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51.
Somayeh Keypour Hossein Riahi Mohammad Reza Asef Jafar Abdollahzadeh Ali borhani Naser Safaie 《Forest Pathology》2020,50(4)
The genus Ganoderma Karst. has broad‐spectrum usage in biotechnology, medicine and the food industry. The complexity of the morphology within species has led to uncertain identification in the past, but recent advancements in molecular identification methods have provided scientists with the opportunity to better understand the taxonomy of the species. The present study attempts for the first time to elucidate the distinctiveness of the Ganoderma species growing in Iran concerning those elsewhere in the world based on mitochondrial small subunit ribosomal DNA (mtSSU rDNA) and internal transcribed spacer (ITS) sequence data. The results disclosed that the G. lucidum Karst. samples collected in Iran are more similar to the European Ganoderma species than to the Asian (Chinese) one used in this study. 相似文献
52.
Allelopathy is a procedure in which secondary metabolites are produced by plants. Some plants may beneficially or antagonistically affect other plants through allelochemical compounds which may be released directly or indirectly from live or dead parts and cause allelopathic and phytotoxic effects. The aim of the present study was to investigate the allelopathic possibility of ajowan (Carum copticum) extracts in different concentrations on morphological indices (germination and growth) of wheat (Triticum sativum), barley (Hurdeum vulgare), corn (Zea maize S.C 704), and safflower (Carthamus tinctorius L.) seedlings as proceeding crops and to develop a comprehensive formula for measuring the negative and positive effects of allelochemicals on growth indices such as shoot and root length, as well as the germination percentage on donor plants. It was demonstrated that increasing concentrations of ajowan extracts significantly decreased the Allelopathic Index, percent of germination, and other growth related indices of all seedlings. Based on the proposed Allelopathic Index of experimental plants, it was revealed that ajowan has posed a higher risk to corn and barley especially at the early stages of the growing cycle, while safflower and wheat indicated more tolerance to growth inhibition effects of ajowan in rotational sequence. 相似文献
53.
Summary For RFLP mapping of R-genes, determining resistance to specific races of Phytophthora infestans in tetraploid potato, it is necessary to develop well segregating populations at the 2x level. During mapping studies, evidence was obtained that more genetic factor(s) are involved in the expression of R-genes than conventionally believed. Two experiments are described in which such an additional genetic factor was suppressing or enhancing the expression of unknown R
nand R
ifactors. R
nand R
iappeared to be present in the investigated plant material, containing R4 and R10, or in one of the susceptible crossing parents. In a third experiment, the expression and the segregation of the well known R1 gene was influenced by an additional genetic factor. In that case there were indications for a dominant suppressor. This was established by the selection of susceptible plants carrying a RFLP allele of probe GP21 closely linked to R1. In three of the four F1 populations, resulting from crosses between such susceptible plants and susceptible tester plants, resistnat progenies were found. The resistance appeared to be R1-specific. This clearly indicates that in three of the four investigated susceptible plants, the R1 gene was still present but not expressed. 相似文献
54.
Mohammad Wali Salari Patrick Obia Ongom Rima Thapa Henry T. Nguyen Tri D. Vuong Katy Martin Rainey 《Plant Breeding》2021,140(1):110-122
The meal value of Soybean for monogastric animals is determined partly by sucrose, raffinose and stachyose. Of these, sucrose is desirable, while raffinose and stachyose are indigestible, causing flatulence and abdominal discomfort. The objective of this study was to identify quantitative trait loci (QTL) controlling seed sucrose, raffinose, and stachyose in a set of 140 SoyNAM (Nested Association Mapping) recombinant inbred lines (RILs), developed from the cross between lines IA3023 and LD02‐4485. A total of 3,038 SNP markers from the Illumina SoyNAM BeadChip SNP were used to map the QTLs for sucrose and the RFOs, raffinose, and stachyose. Significant genotypic differences (p < .001) among RILs were observed for sucrose, raffinose and stachyose contents across years. A 3038 Illumina SoyNAM BeadChip SNPs identified three QTLs for sucrose, one on chromosome 1, explaining 10% variance and two on chromosome 3 each explaining 22%. Raffinose QTL was detected on chromosome 6, explaining 6% variance. The mapped QTLs were novel and spanned regions harbouring candidate genes with roles in plant growth including seed development. 相似文献
55.
Yuki Midorikawa Tomohito Shimizu Tetsuya Sanda Katsuyuki Hamasaki Shigeki Dan Mohammad Tamrin Bin Mohamad Lal Goshi Kato Motohiko Sano 《Journal of fish diseases》2020,43(5):541-549
Mass mortality due to necrosis signs occurred in hatchery-reared zoea stage larvae of the mud crab Scylla serrata in Okinawa, Japan, and a causative bacterium was isolated. In this study, we identified and characterized the bacterium by genome analysis, biochemical properties and pathogenicity. The bacterium was a Gram-negative, non-motile, long rod, forming yellow colonies on a marine agar plate. It grew at 20–33°C (not at 37°C) and degraded chitin and gelatin. Phylogenetic analysis of the 16S rRNA gene sequence identified the bacterium as Aquimarina hainanensis. Genome sequence data obtained from Illumina MiSeq generated 29 contigs with 3.56 Mbp in total length and a G + C content of 32.5%. The predicted 16 chitinase genes, as putative virulence factors, had certain homologies with those of genus Aquimarina. Experimental infection with the bacterium conducted on larvae of four crustacean species, brine shrimp Artemia franciscana, freshwater shrimp Caridina multidentata, swimming crab Portunus trituberculatus and mud crab S. serrata, revealed that this bacterium was highly virulent to these species. The present study suggests that the bacterium caused mass mortality in mud crab seed production was A. hainanensis and can be widely pathogenic to crustaceans. 相似文献
56.
以塔里木盆地周边地区多种沙尘源地为研究区,通过塔中、肖塘、若羌、策勒四个风沙观测场获取的沙尘暴过程中贴地层风向、风速数据以及风蚀传感器实测的撞击颗粒数等数据计算出各地起沙临界摩擦速度,利用Gillette经典的垂直沙尘通量及Lettau水平沙尘通量公式对若羌、策勒、塔中、肖塘沙尘通量进行了估算,并通过各层实测的梯度风速作为背景值界定出塔里木盆地多种沙源类型沙通量变化比对特征,结果表明:垂直沙尘通量F量级为10-8kg/(m2.s),水平沙尘通量Q量级为10-4 kg/(m.s);风速相同情况下,F若羌最大,策勒次之,塔中、肖塘较小;Q若羌值最大,策勒次之,塔中第三,肖塘最小。垂直沙通量F与风速都表现出较好的线性相关,风速递增,垂直沙通量递增;风速递减,垂直沙通量递减。在风速递增幅度相同条件下,若羌Q值递增幅度最大,策勒次之,塔中、肖塘基本相同。 相似文献
57.
Mohammad Mijanur Rahman Khairiyah Mat Genki Ishigaki Ryo Akashi 《Animal Science Journal》2021,92(1):e13594
Year by year, huge quantities of by-products are generated during the manufacturing process of soybean-based products. Okara is one of the by-products, and it is an insoluble portion of the soybean. It consists of high moisture (8.4–22.9%); on dry matter basis, it contains high metabolizable energy (9.0–14.2 MJ/kg) and other components that include crude protein (20.9–39.1%), crude fiber (12.2–61.3%), crude fat (4.9–21.5%), and ash (3.4–5.3%). Fermentation of okara improves its nutritional quality and reduces its anti-nutrient contents. Due to animals' palatability, okara can be used to replace the soybean meal/concentrate feed partially or completely in ruminant's diet and partially in nonruminant's diet. Okara feeding does not depress the intake, digestibility, growth, milk production, blood metabolic profiles, and meat quality of animals. However, this by-product decays quickly due to its high moisture content, and its heavy weight and sticky nature make it difficult to process and expensive to dry using conventional methods. This paper thoroughly summarizes the utilization of okara as animal feed in the cause of developing a general guideline with favorable levels of inclusion in the diets of animals for its exploitation and valorization. This review will encourage further research to develop eco-friendly and value added feed for animals. 相似文献
58.
研究不同时期斑茅产量及其化学组分的变化。结果表明:斑茅生物质产量在11月达到最高,其后开始下降;整个生长发育过程中茎叶生物质产量比呈现上升趋势;含水量随生长发育的进行显著降低;叶片灰分含量全年最低为5月,从10月份开始显著增加,至12月份达到最高。茎秆灰分含量略低于叶片,全年最低为10月,最高为7月,变化幅度不大。叶片中木质素含量全年由高到低排列顺序为12月11月9月10月7月8月6月;茎秆中木质素含量全年由高到低排列顺序为12月11月9月7月8月10月6月。10月份茎秆含水量低,灰分含量最低,热值较高,结合产量和燃料品质考虑其更适于直接燃烧,而9月份叶片则更加适于作为生物转化的材料。 相似文献
59.
F. Hajiani A. A. Ghareaghaji Ali. A. A. Jeddi S. H. Amirshahi F. Mazaheri 《Fibers and Polymers》2014,15(9):1966-1976
In view of the interest in wicking properties of these flexible structures, analysis of the wicking phenomena in nylon 6.6 nanofiber yarns is carried out by considering the twist rate effects. A novel method is used based on adding a pH-sensitive dye to yarn interstructure and the analysis of color alteration of nanofiber yarn structure, resulting from a shift in pH, during the capillary rise of distilled water. The results show that the addition of pH- sensitive dye has no influence on the average nanofiber diameter and the wicking behavior of yarns. This study shows that in short durations, the kinetic of the capillary rise follows the Lucas-Washburn equation. The Lambertw, a mathematical function, has been incorporated, which helps measure an equivalent structural factor of nanofiber yarns and vertical wicking height at any given time considering the gravitational effects. The statistical results show that the average of equilibrium wicking height and capillary rise rate coefficient tend to decrease with increasing the nanofiber yarn twist, due to the reduction of continuity and size of capillaries. 相似文献
60.