对棉花进行综合化学处理

乌兹别克科学院于1963年对除莠剂(氯苯胺灵、可乐津、茅草枯、草克死、菌达灭、灭草隆、敌草隆和伐草隆等)的不同化学组成及其与有前途的杀虫剂(七氯、八甲磷和灭蚜松)的结合使用进行了研究。业已表明,在棉花出苗前每公顷施用伐草隆3公斤效果最好,被抑制的一年生杂草可达97%。其它除莠剂如敌草隆、可乐津、茅草枯每公顷施用量分别为1.2,3.5和6公斤时。能够抑制野生植物70—90%,但不能抑制蚜虫和红蜘蛛。当氯苯胺灵浓度为1.2%,草克死和菌达灭均为0.4%时,对吮吸口器害虫毒杀效果最好,可达90%以上。     

缓释缩节胺包衣处理对棉花农艺及经济性状的调控效果

研究了缓释缩节胺和杀虫剂包衣、使种子亚丸粒化技术在棉花上的应用效果 ,结果表明 ,缓释缩节胺包衣处理的株高、主茎节间长度和果节数不同程度地减少 ,单株生产力随株高的降低明显下降。不同缓释材料间引起的差异一般大于不同缩节胺剂量间的差异。在缓释缩节胺中添加杀虫剂还可大大减轻棉花的苗期虫害。     

三种热雾剂对橡胶树炭疽病大田防治试验

田间试验比较10％百菌清、20％氟硅唑·咪鲜胺、16％百菌清·咪鲜胺·三唑酮三种热雾剂对大田橡胶树炭疽病的防治试验结果,其中前两种处理防效（相对防效68．14％和66．31％）显著优于16％百菌清·咪鲜胺·三唑酮和对照处理。     

保健灵身茶——一种新的保健茶

江西省婺源县是我国著名的绿茶产地,所产“婺绿”品质特优,是我国历史上出口绿茶中品质最优者。由于该地区山高林茂、土壤肥沃、云雾多,因此茶叶质地肥嫩,香高味醇,水浸出物含量高,内含营养成分和药效成分丰富,是理想的保健茶基料。 中外合资江西婺绿保健茶有限公司新创制的保健茶——“保健灵身茶”,就是以高档“婺绿”作基料,配以绞股兰和野生葛根等名贵中草药提取物,经科学精制而成。这种保健茶富含维生素C和其他各种维生素,胡萝卜素含量达4.71mg/100g,还含有多种矿物质     

防治水稻恶苗病药剂筛选试验

对防治恶苗病不同杀菌剂进行药剂筛选试验,结果表明,25%噻虫·咯·霜灵FSC 2.5 ml/kg处理种子及23%吡虫·咯·苯甲FSC 5 ml/kg处理种子,不仅秧苗素质高,而且对水稻恶苗病防效也高,秧田防效分别为95.8%、93.4%,本田防效均为100%,明显高于对照药剂25%咪鲜胺EC和空白对照,对水稻生长具有良好的安全性。     

花生抗黄曲霉侵染主微效基因分析

采用主-微效基因混合遗传模式,分析了花生抗黄曲霉侵染的遗传规律。结果表明花生对黄曲霉侵染的抗性是由一对主基因和一对微效基因控制。主效基因和微效基因均以加性效应为主,无显性效应。主基因、微效基因加性效应值分别为0.38和0.12。     

多效唑和缩节胺对不同生长势马铃薯生长和产量的影响

<正> 多效唑PP_(333)是一种新型植物生长调节剂,已广泛应用于水稻、小麦、大豆、油菜、烟草、甘薯等作物上,在马铃薯上的应用也曾有报道,一致认为多效唑强烈抑制马铃薯地上部生长、促进光合产物向块茎运输、从而增加产量的效应.缩节胺(DPC)为棉花生产大量应用的一种植物的生长延缓剂,在马铃薯上的应用还未见报道.本文分析了多效唑和缩节胺对不同生长势马铃薯的生长及产量的影响结果,旨在促进植物生长延缓剂在马铃薯生产中的合理使用.     

抗精噁唑禾草灵耿氏硬草乙酰辅酶A羧化酶基因研究

为明确耿氏硬草抗性种群SD-23对乙酰辅酶A羧化酶(ACCase)抑制剂类除草剂的抗性水平及靶标抗性分子机理,采用整株水平测定法测定了SD-23种群对6种ACCase抑制剂类除草剂的抗性,扩增和比对了抗性和敏感种群间的ACCase基因序列,并测定了耿氏硬草种群SD-23对其他4种除草剂的敏感性。结果表明,SD-23种群对精噁唑禾草灵产生了高水平抗性,抗性倍数为12.7,对炔草酯和精吡氟禾草灵产生了低水平抗性,抗性倍数分别为5.2和4.5,对烯禾啶、烯草酮和唑啉草酯较敏感。与敏感种群SD-1相比,SD-23种群ACCase的CT区域第2096位甘氨酸突变为丙氨酸(Gly-2096-Ala);甲基二磺隆、啶磺草胺和异丙隆对抗性和敏感种群均有较好防效,其防效达86.7%以上,干重防效达77.4%以上。ACCase的Gly-2096-Ala突变第一次在耿氏硬草中被报道,该突变可能是导致SD-23种群对精噁唑禾草灵产生抗性的重要原因之一。     

15%嘧咪酮热雾剂防治橡胶树白粉病田间试验

报道了几种高扬程药剂对橡胶树白粉病的防治效果。供试的杀菌剂有15%嘧咪酮热雾剂和15%粉锈宁烟雾剂、硫磺粉、15%咪鲜胺·腈菌唑烟雾剂等6种,不同杀菌剂用相匹配的植保机械施药。施药2次,根据施药后10 d的调查结果比较防效,15%嘧咪酮热雾剂的防效最好,15%粉锈宁热雾剂药效最差。且施药后10 d的调查数据显示,15%嘧咪酮热雾剂施药2次的防效优于硫磺粉施药3次,表明15%嘧咪酮热雾剂的持效期要优于325目硫磺粉。     

利用植物疫苗及生长调节剂缩节胺控制棉花黄萎病

2008-2009年于棉花黄萎病重病田研究了植物疫苗渝峰99植保、激活蛋白、氨基寡糖素单独使用及与植物生长调节剂缩节胺混合使用对棉花黄萎病的防治效果,并选择激活蛋白和缩节胺混合施用研究了不同施药时间和施药次数对棉花黄萎病的防治效果。结果表明:渝峰99植保、激活蛋白、氨基寡糖素和缩节胺单独使用,以缩节胺防治效果最好(平均防效41.3%),其次是激活蛋白(平均防效36.7%)。3种植物疫苗和缩节胺混合使用均可不同程度地提高防治效果,渝峰99植保+缩节胺、激活蛋白+缩节胺、氨基寡糖素+缩节胺的平均防效分别为52.9%、52.2%、47.9%。在2个棉花品种上的试验结果均表明,于5月30日开始用药,每10天1次,连续用药3次,间隔20～30天再用药1～2次,对黄萎病的控制效果最好。     

Sprout inhibition in storage: Current status, new chemistries and natural compounds

A major component of managing potato quality in storage is effective sprout inhibition. Sprouting causes increased weight loss, reduced tuber quality and impedes air movement through the potato pile. The primary method to control sprouting in storage is with postharvest applications of isopropylN-(3-chlorophenyl) carbamate (chlorpropham; CIPC). CIPC inhibits sprout development by interfering with cell division. However, a recent Environmental Protection Agency mandate, from the requirements of the Food Quality Protection Act (FQPA) of 1996, resulted in a reduction in allowable CIPC residue on fresh potatoes in the United States from 50 ppm to 30 ppm. This mandate coincides with tolerance reductions or restrictions for use of CIPC in other parts of the world. CIPC is an effective sprout inhibitor although factors such as storage conditions, application technology, and cultivar can impact that effectiveness. Alternative sprout inhibitors to CIPC continue to be evaluated. Essential oils (e.g., caraway, peppermint, spearmint, clove) or their components (e.g., s-carvone, eugenol), and hydrogen peroxide-based materials, physically damage the developing sprout and suppress sprout elongation. However, repeated or continuous application of these compounds may be necessary for efficacy. Substituted naphthalenes (e.g., dimethyl naphthalene, diisopropyl naphthalene) may help reduce the amount of CIPC applied and/or our dependency on CIPC for sprout suppression in storage. The objective of this review is to summarize the current use of CIPC for potato sprout inhibition in storage and to review the status of current research on other postharvest applied compounds or materials that may be used as alternatives for CIPC.     

Using Ethylene Gas and Chlorpropham Potato Sprout Inhibitors Together

Marketplace preference for lower pesticide residues in foods has led to research to reduce the residue of chlorpropham (isopropyl N-3-chlorophenyl carbamate; CIPC), a postharvest-applied sprout inhibitor which is widely used around the globe to prevent sprouting of stored potatoes (Solanum tuberosum L.). Ethylene gas, an effective, safe and non-toxic sprout inhibitor used in several countries, sometimes has negative effects on the colour of processed potato products when used alone. Trials were conducted over 3 years using cv. Shepody (French fry) and cv. NorValley (potato chips/crisps) to determine whether a combination of these two sprout inhibitors, at reduced dosages, could inhibit sprouting while maintaining good processing colour. CIPC applied at 0, 0.1, 0.25 and 1.0 times the recommended dosage was combined with 4 μll⁻¹ of ethylene gas applied or no ethylene at all (0 ethylene), for 1 day in 4 days, for 1 day in 2 days or continuously, in a factorial design. Sprout inhibition in both cultivars was excellent at all levels of CIPC application except the 0 rate. In both cultivars, sprouting was inhibited by the continuous ethylene treatment. However, all levels of ethylene exposure except the 0 rate negatively affected processing colour in both cultivars. The darkening was dose dependent, whereby the colour was darkest in continuous ethylene and was less affected by the intermittent exposures. In continuous ethylene, the colour was progressively lighter during storage after initial darkening. Shepody tubers appeared to be more sensitive to ethylene than the NorValley tubers. In Shepody only, colour in the ethylene of 1 day in 4 days treatments was progressively darker with increasing time in storage.     

Effects of chlorpropham (CIPC) on sprouting of individual potato eyes and on plant emergence

The sprout inhibitor chlorpropham (CIPC) was applied in varying concentrations to individual eyes of potato tubers. Sensitivity of a given eye to CIPC depended upon the status of the remaining eyes on the same tuber. If the remaining eyes were inhibited, higher concentrations of CIPC were required for inhibition of the given eye. Apical eyes were more sensitive to CIPC than were lateral eyes. It was confirmed that CIPC is highly volatile and that contaminating levels of CIPC vapors can induce a rosette sprout growth. Seed potatoes treated with low concentrations of CIPC before planting sprouted more slowly than untreated potatoes, and the delay was related to CIPC concentration. At high CIPC levels, total emergence as well as rate of emergence was reduced. However, emergence was far greater than would have been anticipated from the sprouting of similar treated lots held in storage.     

Auxin-induced sprout growth inhibition: Role of endogenous ethylene

The role of endogenous ethylene in auxin-mediated tuber sprout growth inhibition was determined in potato (Solanum tuberosum L. cv. Russet Burbank) minitubers. Treatment of tubers with biologically active auxins resulted in a transient, dose-dependent increase in ethylene production and inhibition of sprout growth. Biologically inactive auxin analogs elicited neither response. Continuous exposure to > 0.001 μL L^-1 exogenous ethylene inhibited sprout growth in a dose-dependent manner with complete inhibition occurring at ethylene concentrations ≥1 μL L^-1. In further studies with the active auxin α-naphthalene acetic acid (NAA), the role of ethylene in auxin-induced sprout growth inhibition was determined using ethylene biosynthesis and action inhibitors. The ethylene biosynthesis inhibitor aminoethoxyvinylglycine reduced NAA-induced ethylene biosynthesis by over 80% but had no effect on sprout growth inhibition. The non-competitive ethylene action inhibitor silver thiosulfate had no effect on NAA-induced sprout growth inhibition. Similarly, both the competitive ethylene action inhibitor 2,5-norbornadiene and the irreversible action inhibitor 1-methylcyclopropene were ineffective in reducing NAA-mediated sprout growth inhibition. Collectively, these results do not support the proposal that, in the case of potato tuber sprouts, auxininduced growth inhibition is mediated by endogenous ethylene action.     

Comparison of sensory differences of stored Russet Burbank potatoes treated with CIPC and alternative sprout inhibitors

The sensory properties of Russet Burbank potatoes treated with three naturally occurring volatile compounds, as alternatives to CIPC for sprout inhibition, were evaluated. Potatoes from the 1995 and 1996 crop years were treated with salicylaldehyde, 1,8-cineole, 1,4-dimethylnaphthalene, or CIPC prior to dormancy break during storage and stored for up to 16 wk. Sensory differences between potatoes treated with alternative sprout inhibitors and CIPC-treated or untreated potatoes and inhibitor concentration were determined at 2-wk intervals. Potatoes treated with 1,8-cineole or salicylaldehyde, but not 1,4-dimethylnaphthalene, were significantly different from the untreated potatoes or potatoes treated with CIPC. Sensory detection threshold levels for the alternative inhibitors were measured in a model potato system. The residual levels of the sprout inhibitors were within the detection threshold range for 1,8-cineole (0.02–0.04 ppm), but not for salicylaldehyde (0.0–0.10 ppm) or 1,4-dimethylnaphthalene (0.80–1.40 ppm). The presence of the residual sprout inhibitors and/or the influence of sprout inhibitors on potato metabolism during storage contributed to observed differences in sensory quality of stored potatoes.     

Potato Sprout Growth Suppression by Menthone and Neomenthol, Volatile Oil Components ofMinthostachys, Satureja, Bystropogon, andMentha Species

The replacement of synthetic pesticides such as chlorpropham (CIPC) with effective potato sprout suppressants that have negligible environmental impact is needed due to increased concern for consumer health and safety. To date, however, only S-(+)-carvone, a monoterpene produced from caraway seeds, has been developed commercially as a competitive product to CIPC. Consequently, the effects of menthone and neomenthol vapor were compared to S-(+)-carvone for sprout suppressant efficacy as well as for effects on soluble sugar levels, respiration, and processing quality during high and low temperature storage. In the majority of treatments, tubers were enclosed in 3.8 1 glass jars at 25 C. Liquid test compounds were applied to a 10-cm-long x 2-cm-wide filter paper strip (Whatman No. 1) enclosed in each jar. Treatment with either menthone or S-(+)-carvone at 5 ul liquid/1 of treatment volume gave complete sprout suppression in non-dormant Russet Burbank tubers. An examination of changes in CO₂ output, glucose, or sucrose levels over 4 wk at 10 C indicated that the effects of menthone and S-(+)-carvone were similar. In addition, menthone significantly inhibited sprouting without adversely affecting the percentage glucose content or sucrose content when this compound was applied at 4 ul/l to five-month-old, non-dormant tubers of AC Novachip, Russet Burbank, Shepody, and Snowden for two months at 10 C. Menthone and neomenthol were five to ten times more effective in sup pressing tuber sprouting than S-(+)-carvone when applied together at 0.5 ul/l each.     

Persistence of Chlorpropham (CIPC) in the Concrete Flooring of Potato Stores

The loss of the sprout suppressant, chlorpropham (CIPC), to the fabric of potato stores is currently of concern due to the risk of potential cross contamination of other crops subsequently housed in these stores. HPLC UV/VIS and GCMS methods were successfully employed to detect CIPC in the concrete flooring of research and commercial potato stores with histories of between 1 and 26 years of use. The concentrations in identical research stores, with different numbers of applications, were in the range 0.58–5.7 and 3.4–112 μg g^?1, suggesting the magnitude of contamination was influenced by the number of applications. Commercial store A, with a history of 18 seasons of applications (estimate of total CIPC applied 2040 kg), had concentrations varying between 6 and 48 μg g^?1 in the top three centimetres, with more than 92% within the top centimetre. In contrast, commercial store B, with a history of less than five seasons of applications (estimate of total CIPC applied 319 kg), had concentrations varying between 0.58 and 304 μg g^?1 in the top four centimetres, with less than 47% within the top centimetre. The difference in depth distributions between A and B may be due to the structural integrity of the concrete, which was much poorer in B. CIPC was persistent in all stores irrespective of the total quantities of CIPC applied and date of the final application.     

Slug damage and control of field slug (Deroceras reticulatum (Müller)) by carvone in stored potatoes

Summary After a wet autumn and harvesting under wet conditions, slugs brought into potato stores via clods and soil adhering to tubers may cause substantial damage by feeding on the tubers. A carvone sprout inhibitor, Talent^?, applied in the potato stores at a dose of 50 ml per tonne potatoes, controlled slugs within a few days. A dose of 25 ml carvone was insufficient. Using a laboratory box test, the slug (Deroceras reticulatum) affected only wounded tubers and, although slime was present on the unwounded potatoes, they were not damaged by slugs.     

Dimethylnaphthalene and diisopropylnaphthalene for potato sprout control in storage: 1. Application methodology and efficacy

Dimethylnaphthalene (DMN) and diisopropylnaphthalene (DIPN) isomers applied as sprout suppressants to stored potatoes (cv. Russet Burbank) were evaluated for effects on sprout length and weight compared to chlorpropham (CIPC). One application of CIPC at 22 mg a.i. kg^-1 of tuber fresh weight (f.w.), and one or two applications of DMN and DIPN at 100, 200, and 300 mg a.i. kg^-1 f.w. were applied as thermal aerosol fogs. Two applications of DIPN at 300 mg a.i. kg^-1 f.w. were as effective as CIPC in suppressing sprout growth during ten months of storage. DMN also suppressed tuber sprout growth but was not as effective as two applications of DIPN or one application of CIPC. One application of DIPN or DMN at 300 mg a.i. kg^-1 f.w. was an effective suppressant of sprout growth on a short-term basis. Whole tuber residue analyses were also conducted. After ten months in storage, DMN and DIPN residue concentrations were equal to or less than those of CIPC.     

The Combined Effect of CO2 and Ethylene Sprout Inhibitor on the Fry Colour of Stored Potatoes (Solanum tuberosum L.)

Recently, it has been shown that the darkening of potato processing colour attributable to a trace concentration of ethylene gas is more severe when CO₂ is also elevated. In view of the increasing use of ethylene gas for sprout suppression in potato storage facilities, it was considered important to determine whether this effect also occurs at the much higher ethylene concentration used in commercial practice. Sprouting and processing colour of the French fry cultivars Russet Burbank, Shepody and Innovator and the potato crisp cultivar Dakota Pearl were tested during the November to June storage season of two consecutive years. Treatments were 0 or 2 kPa CO₂ and 0 or 10 μL?L^?1 ethylene in a factorial design, plus a chlorpropham check. The 0 CO₂?+?0 ethylene treatment constituted an untreated control. The ethylene exposure was commenced abruptly to maximize its effect on colour. The main effect of ethylene resulted in darker processing colour in all cultivars, whereas darkening attributable to the main effect of CO₂ was observed only in Innovator and Dakota Pearl. The statistical interaction of the CO₂ and ethylene was not significant except in Dakota Pearl Hunter a (redness) scores, although a tendency to darker colour when both gases were present was seen in Russet Burbank and Innovator at all evaluation dates. The results indicate that both gases can affect processing colour when ethylene is used to control sprouting, although considerable variability in the response exists among cultivars. This variability in combination with management of storage conditions such as temperature and CO₂ can be utilized to minimize the impact of these gases on the processing colour of stored potatoes.