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71.
72.
Thanankorn Jaiphong Jun Tominaga Kenta Watanabe Ryuichi Suwa Masami Ueno 《Plant Production Science》2017,20(1):126-135
Sugarcane (Saccharum spp.) is an economical crop in the tropical and subtropical countries. However, because of global climate change, flooding has become problematic, particularly during the rainy season, in Thailand. We investigated the effects of floods on three commercial sugarcane cultivars, namely NiF8, U-thong 6 (UT6), and U-thong 9 (UT9), as well as Erianthus spp. Growth was assessed using a pot experiment in a glasshouse with two treatments: (1) control and (2) 60 d of flooding followed by 30 d of normal conditions. In comparison with control, during prolonged flooding, Erianthus showed greatly decreased CO2 assimilation, whereas NiF8, UT6, and UT9 showed slightly declined CO2 assimilation. Growth in plants subjected to 60 d of flooding was less influenced by floods while sucrose content was not affected except in UT6. During flooding, some roots died, resulting in plants compensating adventitious roots to offset the negative effects of root death and to assist them in maintaining their growth, which appeared from the submerged nodes, with different characteristics for each cultivar. However, 30 d after draining, roots remained damaged, while adventitious roots died, resulting in lesser growth as compared with the control, but it did not significantly affect sucrose content and sugar yield. This study suggests that sugarcane plants need to produce the adventitious roots to compensate their roots’ death during flooding and require time to recover their root system after flooding for obtaining the optimum yield and quality at harvest. 相似文献
73.
为明确新型卵磷脂类桶混助剂“融透”的特性,采用透射电镜和激光粒度分析仪表征了其物理性质,并通过室内生物测定和田间药效试验测定了其在防治稻飞虱中对氟啶虫胺腈的协同增效作用。结果表明,“融透”中含有圆形脂质体,Z平均粒径为129.5 nm。室内生物测定结果表明,“融透”可使氟啶虫胺腈对褐飞虱的毒力增加1.67倍。田间药效试验表明,“融透”可使氟啶虫胺腈对稻飞虱的防效提高9.04%~41.77%;当氟啶虫胺腈减量40%时,添加“融透”的处理对稻飞虱的防效与未添加“融透”的常量组相当。研究结果表明,卵磷脂桶混助剂“融透”可以通过形成脂质体提高药剂的利用率,从而达到增效的作用。 相似文献
74.
为研究减少在番茄茎秆好氧堆肥过程中氮素损失的途径,提高堆肥品质,以粉碎的番茄茎秆为原料,按物料干重分别加入5%的腐殖酸(T1)、氯化钙(T2)和过磷酸钙(T3),同时以不进行任何添加的堆体作为对照(CK),进行45 d的好氧堆肥试验。结果表明:3种添加剂均可降低堆肥过程中的氮素损失,同时减少了NH3的挥发量;堆肥结束时,CK、T1、T2和T3处理的氮素损失率分别为18.04%、15.00%、12.65%和14.05%,累计NH3挥发量为CK(1 648.11 mg/kg)>T1(1 330.35 mg/kg)>T3(995.35 mg/kg)>T2(528.11 mg/kg)。其中,添加氯化钙的处理保氮效果最好,与对照相比,氮素损失率低至12.65%,NH3挥发量减少67.96%;各处理高温期均≥3 d,发芽指数≥80%,表明堆体已经腐熟,无植物毒性。综上,番茄茎秆好氧堆肥中添加氯化钙,对于减少堆肥过程中的氮素损失较为理想。本研究可为番茄茎秆好氧堆肥保氮工艺优化提供理论依据。 相似文献
75.
76.
Kinetic Parameters of Gross N Mineralization of Peat Soils as Related to the Composition of Soil Organic Matter 总被引:1,自引:0,他引:1
Bentio Heru Purwanto Akira Watanabe Jong Foh Shoon Ken-ichi Kakuda Ho Ando 《Soil Science and Plant Nutrition》2005,51(1):109-115
Peat land has been considered as an alternative type of land for agricultural development especially in the tropics. In the present study, the N-supplying capacity, one of the most important soil properties in terms of crop production, of peat soils was examined. Ten peat soil samples were collected from Indonesia, Malaysia, and Japan. Gross N mineralization in the soil samples was estimated using a zero-order model, and kinetic parameters of mineralization were determined using a simple type model. Soil organic matter composition was investigated using 13 C CPMAS NMR. Mineralization potential ( N 0 ), apparent activation energy ( E a ), and mineralization rate constant ( k ) ranged between 571–2,445 mg kg−1 , 281–8,181 J mol−1 , and 0.009–0.020 d−1 , respectively. Although none of the parameters showed a significant correlation with the soil C/N ratio, a negative correlation was observed between the k value and the ratio of the proportion of alkyl C in total C to that of O -alkyl C estimated by 13 C CPMAS NMR. The latter suggested that the k values were higher in the peat soils relatively rich in readily decomposable organic matter including carbohydrates. 相似文献
77.
Chemical characteristics and potential source of fulvic acids leached from the plow layer of paddy soil 总被引:2,自引:0,他引:2
To understand better the chemical characteristics and source of dissolved organic matter (DOM) leached from the plow layer of rice paddies, a lysimeter study was conducted, which simulated submerged paddy topsoil during rice growth. The fulvic acid (FA) fraction in the percolation water from the lysimeter was collected by adsorption onto insoluble polyvinylpyrrolidone (PVP), and the temporal variations in its elemental composition, molecular size distribution, IR spectra, 13C CPMAS NMR spectra, and δ13C values were investigated. The proportion of the FA fraction to bulk DOM varied greatly, but the chemical characteristics of the FA fraction did not change appreciably during the experimental period. Thus, it is considered that the changes in the DOM composition in percolation water were mainly due to the differing contributions of the FA fraction. Further, to investigate the source of the FA fraction in the leachate, the chemical characteristics of the FA fraction in the leachate were compared with those extracted from the plow layer soil. A sequential extraction of the FA fraction was conducted using a sequence of water, 0.25 M Na2SO4, 0.1 M Na4P2O7 (pH 7.0), 0.1 M Na4P2O7 (pH 10.5), and NaBH4+0.1 M Na4P2O7 (pH 10.5). It was found that the water- and 0.25 M Na2SO4-extractable fractions, which were most mobile, were not the only source of the FA fraction in the leachate. The small molecular size sub-fraction of the NaBH4+0.1 M Na4P2O7 (pH 10.5)-extractable FAs, most of which are probably bound mainly to iron oxides, are considered to be another source of the FA fraction leached from the plow layer of paddy fields. 相似文献
78.
Takeru Kiuchi Kenichi Watanabe Shotaro Nakagun Kazurou Miyahara Noriyuki Horiuchi Yoshiyasu Kobayashi 《Journal of toxicologic pathology》2022,35(1):83
A Chihuahua dog showed persistent itching in the right ear canal. Anti-inflammatory medicines and prednisolone were ineffective and total ear canal ablation was performed. Histological diagnosis was chronic otitis externa. Eosinophilic intranuclear inclusion bodies (Cowdry type A and full-type) were occasionally observed in the ceruminous gland epithelium. The inclusion bodies were negative for nucleic acid and ultrastructurally composed of fibrous structures (approximately 10 nm in width). Viral infection was initially suspected, but polymelase chain reaction tests did not detect the expected viral genes. Immunohistochemistry revealed that the inclusion bodies were positive for heat shock protein 70 (HSP70), suggesting that these bodies could be protein aggregates including HSP70. The etiology of this lesion has not been elucidated, but chronic inflammation may influence the cytoplasm-to-nuclear transportation of HSP70. To the best of our knowledge, this is the first report of canine chronic otitis externa with HSP70-positive intranuclear inclusion bodies. 相似文献
79.
为深入了解海南岛热带野生植物的保健功能及其活性成分,用CCK-8法检测山地五月茶(Antidesma montanum)果和叶的乙醇提取物对MDA-MB-231乳腺癌细胞增殖的抑制活性。结果表明,山地五月茶果和叶的乙醇提取物作用72 h对细胞的半数抑制浓度(IC50)分别为483 μg/mL和306 μg/mL。叶的乙醇提取物分别经石油醚、乙酸乙酯、正丁醇萃取,比较各有机溶剂萃取相及剩余水相对乳腺癌细胞抑制增殖活性,结果显示乙酸乙酯相表现出较高的活性,其处理细胞72 h的IC50为150.5 μg/mL。划痕实验和Transwell检测结果表明,乙酸乙酯相提取物具有抑制MDA-MB-231细胞迁移和侵袭的能力。流式细胞仪检测结果表明,乙酸乙酯相提取物能够使MDA-MB-231细胞周期S期显著延长。UPLC-MS/MS分析结果显示,乙酸乙酯相含有穗花杉双黄酮活性成分。穗花杉双黄酮处理MDA-MB-231细胞72 h的抑制增殖IC50为192.6 μg/mL,表明其是山地五月茶抑癌活性成分之一。 相似文献
80.