北方地区部分酿酒葡萄品种短须螨田间调查

2007年春季,对20个酿酒葡萄品种(系)短须螨发生情况进行了田间调查。调查结果显示,不同品种(系)受害程度差异明显。其中梅鹿辄181受害最重(虫叶率98%,8.5头/片),西拉次之,霞多丽、紫大夫、马瑟蓝、小味儿多和爱娇多拉受害轻,虫叶率<10%,平均虫口数<0.15头/片。     

葡萄感染霜霉病菌后几种信号物质的变化

以3个抗病性不同的酿酒葡萄品种(‘西拉’‘霞多丽’‘赤霞珠’)叶片为材料,检测霜霉病菌侵染后几种病原相关信号物质,如脱落酸(ABA)、过氧化氢(H2O2)、一氧化氮(NO)、茉莉酸(JA)和乙烯(ETH)等的变化,以探讨葡萄抵御霜霉病菌的信号转导机制。结果表明,H2O2和NO是葡萄感应霜霉病菌的早期信号分子,且抗性较强的品种‘西拉’的变化最为明显;JA和ABA是抗性较差品种‘赤霞珠’应答霜霉病的信号组分。而3个抗性不同葡萄品种的乙烯变化无明显差别。推测H2O2、NO、JA和ABA均参与了葡萄对霜霉病菌的防御反应,但不同品种间信号转导组分可能存在差异。     

山东葡萄产区主要病毒病发生危害调查

采用DAS- ELISA检测方法 ,对山东省葡萄主产区的葡萄病毒病害进行了调查 ,明确危害当地葡萄主要是葡萄扇叶病毒 (grapevine fanleaf virus ,GFLV)和葡萄卷叶病毒 (grapevine leafroll associated virus,GLRaV)。病毒感染率为 59.1% ,其中鲜食品种病毒感染率为57% ,酿酒品种的感染率为 62.5%。苗木与成龄树感染GFLV的比率分别为 78.4%和56% ,感染GLRaV的比率分别为55.3%和70%。病毒感染率较高的品种有霞多丽、梅露汁和佳丽酿。病毒病的发生与品种、栽培年限、繁殖方式和苗木来源有关 ,其中带毒苗木是葡萄病毒病传播的关键因素     

大白菜品种对孤丁病的抵抗性及其选育方法的基础研究初报

1960年进行的广泛调查及试验,肯定了应用抗病品种是防治白菜三大病害(孤丁、霜霉、软腐)的基础。虽然尚未发现有对孤丁和霜霉病的免疫品种,但品种间的抗病性差异极其显著,各地均有一部分适应本地种植的抗病性较强的品种可资应用,为了进一步解决品质等园艺性状和抗病性之间的矛盾,杂交育种的方法已开始研究。     

54个小麦品种(系)抗赤霉病评价与农艺性状调查

为获得抗赤霉病且农艺性状较好的小麦种质资源, 加快小麦抗赤霉病育种进程, 采用人工接种鉴定和田间试验的方法, 于2019年-2021年, 对54个小麦品种(系)进行了赤霉病抗性鉴定与农艺性状调查。结果表明, 供试小麦品种(系)存在赤霉病抗性差异, 筛选出‘华皖麦24’‘宛1204’和‘皖垦麦1708’等9个两年表现稳定的中抗品种(系), 占总数的16.67%; 农艺性状调查结果显示, 不同小麦品种(系)的农艺性状间存在显著性差异, 抗病组品种(系)的平均变异系数小于感病组品种(系)。其中, ‘宛1204’和‘徐麦17252’中抗赤霉病, 且综合农艺性状较好, 可以作为抗赤霉病育种的抗源。     

小麦品种(系)对叶枯病的抗病性鉴定研究

1989-1991年连续两年对62个小麦品种(系)进行抗叶枯病鉴定,供试各品种(系)间抗病性有明显差异,但无免疫类型,且中抗、中感类型较多,抗病类型较少;综合评定结果表明,尉氏132、鲁215953、郑州83203等5个品种(系)为抗病类型,占8.07％;豫麦2号、陕农7859、西安8号等31个品种(系)为中抗类型,占50％;豫麦17号、冀麦5418等21个品种(系)为中感类型,占33.87％;感病和高感类型,占8.6％。在研究品种(系)抗性与生物学特性的关系中,发现品种(系)抗性与植株形态,如株高、单茎叶面积等有一定相关性。     

黄瓜苗期对菌核病抗性筛选研究

采用离体叶片菌丝体接种法和活体叶片菌丝体接种法对19 份黄瓜品种( 系) 进行了黄瓜菌核病抗性筛选。结果表明:黄瓜品种C1 、A15 、甘丰2 号、中农2 号的抗病性较强。中农7 号、828 等品种具一定的抗病性。其余品种( 系) 大多抗病性较差,其中津春3 号、山东密刺较感病。     

生姜品种资源对姜瘟病的抗病性鉴定

为明确引自国内外的不同生姜品种对姜瘟病的抗病性,于人工病圃内采用人工接种方法测定了58个生姜品种对姜瘟病的抗病性,并在无姜瘟病发生的试验田内,对各品种的农艺性状进行了测定。结果表明,供试生姜不同品种的抗病性差异明显,现有生姜品种多为高感、感病品种,其中,安徽阜阳大姜、四川犍为黄口姜、厦门同安土姜等3个品种表现为中抗,7个品种表现为轻抗,9个品种表现为感病,39个品种表现为高感。主要农艺性状测定结果表明,3个中抗品种的产量性状表现突出,是姜瘟病重发区推广应用的首选品种。     

攀西地区酿酒葡萄破眠剂处理提高抽枝率研究

2003~2004和2004~2005年两个冬季,在四川省攀西地区对霞多丽、佳美、梅鹿辄、黑虎香四个葡萄品种休眠冬芽进行了化学药剂处理。翌年抽枝率结果表明:在冬季气温最低时处理四个品种的抽枝率均有提高;1.0%H2CN2 1.0%吐温80处理抽枝率提高最大;葡萄品种成熟期不同,对化学药剂处理的反应亦不相同,品种按处理与对照的萌芽率比值大小排序,依次为早中熟品种佳美、中熟品种梅鹿辄、早熟品种霞多丽、晚熟品种黑虎香。     

我国部分水稻品种对稻瘟病的抗谱测定

选用10省6群16个稻瘟病菌生理小种,对10省29个研究所提供的318个水稻品种(系)进行测定,提出加农Si-Pi661020、81005等19个抗性品种(系)可作杂交亲本利用,对其中经济性状较好的品种(系)可根据各省当地小种的出现频率和分布情况,在较大范围内种植。 本试验选用我国近年分离的16个稻瘟菌生理小种,对318个有希望的水稻品种(系)进行了苗期抗稻瘟病谱测定和田间人工接种、自然诱发3病(稻瘟病、白叶枯病、纹枯病)的鉴定,为全面评价供测品种(系)的抗病性提供依据^[2]。现将试验的方法和结果简述如下:     

Clonality and long-distance migration of Puccinia striiformis f.sp. tritici in north-west Europe

The biotrophic fungus Puccinia striiformis f.sp. tritici , a basidiomycete that causes yellow rust on wheat, is spread by wind-dispersed spores. Analysis of amplified fragment length polymorphism (AFLP) variation showed that the fungus frequently migrates between the UK, Germany, France and Denmark. There is no biological evidence for sexual or parasexual reproduction under natural conditions, and this was supported by the lack of recombination, as revealed by AFLP, over the time and area represented by the samples in this study. A phylogeographic analysis revealed that there was effectively a single, clonal population in the four countries, up to 1700 km apart, consistent with a 'continent-island' model in which Denmark is the recipient of migrants from other countries. In five cases, specific pathogen clones were dispersed between the UK and Denmark, and on at least two recent occasions clones were also spread from the UK to Germany and France, causing outbreaks of yellow rust on wheat cultivars that were previously resistant to the disease in these countries. The agronomic consequences of migration were enhanced because of the limited genetic diversity for yellow rust resistance in wheat cultivars in the area. These results demonstrate that long-distance migration of pathogen clones, coupled with low diversity in the host species, may cause previously useful resistance genes to become ineffective for disease control on a continental scale.     

Breeding Cassava for Resistance to Bacterial Blight

Abstract

It is noted that cassava bacterial blight (CBB) has been reported in several African countries and that heavy infection with CBB can lead to total crop failure as most local varieties are very susceptible. The best control method is through varietal resistance. IITA has made progress in breeding for resistance to both CBB and cassava mosaic disease (CMD) incorporating simultaneously other desirable agronomic qualities. The cassava breeding work at IITA since 1972 is then discussed covering tests on a total of 583 cassava families from CIAT, East Africa and IITA for sources of high resistance to CBB, further tests on 748 IITA clones for CBB resistance in a given ecological setting of high rainfall, sandy and acid soil from which the cultivar 58308 emerged highly resistant. Other aspects of the breeding work treated are conditions affecting varietal selection, namely: genetic mechanism resistance: stability of resistance to CBB over time and in different areas in Africa; high heritability; genetic correlation between resistance to CBB and CMD; correlation of CBB resistance with other characteristics such as tuber yield and leaf defoliation; and finally some factors affecting CBB field scores which are time of planting, age of plant and time of observation.

It is noted that the sources of high resistance to CBB identified have been quickly and successfully incorporated into promising cassava clones.     

Grapevine virus A variants of group II associated with Shiraz disease in South Africa are present in plants affected by Australian Shiraz disease,and have also been detected in the USA

Primers were designed for RT‐nested PCR amplification of the highly variable 293‐nt fragment from the 5′ terminal part of the Grapevine virus A (GVA) replicase gene, specific to South African variants of molecular groups I and II. This new technique, along with RT‐PCR for simultaneous amplification of variants of groups I, II and III, as well as cloning of amplicons, single‐strand conformation polymorphism (SSCP) analysis of clones and sequencing, were used to investigate the populations of variants infecting 16 local Shiraz grapevines with different Shiraz disease (SD) status. The techniques were also used to study variants in GVA‐infected grapevines from Australia and the USA. The Australian grapevines included seven plants of cvs Shiraz and Merlot affected by Australian Shiraz disease (AuSD), and one plant of cv. Crimson Seedless with unknown AuSD status. Grapevines from the USA included plants of cvs Chardonnay, Thompson Seedless and an unknown cultivar. The results confirmed the association of certain genetic variants of group II with SD and showed the common presence of these variants in AuSD‐affected grapevines from Australia. Interestingly, a variant of this group was also detected in grapevine cv. Chardonnay from the USA, although the disease has not yet been reported from that country. The study also supports an earlier observation that members of group II, closely related to variant GTR1‐2, are not associated with the disease. The variants were found only in SD‐free grapevines. Results show that variants of the most divergent group III, which are common in South Africa, are also present in Australia and the USA. These variants are not associated with SD, but frequently occur in mixed infections with members of group II in plants affected by this disease in South Africa.     

A model system for rapid selection for resistance and investigation of resistance mechanisms in Fusarium wilt of oil palm

Fusarium wilt ( Fusarium oxysporum f.sp elaeidis ) is the most serious disease of oil palm in Africa. Control measures are dependent upon breeding for resistance, but the lack of a rapid screen for resistance and lack of understanding of the underlying resistance mechanisms has constrained breeding programmes. A novel petiole infusion technique is reported that exploits the ability of the majority of petiole cells to express disease resistance or susceptibility. A clear correlation was found between disease resistance or susceptibility of six clones and external symptoms and fungal colonization in petioles. Antifungal compounds accumulated in resistant but not in susceptible clones in response to inoculation; there was also some evidence of preformed antifungal compounds in resistant clones. Further investigation of resistance mechanisms can be undertaken using this model system. The use of this novel technique, both as a potential rapid replacement for current nursery selection methods (time reduced from 8 months to 8 days) and as an assessment of resistance in individual field palms, is discussed. *     

Culex pipiens pallens: identification of genes differentially expressed in deltamethrin-resistant and -susceptible strains

Insecticide-resistance is a major obstacle to controlling insect vectors of microorganisms that cause human diseases. Identification of genes associated with resistance to insecticides has been a valuable tool for understanding mechanisms underlying resistance to commonly used insecticides such as deltamethrin. To identify such genes, we used suppression subtractive hybridization to obtain 809 differentially expressed clones in deltamethrin resistant versus susceptible laboratory strains of Culex pipiens pallens. Using cDNA microarrays and reverse Northern blots, a subset of 16 clones was confirmed to have greater than 3-fold difference in expression levels. Within this subset, we identified 2 clones uniquely expressed in the deltamethrin-resistant strain, eight clones exhibiting higher expression in the resistant strain and six in the susceptible strain. Of these 16 clones, 13 clones have sequence homology to known genes, such as ribosomal RNA, ribosome proteins, trypsin, and chymotrypsin-like proteins. Our data suggests resistance to deltamethrin may be a polygenic phenotype.     

Influence of host resistance and phenology on South American leaf blight of the rubber tree with special consideration of temporal dynamics

South American leaf blight (SALB), the most dangerous disease of the rubber tree, is responsible for the lack of significant natural rubber production in South America and is a major threat to rubber tree plantations in Asia and Africa. Although the selection of resistant clones is the preferred disease control method, greater knowledge is required of the relationship between host and pathogen, in order to construct more durable resistance. Based on small-scale trials, this study set out to compare the dynamics of SALB on two highly susceptible and one moderately susceptible clone and to analyse the effect of host phenology on disease severity, at leaflet and flush scales. Clonal resistance was found to have a noticeable effect on disease severity, asexual sporulation and stromatal density at both leaflet and flush levels, and on disease dynamics at a leaflet level; time for symptom and sporulation appearance were longer on the moderately susceptible clone than on the susceptible clones. On the moderately susceptible clone, the stromatal density was largely dependent on disease severity. The phenology did not differ among the three clones and could not be considered as a factor in genetic resistance to SALB. However, for the three clones, the position of the leaflet in the flush affected the duration of the immature stages and the disease: the shorter the duration of leaflet development, the lower the disease severity, the sporulation intensity and the stromatal density.     

我国新育成甘蔗品种(系)对甘蔗线条花叶病毒和高粱花叶病毒的抗性评价

甘蔗花叶病是中国蔗区危害最严重的病毒病,利用抗病品种是控制该病害最经济有效的方法。本研究以中国蔗区甘蔗花叶病的2种主要病原甘蔗线条花叶病毒分离物(SCSMV-JP1,Gen Bank登录号JF488064)和高粱花叶病毒分离物(Sr MV-HH,Gen Bank登录号DQ530434)为接种毒源,采用人工切茎接种和RT-PCR检测相结合方法,于2015年、2016年2次对中国近年选育的71个优良甘蔗新品种(系)进行了双抗SCSMV和Sr MV鉴定与评价。结果表明:71个优良甘蔗新品种(系)中,对SCSMV表现高抗到中抗的有24个,占33.8%,感病到高感的有47个,占66.2%;对Sr MV表现高抗到中抗的有27个,占38.03%,感病到高感的有44个,占61.97%。综合分析结果显示,福农30号、福农36号、闽糖01-77、桂糖02-467、柳城05-129、粤甘34号、粤甘40号、粤糖55号、粤糖96-86、粤糖00-318、赣蔗02-70、云蔗03-258、云蔗04-241、云蔗05-51、云蔗06-80等15个优良新品种(系)双抗SCSM V和Sr M V 2种病毒,占21.13%,其中粤甘34号、粤糖55号、云蔗03-258、云蔗05-51、云蔗06-80等5个优良新品种(系)对2种病毒均表现为高抗,占7.04%,。研究结果明确了71个甘蔗优良新品种(系)对甘蔗花叶病2种主要致病病原的抗性,筛选出双抗SCSMV和Sr MV的甘蔗优良新品种(系)15个,为生产用种选择和有效防控甘蔗花叶病提供了科学依据。     

Induced expression of sucrose synthase and alcohol dehydrogenase I genes in phytoplasma-infected grapevine plants grown in the field

Interaction between phytoplasma and grapevine at the physiological level is still poorly understood, as are plant defence mechanisms against the pathogen. This study investigates the level of gene expression of three selected genes in a large number of grapevine plants belonging to six disease/cultivar groups (healthy Chardonnay, Bois noir-infected Chardonnay, Flavescence dorée-infected Barbera and Prosecco, and recovered Barbera and Prosecco). All plants were grown in vineyards in uncontrolled conditions in order to represent the physiology of disease as accurately as possible. Sucrose synthase was significantly upregulated in infected plants of all cultivars with the lowest P -values in cvs Chardonnay and Prosecco ( P  < 0·001) and median fold-change around 2. This clearly indicates that carbohydrate metabolism changed in infected compared to healthy or recovered plants. Alcohol dehydrogenase I was significantly upregulated in infected relative to healthy Chardonnay plants ( P  < 0·05) indicating that alcoholic fermentation, a sign of hypoxic conditions, was induced in infected plants. Heat shock protein 70 was upregulated in infected compared to recovered plants only in cv. Prosecco. Linear discriminant analysis showed that classification of samples into disease status groups based on gene expression was highly accurate (82%), indicating that the response of field-grown plants to phytoplasma infection at the level of expression of selected genes was so intensive and uniform that it was possible to detect it in grapevine plants regardless of natural variables.