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1.
Mayu Onodera Takayuki Nakajima Masami Nanzyo Tadashi Takahashi Donghe Xu Koki Homma 《Plant Production Science》2013,16(2):262-274
ABSTRACT Soil salinity is a major constraint to sustainable crop production. Genetic improvements are needed for growing soybean in salinity-prone environments. Salt-tolerant soybean genotypes alleviate a reduction in photosynthesis and growth under saline conditions; however, the detailed mechanisms involved remain unclear. Here, we aimed to clarify how Na and Cl root-to-leaf transport is quantitatively regulated, and to identify whether photosynthetic tolerance depends on traits associated with either stomata or with mesophyll tissues. Two pairs of pot-grown soybean near-isogenic lines (NILs) consisting of tolerant and susceptible counterparts, derived from a cross between salt-tolerant FT-Abyara and salt-sensitive C01, were subjected to salinity treatment in a rainout greenhouse. Comparison of photosynthetic responses between genotypes indicated that genotypic differences in salinity tolerance depended on the ability for sustained CO2 assimilation in mesophyll tissues, rather than stomatal conductance. The ratio of photosynthetic rate to intercellular CO2 concentration (A/Ci) declined exponentially with increasing Na and Cl concentration regardless of genotype, but tolerant genotypes effectively kept both elements at significantly low levels. Under saline conditions, tolerant genotypes reduced Na and Cl content at the two transport pathways: from root to stem, and from stem to leaf, but the reduction of Cl at each pathway was only minor. These results suggest that integrating genetic capacity for Cl transport regulation and osmotic adjustment should be an important target in salinity-tolerance soybean breeding. 相似文献
2.
《Communications in Soil Science and Plant Analysis》2012,43(1):63-69
Abstract The absorption mechanisms for Na, K, SO4 and Cl were tested in a salt tolerant (PVR 1) and a salt sensitive (GEB 24) rice varieties. The salt tolerant variety accumulated significantly larger amounts of Na than the salt sensitive variety. Further, PVR 1 absorbed SO4 from Na2SO4 in preference to that from K2SO4. The absorption patterns for K and Cl were similar in both the varieties. It is concluded that the capacity of plant species to accumulate greater amounts of Na is a reflection of their halophytic feature. 相似文献
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测定了产气荚膜梭菌B型、D型和腐败梭菌在新研制的厌氧菌基础培养基中的生长曲线和产毒能力等特性。结果表明,这些细菌可以在新培养基中良好生长和产毒。产气荚膜梭菌B 型经2 h 的适应期后,很快进入对数生长期,培养到8 h细菌密度接近最高值,OD630为4.329;经检测,培养4 h~24 h的细菌所产生的毒素(培养物上清)1μL~2μL可致死KM小鼠。产气荚膜梭菌D型的生长速度也较快,无适应期就直接进入对数生长期,培养到12 h 时细菌密度最高, OD630 为1.75;细菌最佳产毒期在6 h~14 h,培养物上清0.5μL~0.65μL可致死KM小鼠。腐败梭菌生长速度较慢,经6 h的适应期后,才进入对数生长期,培养到14 h时细菌密度最高,OD630为1.335;细菌毒力在培养后的6 h~24 h内10μL菌液可达到在24 h内致死KM小鼠的效果。 相似文献
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The extraction of earth alkaline and alkali metals (Ca, Mg, K, Na), heavy metals (Mn, Fe, Cu, Zn, Cd, Pb) and Al by 1 M NH4NO3 and 0.5 M NH4Cl was compared for soil samples (texture: silt loam, clay loam) with a wide range of pH(CaCl2) and organic carbon (OC) from a forest area in W Germany. For each of these elements, close and highly significant correlations could be observed between the results from both methods in organic and mineral soil horizons. The contents of the base cations were almost convertible one‐to‐one. However, for all heavy metals NH4Cl extracted clearly larger amounts, which was mainly due to their tendency to form soluble chloro complexes with chloride ions from the NH4Cl solution. This tendency is very distinct in the case of Cd, Pb, and Fe, but also influences the results of Mn and Zn. In the case of Cd and Mn, and to a lower degree also in the case of Pb, Fe, and Zn, the effect of the chloro complexes shows a significant pH dependency. Especially for Cd, but also for Pb, Fe, Mn, Zn, the agreement between both methods increased, when pH(CaCl2) values and/or contents of OC were taken into account. In comparison to NH4Cl, NH4NO3 proved to be chemically less reactive and, thus, more suitable for the extraction of comparable fractions of mobile heavy metals. Since both methods lead to similar and closely correlated results with regard to base cations and Al, the use of NH4NO3 is also recommended for the extraction of mobile/exchangeable alkali, earth alkaline, and Al ions in soils and for the estimation of their contribution to the effective cation‐exchange capacity (CEC). Consequently, we suggest to determine the mobile/exchangeable fraction of all elements using the NH4NO3 method. However, the applicability of the NH4NO3 method to other soils still needs to be investigated. 相似文献
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含氯离子土壤有机质分析方法的初步研究 总被引:2,自引:0,他引:2
本文探讨了用提前加H2SO4的方法来消除氯离子对测定土壤有机质的干扰。 相似文献
8.
采用恒温搅拌回流的方式制备了[Rh(COD)Cl]_2,并通过正交试验对制备条件进行了优化,得出催化剂适宜制备条件:n(COD)∶n(RhCl_3·3H_2O)为3.5∶1,回流温度80℃,回流时间3 h。将制备的[Rh(COD)Cl]_2作为催化剂用于松节油的氢化反应,通过单因素试验和正交试验考察了反应压力、反应温度、催化剂用量及反应时间对反应的影响,优选出适宜反应条件,即4 g松节油,催化剂用量为松节油质量的2.5%,反应压力2.5 MPa,反应时间4 h,反应温度45℃。在此反应条件下,α-蒎烯转化率为98.21%,产物顺式蒎烷对映选择性为97.46%,收率为95.72%。 相似文献
9.
By using Particle-Induced X-ray Emission (PIXE) technique, the effect of arsenic (As) on the mineral contents and translocation in the xylem of rice (Oryza sativa L. cv. ‘Akihikari’) was studied. The results suggest that exogenous As increased the concentrations of phosphorus (P), calcium (Ca) magnesium (Mg), sulfur (S), and manganese (Mn) in xylem, while the concentrations of potassium (K) remained unchanged. The highest concentration of As to the rice roots did not have any clear effect on the translocation of P, Ca, S, and chlorine (Cl) in the xylem, indicating that the increasing concentrations of the minerals may be due to a condensation effect, resulting from the repression of water movement in xylem by As-toxicity. Among the metal micronutrients, As decreased the concentrations and translocations of iron (Fe), zinc (Zn), and copper (Cu). 相似文献
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