Use Of Resistant Varieties Research Articles

Evaluation the durable resistance of soybean varieties toward leaf rust caused by Phakopsora pachyrhizi

The main disease of soybean plants is leaf rust caused by the fungus Phakopsora pachyrhizi which can cause a decrease in the yield of up to 60% and has the potential to reduce seed quality. The use of resistant varieties is the main component of rust disease control. The purpose of this research was to determine the resistance level of several soybean varieties to the rust disease caused by Phakopsora pachyrhizi and its effect on the production of each variety. To evaluate the resistance reaction of soybean varieties to rust disease, the IWGSR system was used, as the intensity level of the disease and its effect on the production of each tested soybean variety. The results showed that the Detap 1 variety counted the lowest disease intensity of 22.84% with a susceptible disease reaction and had high productivity, followed by the Agromulyo, Anjasmoro, and Devon 1 varieties which categorized a mildly susceptible disease reaction with a disease intensity of 25.34%, 27.46%, and 28.70% respectively. The Derap 1 and Edamame varieties have a high disease intensity of 35.18% and 29.31% with susceptible disease reactions. The production of the highest number of pods was the Agromulyo variety.

Control of Pepper yellow leaf curl Indonesia virus and Its Vector (Bemisia tabaci Genn.) on Chili Plants (Capsicum annum L.) Using Resistant Variety and Insecticide Application

PepYLCIV, the cause of chili yellow leaf curl disease, is currently widespread in Indonesia and cause up to 100% yield loss, transmitted by whitefly, namely Bemisia tabaci. The purpose of the current study was to determine the effect of using chili varieties with different resistance to Geminivirus and different frequencies of insecticides application on B. tabaci population, PepYLCIV incidence and severity on two chili varieties with different resistance to Geminivirus. The experimental design used was a Split Plot Design. The main plots were chili varieties consisting of Baja MC F1 and Pilar F1. Sub-plots were the frequency of insecticides application which consisted of three levels, those are: not applied, applied once a week, and applied twice a week. Parameters observed were B. tabaci population, disease incidence and severity which carried out every week (starting 23 days after planting). The results showed, the use of insecticides and varieties with different resistance to Geminivirus had no effect on suppressing B. tabaci populations during the rainy season. Thus, chili plants didn’t need insecticides application during the rainy season. The use of resistant varieties can reduce the incidence and severity of chili yellow leaf curl disease, but both varieties reacted similarly to B. tabaci.

Management of Fungal Diseases of Temperate Rice in the Kashmir Valley, India

Over half of the world's population is fed by rice. It is consumed as a staple food by many countries worldwide. It is affected by a number of diseases among which fungal diseases contribute to its significant loss. Kashmir Valley located in the North Western Himalayan region of India is known for various coarse varieties of rice for their taste and elite class. However, the diseases cause a serious problem for the local farmers as well as the people who also consume rice as their staple food. One of the best remedies for disease management is the adoption of integrated disease management strategies, which include the use of resistant varieties, cultural practices, and judicious use of fungicides. In this review, we present the major fungal diseases affecting rice in Kashmir Valley and their management using Integrated Plant Disease Management (IDM).

A Comprehensive Assessment of Verticillium Wilt of Potato: Present Status and Future Prospective

The fungal disease Verticillium wilt is a soil-borne pathogen that is caused by Verticillium dahliae. This disease affects a wide range of crops and can cause significant yield losses. Recent findings suggest that Verticillium wilt has been affecting potato crops in abundant domains around the global world, including in North America, parts of Europe, and Asia. In some cases, the disease has been observed in fields where it has not been previously reported, indicating that it has been spreading. Farmers and researchers are working to manage the disease through a variety of measures, including rotation of crops, the use of resistant varieties of potato developed from resistant strains, and the application of fungicides. However, the potency of these measures can vary depending on the ferocity of the disease and the local growing circumstances. Overall, the recent findings of Verticillium wilt in potato underscore the importance of continued monitoring and research to better understand the disease and develop effective management strategies. This review has highlighted the up-to-date information on Verticillium wilt and management strategies. The study also helps the scientific community understand this devastating plant disease by offering a thorough review of the situation.

A COMPREHENSIVE STRATEGY FOR LATE BLIGHT MANAGEMENT IN POTATO AND TOMATO

Late blight is a highly destructive disease primarily affecting potato (Solanum tuberosum) and tomato (Solanum lycopersicum) and some other closely related crops such as aubergine, pepper, solanaceous weeds such as nightshade species, wild tomato etc. This disease is caused by fungus-like organism oomycetes also known as water mold called Phytophthora infestans. Whereas early blight of potato and tomato are caused by fungus Alternaria solani and Alternaria tomatophila respectively. Heinrich Anton De Bary, the father of modern plant pathology studied the epidemics of Late Blight in 1863 and renamed the causal organism Phytophthora infestans (infectious plant destroyer). The disease is severe in areas with high humidity and rainfall and spreads through wind, rain, or contaminated plant material capable of causing entire crop failure if left uncontrolled. Late blight affects foliage, fruit, and tuber and its symptoms include dark, water-soaked lesions on the stem, leaves, and fruit which can rapidly develop into brown, necrotic areas ultimately leading to plant death. Control measures for late blight includes crop rotation, the use of resistant varieties and the application of fungicides. However, the emergence of more virulent strains of Phytophthora infestans and the development of resistance to fungicide application pose ongoing challenges to effective disease management. This paper reviews the current knowledge on management strategies for late blight focusing on integrated disease management approaches. Furthermore, the challenges and prospects of integrated management strategies are discussed.

Effect of soybean variety and pest management on the sustainable production

Pests are one of the limiting factors in increasing soybean production. Pest control carried out by farmers using pesticides is feared to threaten the sustainability of soybean production in Indonesia. This study aimed to identify the effect of different pest management systems and various soybean varieties on pest population dynamics, abundance and diversity of natural enemies, plant damage, and soybean production. A split plot design with three replications was applied, where the main plot was pest management systems i.e. (1) control (which received neither chemicals nor integrated pest management), (2) chemical control, and (3) integrated pest management, and the sub-plot was soybean varieties i.e. (1) Anjasmoro, (2) Demas 1, and (3) Dering 1. Results indicated that variety affects pest diversity and abundance, however, it affected leaf damage, pod damage, and production. The pest management systems influenced the diversity and abundance of pests and natural enemies, plant damage, and production. Interaction between variety and pest management system affected plant damage. We conclude that the use of resistant varieties combined with integrated pest management could reduce plant damage, maintain the natural enemy population, and optimize soybean production.

Sources of strawberry resistance to late blight leathery rot for the Middle Urals

The results of the study of strawberry hybrids for further breeding in the period of mass spread of diseases contributing to the shortage of berry products - gray and late blight leathery rot of berries - are presented. The studies were carried out in a field experiment at the Sverdlovsk Horticultural Breeding Station on the collection of live plants in the open ground in 2018-2021. The objects of the study are eight elite hybrids of medium and late maturity, originating from the families Solovushka x Totem, Solovushka x Dukat, Solovushka x Marmolada, Amulet x Marmolada. The check varieties are Geyser and Borovitskaya. The hybrids were studied in accordance with the generally accepted methods for the complex of economically valuable characters and the degree of infestation by the fungal disease. In the conditions of the Urals, gray rot is observed almost annually, and the late blight on berries - in some years. In the years favorable for the development of the late blight, yield losses in the varieties that are not resistant to the disease of medium and medium maturity dates can be significant. In the Middle Urals, the disease is also observed on the late varieties of strawberries. It was found that resistance to late blight leathery rot is controlled polygenetically through the additive effect of several genes and does not depend on the races of the pathogen. Since there is no immunity to this disease in strawberries, work was carried out with the use of resistant varieties isolated when studied in the field. As a result of the research the resistant (with yield loss up to 10%) medium-maturing hybrids 2-45-10 and 2-54-11 were identified, which will be involved in the breeding process for the trait of resistance to late blight leathery rot.

Cultivar Resistance of Korean Breeding Cut-Rose against Crown Gall by Agrobacterium tumefaciens Evaluated by an In Vitro Inoculation

Rose crown gall caused by Agrobacterium tumefaciens is a major disease that damages the production of cut-roses in Korea. The effective prevention methods for this disease include the use of resistant varieties. This study was conducted to evaluate the resistance of 58 Korean cultivars and six foreign cultivars to crown gall disease with nodal explants in vitro. Among 180 A. tumefaciens strains, pathogenic strain RC12 was selected as an inoculant strain. The strain RC12 was identified based on characteristics of some selective media, pathogenicity test, and polymerase chain reaction analysis. Forty rose cultivars formed tumors on explants inoculated with A. tumefaciens RC12. However, 24 cultivars, including 22 Korean cultivars and 2 foreign cultivars, showed resistance to A. tumefaciens RC12 without forming any tumors. Six cultivars with tumor formation rates of over 30% formed initial tumors within 23 days after inoculation. Six cultivars with low tumor formation rates of around 5% formed initial tumors after 28 days of inoculation. It was found that gall formation rate was highly correlated with the initial gall formation period. Thus, the relationship between the period of gall formation and the rate of gall formation could be useful for assessing resistance to crown gall disease. In vitro inoculation methods could be used to evaluate resistance of cut-rose cultivars to crown gall diseases.

A novel study on bean common mosaic virus accumulation shows disease resistance at the initial stage of infection in Phaseolus vulgaris.

Accurate and early diagnosis of bean common mosaic virus (BCMV) in Phaseolus vulgaris tissues is critical since the pathogen can spread easily and have long-term detrimental effects on bean production. The use of resistant varieties is a key factor in the management activities of BCMV. The study reported here describes the development and application of a novel SYBR Green-based quantitative real-time PCR (qRT-PCR) assay targeting the coat protein gene to determine the host sensitivity to the specific NL-4 strain of BCMV. The technique showed high specificity, validated by melting curve analysis, without cross-reaction. Further, the symptoms development of twenty advanced common bean genotypes after mechanical BCMV-NL-4 infection was evaluated and compared. The results showed that common bean genotypes exhibit varying levels of host susceptibility to this BCMV strain. The YLV-14 and BRS-22 genotypes were determined as the most resistant and susceptible genotypes, respectively, in terms of aggressiveness of symptoms. The accumulation of BCMV was analyzed in the resistant and susceptible genotypes 3, 6, and 9days following the inoculation by the newly developed qRT-PCR. The mean cycle threshold (Ct) values showed that the viral titer was significantly lower in YLV-14, which was evident in both root and leaf 3days after the inoculation. The qRT-PCR thus facilitated an accurate, specific, and feasible assessment of BCMV accumulation in bean tissues even in low virus titers, allowing novel clues in selecting resistant genotypes in the early stages of infection, which is critical for disease management. To the best of our knowledge, this is the first study of a successfully performed qRT-PCR to estimate BCMV quantification.

Molecular Identification of I-3 gene, a Fusarium wilt resistant marker in selected varieties of tomato

Fusarium wilt is a famous disease of tomato all over the world. The use of resistant varieties is the most efficient approach to control the disease. The current study was carried out to investigate the presence of marker gene(s) resistant to Fusarium wilt in tomato germplasm, and the subsequent use of resistant varieties to contain the disease. Thirteen varieties: Pusa ruby, Pant bahar, Punjab chhahara, Arka alak, Arak abha, Ratan, CLN-2116-B, CLN-1767-238-2Y, CLSN-2123-A, CLN-1621-E, CLN-1621-T, CLN-1621-L, and CLN-2026-C were screened for the presence of I-3 resistance gene, a marker known to confer resistance to the race 2 of F. oxysporum f. sp. Lycopersici. Two varieties, Arak abha and Ratan were tested positive for the presence of I-3 against the race 2 of the pathogen.

A Review of Insect Pest Management in Vegetable Crop Production in Nigeria.

Insect pest infestations and damage can limit the production of vegetables in the farming systems in Nigeria. This review looks at integrated insect pest management as a possible panacea for resolving insect pest issues in vegetable crops. The main vegetable crops which include okra, tomatoes, chilli peppers, cucumbers, green amaranth, carrots and onions are highlighted. The major insect pests of the various vegetables which include foliage beetles, caterpillars, aphids, fruit flies, stink bugs, and grasshoppers are also mentioned. The various control measures that have been empirically verified for the mitigation of the impact of these insect pests, including the application of synthetic insecticides, modification of agronomic practices, use of resistant varieties, application of botanicals, biological and mechanical controls, are discussed. Studies which have been carried out attempting to integrate two or more of the control strategies for better insect pest control are also reviewed. Strategies that can be put in place for the integrated pest management of vegetable insect pests in Nigeria are considered. Among the IPM (Integrated Pest Management) practices instituted for the mitigation of pest infestations on vegetable crops in Nigeria, intercropping of suitable vegetables in combination with the application of aqueous extracts of Azadirachta indica and Piper guineense seeds under good farm hygiene and sanitation proved to be most successful.

Desempenho de variedades das uvas resistentes (PIWI), 'Felicia', 'Calardis Blanc' e 'Helios' produzidas em dois locais do estado de Santa Catarina (BR)

ABSTRACT Downy mildew (Plamopora viticola) is one of the major problems to produce wine grapes in Brazil, a main cause of yield losses in the Southern region of the country. An alternative to the use of pesticides is the use of resistant varieties (PIWI): wine grapes combining high oenological potential and resistance to diseases. The goal of this work was to assess the vegetative and productive performance and maturation of three PIWI varieties (‘Felicia’, ‘Calardis Blanc’ and ‘Helios’) produced at altitudes of 840m and 1250m in the 2020, 2021 and 2022 vintages. The study is focused on four phenological stages: budbreak (BBCH 7), full bloom (BBCH 65), veraison (BBCH 81) and maturity/harvest (BBCH 89). The criteria for measuring the productive performance were, the number of clusters, average cluster weight, production per plant, yield and Ravaz index. As parameters for technological and phenolic maturation, pH, soluble solids, total acidity and total polyphenols were evaluated. The budbreak occurred at the end of August until the second fortnight of September, the flowering occurred in the second week of October, the veraison occurred during the month of December, and the maturity/harvest occurred from the second fortnight of January until the beginning of February. The earliest budbreak occurred with ‘Felicia’ in the vineyard at 1250m and the latest occurred with ‘Calardis Blanc’. Regardless of the vineyard altitude, there was practically no difference in the flowering date between varieties and the vineyards altitude, the veraison and the maturity/harvest occurred earlier in the vineyard at 840m. The varieties produced at 840 m had a shorter cycle and proved to be more productive when compared to those produced at 1250 m. The studied varieties showed good phenological adaptation, high yield and maturation indices suitable for the production of quality still and sparkling white wines at both altitudes. From the results obtained, ‘Felicia’ and ‘Calardis Blanc’ seem to be the most promising varieties for cultivation in both altitude ranges.

Near-isogenic lines for resistance to brown planthopper with the genetic background of Indica Group elite rice (Oryza sativa L.) variety 'IR64'.

The brown planthopper (BPH), Nilaparvata lugens Stål, is an insect pest that severely damages rice (Oryza sativa L.) in Asia, causing huge yield loss. Use of resistant variety is a cost-effective and eco-friendly strategy for maintaining BPH populations below the economic injury level. However, current BPH populations have been changed to virulence against resistant varieties. In this study, to estimate effective combinations among eight BPH resistance genes (BPH32, BPH17-ptb, BPH20, BPH17, BPH3, BPH25, BPH26 and qBPH6), eight near-isogenic lines with the genetic background of an Indica Group rice variety 'IR64' (IR64-NIL) were developed using marker-assisted selection. The genome recoveries of these NILs ranged from 89.3% to 98.8% and agronomic traits of them were similar to those of 'IR64'. In modified seed box screening test, resistance level of IR64-NILs was higher than that of 'IR64'. In antibiosis test, high adult mortalities of BPH (from 56.0% to 97.0%) were observed among NILs, in comparison with that of 'IR64'. Among IR64-NILs, the line carrying BPH17 showed the highest resistance level at all tests. Thus, these IR64-NILs with multiple BPH resistance genes could be valuable breeding lines for enhancing resistance levels by gene pyramiding and multiline variety.

Resistance Assessment of Hybrid Corn Genotypes to Major Corn Diseases and Its Effects on Disease Epidemic Components in South Sulawesi, Indonesia

The use of resistant varieties is one of approach that can be used in the management of the pathogen development. This study aimed to examine the resistance level of hybrid corn genotypes to the corn major diseases and to determine its effect on the components of the disease epidemic. Testing for the three major diseases was carried out using spreader row plants as an inoculum source. Parameters observed in this study were disease incidence for downly mildew (DM), disease severity for maydis leaf blight (MLB) and leaf rust (LR), disease development model, infection rate, area under the disease progress curve (AUDPC), protection index, and path analysis. The results showed that the HBC01 genotype had the lowest attack intensity to DM, MLB, and LR, namely 35.55%, 37.33%, and 25.33%, respectively. The disease epidemic components also showed that the HCB01 genotype has the lowest AUDPC value and infection rate with the highest protection index against DM, MLB, and LR. Furthermore, relative humidity, temperature, rainfall, and wind velocity were correlated in influencing the development of DM, MLB, and LR. The conclusion is that the hybrid corn genotype greatly influences the development of epidemics of DM, MLB, and LR.

Sugarcane streak mosaic virus (ScSMV) Resistance Evaluation of Sugarcane Varieties

Sugarcane streak mosaic virus (ScSMV) is the most important viral disease of sugarcane in Indonesia with distribution in almost all commercial sugarcane plantations. The disease causes significant yield losses of both cane tonnage and sugar yield. The use of resistant varieties is the best approach for controlling viral diseases. This study aims to investigate resistance response of several introduced varieties against ScSMV in a glasshouse condition and the impact of the viral infection on chlorophyll and proline content in sugarcane leaves. Sugarcane plants were inoculated using ScSMV inoculum one month after planting using an abrasive pad rubbing method. Disease incidence and severity was observed at week 4-12 after inoculation and variety resistance levels were classified based on disease incidence. Confirmation of the virus was done by RT-PCR. Spectrophotometer was used to measure chlorophyll content at dual wavelengths of 645 and 663 nm, and proline content at wavelengths of 520 nm. The results showed that most of the tested varieties were susceptible to ScSMV. There are six highly resistant varieties, namely SRA 1, SRA 2, N 10-4, N 10-7, N10-9, and N 10-13, but these varieties still require to be tested on a field scale. ScSMV infection generally decrease chlorophyll and proline content. However, the physiological effect of ScSMV infection on chlorophyll and proline content needs further investigation.

Microbial network and composition changes according to tobacco varieties and interferes differently in black shank disease defense.

The soil-borne oomycete pathogen Phytophthora parasitica can cause black shank disease in tobacco plants. The use of resistant varieties can be used to control black shank disease. The potential relationships of the composition of the rhizosphere microbiome to resistance to black shank disease are poorly understood. This work aims to compare the rhizosphere microbial community and network of the tobacco resistant variety HB202 with the susceptible variety XY3. Rhizospheric soils were collected from tobacco plants of HB202 and XY3 in the fields with same soil types and agricultural operations. The compositions of the rhizosphere microbial communities were revealed by Illumina sequencing of bacterial 16S rRNA genes and fungal spacer (ITS) sequences and analysed with molecular ecological network pipeline. The alpha diversity of fungal communities of the two varieties was significantly different. The structure and composition of bacterial and fungal communities in the resistant variety in the rhizosphere was different from the susceptible variety. Relative abundances of beneficial genera in the HB202 microbiota were higher than in the XY3. Conversely, the XY3 microbiota exhibited a higher abundance of deleterious genera compared to the HB202 microbiota. The resistant variety influences the topological properties and microbial interactions in the rhizosphere against the disease. The network of the HB202 was more complex and had higher connectivity compared to the XY3 network. The rhizosphere microbial communities and networks of two tobacco varieties are very different. These changes in the microbial communities and their interactions may play an important role in tobacco resistance to black shank disease.

Antiviral Activity of TiO2 NPs against Tobacco Mosaic Virus in Chili Pepper (Capsicum annuum L.)

Tobacco mosaic virus is the etiological agent of one of the most critical diseases limiting chili pepper production. Various practices have been used to manage the disease, e.g., the use of resistant varieties and interference with the vector through chemical control. However, these practices are not helpful once the virus has been established in the plant. There is still no effective method for the sustainable management of the disease; therefore, exploring new options is required. Currently, some studies have reported the activity of TiO2 NPs against viruses in plants, although not against TMV in chili pepper. The present work aims to determine a possible direct action of TiO2 NPs against TMV and if there is a relationship between the amount of virus and symptoms. The application of TiO2 NPs at 150 μg/mL in infected pepper plants reduced symptoms and viral load and improved the morphological characteristics compared to the control. Incubation of 150 µg/mL TiO2 NPs with the virus for 6 and 8 h before infection decreased viral concentration significantly after infection compared to the control. In this work, it is reported, for the first time, that the use of TiO2 NPs is a novel practice for the control of TMV in chili pepper.

AN OVERVIEW OF WHITE ROT DISEASE MANAGEMENT IN SMALL ONION

Onion (Allium cepa) is a remunerative and high value vegetable crop in India but it has affected by several disease of fungi, bacteria, virus and nematodes. In this case fungal disease, white rot is caused by Stromatinia cepivora (Sclerotia cepivorum) is a major issue for both farmers and researchers. This disease causes heavy yield loss as its impact is more during harvesting stage and storage conditions. In this study we will analyse the causative agent of disease and various strategical approaches in recent years to control the disease incidence such as Cultural method, Biological method, Chemical method, Nanoparticles and use of resistant varieties.

Evaluation of potato genotypes against early blight (Alternaria alternata) of potato (Solanum tuberosum L.)

Early blight (Alternaria alternata) of the potato is the most destructive disease in tropical and sub-tropical countries. Natural epidemics of early blight are strongly influenced by environmental conditions, even though severe disease appears every year in northern India. Twenty-eight genotypes were used in this study to differentiate between early blight resistance and susceptible genotypes selected to represent a range of reactions when screened field conditions. Out of twenty-eight genotypes/varieties, six genotypes viz., CP-3021, 3153, Atlantic, Chip-3, Jx-161 and MS/78-62 showed a resistant reaction. While thirteen genotypes were moderately resistant. However, six genotypes were susceptible while three genotypes were highly susceptible. Resistant varieties can be the simplest, effective and economical method of plant disease control. The use of resistant varieties cannot only ensure protection against diseases but also save the time, energy and money spent on other control methods.

Investigation of Common Bean (Phaseolus vulgaris L.) Varieties in Türkiye for Resistance Sources to Angular Leaf Spot Disease (Pseudocercospora griseola)

Bu çalışmada, Türkiye'de yaygın olarak yetiştiriciliği yapılan bazı tescilli fasulye (Phaseolus vulgaris L.) çeşitlerinin köşeli yaprak lekesi hastalığı (Pseudocercospora griseola)’na karşı dayanıklılık kaynaklarının SCAR markörler (SN02, SH13 ve g2303) aracılığıyla incelenmesi amaçlanmıştır. Çalışmalar, 2020-2021 yıllarında, Ankara Üniversitesi ve Bolu Abant İzzet Baysal Üniversitesi Bitki Koruma Bölüm laboratuvarlarında gerçekleştirilmiştir. Çalışma sonucunda elde edilen bulgular, çeşitler arasında en yaygın genin Phg-2 olduğunu, bunu sırasıyla Phg-ON ve Phg-1 genlerinin izlediğini göstermiştir. Farklı gen kombinasyonları bakımından fasulye çeşitleri incelendiğinde; 18 çeşidin 1 gen, 41 çeşidin 2 gen, 5 çeşidin (Yalova-17, Boncuk, Aslan, Helda, Akman-98) ise her üç dayanıklılık genine sahip olduğu tespit edilmiştir. Tespit edilen dayanıklılık genlerinin ve kombine dayanıklılığa sahip fasulye çeşitlerinin köşeli yaprak lekesi ile ilgili yürütülecek ıslah çalışmalarına katkı sağlayabileceği öngörülmektedir.