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991.
992.
A water and dye-free heat treatment method was used to color wool fibers. The heat effect changed wool fibers to different colors from white in a nitrogen atmosphere. The influences of heating temperature and time on the colors of wool were investigated and the mechanical property of colored wool fibers was evaluated. The color strength of wool fibers increased as heat treatment temperature and time increased. The tensile strength retention rate of wool fiber was relatively high (≥90 %) when the heat temperature was below 200 °C. The surface morphologies of wool fibers scarcely changed during the heat treatment. The carbon content of fibers was found to reduce by heat treatment, indicating oxidization of components in the wool fibers in the process of coloration. Heat treatment may provide a water and dye-free approach to color wool and other textile fibers, albeit within a limited color range. 相似文献
993.
Junzeng Xu Yuping Lv Likun Ai Shihong Yang Yupu He Twecan Dalson 《Paddy and Water Environment》2017,15(2):381-393
Based on data collected from rice fields under drying–wetting cycle condition, the procedure of dual-crop coefficient (K cd) approaches was calibrated and validated to reveal its feasibility and improve its performance in rice evapotranspiration (ET c) estimation. It was found that K cd based on FAO-recommended basal crop coefficients (K cb) underestimated dual-crop coefficients in monsoon climate region in East China. The recommended coefficient (K cp) value of 1.2 was not high enough to reflect the pulse increase of rice ET c after soil wetting. The K cb values were calibrated as 1.52 and 0.63 in midseason and late season, and the K cp value was adjusted as 1.29 after soil wetting in rice field under drying–wetting cycle condition. The dual-crop coefficient curves based on locally calibrated K cbCal and K cpCor matched well with the measured crop coefficients and performed well in calculating rice evapotranspiration from paddy fields under drying–wetting cycle condition. So it can be concluded that the procedure of dual-crop coefficient method is feasible in rice ET c estimation, and locally calibrated K cb and K cp can improve its performance remarkably. 相似文献
994.
Ting Zou Qiao Xiao Wenjie Li Tao Luo Guoqiang Yuan Zhiyuan He Mingxing Liu Qiao Li Peizhou Xu Jun Zhu Yueyang Liang Qiming Deng Shiquan Wang Aiping Zheng Lingxia Wang Ping Li Shuangcheng Li 《Rice》2017,10(1):53
Background
Male fertility is crucial for rice yield, and the improvement of rice yield requires hybrid production that depends on male sterile lines. Although recent studies have revealed several important genes in male reproductive development, our understanding of the mechanisms of rice pollen development remains unclear.Results
We identified a rice mutant oslap6 with complete male sterile phenotype caused by defects in pollen exine formation. By using the MutMap method, we found that a single nucleotide polymorphism (SNP) variation located in the second exon of OsLAP6/OsPKS1 was responsible for the mutant phenotype. OsLAP6/OsPKS1 is an orthologous gene of Arabidopsis PKSA/LAP6, which functions in sporopollenin metabolism. Several other loss-of-function mutants of OsLAP6/OsPKS1 generated by the CRISPR/Cas9 genomic editing tool also exhibited the same phenotype of male sterility. Our cellular analysis suggested that OsLAP6/OsPKS1 might regulate pollen exine formation by affecting bacula elongation. Expression examination indicated that OsLAP6/OsPKS1 is specifically expressed in tapetum, and its product is localized to the endoplasmic reticulum (ER). Protein sequence analysis indicated that OsLAP6/OsPKS1 is conserved in land plants.Conclusions
OsLAP6/OsPKS1 is a critical molecular switch for rice male fertility by participating in a conserved sporopollenin precursor biosynthetic pathway in land plants. Manipulation of OsLAP6/OsPKS1 has potential for application in hybrid rice breeding.995.
996.
Aye Nyein Chan Shutu Xu YaQin Shi YaNan Li Ali Farhan DongWei Guo JiQuan Xue 《Euphytica》2017,213(1):12
Association mapping was conducted to explore favorable alleles of the chlorophyll-related non-yellow coloring 1 (NYC1) gene under light and dark using an association panel of 146 maize inbred lines. A total of 14 polymorphic sites were identified to be significantly associated with at least one of the chlorophyll-related traits at the seedling stage. Four single nucleotide polymorphisms (SNPs) (S320, S2951, S3901, and S3355) from the NYC1 gene were respectively strongly associated with chlorophyll b (chlb), the ratio of chlorophyll a to chlorophyll b (chl_ratio), chlorophyll a degradation (chla_deg), and total chlorophyll degradation (total_chl_deg). SNPs S320 (C/A) in exon 1, and S2951 (A/G) in intron 8 was related to chlb, with 6.01 and 8.89% of phenotypic variation under light treatment, respectively. Under dark treatment, SNP S3901 (C/T), located in 3′ untranslated region (3′UTR), was associated with chl_ratio, explaining 7.01% of the observed phenotypic variation, whereas SNP S3355 (C/G) in intron 9 explained 6.48 and 5.18% of phenotypic variations in chla_deg and total_chl_deg, respectively. Taken together, these results indicated that the NYC1 gene plays an important role in chlorophyll content and other related traits, and different sites act on chlorophyll metabolism under different light intensities in maize seedlings. Furthermore, these findings improve our understanding of the genetic basis of chlorophyll metabolism under different light conditions. 相似文献
997.
The Flowering Locus T (FT)-like genes of angiosperms are highly conserved. The FT-encoded proteins include a phosphatidylethanolamine-binding domain that is involved in the control of the shoot apical meristem identity and flowering time. In the present study, FT genes were investigated in 20 bamboo species that are grouped into sympodial, mixed and scattered bamboos based on their morphology. All examined orthologous FT genes consisted of four exons and three introns. Their encoded protein sequences contained the critical amino acid residues Tyr85, Glu109, Leu128, Tyr134, Trp138, Arg139, Gln140 and Asn152, of which each possesses a biological function. The DNA sequences were rich in single nucleotide polymorphism (SNP) sites. The SNP frequency was 1 SNP/16.8 bp, and the nucleotide diversity (π) equaled 0.265. Some SNPs altered restriction enzyme sites or resulted in changes in amino acid contents. The correlation analysis showed that several SNPs were informative in relation to the underground rhizome types of bamboos. Therefore, FT polymorphisms could be used as a tool to identify the underground rhizome types of bamboos. The phylogenetic tree constructed based on the FT gene sequences showed that the obtained clustering was consistent with the underground rhizome types. The SNP markers developed in the present study will provide information on the genetic diversity of bamboos and they can aid taxonomic study as well. 相似文献
998.
999.
以紫山药为试材,以0.5%柠檬酸水溶液为溶剂,采用超声结合酶法提取花青素,通过单因素试验和正交实验对紫山药中花青素的提取工艺进行优化,并用大孔吸附树脂纯化,对其进行体外抗氧化试验,研究了超声结合酶法提取紫山药花青素最佳工艺参数和其体外抗氧化活性,为紫山药的综合开发利用提供参考依据。结果表明:最佳工艺条件为加酶量1.5%、料液比1∶20g·mL~(-1)、提取时间25min、超声功率200 W。在此条件下,花青素得率为5.91mg·g~(-1)。体外抗氧化试验中,紫山药花青素表现出明显的抗氧化能力,对DPPH自由基(DPPH·)和羟基自由基(·OH)的清除能力明显强于维生素C。 相似文献
1000.