烤烟托盘直播育苗基质替代研究

为降低育苗成本,实现烟草托盘直播育苗基质可持续化,采用苗床对比试验方法,开展了腐熟棉籽壳和小麦秸秆完全替代草炭作托盘直播育苗基质的可行性研究。结果表明,60%腐熟棉籽壳+30%耕层土壤+10%细砂配方培育的烟苗主要生物学和生理指标优于或接近添加草炭土的传统直播育苗基质,农艺性状与生理指标协调,均能达到壮苗标准要求,基本具备了作为托盘直播育苗基质的条件,可作为替代草炭土的托盘直播育苗基质配方进行适当示范推广。     

烟草砂培漂浮育苗技术的研发与规程

2005-2006年对砂培替代基质的漂浮育苗技术进行系统研究,开发出砂体作为介质的烟草砂培漂浮育苗操作技术,培育出优于现行漂浮育苗的砂培烟苗。经过生产验证,形成成熟、实用的烟草砂培漂浮育苗技术规程。     

溴甲烷熏蒸烟草苗床(或土壤)灭虫、防病、除草使用说明

用溴甲烷熏蒸烟草苗床或育苗土壤,防治烟草苗期的病、虫、草害,作为烟草生产上培育无病壮苗的一项技术措施,这在世界主要的产烟国家已广泛应用。一、溴甲烷熏蒸烟草苗床(或土壤)的方法溴甲烷是一种有毒的液化气体,由于气体有强大的扩散力,它可以在薄膜覆盖的苗床(或土堆)里向各方位无孔不入地扩散渗透,从而达到灭虫、灭菌防病、除草的目的。     

我国烟草育苗技术现状分析

概要介绍了我国烟草集约化育苗的发展。分析了当前我国烟草漂浮育苗、托盘育苗、湿润育苗和砂培育苗四种主要集约化育苗技术的现状和技术优势,剖析了四种育苗方式存在的主要问题及解决途径。对当前育苗存在的其他问题进行分析并提出建议。     

烟草砂培漂浮育苗技术的研发与规程

2005-2006年对砂培替代基质的漂浮育苗技术进行系统研究,开发出砂体作为介质的烟草砂培漂浮育苗操作技术,培育出优于现行漂浮育苗的砂培烟苗.经过生产验证,形成成熟、实用的烟草砂培漂浮育苗技术规程.     

黄砂、石粉替代漂浮育苗基质对烟苗生长发育的影响

为减少草炭资源的消耗,筛选出适合在四川省各主产烟区推广的烟草育苗替代基质,采用凉山黄砂、攀枝花黄砂、泸州黄砂、宜宾石粉分别配制75%、50%和25%的商品基质进行漂浮育苗试验,研究烟草漂浮育苗基质替代材料与替代比例对烟苗生长发育、生理生化指标、成苗期及成苗率的影响。结果表明,4个地区的黄砂、石粉混配育苗基质可满足烟苗出苗和生长发育的需求。50%黄砂或石粉+50%商品基质为最优配比,其理化性质符合烟草漂浮育苗基质的要求。培育的烟苗出苗率在90%以上,成苗率在82%~84%之间,苗床期为62~64 d,成苗时烟苗茎高、茎围、叶片数、一级侧根数、根系活力、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性以及叶绿素含量(质量分数)均明显优于对照或与对照差异不明显,基质成本比对照降低46.70%。50%黄砂或石粉+50%商品基质的替代比例适合四川省烟区应用。     

喷施微量元素对烟草幼苗生长发育的影响

通过本试验表明,在河南襄城县烟草苗床喷施微量元素铜、锌、溴,可以提高烟草的单株叶面积、叶片内叶绿素含量、地上部和地下部的干重,单位叶面积干重、移栽后返苗速度,以致最终提高烟草产量和产值。烟草苗床喷施硫酸铜、硫酸锌、溴化钾的浓度分别以0.05%、0.10%和0.01%较为合适,效果明显。     

格子盘育苗技术在烟草育种中的应用

格子盘育苗技术在烟草育种中的应用张宪银烟草育种或品种资源研究工作中，涉及到的品种（品系）的个数很多，而每个品种（系）要求的株数较少，有的育种单位每年要对几百甚至上千个株系育苗，给田间播种育苗带来很大困难。一是播种量不易掌握，苗床很难整得细致，增大播种...     

烟草苗期病虫害的综合防治

介绍了烟草苗期主要病害的种类、症状、发病条件及分布 ,如烟草炭疽病、烟草猝倒病、烟草立枯病和主要虫害的种类与分布 ,如地下害虫 (蝼蛄、地老虎、金针虫、蛴螬等 )和蚜虫等。详细介绍了苗期病虫害的综防措施 :①做好苗床地的选择 ;②苗床土、肥的选用与育苗设施的消毒方法 ;③选用无病种子 ;④确保苗期卫生 ;⑤主要病虫害的药剂防治 ;⑥加强苗期管理     

我国烟草漂浮育苗技术应用现状、研究进展及发展方向

通过介绍我国烟草漂浮育苗技术应用现状和研究进展,指出了漂浮育苗技术的使用优势,探讨了目前我国漂浮育苗技术应用存在的问题及解决对策,提出了漂浮育苗发展新方向,为烟草漂浮育苗技术研究及大田生产提供参考.     

几种土壤熏蒸剂防除烟草苗床杂草的药效试验

对35%"线克"水剂、98%"必速灭"微粒剂、32 7%"维博亩"水剂、32 7%"斯美地"水剂、33 6%"适每地"水剂、98%"棉隆"微粒剂和98%溴甲烷压缩气体等7种不同土壤熏蒸剂防除烟草苗床杂草效果进行了试验。结果表明,7种土壤熏蒸剂对苗床杂草均有较好的防除效果。播种后20d、40d时各处理对杂草数量的平均防效均分别达到95%和90%以上,几种试验药剂与对照药剂溴甲烷相当,可替代溴甲烷在烟草苗床除草中应用。     

SELECTED ALTERNATIVES TO METHYL BROMIDE IN THE POSTHARVEST AND QUARANTINE TREATMENT OF ALMONDS AND WALNUTS: AN ECONOMIC PERSPECTIVE

Methyl bromide is a highly effective fumigant used in the postharvest and quarantine treatment of tree nuts. There will be a complete phase out in the United States of America (U.S.) of methyl bromide by 2005 according to The Montreal Protocol of 1991 with the exception of preshipment and quarantine uses as stated in the 1998 Clean Air Act. This study analyzed alternative treatment scenarios. The alternatives considered were phosphine, irradiation, and controlled atmosphere storage. Costs for each scenario were developed. Cost increases with irradiation ranged from two to fourteen times the benchmark costs for methyl bromide. Controlled atmosphere storage for both commodities had cost increases ranging from 174% to 256% over methyl bromide costs. Phosphine was used only to treat almonds. Phosphine application costs were 108% and 117% above the benchmark costs for methyl bromide.     

烟草漂浮育苗系统中培养基质对烟苗生长发育影响的研究

本文研究了烤烟漂浮育苗系统中培养基质对烟苗生长发育的影响。结果表明,1.漂浮育苗基质中有机质材料的比例对烟苗生长发育具有重要作用。在以草炭、蛭石、膨化珍珠岩为原料的培养基中草炭比例以5 0%~70%较为适宜,低于40%或高于80%均影响烟苗根系的发育。2.有机质材料的选择应充分利用当地自然资源条件,因地制宜开发利用。以一定比例的腐熟作物残体代替草炭亦是完全可行的,同样能够培育出根系发达,均匀一致的壮苗。3.基质配比确定后,苗盘中基质容重对烟苗影响较大。试验以美国漂浮育苗商品基质Sunshine Tobacco Mix L 5为材料,证明苗盘装填容重在0.15~0.2 5 g/m L适宜于烟苗的生长发育。4.基质中加入少量的肥料,有利于烟苗前期的发育,肥料浓度超过5 0 mg/L即影响烟苗生长。试验显示营养液中的氮和钙、镁、铜、铁、锰等元素在基质上部富集,可产生肥料盐害。5.漂浮育苗与传统育苗方式相比,烟苗移栽大田后还苗快,生长迅速,增加收获叶片数,促进烟株开片开秸,为烟叶的优质丰产奠定了良好的基础。      

Predictors of crop diversification: a survey of tobacco farmers in North Carolina (USA)

OBJECTIVE: To assess the attitudes and behaviours of North Carolina tobacco farmers around crop diversification. DESIGN: Cross-sectional telephone survey. PARTICIPANTS: Active tobacco farmers in 14 North Carolina counties (n = 1236), interviewed between January and April 1997 (91% response rate). OUTCOME MEASURES: Interest in, experience with, and perceived barriers to diversification. RESULTS: Most farmers (95%) grew/raised a commodity other than tobacco (mean = 2.8). A total of 60% of farmers expressed interest in trying other on-farm activities to supplement their tobacco and 60% reported taking action in the past year around supplementation. Younger age and college education were positively associated with interest. College education, off-farm income, and larger farm size were associated with the number of actions taken. For perceived external barriers to diversification, use of tobacco, percent income from tobacco, lack of college education, and younger age were most strongly associated with the number of barriers. For internal barriers (personal factors), percent income from tobacco, use of tobacco, and lack of college education were most strongly associated with the number of barriers. CONCLUSIONS: Most farmers were involved in diverse operations and expressed interest in continuing to diversify, although the breadth of diversification was narrow. Farmers noted many barriers to diversifying. If conventional production and marketing techniques are employed for non-tobacco alternatives, these alternatives may not provide the sustainable profitability that tobacco has afforded. Competition from foreign tobacco growers is the primary threat to the future of American growers and tobacco dependent communities.     

烟草包衣种子辅料筛选及配比试验

针对目前烤烟常规包衣种子存在的问题和漂浮育苗技术广泛应用的现状,结合我国的烤烟生产实际,研制开发了烤烟漂浮育苗专用包衣种子并应用于烟叶生产中。对种子包衣辅料进行筛选,初步选定了4种主要的包衣辅料并进行了10种不同配比的包衣加工试验,对不同配比加工的种子进行外观物理性状测定。结果表明,处理6和处理2的种子在均匀度、裂解度、光泽度等方面均优于其它处理。     

樱桃中溴形态分析方法及其在熏蒸过程追溯中的应用

建立樱桃中溴形态的分析方法,对比未熏蒸与熏蒸后樱桃中溴甲烷残留量和无机溴含量,研究溴甲烷熏蒸与溴残留的关系。采用水超声提取,以36 mmol/L硝酸＋67 mmol/L氨水作为流动相,经阴离子色谱柱分离,高效液相色谱-电感耦合等离子体质谱法分析樱桃中的溴形态,并使用电感耦合等离子体质谱法确证樱桃中总溴含量,顶空进样-气相色谱法检测樱桃中溴甲烷残留量。研究表明,溴形态分析方法中溴酸根的回收率在89.7%～101.4%之间,相对标准偏差为2.1%～3.5%,溴离子回收率为85.5%～107.3%,相对标准偏差为4.4%～7.0%,定量限为0.10 mg/kg。溴甲烷熏蒸后樱桃中只含有溴离子,其含量与总溴含量相符。熏蒸后樱桃中的溴甲烷残留量随时间递减,溴离子含量明显高于未熏蒸,且不受时间与保存条件的影响产生显著变化。本方法可对樱桃的溴甲烷熏蒸过程进行追溯,为水果的进出口风险监控和质量控制提供依据。     

Methyl bromide—Is there any future for this noteworthy fumigant?

For many years methyl bromide has played a significant role in controlling insect pests in durable and perishable agricultural commodities, pests in the soil and in structures. Although about 10% of the chemical produced is used globally for disinfesting stored products its importance for that purpose cannot be understressed, since it is the only remaining fumigant in worldwide use other than phosphine. Methyl bromide is the only fumigant available for quarantine treatment of commodities where rapid disinfestation techniques are essential. Although methyl bromide arises from natural sources, principally the oceans, most of the chemical found in the stratosphere is now thought to originate from man-made sources. Methyl bromide has been formally listed as an ozone-depleting substance by the Parties to the Montreal Protocol, with agreement from 1995 to limit future production. Reviews of both the current uses of methyl bromide, and of potential substitutes should permit a decision on a general control scheme for the chemical by 1995. Separately, in the U.S.A., under the Clean Air Act, methyl bromide will be phased out by the year 2001. Other countries or political unions are also currently examining the feasibility of reducing the quantities of methyl bromide used. Future restrictions on methyl bromide are expected to have a particular impact on developing countries, particularly those exporting agricultural products. This has been recognized in exempting these countries from the controls to be introduced in 1995. Despite many uncertainties regarding its role in ozone depletion it seems certain that methyl bromide will, eventually, be removed from the list of the few remaining products capable of preventing pest damage to food and other valuable commodities.     

Residues after fumigation with methyl bromide: bromide ion and methyl bromide in middlings and final cereal foodstuffs

Methyl bromide and bromide ion concentrations were estimated in pasta manufactured before and after fumigation with methyl bromide. The first trial estimated the bromide ion concentrations in fumigated and unfumigated flours and in pastas obtained from these. The concentration of bromide ions in fumigated flours was not significantly different from unfumigated flours. Only some pastas, manufactured from fumigated flours, showed a higher bromide ion concentration than those manufactured from unfumigated flours. The second trial evaluated the bromide ion concentrations of rices, white flours, flours, pastas made only from flours, pastas with eggs and pastas with eggs and spinach, before and after exposure to methyl bromide in their retail packagings. The bromide ion concentrations in fumigated pastas with eggs, pastas with eggs and spinach and rice were higher than in those unfumigated. In the pastas with eggs the bromide ion concentration after fumigation increased ten times (from about 4 to 40 mg/kg). Results showed that the bromide ion and methyl bromide levels estimated in all the foodstuffs examined were lower than the maximum limits fixed by several different national regulations.     

硫酸-甲醇衍生化对烟草中乙酰丙酸质量分数测定的影响

为考察采用硫酸-甲醇衍生化方法测定烟草中乙酰丙酸质量分数的可靠性,分析了硫酸-甲醇衍生化时间和温度对烟草中乙酰丙酸质量分数测定的影响,探索了5种糖类成分在硫酸-甲醇衍生化条件下是否产生乙酰丙酸甲酯,比较了263个烟草实际样品中果糖和蔗糖质量分数与乙酰丙酸质量分数的关系。结果表明：(1)硫酸-甲醇衍生化时间和温度对烟草样品甲酯化产物中乙酰丙酸甲酯响应的影响不同于其他有机酸甲酯,且这种不同与烟草基质有关;(2)果糖和蔗糖在硫酸-甲醇衍生化条件下能产生乙酰丙酸甲酯,而葡萄糖、麦芽糖和肌醇在衍生化过程中不产生乙酰丙酸甲酯;(3)蔗糖在硫酸-甲醇衍生化条件下产生的乙酰丙酸甲酯的质量仅为相同质量果糖产生的1/2;(4)利用硫酸-甲醇衍生化法测定得到的烟草中乙酰丙酸的质量分数受烟草中果糖和蔗糖的影响。     

防御低温育苗技术对烤烟一些酶活性及烟叶经济性状的影响

针对粤北及粤东烟区普遍存在的早春低温影响烤烟育苗的问题,以烤烟新品系华烟06为材料,采用在苗床下铺设酿热物进行有氧发酵,并改良营养液配方的防御低温育苗技术,研究其对烤烟大田生长期生理特性及产质量的影响.试验表明:与常规漂浮育苗相比,采用防御低温育苗技术培育的烟苗移栽大田后烟叶中淀粉酶、酸性蔗糖转化酶、硝酸还原酶的活性明显提高.烤后烟叶中水溶性总糖、还原糖、钾、总氮、烟碱、蛋白质含量增加,淀粉含量降低,产量、产值、上等烟比例和均价均优于常规漂浮育苗.同时,在底物中添加发酵剂有明显促进发酵增温的作用.综合分析表明,苗床下铺设2kg稻草秸秆和24kg花生麸并添加发酵剂的防御低温育苗技术的效果最好,适合在产区推广应用.