Management Of Rust Disease Research Articles

Identification of hub genes associated with stripe rust disease in wheat through integrative transcriptome and gene-based association study

Stripe rust poses a severe menace to wheat cultivation worldwide, occurring as the most devastating disease threatening global wheat industry. The use of resistance genes has been considered as an effective method for management of rust diseases. However, for most of yellow rust (Yr) genes, the molecular mechanisms and pathways responsible for resistance response against Puccinia striiformis (Pst) infection are not well understood. In this study, transcriptome analysis was conducted in two cultivars viz. PBW343 (susceptible) and FLW30 (resistant) to the pathotype 46S119 of Pst in India. The inoculation with Pst pathotype 46S119 was followed by leaf sample collection at different hours per inoculation (hpi) viz.12, 48, and 72. The transcriptome analysis revealed a total of 18,482 differentially expressed genes (DEGs) across different time points. However, a set of 159 genes were identified to exhibit a genome-wide association with P ≤ 0.05 level of significance, which can be represented as Nominally Significant GWAS Geneset (NSGG). By utilizing Weighted Gene Co-expression Network Analysis (WGCNA), we identified 924 and 79 genes from the DEGs and NSGG dataset belonging to different modules. Functional validation of genes was done to confirm the transcriptional expression of four potential genes, including two hub genes associated with the defence mechanism against rust infection.

Advancing Coffee Leaf Rust Disease Management: A Deep Learning Approach for Accurate Detection and Classification Using Convolutional Neural Networks

Coffee Leaf Rust (CLR), caused by the fungus Hemileia vastatrix, poses a severe threat to global coffee production. Timely detection is critical for effective control measures. This study employs Convolutional Neural Networks (CNNs) to enhance CLR detection accuracy. Traditionally, this task relies on expert assessment. DL emerges as a promising approach, capable of autonomously extracting salient features. Our model, trained on a diverse dataset, accurately identifies CLR. Using 1365 meticulously curated images, the model undergoes rigorous preprocessing and augmentation. The DL-based approach achieves remarkable accuracy (98.89%), precision (99.00%), recall (98.07%), and an F1 score of (98.55%). These outcomes establish the CNN model as a proficient system for precise, real-time CLR diagnosis. This study contributes to the creation of an efficient system, safeguarding coffee orchard vitality and productivity.

Morphological and molecular characterization of the rust fungus, Phakopsora apoda causing leaf rust on Brachiaria grass in Rwanda

Brachiaria grass is one of the major forages that plays a key role in push pull technology. Different diseases including leaf rust caused by rust fungus, Phakopsora apoda have recently become an important challenge resulting in yield loss of Brachiaria grass in different countries including Rwanda. The objective of this study was to provide morphological and molecular characteristics of Phakopsora apoda causing Brachiaria leaf rust. Spores isolated from rusted Brachiaria leaves collected in five districts of Rwanda were analyzed. Samples were put in paper bags and left at room temperature for two days. Thereafter, spores were removed using brushes and put in eppendorf tubes, stored at 4oC in darkness for further characterization. For morphological characteristics, colour and measurements of spores were recorded using Optika B-350 microscope with installed camera and calibrated micrometer. Multigene analysis using rust specific primers and large subunit (LSU) of nuclear ribosomal RNA was performed for molecular characterization. The results indicated that the colour of spores was yellowish or brownish while the shape was ellipsoidal or circular with average measurements of 25.1µm and 16.8µm for length and width respectively. Primers amplified the size of DNA between 1291bp and 1381bp and the size between 874bp to 882bp for rust specific primers and LSU respectively. The identity of the sequence was 96% with e-value of 0, sequence coverage of 60% for rust primer and the sequence identity was 94.97% to 95.37%, sequence coverage of 99% to 100% and e-value of 0 for LSU primer. All sequences recovered from five isolates of leaf rust matched to the genebank accession number MG461668.1 for both rust specific and LSU sequences. The results of this study provide useful information to develop effective options for leaf rust disease management in Rwanda. Key words: Internal transcribed spacer, large subunit, nuclear ribosomal RNA, Phakopsora apoda, sequence, spore.

The Effects of Fungicides and Bioagents on Rust (Uromyces setaria) Disease Management in Foxtail Millet

Rust disease caused by Uromyces Setaria is a serious airborne disease of foxtail millet that causes a considerable reduction in grain yield under severe infection. An attempt was made to manage the rust disease using fungicides, natural formulations and bioagents under field conditions. The present investigation was undertaken at the Regional Agricultural Research Station (ANGRAU), Nandyal, Andhra Pradesh, India to evaluate different fungicides (six), natural formulations (two) and bioagent (one)for effective management of rust disease for three consecutive rabi seasons during 2018-19, 2019-20 and 2020-21. The experimental results indicated that the least percent disease index of 7.9 per cent was recorded with Hexaconazole (0.2%) and mean grain yield (1,585 kg/ha) with a 46.25 percent improvement in grain yield when compared with untreated control over three years of data. It was followed by 8.0 percent disease control achieved in continuous spray with Mancozeb at 10 days interval starting 30 days after sowing, which resulted in a 46.25 percent increase in grain yield (1,585 kg/ha) and Difenoconazole 25EC (Score @ 0.1 percent) with a percent disease index of 9.03 per cent and a 46.82 percent increase in grain yield (1,602 kg/ha). The natural formulations and bioagent has shown to be least effective in controlling rust disease compared to chemical fungicides, Among these, Neem seed Kernel Extract (5%) was found to be better with PDI of 25.1% compared other two treatments (Butter milk + Asafoetida and Pseudomonas fluorescens @10g/l. Two fungicides, i.e Difenoconazole and Hexaconazole were proven to be successful in reducing rust and offering marginal farmers in a cost-effective mode.The findings could aid in the development of rust management strategies in India, such as fungicide rotation and strategic fungicide treatment.

Long-Distance Transport of Puccinia striiformis f. sp. tritici by Upper Airflow on the Yunnan-Guizhou Plateau Disrupts the Balance of Agricultural Ecology in Central China.

Long-distance dispersal of plant pathogens in the air can establish diseases in other areas and lead to an increased risk of large-scale epidemics. Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat in China. Hubei is an important overwintering region for Pst in China, and this overwintering region is a determinant of stripe rust severity in eastern China. In 2017, stripe rust disease caused a pandemic in the Hubei region and resulted in great yield losses of wheat. To explain the disease pandemic, a total of 595 single-lesion samples of stripe rust were collected in spring, including 204 in five provinces in 2017 and 391 in four provinces in 2018, and genotyped with 13 simple sequence repeat makers. The samples were classified into 12 subpopulations based on the locations and year of collection. Genetic diversity was determined for the collection and each subpopulation. Differentiation and gene flow were determined between subpopulations. STRUCTURE analyses and discriminant analysis of principal components were conducted, and the results were used to infer the relationships between subpopulations. Our study revealed a new route of Pst transmission from the Yunnan-Guizhou Plateau to the Hubei region. The Pst inoculum of northwestern Hubei came from Gansu in the northwest, whereas the inoculum in southern Hubei came from the Yunnan-Guizhou Plateau via upper airflow. After the initial inocula infected wheat plants and multiplied in northern and southern Hubei, urediniospores produced in these regions further spread together along the middle reach of Hanshui Valley and made exchanges there. The finding of the new transmission route of Pst is important for improving integrated stripe rust disease management, which should have a profound impact on the balance of agricultural ecology in China.

Differential response of phytohormone signalling network determines nonhost resistance in rice during wheat stem rust (Puccinia graminis f. sp. tritici) colonization

AbstractStem rust caused by Puccinia graminis f. sp. tritici is one of the most devastating diseases of wheat. Breakdown of host resistance under field conditions triggered by the evolution of new pathogenic races and pathotypes is a perennial threat for wheat cultivation. Rice, often grown in a rice–wheat cropping system, is immune to rust infection. Our microscopic studies revealed that P. graminis f. sp. tritici, although displaying nearly identical uredospore germination, stomatal entry, and epi‐ and endophytic mycelial growth in rice and wheat, failed to sporulate to cause rust disease in rice. We identified 18 key defence signalling genes in rice and unravelled their elicitation dynamics in time‐course studies during infection. ICS1, NPR1‐3, PRs, EDS1, PAD4, FMO1 (salicylic acid [SA] signalling), and ethylene‐related genes (ACO4 and ACS6) were strongly elicited in rice. However, genes from the jasmonic acid (JA) signalling pathway (LOX2, AOS2, MYC2, PDF2.2, JAZ8, JAZ10) showed a delayed response during colonization in rice compared to an early or no induction in wheat. However, the JA/ethylene marker gene PDF2.2 was strongly induced in wheat as early as 12 hr postinoculation. Furthermore, rice and wheat displayed specific profiles of accumulation of various phenolic acids during P. graminis f. sp. tritici 40A infection. We propose a model where a differential modulation of the SA/JA‐dependent defence network may modulate nonhost resistance. A deeper understanding of the molecular mechanism governing differential elicitation of defence signalling may provide a novel resistance mechanism for the sustainable management of rust diseases.

Evaluation of Castor Bean Varieties and Fungicides Application to Control Rust (<i>Melampsoraricini</i>) Disease

Castor bean (Ricinus communis L.) cultivation is affected by different abiotic and biotic factor constraints. Among the biotic factors rust caused by <i>Melampsoraricini</i> attack castor at young to old stage cause drying of leaves. It caused 60% of disease incidence and 30% of severity at Wondo Genet agricultural research center. The present study was undertaken to determine the efficacy of different fungicides with Castor bean varieties under field condition for the management of rust disease. Two registered varieties (Abaro and Hiruy), three registered fungicides (propiconazol 25%) (Atracole 32 SC), tebuconazole (Tilt 250 EC), triadimefon (Diprocon) and two controls with no spray treatments were used. The treatments were arranged in randomized complete block design (RCBD) with three replications. The fungicides were sprayed at the recommended rate on the diseased plants at 15day interval for five rounds. Data was recorded on disease severity, disease incidence, plant height, branch number and seed yield (kg)/ha). Among the treatments, Hiruy variety treated with Diprocon (DC=87.6%) was effective fungicides against castor rust disease control whereas, Abaro variety treated with Tilt (DC=60.1%) and Altracole (DC=60.1%) significantly controlled the rust disease under field condition. Thus, the susceptible variety with different fungicides and plant extracts should be studied further for integrated management of castor bean rust.

Wheat Leaf Rust Disease Management: A Review

Leaf rust is one of the three wheat rusts and is economically important disease of wheat worldwide. It is a devastating disease that can cause significant yield losses especially in wheat growing regions of the world where environmental conditions are conducive. In Ethiopia, wheat leaf rust is one of the most important diseases in most wheat growing areas of the country where the yield loss due to its impact is reaching up to 75% in susceptible wheat varieties at hot spot areas. This review discusses recent information on economic importance, epidemiology, geographic distribution, life cycle, host range of wheat leaf rust disease as well as its management methods such as cultural, chemical, biological and use of host resistance cultivars. Under the use of host resistance method, information on the types of resistance and sources of resistance has been presented.

Wheat Stripe Rust Grading by Deep Learning With Attention Mechanism and Images From Mobile Devices.

Wheat stripe rust is one of the main wheat diseases worldwide, which has significantly adverse effects on wheat yield and quality, posing serious threats on food security. Disease severity grading plays a paramount role in stripe rust disease management including breeding disease-resistant wheat varieties. Manual inspection is time-consuming, labor-intensive and prone to human errors, therefore, there is a clearly urgent need to develop more effective and efficient disease grading strategy by using automated approaches. However, the differences between wheat leaves of different levels of stripe rust infection are usually tiny and subtle, and, as a result, ordinary deep learning networks fail to achieve satisfying performance. By formulating this challenge as a fine-grained image classification problem, this study proposes a novel deep learning network C-DenseNet which embeds Convolutional Block Attention Module (CBAM) in the densely connected convolutional network (DenseNet). The performance of C-DenseNet and its variants is demonstrated via a newly collected wheat stripe rust grading dataset (WSRgrading dataset) at Northwest A&F University, Shaanxi Province, China, which contains a total of 5,242 wheat leaf images with 6 levels of stripe rust infection. The dataset was collected by using various mobile devices in the natural field condition. Comparative experiments show that C-DenseNet with a test accuracy of 97.99% outperforms the classical DenseNet (92.53%) and ResNet (73.43%). GradCAM++ network visualization also shows that C-DenseNet is able to pay more attention to the key areas in making the decision. It is concluded that C-DenseNet with an attention mechanism is suitable for wheat stripe rust disease grading in field conditions.

Fungicide chemicals for the integrated management of rust disease in chickpea

Chickpea is one of the major pulse crop affected by various diseases, the rust caused by (Uromyces ciceris-arietini) (Grogon) Jacz. & Boyer is considered as one of the most distructive disease of chickpea. Rust pathogen affects in all growth stages results in substantial losses in terms of both quality and quantity parameters of grain and this reinforces the need to exploit several management strategies including chemical control. Therefore, present investigation was carried out to examine the efficacy of total of twelve chemicals fungicides alone and/or in combination against rust disease of chickpea in two independent locations viz., Arabhavi and Dharwad during 2017-18. The field experiment consisting of three replication and thirteen treatments. The results of the experiment revealed that all the twelve fungicides tested were found effective for the management of chickpea rust disease as compare to control (water spray). However spray combination of Tebuconazole 50% + Trifloxystrobin 25% w/w 75 WG @ 1.0 g/l twice at onset of disease significantly reduced rust incidence with record of 14.28 PDI with high total yield of 12.36 qtl/ha followed by Tebuconazole 25 EC @1 ml/l recorded 15.72 PDI with yield of 12.22qtl/ha, Propioconazole 25EC @1.0 ml/lit (Tilt) recorded 16.41 PDI with higher yield of 11.17 qtl/ha) found effective in reducing the disease. While, Difenoconazole 25 EC@1 ml/l showed 17.45 PDI and yield of 10.56qtl/ha, Tebuconazole 50% + Trifloxystrobin 25% w/w 75WG @ 0.5 g/l recorded 18.25 PDI and 10.36qtl/ha of yield and Pyraclostrobin 25 EC @1 ml/l observed with 20.02 rust PDI with yield of 10.32qtl/ha showing equally effective in reducing rust percent disease incidence and increased yield when compared to control that recorded highest rust disease incidence (53.71 PDI) and lower yield (6.16 qtl/ha).

Role of Alternate Hosts in Epidemiology and Pathogen Variation of Cereal Rusts.

Cereal rusts, caused by obligate and biotrophic fungi in the genus Puccinia, are important diseases that threaten world food security. With the recent discovery of alternate hosts for the stripe rust fungus (Puccinia striiformis), all cereal rust fungi are now known to be heteroecious, requiring two distinct plant species serving as primary or alternate hosts to complete their sexual life cycle. The roles of the alternate hosts in disease epidemiology and pathogen variation vary greatly from species to species and from region to region because of different climatic and cropping conditions. We focus this review on rust fungi of small grains, mainly stripe rust, stem rust, leaf rust, and crown rust of wheat, barley, oat, rye, and triticale, with emphases on the contributions of alternate hosts to the development and management of rust diseases.

Impact of plant protection activities on production and productivity of crops in Jammu region (J&amp;K), India

Impact of Plant Protection Activities on Production and Productivity of Crops in Jammu Region (J&K), India The impact of plant protection activities conducted during 2010-11 to 2015-16 was studied based on individual interactions as well as Focused Group Discussion (FGD) of 100 farmers in Reasi district of J&k, India. Their response to a pre-defined questionnaire indicated that the activities enhanced the intensity of crop substitution, escalated Seed Replacement Rate (SRR) with intensification of input use. Improved crop production and productivity with reduced production cost and also enhanced profit margin with other short term effect of the programmes. Under performance of technologies tested in OFTs for management of Chili wilt diseases was recorded 22.5% less disease incidence with 24.5% yield advantage over control, 20% yield enhanced over control in management of red pumpkin beetle in bottle gourd, 25% less rotting with 35%yield advantage over control in IDM module for rhizome rot management in ginger, 10.5% additional yield over control in loose smut disease management in wheat and 45.5% additional yield over control in yellow rust disease management in wheat. Performance of Front Line Demonstrations on plant protection activities conducted by KVK, Reasi during 2010- 11 to 2015-16 showed 15.5% more yield than the local practice no spraying of pesticides with reduced wilt incidence under IDM for wilt management in tomato. The demonstration has exhibited 25.5% more yield than the local practice (not use of pesticides) of IDM in Chilli wilt, the demonstrated fungicides exhibited 20.5% higher yield than un sprayed crop under yellow rust disease management in wheat. The varieties i.e. PBW-175 exhibited 25.5% higher yield than the local check under yellow rust disease of wheat tolerant varieties. The demonstration has exhibited 34.5% more yield than the local practice under IDM modules for rhizome rot management in ginger. Under plant protection activities on productivity of crops over time under rainfed condition exhibited in maize in 2010-11 there was only 14 qt/ha yields of maize var. Double Deklab which increased up to 26 qt/ha in 2015-16 after KVK interventions. So, there was increased 85.71 % in the yield. Similarly, there was enhanced 71.42% yield of maize var. Bio seed in the same duration. There was enhanced in 64.28% and 85.71 % of wheat yield of varieties PBW-175 and Raj- 3765 respectively during the same period. The increase in yield of mash variety Uttara was 37.50%, lentil var. L-4147 65.71%, mustard var. RSPR-01 51.11% and Oat var. Kent 86.25% respectively in the same year. Development of professionalism and entrepreneurship resulting in enriched socio economic status of farmers were also indicated. The productivity of crops was found to be influenced ..

Mapping of quantitative adult plant field resistance to leaf rust and stripe rust in two European winter wheat populations reveals co-location of three QTL conferring resistance to both rust pathogens.

Key message We detected several, most likely novel QTL for adult plant resistance to rusts. Notably three QTL improved resistance to leaf rust and stripe rust simultaneously indicating broad spectrum resistance QTL. The rusts of wheat (Puccinia spp.) are destructive fungal wheat diseases. The deployment of resistant cultivars plays a central role in integrated rust disease management. Durability of resistance would be preferred, but is difficult to analyse. The Austrian winter wheat cultivar Capo was released in the 1989 and grown on a large acreage during more than two decades and maintained a good level of quantitative leaf rust and stripe rust resistance. Two bi-parental mapping populations: Capo × Arina and Capo × Furore were tested in multiple environments for severity of leaf rust and stripe rust at the adult plant stage in replicated field experiments. Quantitative trait loci associated with leaf rust and stripe rust severity were mapped using DArT and SSR markers. Five QTL were detected in multiple environments associated with resistance to leaf rust designated as QLr.ifa-2AL, QLr.ifa-2BL, QLr.ifa-2BS, QLr.ifa-3BS, and QLr.ifa-5BL, and five for resistance to stripe rust QYr.ifa-2AL, QYr.ifa-2BL, QYr.ifa-3AS, QYr.ifa-3BS, and QYr.ifa-5A. For all QTL apart from two (QYr.ifa-3AS, QLr.ifa-5BL) Capo contributed the resistance improving allele. The leaf rust and stripe rust resistance QTL on 2AL, 2BL and 3BS mapped to the same chromosome positions, indicating either closely linked genes or pleiotropic gene action. These three multiple disease resistance QTL (QLr.ifa-2AL/QYr.ifa-2AL, QLr.ifa.2BL/QYr.ifa-2BL, QLr.ifa-3BS/QYr.ifa.3BS) potentially contribute novel resistance sources for stripe rust and leaf rust. The long-lasting resistance of Capo apparently rests upon a combination of several genes. The described germplasm, QTL and markers are applicable for simultaneous resistance improvement against leaf rust and stripe rust.Electronic supplementary materialThe online version of this article (doi:10.1007/s00122-014-2357-0) contains supplementary material, which is available to authorized users.