MnSO_4浸种对马铃薯幼苗质量及产量形成的影响

以"克新13"马铃薯为材料,通过盆栽试验,利用不同浓度的硫酸锰浸种处理,通过测定马铃薯幼苗的地上部干重、地下部干重、壮苗指数、叶片叶绿素含量、根系活力及产量等指标的变化,研究硫酸锰对马铃薯幼苗质量及产量的作用效应。结果表明:适宜浓度硫酸锰(0.06%~0.09%)浸种处理能有效地提高叶绿素含量和根系活力,促进幼苗地上部和地下部干物质积累,提高壮苗指数,从而提高幼苗质量和产量;硫酸锰过量,则抑制了马铃薯幼苗的正常生长,从而影响了产量的形成。     

不同浓度硫酸盐对水稻土中异化铁还原过程的影响

研究不同电子受体之间的竞争关系对揭示厌氧水稻土中微生物作用导致的氧化还原过程变化机理具有重要的理论意义。本研究采用土壤泥浆厌氧培养、人工合成氧化铁体系接种土壤浸提液厌氧培养及接种铁还原菌纯培养等试验方法,通过向培养体系中添加SO24-,探讨了硫酸盐作为竞争电子受体对不同铁还原体系中Fe（Ⅲ）还原的影响。结果表明,在2种水稻土的泥浆培养过程中,Fe（Ⅲ）还原速率均随着SO24-浓度增加而降低,但Fe（Ⅱ）的最终累积量却较对照处理有明显的增加。添加硫酸盐对Fe（Ⅲ）还原速率（k）的影响表现为：石灰性水稻土〉酸性水稻土;而最终Fe（Ⅱ）累积增加率则为：酸性水稻土〉石灰性水稻土。由接种不同水稻土浸提液的培养试验看出,添加SO24-后Fe（Ⅲ）还原受到显著的抑制,但随着培养时间延长Fe（Ⅲ）还原反应依然可以进行,并且Fe（Ⅱ）累积量最终达到与CK相同的水平。在接种铁还原菌的纯培养试验中,添加SO24-对供试的4株铁还原菌的Fe（Ⅲ）还原过程并未产生抑制效应,表明铁还原菌本身并不受硫酸盐的影响。     

Effect of Conditioning Zinc Sulfate Heptahydrate (ZnSHH) with Zinc Oxide (ZnO) and Neem Oil on Growth,Productivity, Zinc Biofortification of Grain and Zinc Uptake by Basmati Rice

Commercial grade zinc (Zn) sulfate hepta hydrate (ZnSHH) is the most widely used source of Zn in India and several other countries for amelioration of Zn deficiency in crops. However, it releases water of hydration at temperature above 30°C and forms lumps on storage, which make it difficult to handle it and apply in fields. Therefore, conditioning of ZnSHH with ZnO and neem oil reduces the release of water of hydration and prevents lumps formation and can be well stored. Field experiments were conducted at the research farm of the Indian Agricultural Research Institute, New Delhi, India during rice growing seasons (July-November) of 2009 and 2010 to study the effect of conditioning ZnSHH with ZnO and neem oil on growth, productivity and Zn fortification of rice (Oryza sativa) grain and uptake by Basmati rice ‘Pusa 1121’. The experiment was conducted in a randomized block design with 3 replications comprised of 9 treatments of Zn fertilization. The present study shows that when conditioned with 2% ZnO and 4% neem oil ZnSHH improved yield attributes, grain and straw yields, Zn uptake and partial factor productivity (PFP), agronomic efficiency (AE), recovery efficiency (RE), and physiological efficiency (PE) of Zn in Basmati rice ‘Pusa 1121’. In general, ZnO was inferior to ZnSHH. Application of ZnSHH conditioned with 2% ZnO and 4% neem oil can be a better source of Zn for transplanted puddled Basmati rice on Zn deficient soils.     

Inhibitors of methane production in paddy soils

Global warming is now attracting the world attention. Methane is an important greenhouse gas next to CO₂. Prather et al. (1995) estimated that rice paddy fields account for 14% of all biogenic atmospheric methane. It is considered that methane production from rice paddy fields is increasing along with the increase of the population. Therefore, the development of rice cultivation techniques for reducing methane production is essential, in order to preserve the global environment.     

物化法去除糖蜜酒精废水硫酸盐效果及其产气性能的比较

糖蜜酒精废水中高浓度的硫酸盐会抑制生化处理产甲烷性能。该文采用活性炭、Ba Cl2·2H2O、Ca(OH)2及铁碳微电池法对糖蜜酒精废水中的硫酸盐进行预处理,并分析了预处理前后硫酸根及化学需氧量COD的变化,同时,也分析评价了几种方法对产气性能的影响。结果表明:在500.0 g糖蜜酒精废水中加入8.0 g活性炭,硫酸根去除率达80.0%以上,且产气性能相对最好,累计产气率可达437.3 m L/g。在500.0 g糖蜜酒精废水中,根据S元素含量和Ba SO4的分子组成比例,添加70%的化学试剂Ba Cl2·2H2O,能全部去除硫酸根,累计产气率可达483.2 m L/g,产气效果相对最好,同等条件下,添加70%的Ca(OH)2,硫酸根也能全部去除,累计产气率可达436.6 m L/g。铁碳微电池处理的糖蜜酒精废水,能有效抑制硫酸根的影响,并且可以提高废水的可生化性,累计产气率为451.0 m L/g,是对照处理293.1 m L/g的1.5倍。各处理效果的产气性能排序为70%Ba Cl2·2H2O铁碳微电池8.0 g活性炭吸附70%Ca(OH)2对照组。     

氮肥形态对香蕉种植土壤中氨氧化细菌与古菌的影响

氨氧化微生物通过影响氮素在土壤中的转化而间接影响作物对不同氮素形态的吸收。因此,本实验采集了海南省种植香蕉的滨海土壤,通过施用硫酸铵和硝酸钙,研究了氨氧化细菌(AOB)和氨氧化古菌(AOA)的数量与群落的变化,并测定了香蕉的生长与氮营养状况。通过构建氨氧化细菌和古菌的功能基因amo A文库后发现:施用硫酸铵的土壤中AOB的amo A基因拷贝数显著高于施用硝酸钙的土壤和不施肥的土壤,而AOA的拷贝数低于硝酸钙与不施肥处理。但是氨氧化古菌AOA的绝对数量都高于AOB。施用硫酸铵的土壤中AOB的群落多样性和丰富度明显增加,而施用硝酸钙的土壤却没有发生显著变化。施用硫酸铵和硝酸钙的土壤中AOA群落结构相似,但丰富度和多样性均高于不施肥处理。从施肥效果看,相比硫酸铵,硝酸钙显著提高了香蕉植株的生物量和全氮含量。上述结果表明,在南方酸性土壤中AOA占优势,虽然施用铵态氮肥可以促进AOB的丰度与多样性,但是很可能会抑制AOA的数量。因此,在海南滨海土中施用铵态氮肥后,通过硝化作用以满足香蕉吸收硝态氮的需求达不到理想的效果,应直接补充硝态氮肥来促进香蕉生长。     

不同含水量天然硫酸盐盐渍土中二氧化碳和氧化亚氮的排放

Soil salinization may negatively affect microbial processes related to carbon dioxide(CO_2) and nitrous oxide(N_2O) emissions. A short-term laboratory incubation experiment was conducted to investigate the effects of soil electrical conductivity(EC) and moisture content on CO_2 and N_2O emissions from sulfate-based natural saline soils. Three separate 100-m long transects were established along the salinity gradient on a salt-affected agricultural field at Mooreton, North Dakota, USA. Surface soils were collected from four equally spaced sampling positions within each transect, at the depths of 0–15 and 15–30 cm. In the laboratory, artificial soil cores were formed combining soils from both the depths in each transect, and incubated at 60% and 90% water-filled pore space(WFPS) at 25?C. The measured depth-weighted EC of the saturated paste extract(EC_e) across the sampling positions ranged from 0.43 to 4.65 dS m~(-1). Potential nitrogen(N) mineralization rate and CO_2 emissions decreased with increasing soil EC_e, but the relative decline in soil CO_2 emissions with increasing ECe was smaller at 60% WFPS than at 90% WFPS. At 60% WFPS, soil N_2O emissions decreased from 133 μg N_2O-N kg~(-1) soil at EC_e 0.50 dS m~(-1) to 72 μg N_2O-N kg~(-1) soil at EC_e = 4.65 dS m~(-1). In contrast, at 90% WFPS,soil N_2O emissions increased from 262 μg N_2O-N kg~(-1) soil at EC_e = 0.81 dS m~(-1) to 849 μg N_2O-N kg~(-1) soil at EC_e = 4.65 dS m~(-1), suggesting that N_2O emissions were linked to both soil ECe and moisture content. Therefore, spatial variability in soil EC_e and pattern of rainfall over the season need to be considered when up-scaling N_2O and CO_2 emissions from field to landscape scales.     

生物柴油Fe_2(SO_4)_3—Al_2O_3固体酸催化剂的制备

为了解决硫酸铁催化制备生物柴油过程中存在的回收难和部分溶于水等问题,制备了Fe2(SO4)3—Al2O3负载型固体酸催化剂。考察了负载量、焙烤温度、焙烤时间对催化剂活性的影响。结果表明,负载量20%的催化剂在300℃下,焙烤超过4h,活性最高,延长焙烤时间对催化剂活性没有显著影响。对不同焙烤温度下的催化剂进行了扫描电镜、能谱和X射线衍射分析,结果显示300℃下,焙烤的催化剂具有最小的晶粒;超过300℃,催化剂上的Fe2(SO4)3组分开始分解。     

Effect of ABA,arginine and sucrose on protein content of date palm somatic embryos

Abscisic acid (ABA), arginine and sucrose were evaluated for their effects on the morphology, germination rates and protein content of date palm somatic embryos (SE). Different concentrations of these supplements in the culture medium were used. The comparative study of SE length and thickness between treated and untreated SE revealed no differences, except for ABA (20 μM), which increased thickness. A decrease of water content (WC) in favor of an increase in dry weight (DW) was observed in all treated SE, especially with sucrose (90 g l⁻¹) and ABA (20 μM). Only ABA (20 and 4 μM) caused a proliferation rate of the cultures higher than those in the control. Although all the tested compounds increased protein content, ABA (20 μM) was more effective in protein enrichment than arginine and sucrose treatments. The SDS-PAGE protein profiles showed a significant difference between treated and untreated SE. A protein band of 22 kDa, identified as glutelin in a previous work, was accumulated after treatment with 20 μM ABA or 3 mM arginine. These findings may contribute to further understanding of the mechanisms involved in the accumulation of specific storage proteins in several plants.     

两种不同镁盐在牛粪堆肥高温期的保氮效果研究

利用恒温培养箱模拟堆肥高温期,添加硫酸镁、磷酸二氢钾和含镁废渣,研究磷酸铵镁(MAP)反应中各成分的保氮效果以及含镁废渣作为堆肥过程中氮素固定剂的可行性。结果表明:添加镁盐固定剂显著降低了堆体中的pH值,减少了氮素损失。同时添加硫酸镁和磷酸二氢钾的保氮效果最佳,添加相同比例的含镁废渣和硫酸镁的保氮效果无显著差别。含镁废渣添加量的保氮效果与其添加量成正相关,添加质量比为2%、4%、8%的含镁废渣的保氮率分别为6.15%、10.13%、19.51%。添加镁盐会提高堆体中的EC值,降低GI值,各处理均可达到腐熟。说明可以利用镁盐作为堆肥保氮固定剂,而含镁废渣因其价格低廉,更具应用前景。