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1.
实践证明,棉农是国家实施棉花良种补贴的最大受益者,实现了棉花良种补贴的主要目的.有人对棉花良种补贴持有不同的态度,是因为棉农、种子企业和基层农技推广部门等相对独立的利益主体,均以从项目实施中获利多少来评价政策的优劣.棉种市场混乱是制约项目实施的关键因素,要提高项目实施水平,必须采取综合措施,重点是整治棉种市场,简化补贴操作程序.  相似文献   

2.
黑龙江省甜菜种植比较效益分析   总被引:3,自引:0,他引:3  
通过对相关数据的调查分析,详细比较了黑龙江省种植甜菜和玉米、大豆、马铃薯的成本、收入、收益情况。结果得出农户种植甜菜纯收益除了低于马铃薯外。明显高于其它作物。具有较高的经济效益。  相似文献   

3.
Rice line 1892S is an elite thermo-sensitive genic male sterile(TGMS)line for two-line hybrid rice production.However,1892S is susceptible to rice blast,bacterial blight and submergence.Here we reported the introduction of blast resistance(R)gene Pi9,bacterial blight R gene Xa21 and submergence tolerance gene Sub1A into 1892S genetic background through backcrossing and marker-assisted selection.The improved TGMS line 31892S and its hybrids conferred disease resistance to rice blast and bacterial blight,and showed submergence tolerance for over 14 d without significant loss of viability.The sterility-fertility conversion of 31892S was similar to that of 1892S.31892S and its derived hybrid rice had similar agronomic traits and grain quality with 1892S and the control hybrid rice,respectively.The newly developed 31892S provided an improved TGMS line for two-line hybrid rice production with disease resistance to rice blast and bacterial blight,and submergence tolerance with no yield penalty or change in grain quality.  相似文献   

4.
江苏省大丰市方强镇地处黄海之滨,植棉历史悠久,是典型的老棉区.棉花补充养分很重要,农民种棉花习惯在6月上中旬追施棉花苗肥,7月中旬追花铃肥,忽视了后期追肥.棉花追施盖顶肥是夺取高产的一项关键措施.种棉花想夺高产,必须抓住秋桃,秋桃盖顶非常重要,要抓住秋桃就必须追施盖顶肥,满足棉花后期生长需要.  相似文献   

5.
泡茶     
很久没有自己泡茶喝了,于是手就痒痒了起来,心也跟着痒痒。决定找个时间泡一下,这么想着想着,就心花怒放了,仿佛一个孩子即将要得到想要了很久的玩具,有些手舞足蹈。  相似文献   

6.
2009.9.22-2009.11.25在广州富国丽思卡尔顿酒店举行品牌活动。本次品牌评选活动由:中国国际品牌协会、中国新闻传播中心、中国轻工企业投资发展协会调研部联合主办根据2009中国茶品牌(乌龙、黑茶)金芽奖陆羽奖品牌评选方案,按照公开、公正、公平的评审原  相似文献   

7.
《茶世界》2008,(9)
太平猴魁简介:太平猴魁创制于1900年前后,是中国十大名茶之一,创制的时间虽不长,其茶树却是一个古老的原生品种一一柿大茶。柿大茶承云天之甘露,黄山之灵秀,加以传统的植茶之法及独特的制作工艺,便成太平猴魁。《南京市茶商业历史资料》中评论的徽茶分南北二路,南茶又名尖茶,以猴魁为最佳,全国名茶之极。其外形两叶抱一芽,俗称两刀一枪,平扁挺直,魁伟重实,有猴魁两头尖,不散不翘不卷边之称,色泽苍绿匀润,素有绿金王子的美誉,白毫隐伏,叶脉绿中隐红,俗称红丝线。  相似文献   

8.
中国工程院院士陈宗懋教授、美国哈佛大学麻省总医院研究员张群豪博士最近到漳州天福茶学院讲学访问,介绍最新科研成果,畅谈具有五千年悠久历史的中华国饮--茶叶之功效.……  相似文献   

9.
《福建茶叶》2009,31(2):57
古谚语:遂应场,两件宝,地下掘白银,山上采仙岩.说的就是锦屏村自宋朝开始便开采银矿,历时300余年.年税银多达5000两. "仙岩"则是指产于仙岩的茶叶,也就是著名的仙岩茶, 仙岩茶(俗称芽茶).……  相似文献   

10.
最近几年來本省夏秋茶產量有很大的增長,特别是1955和1956这兩年,可以看出夏秋茶產量在全年茶叶產量中的比重有顯著增大的趋势。由于夏秋茶產量的增加,对补救1955年初的冻害所造成的產量損失起了很大作用,1955年春茶比1954年減產达31159担,但夏秋茶不僅沒有減產,而且还比1954年增產3600多担;並且由于夏  相似文献   

11.
The morphological concept of Trichoderma koningii is found to include several species that differ from each other in details of phenotype (including conidium morphology, growth rate) and biogeography. Phylogenetic analysis utilizing partial sequences of the translation-elongation factor 1 alpha (tef1), as well as fragments of actin and calmodulin genes, indicate that phenotypic characters typical of T. koningii evolved independently in three well-separated main lineages. Combined molecular and phenotype data lead to the development of a taxonomy with the recognition of twelve taxonomic species and one variety within the three lineages. These lineages include: (1) T. koningii and T. ovalisporum and the new species T. caribbaeum var. caribbaeum, T. caribbaeum var. aequatoriale, T. dorotheae, T. dingleyae, T. intricatum, T. koningiopsis, T. petersenii and T. taiwanense; (2) the new species T. rogersonii and T. austrokoningii, and (3) the new anamorph T. stilbohypoxyli.Trichoderma koningii s. str. is an uncommon species restricted to Europe and eastern North America; T. caribbaeum var. aequatoriale, T. koningiopsis, and T. ovalisporum were isolated as endophytes of trunks of Theobroma species in tropical America, and T. ovalisporum from the woody liana Banisteropsis caapi in Ecuador; T. koningiopsis is common in tropical America but was isolated also from natural substrata in East Africa, Europe and Canada, and from ascospores in eastern North America, and as an endophyte in Theobroma species; T. stilbohypoxyli, originally described as a parasite of Stilbohypoxylon species in Puerto Rico, is found to be more common in the tropics, besides an endophytic isolate from Fagus in U.K. The additional new species are known almost exclusively from their teleomorphs. Isolates of T. ovalisporum and T. koningiopsis may have biological control potential. A morphophenetic key and a set of tools for molecular species identification were developed.Taxonomic novelties:Trichoderma austrokoningii/Hypocrea austrokoningii Samuels & Druzhinina sp.nov., T. caribbaeum var caribbaeum/H. caribbaea Samuels& Schroers sp.nov., T. caribbaeum var. aequatoriale Samuels & H.C. Evans var.nov., T. dingleyae/H. dingleyae Samuels & Dodd sp.nov., T. dorotheae/H. dorotheae Samuels & Dodd sp.nov., T. intricatum/H. intricata Samuels & Dodd sp.nov., T. koningiopsis/H. koningiopsis Samuels, C. Suarez& H.C. Evans sp.nov., T. petersenii/H. petersenii Samuels, Dodd & Schroers sp.nov., T. rogersonii/H. rogersonii Samuels sp.nov., T. stilbohypoxyli Samuels & Schroers sp.nov., T. taiwanense/H. taiwanensis Samuels & M.L. Wu sp.nov.  相似文献   

12.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

13.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

14.
为了促进贵州观光农业与生态环境的协调发展,本研究对传统绿肥贵州山地景观化利用潜力进行评价。以贵州主要种植的传统绿肥光叶苕子(Vicia villosa var.)、紫云英(Astragalus sinicus L.)、箭筈豌豆(Vicia sativa L.)、肥田萝卜(Raphanus sativus L.)、山黧豆(Lathyrus cicera L.)、油葵(Oil-sunflower)、二月兰[Orychophragmus violaceus (L.) O.E. Schulz]为研究对象,分析其花朵时空分布特征、花朵视觉特性等景观效益,以及各绿肥作物的生长特性及养分效益。二月兰的开花时间最早,随后是肥田萝卜、山黧豆、紫云英,接着是光叶苕子、箭筈豌豆,而油葵是夏季绿肥,初花期为6月中旬,花穗期17~43 d,花期长短表现依次为二月兰>肥田萝卜>油葵>光叶苕子>紫云英>山黧豆>箭筈豌豆。花朵分布高度为油葵150~200 cm、肥田萝卜75~95 cm、二月兰与光叶苕子及箭筈豌豆25~50 cm、紫云英和山黧豆15~25 cm。单株花朵数光叶苕子最多。单朵花面积油葵最大。单株花面积光叶苕子最大。结合观光与保育目标,可利用绿肥作物打造2—3月间的二月兰蓝紫色花海,3—4月间的紫云英紫红色花海、肥田萝卜白色花海,4月间的光叶苕子紫色花海,6—7月间的油葵黄色花海,以丰富贵州观光休闲农业的观光色调,延长观光时间,实现观光品牌的多样化。  相似文献   

15.
Résumé La capacité infectieuse de 5 espèces ou variétés deFusarium responsables de la pourriture des tubercules est étudiée.F. roseum var.sambucinum possède la capacité infectieuse la plus importante.F.r. var.arthrosporioides etF.r. var.culmorum sont, à l'inverse, caractérisés par une capacité infectieuse faible, ils ne produisent des pourritures qu'à des doses élevées de spores et sont rapidement limités par la cicatrisation. Enfin,F. solani var.coeruleum etF.r. var.graminearum possèdent un comportement intermédiaire. Le niveau de ‘virulence’ des 5Fusarium apprécié sur 9 cultivars, est identique mais leur niveau ‘d'agressivité’ varie; ils sont doués d'une agressivité non-spécifique (l'ensemble desFusarium provoque sur un cultivar déterminé, le même niveau de maladie) ou spécifique (une espèce ou variété deFusarium possède un comportement déterminé sur un cultivar qui ne correspond pas à celui des autresFusarium). Il est traité dans la discussion-conclusion de l'apport de ces résultats dans un programme de sélection vis-à-vis des Fusarioses.
Summary The objective of this study is to confirm the infective potential of 5 species or varieties ofFusarium causing dry rot in potato tubers (F. roseum var.sambucinum (F.r. samb.), F. solani var.coeruleum (F.s. coer.), F. roseum var.arthrosporioides (F.r. arth.), F. roseum var.culmorum (F.r. culm.) andF. roseum var.graminearum (F.r. gram.)) in relation to different factors: inoculum level, wound type, time taken for wound healing, physiological age of tubers and cultivar. At low inoculum levels, certainFusarium can be highly aggressive, for exampleF.r. samb. and to a lesser extentF.s. coer. andF.r. gram., whereas others (F.r. arth. andF.r. culm.) can initiate a rot only when the inoculum level is high (Fig. 1 and Table 1). With respect to wounding (Tables 2 and 3),F.r. samb. causes extensive lesions regardless of wound type in contrast to the otherFusarium which do so only when the wounds are deeper than 2 mm. The reaction of the differentFusarium to wound healing is variable (Fig. 2). Some(F.r. culm. andF.r. arth.) are usually not affected whereas with others infection is arrested after a longer healing time: 8 days in the case ofF.s. coer. andF.r. samb. and longer withF.r. gram. Wound healing reaction can modify the relative ranking order of cultivars; a cultivar classified as resistant to aFusarium in the absence of healing can find itself grouped with the less resistant ones after wound healing probably because of a rate of healing lower than that of the other cultivars (Table 4). Behaviour of the different species and varieties ofFusarium is not affected differently by the physiological age of tubers; disease level is lower in young than in older tubers (Table 5). Moreover, cultivar reaction is more pronounced on young than on older tubers.

Zusammenfassung Das Ziel dieser Studie ist es die Infektionskapazit?t von fünf Arten oder Sorten des für die Trockenf?ule der Kartoffelknollen verantwortlichenFusarium zu pr?zisieren (F. roseum var.sambucinum (F.r. samb.), F. solani var.coeruleum (F.s. coer.), F. roseum var.arthrosporioides (F.r. arth.), F. roseum var.culmorum (F.r. culm.) undF. roseum var.graminearum (F.r. gram.)) im Bezug auf diverse Faktoren: Inokulumdosis, Art der Verletzung, Wundheilungsdauer, physiologisches Alter der Knollen und Sorte. GewisseFusarium zeichen sich schon bei einer schwachen Dosis durch eine erh?hte Agressivit?t aus; dies ist der Fall fürF.r. samb. und mit verminderter St?rke, fürF.s. coer. undF.r. gram., die anderen hingegen (F.r. arth. undF.r. culm.) k?nnen nur bei gr?sseren Dosen von Impfstoff zu einer F?ule führen (Abb. 1 und Tab. 1). Was die Verletzungen betrifft (Tab. 2 und 3) provoziertF.r. samb. gr?sseren Schaden bei jeglicher Art von Verletzung im Gegensatz zu den anderenFusarium die nur bei einer Mindesttiefe der Verletzungen von 2 mm zu einer starken erkrankung fürhren. Im Bezug auf die Wundheilung sind unterschiedliche Reaktionen der verschiedenenFusarium zu beobachten (Darstellung 2); gewisse sind selten begrenzt (dies ist der Fall fürF.r. culm. undF.r. arth.), andere kommen nach einer l?ngeren Wundheilungszeit zum Stillstand: 8 Tage fürF.s. coer. undF.r. samb. oder noch l?nger fürF.r. gram. Die Vernarbungsreaktion kann das ungef?hre Sortenklassement ver?ndern; eine für ein Fusarium wenig empfindliche Sorte kann zu den Empfindlichsten geh?ren durch ihres Verhalten bei der Wundheilung, wenn ihre Vernarbungszeit l?nger dauert als die anderer Sorten (Tab. 4). Die verschiedenen Arten oder Sorten desFusarium reagieren auf gleiche Weise was das physiologische Alter der Knollen betrifft. Der Krankheitsbestand ist auf jüngeren Knollen schw?cher als auf ?lteren (Tab. 5). Weiter ist das Verhalten der verschiedenen Sorten deutlicher bei den jungen Knollen als bei alten.
  相似文献   

16.
Summary Recurrent backcrosses (BC) were used to introduce nuclear factors ofS. tuberosum L. ssp.tuberosum into the cytoplasm of Andean potatoesS. tuberosum ssp.andigena (Juz. and Buk.) Hawkes andS. phureja Juz. and Buk. Each generation BC was produced in reciprocal directions to test the effect of cytoplasmic substitution on yield. This report analyses tuber number, tuber weight, and tuber length of BC2 and BC3 substitution into ssp.andigena cytoplasm and BC2 and BC2 substitutions intoS. phureja cytoplasm. Direction of cross had no consistent significant effect on yield components of ssp.andigena substitution lines. InS. phureja reciprocal progenies direction of cross was responsible for significant differences of some reciprocal sets. When there were significant differences the higher yield usually occurred when ssp.tuberosum was the pistillate parent, but in some progenies when ssp.tuberosum was the pistillate parent the yield was significantly lower than in the reciprocals. It is suggested that differences between reciprocals resulted from chromosomally encoded gene action, resulting from maternal and/or paternal effects, rather than cytoplasmic factors. Authorized for publication as paper No. 7494 in the Journal Series of The Pennsylvania Agriculture Experiment Station.  相似文献   

17.
Zusammenfassung Es wurde versucht, die unterschiedlichen Ausbreitungsmechanismen der beiden Lagerf?uleerregerFusarium coeruleum undFusarium sulphureum physiologisch-biochemisch teilweise aufzukl?ren Alle Isolate vonF. coeruleum undF. sulphureum vermochten Pectinmethylesterasen (PME). Polygalacturonasen (PG), Cellulasen und Proteasen zu bilden. Die Synthese der PME erfolgte bei beiden Pilzen konstitutiv und wurde durch Substratzusatz erheblich gesteigert.F. coeruleum bildete auch PG konstitutiv, nicht jedochF. sulphureum. Die Cellulase-Synthese erfolgte bei beiden Pilzen konstitutiv, die der Protease bevorzugt konstitutiv. Die Kulturdauer beeinflusste die Syntheserate der Enzyme unterschiedlich. PME und PG vonF. coeruleum zeigten im Gegensatz zuF. sulphureum keinen Aktivit?tsabfall innerhalb von 39 Tagen. Die Cellulase-Synthese des ersteren Pilzes stieg bis zum 18. Tag an, um dann langsam abzufallen, die des letzteren fiel nach starker Aktivit?t bei 3 Tagen nach 6 Tagen stark ab, um dann aber wieder über den gesamten Zeitraum stetig anzusteigen. Anders verhielt sich die Protease-Synthese, die beiF. coeruleum mit ca. 21 Tagen ihr Optimum erreichte.
Summary In vivo,Fusarium coeruleum grows intercellularly andF. sulphureum intracellularly. The possible relationship between this and the activity of various enzymes has been investigated. All isolates ofF. coeruleum andF. sulphureum were able to produce pectinmethylesterases (PME), polygalacturonases (PG), cellulases and proteases. Both fungi synthesized PME constitutively, more being produced if substrate was added. PG was formed constitutively only byF. coeruleum. Cellulase synthesis was constitutive in both fungi and protease synthesis mainly constitutive (Fig. 2). The PME activity ofF. coeruleum was influenced by the N-source. inorganic N-compounds being more effective than organic in this respect. Peptone from casein was found suitable for PG activity. In contrast to the proteases, cellulase activity. In contrast to the proteases, cellulase activity was not greatly influenced by the N-source. The PME and PG ofF. coeruleum showed no loss of activity up to 39 days. The cellulase activity of this fungus increased up to 18 days and then declined. The cellulase activity ofF. sulphureum rose to a high level on the 3rd day. decreased after 6 days but increased again between the 9th and 39th day. Protease activity inF. coeruleum reached a maximum in 33 days and inF. sulphureum in 21 days (Table 2).

Résumé II a été essayé d'éclaircir en partie par la voice de procédés physiologico-biochimiques le mécanisme différent de la propagation durant la conservation des deux agents de pourritureFusarium coeruleum etFusarium sulphureum. Touslesisolats deF.coeruleum etF. sulphureum ont été capables de développer des pectines-méthylestérases (PME), polygalacturonases (PG), cellulases et protéases. Pour les deux champignons, la synthèse de PME a été réalisée de manière constitutive et sensiblement activée par l'adjonction de substrats.F. coeruleum élabore aussi le PG de manière constitutive, contrairement à F. sulphureum. La synthèse de la cellulase fut constitutive pour les deux champignons, celle de la protéase fut de préférence constitutive (fig. 2). Le taux de la synthèse des enzymes varie pendant la duréc de la culture. Contrairement àF. sulphureum, les PME et PG deF. coeruleum n'ont pas diminué leur activité durant 39 jours. La synthèse de la cellulase deF. coeruleum s'est accrue jusqu'au 18e jour pour régresser ensuite lentement, celle deF. sulphureum, après une intense activité durant les 3 premiers jours, a fortement diminué pendant 6 jours puis a augmenté de fa?on continue jusqu'à la fin de la période. La synthèse de la protéase a évolué différemment; pourF. coeruleum, elle a atteint son optimum après 21 jours environ (tableau 2).
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18.
Summary Morphological and biochemical parameters that could be involved in resistance to late blight were studied in non-infected and in infected potato hybrids resulting from a cross betweenSolanum phureja, resistant toPhytophthora infestans, and a susceptibleSolanum tuberosum. Some morphological differences between resistant and susceptible hybrids, indicating a positive correlation between stem diameter and phloem thickness in the stem and resistance toP. infestans, were observed. The lignin content in the leaves of the resistant hybrid rose upon infection byP. infestans. In the leaves of the susceptible hybrid, a diminution of the lignin content could be observed upon infection byP. infestans. In the same context, peroxidasic activity raised upon infection byP. infestans in both resistant and susceptible hybrids. Further characterization of the hybrid clones based on the polymorphism of peroxidases was attempted using isoelectric focusing.  相似文献   

19.
Summary Field-grown tubers of 22 progenies ofSolanum tuberosum L. generated in a crossing programme involving seven parents differing in resistance toFusarium coeruleum Lib. ex Sacc. andF. sulphureum Schlect. (=F. sambucinum Fuckel, teleomorphGibberella pulicaris (Fr.) Sacc.) were wound-inoculated with a cornmeal + sand culture of each pathogen. Parental genotypes were also included. The mean lesion size of each progeny was compared in 2 years of tests, as well as with published data on glasshouse-grown tubers. ForF. coeruleum there was a high correlation between years as well as with the glasshouse data, but no such correlations were apparent withG. pulicaris. Furthermore, parental and GCA values, as well as progeny means and mid-parent scores, also correlated highly forF. coeruleum but not forG. pulicaris. Glasshouse-grown tubers of 11 wildSolanum spp. were also inoculated with both pathogens. Some resistance to one or other, or both, was apparent, particularly inS. chacoense.  相似文献   

20.
The differences in morphological and chemical characteristics and pulpability of core and bark fiber of jute at different position, top, middle and bottom were studied. The fiber length at the middle part of both bark and core was longer than the top and bottom part. With increasing height from bottom to top lignin content is decreased and α-cellulose content increased. The bark had higher α-cellulose and lower lignin than core. The bark produced nitrobenzene oxidation products with larger syringaldehyde/vanillin (S/V) ratios than the core. The yields of nitrobenzene oxidation products in bark were higher than core. The analysis of neutral sugars suggested that xylose is the predominant sugar of hemicellulose in both bark and core. The bark had higher glucose and lower xylose as compared to core. Under identical conditions of pulping, bark gave higher pulp yield and lower kappa number than core. The bark pulp showed better bleachability than core pulp. The higher tensile index in core pulp and higher tear index in bark pulp were observed.  相似文献   

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