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水稻白叶枯病抗性杂种优势 总被引：2，自引：0，他引：2
本试验采用双列式杂交方法,观察了以IR26、IR36等为代表的抗性品种的杂交优势。结果表明:杂交组合F1代在分蘖末期抗性无优势,穗期抗性优势明显;F2代两期鉴定正负向均有优势;F1和F2代均表现出正负向完全显性,部份显性,少数组合无显性。其中大都属于部份显性。优势指数分析也证明,对抗性亲本,优势指数d ≥ 1;对感病亲本,优势指数d<1。抗感品种杂交,其子代的抗性一般界于双亲值之间。这种优势可依亲本的抗性进行预测。 相似文献
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酿酒高粱品种、组合及亲本的丝黑穗病抗性鉴定 总被引：1，自引：0，他引：1
为了明确不同类型的酿酒高粱材料对西南地区丝黑穗病的抗性和促进抗丝黑穗病品种的选育,采用土壤接菌法对107份材料进行了丝黑穗病抗性鉴定;根据抗性鉴定结果,比较了酿酒高粱杂交组合与其亲本对丝黑穗病的抗性,并对供试菌种进行了致病力分析.结果显示:在感病对照恢1植株平均病株率为67.65％时,有13个不育系、6个保持系、10个恢复系、28个杂交组合的病株率为0,达免疫水平,其中,酿酒高粱不育系和杂交组合所占比例较大,分别为86.67％和75.68％;恢复系中免疫类型所占比例较小,为24.39％;常规品种和组合中无免疫类型;杂交高粱对丝黑穗病的抗性属显性遗传;泸州丝黑穗病菌具有较强的致病力. 相似文献
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为明确云南籼稻主栽品种对白背飞虱Sogatella furcifera(Horváth)的抗虫性及其影响产量的水稻关键生育期,为抗虫品种选育和推广提供参考依据,本文利用苗期和分蘖盛期单株接虫鉴定、成株期(移栽期—乳熟期)田间自然种群发生鉴定等方法,测定了云南籼稻区31个水稻主栽品种对白背飞虱的抗虫性及其产量。结果表明,苗期有7个品种表现高抗,23个品种表现中抗—中感,1个品种表现高感;分蘖期有20个品种表现高抗,有11个表现中抗—中感;成株期田间自然种群鉴定,31个品种成株期白背飞虱田间自然种群的累计虫量都超过了对照品种TN1,均表现为感虫。单株接虫鉴定多数品种表现抗虫,而大田期自然种群鉴定则全部表现为感虫,一定程度说明了云南籼稻区主栽品种对白背飞虱具有耐害性而无抗生性。移栽期、孕穗期、抽穗期百丛虫量与有效穗数呈显著的负相关性;移栽期、孕穗期和抽穗期的百丛虫量是造成有效穗数少和产量低的关键因子。移栽期、孕穗期和抽穗期是防治白背飞虱的关键时期。 相似文献
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广西普通野生稻种质资源抗褐稻虱鉴定 总被引：2，自引：0，他引：2
经多次重复筛选鉴定，发现广西普通野生稻的一些编号对褐虱具有抗性和耐性，同时通过抗性苗继代自交和抗性鉴定，获得一批抗性纯合材料，扩大和丰富了抗源的多样性，为选育抗虫品种提供了宝贵的亲本。 相似文献
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广东水稻品种对不同白叶枯病菌株的抗性反应 总被引：1，自引：0，他引：1
测定了46个水稻品种对60个菌株的抗性反应,可以将这些品种区分为Ⅰ、广谱性抗病,Ⅱ、非广谱性抗病及Ⅲ、无抗性等三种类型。Ⅰ类型品种大多数是外引品种及其杂交衍生品种(系)。Ⅱ类型品种中只有少数具有较好的抗性,大多数都是中等抗病与中等感染的。Ⅲ类型品种都是偏于感病的,但丰产性状较好。为育成更多的抗病新品种,我们认为选择具有广谱抗性的品种作为亲本与高产品种进行组配,另外选择1—2个强菌株作为抗源筛选或杂交组合子代的抗性鉴定菌株,以获得满意的结果。 相似文献
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我国棉花品种(系)抗虫性的鉴定、选育与应用 总被引：9，自引：0，他引：9
棉铃虫的暴发为害已严重制约了我国棉花生产的稳定发展,生产上急需在综合防治中利用棉花自身的部分抗虫性抵御害虫的侵害,提高植棉的综合效益。本文从棉花种质(材料)的外部形态抗虫性、生理生化抗虫性、外源性抗虫基因导入等三个方面详细讨论了我国棉花品种(系)的抗虫性鉴定、选育及其研究进展现状。针对抗虫棉研究与利用中存在的若干问题,探讨了未来发展的方向。 相似文献
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红铃虫危害棉株蕾花引起蕾、花、铃脱落,对结铃和产量有无影响进行系统的观察。经三年试验获得一致的结果,红铃虫危害棉株蕾花所引起的脱落,对棉株结铃率影响无显著差异;对棉株结铃数和产量影响也无显著差异。因此,第一代红铃虫田间可省去施药、摘虫花和花心捉虫等防治措施,减少繁琐的劳动,有利于保护棉虫天敌,维持生态平衡,控制棉蚜和棉铃虫等害虫的发生危害。 相似文献
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BACKGROUND: The pink bollworm is one of the most destructive pests of cotton. Transgenic cotton producing Bt toxin Cry1Ac or a combination of Cry1Ac and Cry2Ab2 has been used effectively against this pest. However, some other insects have evolved resistance to Bt toxins in the field. During the 2007–2008 and 2008–2009 seasons, pink bollworm populations in India were surveyed to evaluate their responses to Cry1Ac and seed powder containing Cry1Ac and Cry2Ab2. RESULTS: The results provide evidence that resistance to Cry1Ac had evolved by 2008 in a population sampled from non‐Bt cotton in the Amreli district of Gujarat in western India. The median lethal concentration of Cry1Ac for five‐day‐old larvae (LC50) was significantly higher for insects derived in 2008 from Amreli than for any of the other field populations tested from four locations in India. For Cry1Ac, the mean LC50 for the strain derived from Amreli in 2008 was 44 times higher than for the most susceptible population. However, for seed powder of Bollgard II containing primarily Cry2Ab2, the 2008 Amreli population was only slightly less susceptible than the most susceptible population. CONCLUSIONS: The data reported here constitute the first evidence of field‐evolved resistance of pink bollworm to Cry1Ac. This initial evidence spurred more extensive evaluations during the 2009–2010 growing season, which confirmed field‐evolved resistance to Cry1Ac in Amreli. The lack of cross‐resistance to Cry2Ab2 suggests that plants producing this toxin are likely to be more effective against resistant populations than plants producing only Cry1Ac. Copyright © 2011 Society of Chemical Industry 相似文献
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应用主成分分析方法,综合评价了54个棉花种质铃期(棉红铃虫二代)和吐絮期(棉红铃虫三代)的抗性,结果抗性种质分别有9个(占16.7％)和4个(7.4％),感性种质分别有15个(27.8％)和28个(51.9％),其它属于中间类型。比较种质铃期和吐絮期对棉红铃虫的抗性,铃期抗性表现随棉红铃虫的世代延续,种群数量增大,呈不稳定性。鉴以吐絮期抗性表现是在当年棉红铃虫种群压力最大时的结果,因此认为,抗性鉴定以吐絮期为适。综合指标(又称主成分)能更好地发现和评价种质的抗虫性,但进一步作抗性分级须继续探索。 相似文献
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冀南棉麦混作区棉花害虫综合防治技术的研究 总被引：3，自引：0，他引：3
1983—1985年在河北南部棉麦混作棉区设点,进行了以棉蚜、棉铃虫为主要对象的综合防治技术研究。从棉田生态系的整体出发,根据棉花、害虫与天敌各主要组成成份的特点及相互关系,尽可能利用自然因素,设计了以棉麦邻作布局、种子处理、棉田内分阶段衔接种植诱集植物油菜——春玉米——夏玉米来保护增殖自然天敌、制订合理防治指标、减少用药和加强棉田栽培管理、种植抗病品种等配套技术的农业防治、生物防治和化学防治相结合的综合防治措施,经3年来多点大田试验、示范、应用,结果表明在控制虫害、减少用药、保护增殖天敌、降低防治成本等方面效益明显。 相似文献
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W. R. Ingram 《国际虫害防治杂志》2013,59(2):118-137
Abstract Barbados once grew large amounts of Sea Island cotton but the accidental introduction of pink bollworm (Pectinophora gossypiella) in the 1920s, falling prices and rising costs led to the collapse of the industry. Falling sugar prices subsequently led to a revival of interest in the crop but pink bollworm still presented a problem and warranted investigation. The synthetic sex pheromone of pink bollworm, gossyplure, was shown to attract far more males than hexalure or virgin females. Sticky traps needed stirring daily and were only able to catch about 50 males a night. Water, with a drop of liquid detergent, proved to be a suitable trapping medium and was cheaper than liquid paraffin although not quite as effective. The best type of trap from materials readily available was one made from a plastic half gallon ice cream container with lid and holes cut around the upper sides. Traps without the attractant caught very few moths. Gossyplure adsorbed onto rubber caps was attractive to pink bollworm males for over 56 days but the half-life appeared to be about 28 days. Best catches were obtained in cotton when the traps were suspended just below the tops of the plants and, within fields, traps at the leeward end caught more than traps elsewhere. Peak catches of males occurred before midnight in a black light trap whereas pheromone traps caught no males before midnight but peaked at 03.00h. A close season during which no cotton is allowed to grow is a recognised means of reducing pink bollworm carryover between crops. This was practised in Barbados but island-wide pheromone trapping showed that moths were caught throughout the close season. This continuous trapping of moths indicated that pink bollworm must be breeding (short-cycle) in order to survive. Trapping and laboratory studies confirmed the presence of long-cycle pink bollworm which entered diapause towards the end of the cotton season as daylength increased. This diapause terminated with shortening days after the new season's rains commenced. The case for a four month close season is discussed. Pheromone trap catches were shown to be very closely correlated with boll damage. Catches of 8–9 moths in a night represented a 10% level of boll damage some ten days later and this is the trapping level at which cotton growers are advised to begin insecticidal treatment. Thorough residue destruction is the key to a good close season and a suitable method was needed for use under Barbadian conditions. The method finally chosen and proved on an estate scale was to cut down the standing cotton with a horizontal-rotary chain slasher, driving across the rows of cotton, the debris was then raked along the rows, stacked and burnt and finally the stumps were ploughed in, again across the rows. The parasite Perisierola nigrifemur is very common in pink bollworm larvae towards the end of the season but too late to be of economic value. Predation of diapausing larvae by the mite Pyemotes ventricosus is very common at the end of the cotton crop and during the close season. Insecticidal application in Sea Island cotton which usually grows very tall (> 1.75m) and rank is best achieved with hand-held, battery-operated, u.l.v. sprayers. Control of pink bollworm can be obtained with carbaryl S formulations applied through these sprayers with the addition of a little water and molasses. Synthetic pyrethroids in u.l.v. formulations are also expected to provide control. 相似文献
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新疆地区棉铃虫自然种群对Bt棉的抗性频率监测 总被引：1，自引：0，他引：1
为监测新疆棉区棉铃虫Helicoverpa armigera(Hübner)田间种群对Bt棉的抗性频率,在2010年和2011年分别采集石河子和喀什地区莎车的棉铃虫单雌系,以Cry1Ac毒蛋白作为人工饲料,用单雌系F1/F2代法进行棉铃虫种群抗性个体检测。2010年筛选了123个石河子的棉铃虫单雌系,2 011年筛选了152个莎车的棉铃虫单雌系。两地的棉铃虫种群均没有筛选到相对平均发育级别≥0.8的抗Bt棉个体,估算出石河子和莎车的棉铃虫种群的抗性频率低于10-3。莎车F2单雌系与其对应的F1单雌系相对平均发育级别有明显差异。研究表明新疆石河子地区田间棉铃虫种群仍保持敏感状态,喀什地区田间棉铃虫种群对Bt棉的耐受性增高。 相似文献