marco De Biaggi Chiara Broccanello Marco Bertaggia Luca Sella Giuseppe Concheri 《Euphytica》2017,213(3):71
Fusarium spp. cause severe damage in many agricultural crops, including sugar beet, with Fusarium oxysporum historically being considered as the most damaging of all species. Sugar beet needs to be protected from this class of soil-borne pathogens in order to ensure an optimal sugar yield in the field. Genetic control of the disease is crucial in managing these pathogens. Identification of single nucleotide polymorphism (SNP) markers linked to resistance can be a powerful tool for the introgression of valuable genes needed to develop Fusarium-resistant varieties. A candidate gene approach was carried out to identify SNP markers linked to putative Fusarium resistance sources in sugar beet. Five resistant analogue genes (RGAs) were screened by means of high resolution melting (HRM) analysis in a set of sugar beet lines, considered as resistant and susceptible to Fusarium oxysporum. HRM polymorphisms were observed in 80% of amplicons. Two HRM polymorphisms were significantly associated with Fusarium resistance (P < 0.05). The amplicons that showed association were sequenced and two SNPs were identified. The association was further validated on 96 susceptible and 96 resistant plants using competitive allele-specific PCR (KASPar) technology. The selected SNPs could be used for marker-assisted breeding of Fusarium resistance in sugar beet. 相似文献