SO2对葡萄采后呼吸强度及内源激素的影响

采用气相色谱法和改进的高效液相色谱法研究发现：‘无核白’葡萄果粒为非跃变型呼吸类型，其乙烯释放量很低，但释放潜力很高，切伤后乙烯释放速率迅速增高；果梗和穗梗为跃变型呼吸类型，有很高的呼吸高峰和乙烯释放高峰。适量的ＳＯ２保鲜处理对葡萄的呼吸强度、脱落酸（ＡＢＡ）含量及乙烯释放具有明显抑制作用，对生长素（ＩＡＡ）、赤霉素（ＧＡ）有促进作用，既可抑制葡萄生理衰老，又可减轻葡萄的落粒，延长葡萄采后贮藏寿命     

熏蒸直接提取法测定土壤MB－S中几个因素的研究

就影响薰蒸直接提取法测定土壤ＭＢ－Ｓ的一些因素（预培养时间和土壤湿度，氯仿消杀时间，浸提剂与土壤比例和振荡时间）进行了研究，提出了适用于一般实验室测定土壤ＭＢ－Ｓ的较好程序。     

土壤硫素形态及其转化研究进展

本文综合国内外有关资料 ,阐述了土壤有机硫和无机硫在土壤中的形态、转化及其有效性 .明确了土壤有机硫形态的分级方法、有机硫的矿化及其影响因素以及外源无机硫和有机硫在土壤中的转化及生物有效性 .     

四川省土壤有效硫状况及硫肥效应研究

通过对四川省 6类 32 9个土壤样品的有效硫的分析 ,结果表明缺硫及潜在性缺硫土样占总样本的 2 3 1 % .但结合田间试验 ,在四川盆地特定环境条件下 ,即使土壤耕层有效硫处于缺乏范围 ,增施硫肥对玉米、小麦、油菜产量无明显增加 ,并就产生的原因作了初步分析 .通过对土壤硫素平衡的测算 ,预测在近期内 ,四川盆地主要农耕地不会发生大面积缺硫问题     

福建耕地土壤硫肥效应及其临界指标研究

硫是作物生长发育所需的营养元素。根据多年多点田间试验和土壤有效硫测定,研究福建主要粮经作物的硫肥效应、土壤有效硫临界指标和耕地土壤硫肥力状况。64个田间试验表明,福建主要农作物施用硫肥平均增产10.5%,增产幅度是旱作物>水稻>香蕉;水田土壤和旱地土壤有效硫临界指标分别为23mgkg-1和25mgkg-1。根据全省372个耕层土样有效硫测定结果,土壤有效硫含量平均为27.6mgkg-1,低于土壤有效硫临界值的样品数占57.0%,其中,闽东南地区耕地土壤有效硫缺乏程度比闽西北地区高;在土地不同利用类型中,旱地土壤有效硫总体比水田匮乏,旱地土壤有效硫平均含量是茶果园>菜园>农地,其中,农地土壤有效硫低于临界指标的样品占75.3%;水田中不同土种的土壤有效硫含量以埭田最高,灰沙泥田为最低,旱地则以灰赤土最高而风沙土最低。     

A risk assessment of sulphur deficiency in cereals using soil and atmospheric deposition data

Abstract. A qualitative model was used to assess the risk of S deficiency in cereals in Britain. A risk index was generated for each of 6301 soil data points by considering the inputs of S from atmospheric deposition, the content of soil organic matter, and factors influencing the potential leaching of sulphate, i.e. soil type, texture, pH and annual rainfall. The results show that currently 11% of the British land area is at high risk of S deficiency, and a further 22% at medium risk. The high risk areas are in south-east Scotland, the Scottish Borders, East Anglia, the Welsh Borders and south-west England. These agree well with the distribution of reported incidences of S deficiency in cereals. If the UK target for reduction in SO₂ emissions by the year 2003 is met, the model predicts that the high and medium risk areas will increase to 23 and 27%, respectively. Thus, agricultural use of S-containing fertilizers is likely to increase in importance in the near future.     

Field Evaluation of Ammonium Sulfate versus Two Fertilizer Products Containing Ammonium Sulfate and Elemental Sulfur on Soybeans

ABSTRACT

Two separate field trials comparing three different commercial sulfur (S) fertilizers were conducted in 2016 and 2017, respectively, to evaluate their initial agronomic effectiveness in increasing soybean grain yield. The S compounds of these products were elemental S (ES) and ammonium sulfate (AS). The fertilizer sources were (1) AS, (2) granular MAP-10 S (5% ES + 5% AS-S) and (3) bulk-blend (bentonite-ES) + (AS) containing 25% ES + 25% AS-S. Rates of total S applied were 0, 5.6, 11.2, 22.4 and 33.6 kg S ha^?1. A significant S response in grain yield was observed with all S sources. The grain yield was significantly higher with AS than with the other two S sources at S rates ≤22.4 kg S ha^?1 of total S applied but equal for all sources above this rate. All data points for the three S sources followed the same S response function based on a quadratic plateau model when the grain yield was plotted versus AS-S rate applied. This suggests that there was no significant ES oxidation from MAP-10S and (ES) + (AS) products to provide soybean crop growth to maturity. The experimentally observed AS-S rate at which the maximum grain yield was attained in the 2 years of fieldwork was 11.2 kg S ha^?1 while the calculated average AS-S rate based on a quadratic plateau model was 13.4 kg S ha^?1.

Abbreviations: AS: ammonium sulfate; ES: elemental S; MAP: monoammonium phosphate; DAP: diammonium phosphate; TSP: triple superphosphate.     

硅钙肥、生石灰、硫肥三因素二次多项式回归大豆产量效应分析

对硅钙肥、生石灰、硫磺粉三种肥料因素进行了二次多项式大豆产量回归分析.结果表明,硫磺粉的产量灵敏度峰值和单因素产量峰值最高,硅钙肥居中,生石灰最低;互作效应对产量的作用表现为硅钙肥与硫磺粉的互作对产量作用极显著.硫磺粉对产量作用相对较大.在本试验条件下,大豆单产水平≥3 000 kg/hm^2的施肥方案为,硫磺粉14.0 kg/hm^2,硅钙肥和生石灰免施;大豆单产水平≥3 200 kg/hm^2,硫磺粉43.0 kg/hm^2,硅钙肥和生石灰免施.     

南京气象学院简单空气质量数值预报模式系统研究

建立了一个简单空气质量数值预报模式系统,该系统由中尺度数值预报模式（MM5）、Pielke中-β尺度气象模式和Euler大气平流—扩散模式以及Erisman干沉降模式组成。该模式系统具有资料获取容易、结构简单、使用方便、运行稳定等特点。应用该模式系统对南京、沈阳等城市的SO2浓度值进行了预报试验,结果表明,该模式系统能够较为准确地模拟城市范围内污染物的时空分布,可用于城市空气质量预报业务,现已在上海和南京的空气质量预报业务中得到应用。     

Effect of nitrogen and sulfur interaction on growth and pungency of different pseudostem types of Chinese spring onion (Allium fistulosum L.)

Effects of N and S supply on the growth and pungency (estimated as pyruvic acid levels) of Chinese spring onion (Allium fistulosum L. var. giganteum Makino) were investigated in two pot experiments using soilless growing media. In the first experiment the effects of S supply (0.01 and 4.00 mmol L⁻¹ SO₄²⁻) on the growth and pungency of Chinese spring onion were investigated among four cultivars with fleshy root type or long pseudostem type. In the second experiment the effects of different S (0.01 and 4.00 mmol L⁻¹ SO₄²⁻) and N (1.5, 3.0, 6.0, 12.0 and 24.0 mmol L⁻¹ N) supply levels on the growth and pungency of Chinese spring onion were studied. Fleshy root spring onion had stronger pungency and larger pseudostem diameter than long pseudostem spring onion, and the pungency of fleshy root spring onion was regulated to a greater extent by N and S supply compared with long pseudostem spring onion. Increasing S supply level significantly increased the biomass, N and S uptake and pungency of all cultivars tested. The biomass of Chinese spring onion of fleshy root type (cv Longyao) and long root type (cv Zhangqiu) was more influenced by N supply than it was by cultivar or S supply. Low S supply decreased the pungency of the two cultivars with increasing N supply. No significant differences in N or S uptake or pungency were observed in the two cultivars with different S supply at the N supply level of 1.5 mmol L⁻¹ N, however, cultivar differences in N and S uptake and pungency were investigated at high N supply (12.0 mmol L⁻¹ N) and S supply (4.0 mmol L⁻¹ SO₄²⁻). Excessive N supply (24.0 mmol L⁻¹) significantly inhibited plant growth, retarded S assimilation, and decreased pungency. It is therefore essential to apply the optimum recommended rate of N fertilizer in Chinese spring onion production.