春小麦抗蚜性与麦长管蚜EST活性及GSH活性的关系

为阐明春小麦对蚜虫的抗生性机理及蚜虫对寄主的适应性机制,选用抗蚜性不同的8个春小麦品种（系）为试验材料,利用灌浆期人工接种的方法,研究了小麦抗蚜水平与麦长管蚜无翅型孤雌胎生蚜酯酶（EST）活性及谷胱甘肽转移酶（GSH）活性的关系。结果表明,蚜虫EST活性与春小麦抗蚜水平有关,GSH活性与小麦抗蚜水平无关。穗部及旗叶蚜虫EST活性均与其存活率呈显著负相关,相关系数分别为-0.7047（P=0.04523）和-0.7214（P=0.0380）,与有翅蚜分化率接近显著或显著负相关,相关系数分别为-0.6767（P=0.05911）和-0.7317（P=0.0336）,与仔蚜繁殖率相关不显著。穗部及旗叶上蚜虫GSH活性均与其存活率、有翅蚜分化率及仔蚜繁殖率不相关。     

抗虫小麦对麦长管蚜发育和繁殖的影响

为了观察植物抗性压力对麦长管蚜（Ｓｉｔｏｂｉｏｍ ａｖｅｎｕｅ Ｆａｂｒ．）繁殖的影响，本文研究了蚜虫在抗性小麦品种和敏感小麦品种上从出生到死亡的寿命、繁殖、成虫重量及生殖腺状态；还研究了无翅蚜在两类品种间的迁移状况。将这种结果与若虫期或成虫期饥饿１０或１４ｈ后的蚜虫所获参数进行了比较。用成虫做试验的抗性植株与用幼虫做试验的同一植株所测得的每一参数极为不同，在抗性小麦上生长和繁殖的蚜虫与受半饥饿影响     

小麦种质资源的抗蚜性及其与表型性状的关系

为了筛选抗蚜虫的小麦种质资源以及获得小麦抗蚜性选择的形态学指标，2002～2005年对国内外4600份小麦种质资源进行了田间抗蚜性鉴定，并对其中40份抗蚜性不同的材料的抗蚜性与表型性状的关系进行了研究。抗蚜性鉴定结果表明，参试材料的抗蚜性存在明显差异，分为高抗、中抗、低抗和不抗四种类型。筛选出抗蚜材料30份，占参试材料的0．65％，其中C273（印度）和兰麦（陕西柞水）表现高抗，其余7份和21份材料分别表现中抗和低抗。40份不同抗蚜性材料的抗蚜性与表型性状的相关研究表明，植株蜡粉与蚜量比值呈极显著正相关，颖壳颜色与蚜量比值呈显著正相关，穗密度与蚜量比值呈显著负相关，旗叶长、宽及长宽乘积、叶色、芒长、颖壳茸毛等与蚜量比值无显著相关性。颖壳颜色、蜡粉和穗密度可以作为小麦抗麦长管蚜选择的辅助指标。     

146个小麦品种(系)对小麦黄花叶病毒病的抗性分析

为明确黄淮麦区不同小麦品种（系）对小麦黄花叶病毒病的抗性水平,2016—2017年度在河南省漯河市两个重病田块对146个小麦品种(系)进行了小麦黄花叶病毒病的抗性鉴定,并对不同抗性级别小麦的株高、株成穗数、穗粒数和千粒重进行了分析。结果表明,供试材料中,检测到存麦16号、才智141和众麦7号等免疫品种（系）12个,占鉴定材料的8.2%;检测到郑麦366、周麦26、郑麦119等高抗品种（系）37个（25.3%）;中抗、中感和感病品种（系）分别有28个（19.2%）、42个（28.8%）和27个（18.5%）。小麦黄花叶病毒病对小麦株高、株成穗数、穗粒数和千粒重均有显著影响。高抗组、中抗组、中感组和感病组平均株成穗数较免疫组减少了4.01%、24.55%、33.41%和38.34%;以免疫组为基准,得到各组株高校正偏离率分别为 -0.71%、-6.16%、-8.82%和-11.72%;穗粒数校正偏离率分别为-0.66%、-13.61%、-23.33%和 -26.40%;千粒重校正偏离率分别为-3.00%、-4.79%、-7.73%和-8.83%。     

小麦品种对禾谷孢囊线虫（Heterodera avenae） 江苏沛县群体的抗性鉴定

为了筛选对禾谷孢囊线虫病(Cereal cyst nernatode,CCN)具有抗性的小麦品种,采用室内二龄幼虫接种法、网室卵接种法和田间病圃法测定了收集自5个省份的40个小麦品种对小麦孢囊线虫江苏沛县群体的抗性。室内二龄幼虫接种测定结果表明,供试材料中无免疫品种,华麦1号、温粮58和豫麦66-18系表现为高抗,扬麦13和徐麦7086表现为中抗,烟农5158表现最感病,平均单株白雌虫数达104.7个;田间病圃测定表明,上述5个品种仅华麦1号表现为抗病。网室卵接种法测定结果与室内二龄幼虫接种法及田间病圃法测定结果差异较大,显示该方法不适用小麦品种的CCN抗性鉴定。     

稻蟹田与常规稻田蚜虫发生动态数学模型

为进一步明确麦长管蚜在盘锦地区的发生与环境因子之间的关系,以及在2类稻田的发生危害情况。在系统调查麦长管蚜种群动态的基础上,利用多元回归法,得到麦长管蚜与环境因子间的数学模型,以及2类稻田上的发生分布情况。结果表明：盘锦地区2类稻田上发生危害的均为麦长管蚜;麦长管蚜在2类稻田的发生时间动态一致;在水稻穗上部分布比例约为80%,全株蚜量（y）与穗上部蚜量（x）之间的关系,常规田：y=1.25x+2.55,稻蟹田：y=1.19x+1.41;常规田麦长管蚜的发生与当地近7日平均温度存在显著的相关性。     

不同燕麦品种(系)对麦二叉蚜生命参数的影响

为比较具有不同抗蚜性的燕麦品种对麦二叉蚜连续2个世代若蚜和成蚜主要生命参数的影响,在室内22℃条件下,采用网罩法对UFRGS105064-3等8个具有不同抗蚜性的燕麦品种(系)上的若蚜发育历期、存活率和成虫寿命、生殖力等生命参数进行了观测,组建了麦二叉蚜实验种群生命表。结果表明,不同燕麦品种(系)对麦二叉蚜若蚜发育历期和成蚜生殖力有显著影响,在抗蚜性强的品种(系)上,麦二叉蚜若蚜发育历期延长,成蚜产仔量减少;以内禀增长率作为测定抗生性的指标,供试燕麦品种(系)中,UFRGS105064-3、燕2007和白燕2号的抗生性最强,其次为MF9715,QO245-7、OA1251-1、108C105和UFRGS097018-3抗生性较差。通过对比不同世代的蚜虫生物学参数发现,抗蚜品种(系)对蚜虫下世代抗生性的影响存在加重现象,抗生性在蚜虫世代间可能存在累加效应,并且这种影响随着燕麦抗性的升高而加重。     

小麦禾蚜抗源探索

小麦育种在蚜虫抗性方面明显落后的主要原因之一是对原始材料研究的较少.分析国内资料表明,主要禾谷类作物抗蚜性资料不完备,研究较多的仅是苏联欧洲部分南方冬性普通小麦对麦长管蚜(Sitobion av-     

2016-2017年陕西省小麦区试品种（系）综合抗病性鉴定与评价

为了解2016-2017年陕西省区试的137份小麦品种(系)对条锈病、白粉病和赤霉病的综合抗病水平,以当前我国小麦条锈病主要流行小种CYR32、CYR33和CYR34混合菌株、小麦白粉菌混合菌株和小麦赤霉病强致病力菌株为病原,对区试品种(系)进行成株期人工接种鉴定。结果表明,137份区试材料中,有2份材料对条锈病、白粉病和赤霉病兼具抗性,占供试材料的1.5%,分别为西农238和西农928;6份材料对条锈病和白粉病兼具抗性,占供试材料的4.4%;对条锈病、白粉病和赤霉病表现高抗的材料（含免疫/近免疫）分别占供试材料的34.3%、2.9%和0.7%,中抗品种分别占35.0%、4.4%、33.6%,中感品种分别占21.9% 、8.0% 、30.7%,高感品种分别占8.6%、84.7%、35.0%。陕西省区试小麦品种（系）对条锈病的抗性整体较高,对白粉病和赤霉病的抗性相对较差。     

小麦新品种(系)对麦红吸浆虫抗性的鉴定与分析

为了寻找抗吸浆虫的小麦品种或种质材料,采用田间自然鉴定法鉴定了90份小麦新品种(系)对麦红吸浆虫的抗性,结果表明,不同小麦品种(系)对麦红吸浆虫具有明显的抗性差异。对各种类型的材料分析表明,对麦红吸浆虫表现高抗、中抗、低抗、感虫类型的小麦品种(系)分别占参试品种(系)的4.44%、15.56%、61.11%、18.89%。不同小麦品种(系)具有不同的抗虫性,其单穗虫数、穗被害率、粒被害率、损失率、抗性指数均有较大差异。其中表现高抗的品种(系)有4个,表现中抗的有18个,这些品种(系)可作为抗麦红吸浆虫的主栽和后备品种,或作为亲本材料提供给生产和育种利用。     

Screening for resistance to early blight (Alternaria solani) in potato (Solanum tuberosum L.) using toxic metabolites produced by the fungus

Summary The phytotoxic components of the culture filtrate of the fungusAlternaria solani Sor, which causes early blight in potato, were used in this study to differentiate between resistant and susceptible genotypes selected to represent a range of reactions when screened in the field. Detached leaflet assays, using spores and toxic metabolites from the culture filtrate, were compared with field ratings and a whole-plant glasshouse test. Rank correlations between several detached leaflet tests were highly significant (P<0.01) but the correlations between these tests and the glasshouse and field tests were poor. The disease ratings obtained in the various tests were clustered into four groups and assigned to resistance classes. For many of the genotypes there was a good correspondence between resistance classes for all test methods. Divergent results between tests were associated with foliage maturity characteristics of the genotypes. Contribution no. 3879050 of the Lethbridge Research Station.     

Potential use of Asteraceae extracts to control Spodoptera frugiperda (Lepidoptera: Noctuidae) and selectivity to their parasitoids Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) and Telenomus remus (Hymenoptera: Scelionidae)

Extracts of 12 Asteraceae were tested on Spodoptera frugiperda (Lepidoptera: Noctuidae) and on their parasitoids Telenomus remus (Hymenoptera: Scelionidae) and Trichogramma pretiosum (Hymenoptera: Trichogrammatidae). The plants Lychnophora ericoides and Trichogonia villosa were toxic for 97.7 ± 0.15% of one-day-old eggs of S. frugiperda and Lepidaploa lilacina for 72.0 ± 2.50% for two-day-old eggs of this insect. Extracts of Vernonia holosenicea, Lychnophora ramosissima and Chromolaena chaseae had higher impact on S. frugiperda, while those of Eremanthus elaeagnus and L. ericoides were more selective to T. pretiosum and T. remus. Asteraceae extracts present potential for integrated pest management programs of S. frugiperda.     

Cryotherapy of Potato Shoot Tips for Efficient Elimination of Potato Leafroll Virus (PLRV) and Potato Virus Y (PVY)

Viral diseases constitute a major constraint to high yield and high quality production of potato. Potato leafroll virus (PLRV) and Potato virus Y (PVY) are among the most damaging potato viruses and are prevalent in most potato growing areas. In the present study, attempts were made to eliminate PLRV and PVY by three cryogenic protocols, i.e., encapsulation-dehydration, encapsulation-vitrification and droplet. Results showed that both PLRV and PVY could be efficiently eliminated by cryogenic treatments with 83–86% and 91–95% of frequencies of virus-free plantlets obtained for the former and latter, respectively. Frequencies of virus-free plantlets produced by cryogenic treatments were higher than those by meristem culture (56% for PLRV and 62% for PVY) and thermotherapy (50% for PLRV and 65% for PVY), and similar to those by thermotherapy followed by meristem culture (90% for PLRV and 93% for PVY). Survival (75–85%) and regrowth (83–89%) from cryo-treated shoot tips were higher than those from meristem culture (50–55%) and thermotherapy followed by meristem culture (40–50%), but similar to those from thermotherapy (80–87%). The morphology of the plantlets regenerated from cryo-treated shoot tips was similar to that of non-treated plantlets. Thus, cryotherapy would provide an alternative method for efficient elimination of potato viruses, and can be simultaneously used for long-term storage of potato germplasm and for production of virus-free plants.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Elucidation of the sex pheromone system of the potato tuberworm moth,Phthorimaea operculella (Zeller) (Lepidoptera,Gelechiidae): a short review

Summary Recent research, reviewed here, of the pheromone system of the potato tuberworm moth has led to the isolation, identification, and synthesis of its components.trans-4,cis-7-tridecadien-l-ol acetate (PTM 1) andtrans-4,cis-7,cis-10-tridecatrien-l-ol acetate (PTM 2), mixtures of which are much more attractive in the field than 2 virgin female moths or each compound on its own.     

Fingerprinting Indian potato cultivars by random amplified polymorphic DNA (RAPD) markers

Summary Random amplified polymorphic DNA markers were used to distinguish and characterize 20 Indian potato cultivars. A total of 198 scorable fragments were amplified using 10 random primers, only two of which were monomorphic. Similarity values among the cultivars ranged from 0.33 to 0.80. A primer having resolving power above 7.4 was sufficient to distinguish all 20 cultivars. Wide variations in band profiles were observed when the same template DNA was amplified using Taq DNA polymerase from four different sources. No significant difference in profile complexity was observed at 40°C annealing temperature with a primer having 70% GC content. Prior restriction of template DNA resulted in band profiles whose complexity was similar to or higher than that of unrestricted template. However, multiplex RAPD with cleaved template DNA could not increase fingerprint complexity. Publication No. 1666, CPRI. Shimla     

A glasshouse progeny test for resistance to gangrene (Phoma foveata)

Summary Tubers were obtained from 80 glasshouse-grown seedlings of each of twelve progenies, inoculated withPhoma foveata Foister, and the mean percentage of infected tubers recorded. There was a good correlation (r=0.798) between this assessment and that made previously on field-grown tubers of eleven of the progenies. A gangrene test on glasshouse-grown tubers is suggested as a more rapid means of identifying progenies with useful levels of resistance.     

Modified crystal violet pectate medium (CVP) based on a new polypectate source (Slendid) for the detection and isolation of soft rot erwinias

Summary The selective-diagnostic crystal violet pectate (CVP) medium for the detection and isolation of soft rot erwinias was modified and improved to allow the use of a new source of sodium polypectate (Slendid type 440), as the previous polypectate (Bulmer) is no longer available. Two formulations were developed: CVP-S1 medium was less transparent but otherwise similar to the Bulmer polypectate-based CVP medium (CVP-B) except that NaOH was added and CaCl₂ concentration reduced. CVP-S2 medium was prepared by mixing equal volumes of two double strength preparations containing 1) polypectate and NaOH, and 2) all other ingredients, both sterilised separately. Although erwinia cavity formation was slower, it showed a number of advantages over CVP-B and CVP-S1 media, thereby facilitating colony/cavity detection and enumeration. These included the absence of precipitate, greater firmness and a reduced risk of liquefaction in the presence of large erwinia numbers, and a reduction in the number of saprophytic bacteria.     

Studies on life cycle of mealybug, Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae), on different hosts at different constant temperatures

The life cycle of a laboratory reared parthenogenic line of mealybug, Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae) was investigated on six host plants (Lagenaria siceraria var.clavata, Solanum tuberosum L. var. Kufri Chandramukhi, Praecitrullus fistulosus (Stocks) Pangalo var. MTNH1, Cucurbita pepo var. Styriaca, Triticum aestivum L. var. Lokvan, H. rosa sinensis L.) at five constant temperatures (25, 29, 35, 38, 42 °C). The number of emerging crawlers and adults as well as weight of adults varied with host and temperature. P. fistulosus and H. rosa sinensis were suitable hosts for laboratory rearing of M. hirsutus. However, ease of maintenance of P. fistulosus to produce M. hirsutus under laboratory conditions is an additional advantage compared to using green plants such as H. rosa sinensis. Among the range of constant temperatures, 38 °C was found to be the most favourable for the development and survival of M. hirsutus. These results suggest that P. fistulosus fruits are suitable hosts for laboratory rearing and life cycle studies of M. hirsutus.     

小麦β-酮脂酰CoA合成酶基因KCS的克隆与酵母表达

超长链脂肪酸是生物体内众多重要物质的合成底物。KCS基因编码β-酮脂酰CoA合成酶,该酶具有底物特异性,参与超长链脂肪酸延伸的缩合反应,是超长链脂肪酸合成的限速步骤。为了探究小麦KCS基因在超长链脂肪酸合成中的功能,采用同源克隆的方法从小麦(Triticum aestivum L.)中克隆出KCS基因后,利用生物信息学对其编码序列进行分析,并在酿酒酵母(Saccharomyces cerevisiae)中对其进行真核表达。结果表明,小麦TaKCS6基因的开放阅读框为1 287bp,编码428个氨基酸残基。结构域预测结果显示,TaKCS6蛋白含有III型聚酮合酶脂肪酸延伸酶和C末端3-酰基ACP合酶III结构域,属于KCSs蛋白家族。序列比对分析结果显示,TaKCS6氨基酸序列与拟南芥及其他植物的KCS6氨基酸序列在两个功能结构域上和活性位点保守。酵母表达结果显示,TaKCS6基因编码的蛋白参与C24以上超长链脂肪酸的延伸。