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1.
陇南地区小麦条锈病发生动态与治理 总被引：1，自引：0，他引：1
1985～1990年作者对甘肃省陇南地区小麦条锈病秋苗菌源动态、越冬情况及其春季流行等进行了调查研究。结果表明,该地区秋苗发病重、越冬菌源多是导致春季小麦条锈病大流行的重要原因之一。海拔1600～1800m及其相邻的部份地区秋苗发病严重或较重,是发病基地或菌源基地,亦是治理的关键地区。其治理的配套关键技术包,括改制控害、抗病品种合理布局、适期晚播和粉锈宁拌种等都是行之有效的技术。其中通过改制,建立新的农业生态体系,兼与抗病品种合理布局和调节播期相结合,构成综合的生态治理工程,并不断优化,便有可能实现持久控害致富的目的。 相似文献
2.
小麦条锈病抗病遗传及菌源基地基因布局研究进展 总被引：2，自引：0，他引：2
小麦条锈病是世界范围内严重影响小麦生产安全的重要病害。我国是世界上最大的小麦条锈病流行区,自成独立的流行体系。培育和种植抗病品种是防治病害最有效的措施。然而,小麦品种对条锈病的抗性常常由于病菌新小种的产生而丧失,这既是一个重大科学问题,也是一个亟待研究解决的生产实际问题。如何有效、合理地利用小麦的抗病性,植病学家和育种学家进行了一个多世纪的研究与探索,提出了各种理论与策略,开展了各种实践与探索。该文就小麦抗条锈病遗传及其基因布局研究进展进行综述,主要包括抗性鉴定评价、抗病基因发掘与利用、数量抗性位点定位、抗病基因克隆与功能解析、近等基因系创建与应用,以及抗源创制、抗病生态育种和大区基因布局等,并对深入开展抗条锈病基因发掘与利用和大区基因布局进行展望,以期为抗病育种和病害持续治理提供参考。 相似文献
3.
The severity of fusarium wilt is affected by inoculum density in soil, which is expected to decline during intervals when a non‐susceptible crop is grown. However, the anticipated benefits of crop rotation may not be realized if the pathogen can colonize and produce inoculum on a resistant cultivar or rotation crop. The present study documented colonization of roots of broccoli, cauliflower and spinach by Fusarium oxysporum f. sp. lactucae, the cause of fusarium wilt of lettuce. The frequency of infection was significantly lower on all three rotation crops than on a susceptible lettuce cultivar, and the pathogen was restricted to the cortex of roots of broccoli. However, F. oxysporum f. sp. lactucae was isolated from the root vascular stele of 7·4% of cauliflower plants and 50% of spinach plants that were sampled, indicating a greater potential for colonization and production of inoculum on these crops. The pathogen was also recovered from the root vascular stele of five fusarium wilt‐resistant lettuce cultivars. Thus, disease‐resistant plants may support growth of the pathogen and thereby contribute to an increase in soil inoculum density. Cultivars that were indistinguishable based on above‐ground symptoms, differed significantly in the extent to which they were colonized by F. oxysporum f. sp. lactucae. Less extensively colonized cultivars may prove to be superior sources of resistance to fusarium wilt for use in breeding programmes. 相似文献
4.
1979—1985年在四川省阿坝州越夏区进行条锈病发生规律调查。该地区海拔2900米以上的晚熟小麦约2.5万亩,条锈病持续发生至9月下旬,为自生麦苗和部分早播秋苗提供菌源。自生麦苗的发病面积近3万亩,其中休闲地约2.5万亩,主要分布在松潘、黑水2400—2900米地区,自生麦苗较多,发病较重;荞麦复种地约4000亩,主要分布在黑水、茂汶和汶川等地1700—2500米地带,自生麦苗较少,发病较轻。自生麦苗提供菌源的关键时期是9月上旬至10月下旬。秋苗发病面积约3.7万亩,主要分布在松潘、黑水2700—2950米地带,自9月中旬至12月下旬不断发生流行,而以8月中旬至9月中旬播种的秋苗发病较重,菌源较多,这在越夏菌源传播中起着很重要的作用。条锈菌在阿坝州又可越冬,构成周年侵染循环,常年流行,这不仅严重危害当地小麦生产,而且向广大冬麦区秋苗提供大量菌源。因此,综合治理阿坝州越夏区至关重要。 相似文献
5.
小麦持久抗性品种对中国条锈菌(系)抗病性特点的分析 总被引：15，自引：0，他引：15
小麦品种抗性谱鉴定、田间病情系统观察和抗性组分测定等结果表明,小麦持久抗条锈品种具显著的抗性特征,即成株期抗性谱很宽,有的品种甚至全生育期都表现抵抗,田间病情消长很慢且轻,成株期一般表现侵染机率低、病斑面积小、潜育期长。试验在控制条件下进行,便于操作,可用于小麦品种持久抗条锈性鉴定研究。 相似文献
6.
Resistance, epidemiology and sustainable management of Rhynchosporium secalis populations on barley 总被引：1，自引：0，他引：1
J. Zhan B. D. L. Fitt H. O. Pinnschmidt S. J. P. Oxley A. C. Newton 《Plant pathology》2008,57(1):1-14
Rhynchosporium secalis is one of the most destructive pathogens of barley worldwide, causing yield decreases of up to 40% and reduced grain quality. Rhynchosporium is a polycyclic disease. Primary inoculum includes conidia produced on crop debris, infected seeds and possibly ascospores, although these have not yet been identified. Secondary disease spread is primarily by splash dispersal of conidia produced on infected leaves, which may be symptomless early in the growing season. Host resistance to R. secalis is mediated by both 'major' or host-specific genes (complete resistance) and 'minor' genes of smaller, generally additive effects (partial resistance). Crop growth stage and plant or canopy architecture can modify the expression of resistance. Resistance genes are distributed unevenly across the barley genome, with most being clustered on the short arms of chromosomes 1H, 3H, 6H and 7H, or in the centromeric region or on the long arm of chromosome 3H. Strategies used to manage rhynchosporium epidemics include cultivar resistance and fungicides, and also cultural practices such as crop rotation, cultivar mixtures and manipulation of sowing date, sowing rate or fertiliser rate. However, the high genetic variability of R. secalis can result in rapid adaptation of pathogen populations to render some of these control strategies ineffective when they are used alone. Sustainable control of rhynchosporium needs to integrate major-gene-mediated resistance, partial resistance and other strategies such as customized fungicide programmes, species or cultivar rotation, resistance gene deployment, clean seed and cultivar mixtures. 相似文献
7.
Reem Aboukhaddour Thomas Fetch Brent D. McCallum Michael W. Harding Brian L. Beres Robert J. Graf 《Plant pathology》2020,69(3):418-432
Canada is one of the largest wheat producers in the world, and wheat is grown over an area spanning most of the southern latitudes, with the prairie region (provinces of Saskatchewan, Alberta, and Manitoba) being the main producer. Several pathogens and pests attack wheat, but at present fusarium head blight (FHB), stripe rust, and leaf spots are the most damaging diseases to wheat production in Canada. Historically, smuts, stem rust, and leaf rust caused major crop losses in Canada and can still pose serious threat if management practices are relaxed. Cropping practices used by Canadian farmers to grow and harvest wheat over the last century have influenced disease development and pathogen biology, affecting the severity, incidence, and prevalence of crop diseases over time. Changes such as reduced tillage coincide with emergence of residue-borne diseases, such as FHB and leaf spots, while the deployment of resistant cultivars and increased fungicide use has resulted in the reduction of common bunt, stem, and leaf rust. This review will discuss the influence of long-term cropping practices, alone or in combination, on the biology, emergence, and prevalence of wheat diseases in Canada over the last century. 相似文献
8.
Jennifer Anne Davidson Rohan B. E. Kimber 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(1):99-110
Ascochyta blight causes significant yield loss in pulse crops worldwide. Integrated disease management is essential to take
advantage of cultivars with partial resistance to this disease. The most effective practices, established by decades of research,
use a combination of disease-free seed, destruction or avoidance of inoculum sources, manipulation of sowing dates, seed and
foliar fungicides, and cultivars with improved resistance. An understanding of the pathosystems and the inter-relationship
between host, pathogen and the environment is essential to be able to make correct decisions for disease control without compromising
the agronomic or economic ideal. For individual pathosystems, some components of the integrated management principles may
need to be given greater consideration than others. For instance, destruction of infested residue may be incompatible with
no or minimum tillage practices, or rotation intervals may need to be extended in environments that slow the speed of residue
decomposition. For ascochyta-susceptible chickpeas the use of disease-free seed, or seed treatments, is crucial as seed-borne
infection is highly effective as primary inoculum and epidemics develop rapidly from foci in favourable conditions. Implemented
fungicide strategies differ according to cultivar resistance and the control efficacy of fungicides, and the effectiveness
of genetic resistance varies according to seasonal conditions. Studies are being undertaken to develop advanced decision support
tools to assist growers in making more informed decisions regarding fungicide and agronomic practices for disease control. 相似文献
9.
ABSTRACT Field-grown winter wheat was inoculated with a beta-glucuronidase-transformed isolate of Cephalosporium gramineum in two field seasons to elucidate the mode of infection in resistant and susceptible cultivars. Colonization of viable root epidermis and cortical cells occurred as soon as 15 days postinoculation and the pathogen was found in the vascular tissues by 20 days postinoculation, well before freezing soil temperatures occurred. Penetration occurred directly through the root epidermis and through wounds adjacent to emerging secondary roots. The pathogen also penetrated through root cap cells and colonized meristematic tissues near root tips to gain access to the vascular system. Lower stem base colonization was observed where the pathogen penetrated directly through the epidermis, wounds, or senescent tissues. Appressorium-like structures, which appeared to aid penetration of cell walls, were often found within cells of both roots and stems after initial colonization. The mechanisms of resistance were not apparent, but less colonization occurred in resistant than in susceptible cultivars. 相似文献
10.
Simulating evolution of glyphosate resistance in Lolium rigidum II: past, present and future glyphosate use in Australian cropping 总被引：1，自引：0，他引：1
Glyphosate is a key component of weed control strategies in Australia and worldwide. Despite widespread and frequent use, evolved resistance to glyphosate is rare. A herbicide resistance model, parameterized for Lolium rigidum has been used to perform a number of simulations to compare predicted rates of evolution of glyphosate resistance under past, present and projected future use strategies. In a 30‐year wheat, lupin, wheat, oilseed rape crop rotation with minimum tillage (100% shallow depth soil disturbance at sowing) and annual use of glyphosate pre‐sowing, L. rigidum control was sustainable with no predicted glyphosate resistance. When the crop establishment system was changed to annual no‐tillage (15% soil disturbance at sowing), glyphosate resistance was predicted in 90% of populations, with resistance becoming apparent after between 10 and 18 years when sowing was delayed. Resistance was predicted in 20% of populations after 25–30 years with early sowing. Risks of glyphosate resistance could be reduced by rotating between no‐tillage and minimum‐tillage establishment systems, or by rotating between glyphosate and paraquat for pre‐sowing weed control. The double knockdown strategy (sequential full rate applications of glyphosate and paraquat) reduced risks of glyphosate and paraquat resistance to <2%. Introduction of glyphosate‐resistant oilseed rape significantly increased predicted risks of glyphosate resistance in no‐tillage systems even when the double knockdown was practised. These increased risks could be offset by high crop sowing rates and weed seed collection at harvest. When no selective herbicides were available in wheat crops, the introduction of glyphosate‐resistant oilseed rape necessitated a return to a minimum‐tillage crop establishment system. 相似文献
11.
R. B. E. Kimber E. S. Scott M. D. Ramsey 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(2):175-184
Ascochyta blight of chickpea (Cicer arietinum), caused by the fungus Didymella rabiei, has the potential to cause 100% crop loss in severe epiphytotics. Management of this disease often involves reducing sources
of inoculum. The influence of sowing depth, host resistance, seed infection level and soil temperature on disease transmission
was investigated in a series of glasshouse and growth room trials using seed artificially inoculated with D. rabiei. A positive correlation (R2=0.9992) was observed between rate of seed infection and the incidence of disease on seedlings. Disease transmission to seedlings
was not significantly influenced by sowing depth (1, 3 and 6 cm) in separate trials on two cultivars. Susceptibility of the
host showed no obvious influence on the frequency of disease transmission in two trials conducted using four cultivars ranging
from highly susceptible to moderately susceptible/moderately resistant. Trials conducted in controlled conditions showed that
there was no obvious relationship between soil temperature (5, 9, 14 and 19 °C) and the incidence of disease on seedlings. 相似文献
12.
Cereal cyst nematode is a major pathogen in southern Australia costing $40 to $80 million in lost production each year. Our research has shown that three chemicals applied with the seed in the drill row, viz. Counter (terbufos) granules, Vydate (oxamyl) as a seed dressing and Nemadi (ethylene dibromide), reduced Heterodera avenae damage and gave yield increases which are economical in the Australian wheat farming system. A plant assay of soil has been developed to assess potential damage by H. avenae before employing chemical control. Wheat yields 2 years after growing H. avenae-resistant Festiguay wheat were 0.4 to 1 t/ha higher than after other cultivars. Rotations with legumes alternating with wheat reduced damage from H. avenae. Wheat sown without cultivation (minimum tillage) resulted in less root damage from H. avenae and higher yields than when sown into cultivated soil. 相似文献
13.
四川省不仅是条锈菌冬繁区,也是我国东部麦区重要的春季初侵染菌源地和毒性变异地。准确评价四川小麦新育成品种和高代品系对条锈病的抗性水平,能为合理培育和使用抗病品种提供重要依据。利用当前条锈菌优势小种和4个地点的成株期鉴定圃对来自四川省的115份小麦育成品种和299份高代品系进行苗期和成株期抗病性鉴定。结果表明,新育成品种苗期对优势小种的高抗CYR32、CYR33和CYR34的比例发生不同程度的变化,对CYR32的高抗比例为40.9%、对CYR34的高抗比例为17.4%,而供试高代品系高抗比例从52.3%降至46.2%;中抗类型育成品种从20.0%增加到40.9%,高代品系从19.6%增加至33.2%。表明条锈菌优势小种更替后一些材料仍保留了部分抗性,后期选育的高代品系兼顾对新小种的抗病性。育成品种在四川成都和甘肃清水成株期鉴定,高抗品种所占比例较低,分别为13.9%和3.5%,但高代品系高抗类型比例较高,分别为42.2%和8.5%,表明甘肃和四川条锈菌的致病类型和发病环境条件存在较大差异,近年来四川小麦成株抗条锈病育种取得显著进展。 相似文献
14.
78个重要小麦品种苗期抗条锈性的聚类分析 总被引：3，自引：1，他引：3
选用20个具有不同毒性谱的条锈菌菌系,对78个重要小麦品种材料进行了苗期接种鉴定,以得到的数据为基础,用类平均法对供试小麦品种的抗条锈性进行了聚类分析。鄂恩1号等19个品种被聚在一类,它们具有Yr9或与之相似的抗性;碧玛1号等10个品种被聚在一类,它们具有Yr1或与之相似的抗性;兰天5号等9个品种聚为一类,它们可抗所有供试菌系或仅对1～2个菌系感病;还有些品种被分别聚合为几小类。获知了一批具有未知抗条锈基因或基因组合的重要小麦品种的抗性特点,本结果可为小麦生产品种的合理布局与利用、抗锈育种中抗源的选用以及生产品种抗性变异预测提供重要依据。 相似文献
15.
ABSTRACT Cephalosporium stripe is an important disease of winter wheat (Triticum aestivum) in several areas of the world, especially where stubble mulch and early seeding are practiced to maintain soil moisture and prevent erosion. We developed a procedure to mass-produce a toxic fraction produced by Cephalosporium gramineum through a modification of the method of Kobayashi and Ui. Exposure of excised wheat leaves to a concentration of 60 mul/ml of the toxic fraction for 72 h produced distinct wilting symptoms that allowed us to distinguish toxin-sensitive wheat genotypes in a repeatable manner. Twenty wheat genotypes belonging to four distinct germ plasm groups (common, club, durum, and synthetic) were evaluated. Variation in toxin sensitivity of wheat genotypes was mostly at the level of the germ plasm group, and all differences among the four germ plasm groups were highly significant (P < 0.001) based on linear contrasts. Seventeen winter wheat genotypes representing the common, club, and durum germ plasm groups were planted in C. gramineum-infested fields at two locations. The logarithm of the percentage of tillers showing whitehead symptoms at each of the two locations was significantly (P < 0.0001) correlated with wilting symptoms measured by the toxin assay (r = 0.80 and 0.84). The common wheat genotypes were all sensitive to the toxic fraction, but showed a substantial range of disease reactions in the field. However, we found no case of a toxin-insensitive genotype being susceptible in the field. These results suggest that toxin insensitivity may be an important mechanism of resistance to Cephalosporium stripe, but that other mechanisms are operative as well. The toxin assay may be useful as an initial screening procedure to reduce the number of genotypes to be tested in the field. 相似文献
16.
ABSTRACT Most barley cultivars are resistant to stripe rust of wheat that is caused by Puccinia striiformis f. sp. tritici. The barley cv. Steptoe is susceptible to all identified races of P. striiformis f. sp. hordei (PSH), the barley stripe rust pathogen, but is resistant to most P. striiformis f. sp. tritici races. To determine inheritance of the Steptoe resistance to P. striiformis f. sp. tritici, a cross was made between Steptoe and Russell, a barley cultivar susceptible to some P. striiformis f. sp. tritici races and all tested P. striiformis f. sp. hordei races. Seedlings of parents and F(1), BC(1), F(2), and F(3) progeny from the barley cross were tested with P. striiformis f. sp. tritici races PST-41 and PST-45 under controlled greenhouse conditions. Genetic analyses of infection type data showed that Steptoe had one dominant gene and one recessive gene (provisionally designated as RpstS1 and rpstS2, respectively) for resistance to races PST-41 and PST-45. Genomic DNA was extracted from the parents and 150 F(2) plants that were tested for rust reaction and grown for seed of F(3) lines. The infection type data and polymorphic markers identified using the resistance gene analog polymorphism (RGAP) technique were analyzed with the Mapmaker computer program to map the resistance genes. The dominant resistance gene in Steptoe for resistance to P. striiformis f. sp. tritici races was mapped on barley chromosome 4H using a linked microsatellite marker, HVM68. A linkage group for the dominant gene was constructed with 12 RGAP markers and the microsatellite marker. The results show that resistance in barley to the wheat stripe rust pathogen is qualitatively inherited. These genes might provide useful resistance against wheat stripe rust when introgressed into wheat from barley. 相似文献
17.
18.
This study reviews 52 field experiments, mostly from the UK, studying the effects of cultivation techniques, sowing date, crop density and cultivar choice on Alopecurus myosuroides infestations in cereal crops. Where possible, a statistical meta‐analysis has been used to calculate average responses to the various cultural practices and to estimate their variability. In 25 experiments, mouldboard ploughing prior to sowing winter cereals reduced A. myosuroides populations by an average of 69%, compared with non‐inversion tillage. Delaying drilling from September to the end of October decreased weed plant densities by approximately 50%. Sowing wheat in spring achieved an 88% reduction in A. myosuroides plant densities compared with autumn sowing. Increasing winter wheat crop density above 100 plants m?2 had no effect on weed plant numbers, but reduced the number of heads m?2 by 15% for every additional increase in 100 crop plants, up to the highest density tested (350 wheat plants m?2). Choosing more competitive cultivars could decrease A. myosuroides heads m?2 by 22%. With all cultural practices, outcomes were highly variable and effects inconsistent. Farmers are more likely to adopt cultural measures and so reduce their reliance on herbicides, if there were better predictions of likely outcomes at the individual field level. 相似文献
19.
陇南小麦条锈病的品种遗传多样性控制 总被引：7，自引：1，他引：6
为实现陇南小麦条锈病持续控制的目标,以遗传多样性为原则,组建以提高生产品种抗条锈基因丰富度、在锈菌越夏区和越冬区进行基因布局和持久抗性、慢条锈性、高温成株抗性等多种抗性利用为主要内容的控制技术体系。利用Yr10、Yr12、Yr13、Yr16、Yr26、YrC591等有效抗条锈基因的载体品种、Flinor 等持久抗性品种及中四等其它抗源材料育成一批综合性状优良、具有不同遗传背景的抗病品种和类型,其中2004年以来育成的10个品种产量性状有明显提高,在区域试验中较对照增产7.3%~28.9%。陇南小麦条锈病的控制已进入一个新阶段。 相似文献
20.
为挖掘新的小麦抗条锈病基因,掌握小麦生产主栽品种的抗条锈病基因携带情况,有效防控小麦条锈病,采用抗性鉴定、基因推导分析和分子标记技术对22份小麦生产上主栽品种进行了研究,通过抗性鉴定比较22份小麦主栽品种与已知基因载体品种的抗谱。结果显示,共推测出14份供试品种携带已知抗条锈基因,8份供试品种携带未知抗条锈基因,是新的抗锈基因资源;聚类分析结果显示,供试22份小麦品种可分为2个大类6个亚类;利用SSR分子标记检测抗条锈病基因Yr1、Yr10和Yr24的携带情况发现,11份品种携带Yr1基因,2份品种携带Yr10基因,22份品种均不携带Yr24基因。部分生产主栽品种携带新的抗条锈病基因,表明小麦品种选育中避免了抗性基因单一化,并加强了未知基因的利用。 相似文献