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This article provides a comprehensive review of integrated management strategies for rhizome rot and wilt disease complex in ginger. It discusses various approaches such as soil solarization, organic amendments, cultural practices, biological control, and chemical control measures. The article emphasizes the importance of disease-free seed rhizomes and the role of bioagents in enhancing plant growth and disease resistance. It also highlights the benefits of soil solarization and soil amendments in managing soil-borne diseases. The document further explores the use of chemicals in managing ginger diseases and emphasizes the importance of integrated management strategies. It concludes that a combination of these strategies can effectively manage ginger diseases. [Extracted from the article]

Reducing post-harvest losses is a reasonable step towards food security globally. However, the lack of deep knowledge of the causes and determinants of postharvest loss poses a great challenge to strategies for alleviating postharvest loss. This study, therefore, identifies the causes and drivers of postharvest losses in onion, in Nigeria, to alleviate the menace. Data collected from 360 farmers between February and April 2021 were analyzed with descriptive statistics and a multiple regression model. Results showed that the primary causes of postharvest loss were rot, diseases and pests, drying, and bruises. While, poor storage facilities, poor transportation systems, long distances to marketing centers, poor agricultural extension services, and inadequate credit were secondary causes. The driving factors of postharvest losses in onion were extension services (β = -0.1269, p < .05), access to credit (β = -0.1054, p < .05), household size (β = -0.2650, p < .01), age of the farmer (β = 0.0557, p < .05), level of education (β = -1.0500, p < .01), farm size (β = 0.3801, p < .01), distance to market (β = 0.2187, p < .05), output (β = 0.1180, p < .01), and length of storage after harvest (β = 0.0635, p < .05). These findings call for improved transportation systems in agrarian areas, overhauling of extension services, making credit facilities available to farmers at affordable interest rates, and developing efficient post-harvest management technologies by research institutes. [ABSTRACT FROM AUTHOR]

Aims: This study aims to evaluate the effectiveness of bacteriophages isolated from Klang and Penang, Malaysia against Dickeya chrysanthemi that causes soft rot disease. Methodology and results: Basic characterization such as dextrose test, citrate test, lactose fermentation test and ornithine test were carried out on D. chrysanthemi. Activity of bacteriophages against D. chrysanthemi was evaluated using spot test. Double agar overlay assay was performed to purify and enumerate the quantify of bacteriophages. Bacteriophages were also checked for its effectiveness in controlling soft rot on post-harvested vegetables: potato (Solanum tuberosum), cucumber (Cucumis sativus) and apple (Malus domestica). Results showed that D. chrysanthemi able to utilize citrate and dextrose as the source of energy, which indicated that D. chrysanthemi inclined to choose fruits and vegetables containing citrate and dextrose as the target of attack. Clear zone observed on the bacterial lawn (spot test) indicated the ability of the bacteriophages to infect and lyse D. chrysanthemi. All the bacteriophages studied herein reached the highest concentration on day 3 and were monovalent. Conclusion, significance and impact of study: All the isolated bacteriophages were able to restrain the spreading of soft rot caused by D. chrysanthemi either work alone or as cocktail. This study provides information for the formulation development of bacteriophage against soft rot disease cause by D. chrysanthemi. Furthermore, this study reveals the potential of locally isolated bacteriophages against the D. chrysanthemi and paving the application of phage treatment on agriculture products that are not limited to potatoes, cucumber and apple. [ABSTRACT FROM AUTHOR]

Present investigation was carried out at six villages from each district were randomly selected and from each village five fields were randomly selected. Survey was conducted in area of Gwalior, Bhind and Morena districts. Systemic survey was carried out in the month of January and February (2014-15) among eighteen locations from Gwalior, Bhind and Morena districts (six locations from each district) were randomly selected in Gird zone to assess the incidence of stem rot. Findings reveal that incidence of Sclerotinia rots in Morena, Bhind and Gwalior districts were 14.21, 5.03 and 2.25%, respectively. Per cent incidence of Sclerotinia rot was recorded in northern Madhya Pradesh. Disease incidence was higher in Morena district and it varies from 18.72% to 9.36 % and maximum incidence was recorded in Dimni (18.72%) followed by Jeegni (17.68%), Morena (15.60%), and Ambah (13.52%). One location of Bhind viz, Mihona was diseased free, while its maximum incidence (11.44%) was recorded in Gauhad and Mehgoan 7.28%, followed by Bhind (6.24%) in Raun (3.12%). Maharajpura and Badagoan locations of Gwalior district are diseased free while its maximum incidence was recorded in Mohanpur (5.20%) followed by Jalalpura (3.12%). Hotspot recognized in survey for maximum disease incidence, can use as screening locations for germplasms and the disease free areas like Mihona, Maharajpura and Badagoan could be use for seed production. [ABSTRACT FROM AUTHOR]

The present studies were undertaken to investigate the effect of Composted Poultry manure amendment against root rot disease on Sunflower. Pot culture trial conducted in kharif and rabi seasons using hybrid Jaya was laid in a randomized block design with nine treatments and five replications. The sunflower crop was established by using standard cultural practices and recommended rates of fertilizers followed by State Agricultural Department. Soil and composted poultry manure amendments at rates of 5 t/ha and 10 t/ha manure by weight of soil (w/w) were mixed thoroughly for 15 min in a cement mixer and placed in pots 28, 14 and 0 days before sowing. As a comparison fungicide, carbendazim was used as seed treatment (3 g/kg of seeds) and soil drenching (500 g/ha at 60 DAS). The results revealed that, in both seasons, charcoal rot disease incidence was decreased at 10 t/ha rate of manure when incorporated 14 and 28 days before sowing and at sowing. Also, Studies on induction of defense mechanisms revealed that positive changes of total and OD phenols was observed in plants amended with composted poultry manure followed by challenge inoculation with Macrophomina phaseolina. [ABSTRACT FROM AUTHOR]

Pseudoalteromonas marina is one of the potential pathogens that cause green spot disease (GSD) in Pyropia yezoensis. To prevent GSD from development and spread, an effective method to detect the pathogen at early GSD infection stages need to be established. In this research, PCR methods were established targeting the dnaA gene (encoding chromosome replication initiator protein) and the dnaN gene (encoding β sliding clamp of DNA polymerase III protein) to detect P. marina with three primer pairs pws-dnaA2 (Forward, 5′-ACCGCATTAACGAACTACTCGTG-3′; Reverse, 5′-TGCCATTACCTACAGCATGG-3′), pcs-dnaN2 (Forward, 5′-CTTACAACGTTATCAGCGGC-3′; Reverse, 5′-GTTGAGTATTAAGTGATTGAGTAAGC-3′) or pws-dnaN3 (Forward, 5′-ACTTACAACGTTATCAGCGGC-3′; Reverse, 5′-ACTGCTGTTTGAGTCTGCTAAC-3′). Three PCR methods corresponding to the three primer pairs sufficiently distinguished P. marina from 22 bacterial species, thus resulting in detection limits of 4 to 4×102 CFU cells or 2.37×101 to 2.37×103 fg of P. marina DNA per PCR reaction. In an artificial infection experiment of P. yezoensis infected with P. marina, all established PCRs successfully detected P. marina at early GSD infection stages. The results show that the established PCRs are specific and sensitive, and are potential for applications in early diagnosis of GSD in Pyropia. [ABSTRACT FROM AUTHOR]

Aims: As a natural antimicrobial agent, Melaleuca alternifolia oil (MAO) is generally recognized to be safe and effective in the inhibition of phytopathogenic fungi. Due to lack of comprehensive studies on MAO for controlling postharvest Aspergillus, we investigated the preservative mechanism of MAO and its components against Aspergillus ochraceus in postharvest grapes to evaluate their potential effectiveness as fruit preservatives. Methods and Results: In our study, the compositions in MAO were analysed by gas chromatography–mass spectrometry. The inhibitory effects of MAO and its main constituents against A. ochraceus were compared by scanning electron microscopy and transmission electron microscopy observation, and metabolic analysis. Two components of MAO, α‐terpineol and terpene‐4‐alcohol, showed higher antifungal effects than MAO, of which α‐terpineol caused the worst leakage of cytoplasm and most serious hyphae distortions and spore disruptions. The downregulation of metabolic pathways of A. ochraceus was strongest with α‐terpineol. The best inhibitory efficacy against A. ochraceus in grapes also occurred with α‐terpineol. 3‐Carene showed little inhibitory effect. Conclusions: These results demonstrate that not all components in MAO possess antimicrobial effects, and α‐terpineol is the main contributor of MAO's A. ochraceus inhibition effect. Significance and Impact of the Study: α‐Terpineol may be used as an alternative natural preservative for the postharvest storage of grapes and other fruits. [ABSTRACT FROM AUTHOR]

This work was carried out in Diyala Province, North of Baghdad, Iraq during 2016-2017 to isolation and identification the fungi caused Inflorescence rot on data palm and try to combat the disease by using sodium chloride salt. 32 infected samples were collected from 8 varieties of data palm which has been isolated 60 isolates of fungi belong to 6 genus and species of fungi which were Mauginiella scattae, Fusarum proliferum, Penicillum chrysogenum, Rhizopus spp., Mucor spp. and Aspergillus niger, the number of isolates for each one were (20,12,10,6,6,6) respectively. M. scattae showed highest percentage of frequency and occurrence that (33.33, 65.63) %, while F. proliferum recorded the lowest percentage of frequency and occurrence which were (6.66, 18.75)%. Treatment with the sodium chloride salt gave significant reduction in Inflorescence rot on all data palm varieties. Disease incidence and percentage of Infection, which were 0% in all data palm varieties excepting khistawi variety which recorded (22.22, 33.33)% respectively for while control treatment recorded (100, 100)% respectively for Disease incidence and percentage of Infection. This confirms the possibility of using sodium chloride salt as a substitute for chemical fungicides. [ABSTRACT FROM AUTHOR]

Highlights • Picea abies stumps are more infected by Heterobasidion than stumps of other species. • Stump infection frequency increases throughout the year, peaking in the autumn. • Manual operational stump treatment with urea is effective regardless of the species. • Infections of treated stumps are predicted to increase slightly in the autumn. • Treatment benefits depend on species and raise throughout the year, peaking in autumn. Abstract The destructive forest pathogen Heterobasidion annosum sensu lato (s.l.) may be controlled either by timing logging operations in periods of the year characterised by a low risk of airborne stump infection or by treating stump surfaces immediately after felling. 1616 stumps of four of the most widely-distributed European host tree species, either untreated or manually and operationally treated with urea, were sampled from 29 pure and mixed forest stands of the western Italian Alps and analysed for the presence of the pathogen. The aims of the study were to (i) compare the overall and seasonal frequency of stump infection of different tree species; (ii) assess the efficacy of treatments on different tree species; (iii) explore if the efficacy of treatment is affected by the season of application, and (iv) estimate the benefits resulting from treatments at different time periods. Overall, the frequency of infection of untreated stumps was significantly higher (P < 0.05) in Norway spruce (Picea abies) than in European larch (Larix decidua), silver fir (Abies alba) and Scots pine (Pinus sylvestris). In general, the frequency of stump infection of each tree species increased throughout the year, reaching a maximum in autumn, possibly in relation to the higher availability of airborne inoculum in that season. Manual operational stump treatment with urea reduced the frequency of infected stumps compared to controls both overall and for every tree species, although the reduction was significant only in the overall analysis and in the analysis performed separately for Norway spruce and larch. Binary logistic regression models point to the general efficacy of treatments regardless of the season of application, although the frequency of infection of treated stumps is predicted to increase slightly in autumn. Despite the efficacy of treatments being slightly reduced in autumn, the predicted reduction of stump infection probability due to treatments, hence the benefits provided by treatments, is expected to vary in magnitude depending on the species but to increase similarly according to a roughly sigmoid curve throughout the year, approaching a maximum in autumn. The information provided by this paper may help forest managers to design profitable and/or sustainable tactics to control the disease. [ABSTRACT FROM AUTHOR]

Sarsabz, a high yielding, well adapted and bold-seeded pea variety was evolved by hybridizing two varieties Meteor and Lampo at Vegetable Research Institute, Faisalabad Pakistan. The variety was tested in replicated varietal/ station yield trials and multi-locational trials from 2001 to 2014. Sarsabz gave higher green pod yield (8.52 t/ha) than existing pea varieties i.e. Pea-2009 (7.51 t/ha) and Meteor (6.86 t/ha) and Climax (6.94 t/ha) on average basis. It yielded 13 % more than better check (Pea-2009). The most distinguishing trait of this variety is its greater pod width (2.04 cm) than Pea-2009 (1.87 cm), Meteor (1.59 cm) and Climax (1.61 cm) and more No. of pods per plant. Sarsabz is 27 days earlier in pod bearing than Climax and five days than Pea-2009. It is suitable for early planting (mid of October) as well as for normal planting (Mid of November). Its seed is light green, round and bold and its average 100-fresh seed weight is 67.62 g which is greater than Climax (48.4 g), Pea-2009 (67 g) and Meteor (44.18 g). This variety/line has the ability to tolerate against root rot and powdery mildew diseases of pea crop. The newly approved variety has potential to moderately resist to collar rot disease as compared with all other existing varieties. Studies on organoleptic characteristics showed that Sarsabz is less sweet in taste than Pea-2009, suitable for all types of dishes. This variety was approved by Punjab Seed Council and its seed is available for dissemination. [ABSTRACT FROM AUTHOR]

Heterobasidion parviporum and H. annosum are the most damaging root and butt rot pathogens of conifers in southern Fennoscandia where their distribution and frequency are reasonably well described in literature. However, in the most northern boreal forests of Europe the occurrence and significance of these pathogens is poorly known. In the future global warming may increase root and butt rot damages in the North. In this research the distribution of Heterobasidion spp. in northern Finland was compiled from literature and various available databases and from a field study in two counties of northern Finland, Northern Ostrobothnia and Kainuu. Conifer stumps from 101 regeneration cutting sites were inspected and sample discs from stumps with signs of decay were investigated for the presence of Heterobasidion spp. In all, 11,846 stumps were investigated. Decay was found in 429 Norway spruce stumps and 50 Scots pine stumps. H. parviporum was isolated from five spruce discs, each from a different site. H. annosum was not detected. According to previous records H. annosum has been identified only twice in northern Finland and these locations are over 600 km south of the northernmost Scots pine stands in Fennoscandia. Instead, H. parviporum occurs sporadically in the whole distribution area of Norway spruce in northern Finland. Most probably H. parviporum can be found in overmature dense stands at fertile sites but even there only at low frequencies. In northern Finland butt rot of conifers is caused mainly by other decay fungi than Heterobasidion . Low pH of the organic soil layer is probably a significant factor hampering H. parviporum from spreading in the North. [ABSTRACT FROM AUTHOR]

Heterobasidion butt rot causes considerable losses to forestry in coniferous forests in many parts of Europe including southern Fennoscandia. In northern Fennoscandia, including central and northern Finland, both Heterobasidion annosum and H. parviporum are rare. This study aimed to determine the incidence of butt rot in Scots pine ( Pinus sylvestris L.) and Norway spruce ( Picea abies (L.) Karst.) north of the area commonly infested by Heterobasidion spp. in Finland. The incidence of butt rot in these conifers was investigated in Northern Ostrobothnia and Kainuu using two data sets: stump inspections in 101 regeneration cutting sites and the Finnish National Forest Inventory (NFI) data. According to stump inspections butt rot occurred in 1% of Scots pine trees and 10% of Norway spruce trees. In the most recent NFI data from 2009 to 2011 the incidence of trees with rot in mature managed stands of these two counties was 1% and 5% for Scots pine and Norway spruce, respectively. According to NFI, these values are nearly equal to the average incidence of butt rot in mature pines and spruces of the whole of Finland. Consequently, the low incidence of Heterobasidion butt rot in these parts of Finland does not mean lower occurrence of butt rot. Butt rot incidence varied greatly between sites: 0–24% of Norway spruce stumps in spruce dominated sites and 0–13% of Scots pine stumps in pine dominated sites were infected. High butt rot incidence in Norway spruce was associated with high site fertility, stand age, low organic matter content of soil and low temperature sum of the site. In Scots pine butt rot appeared after stand age exceeded 120 years while decay occurred already in 40–80 years old Norway spruces. High butt rot incidence in Scots pine was associated also with high flow accumulation of the site. Precipitation, plot slope, plot aspect, ditches, stand density and elevation were insignificant variables in models explaining decay incidence. During 1991–2013 butt rot incidence in Scots pine or Norway spruce has not changed in the study area. Similarly, to the more southern areas with high Heterobasidion risk, butt rot control in the North should focus especially on fertile mineral soil sites. [ABSTRACT FROM AUTHOR]

Abstract: Tail and fin rot disease (TFRD) is a big issue in the production of spotted snakehead, Channa punctata Bloch. The aims of the present study were to isolate and identify the bacterial pathogen causing TFRD, to detect histopathological changes in tissues (fin, tail, liver, and kidney), and to ascertain the antibiotic sensitivity pattern of the isolate. Out of six bacterial isolates, only the isolate DJ1990 was found to be the causal candidate of TFRD in C. punctata. Identical histopathological changes were detected in tail, fin, liver, and kidney under light and scanning electron microscope in both collected diseased fish and artificially infected fish. The isolate was identified as Pseudomonas aeruginosa strain DJ1990 (National Center for Biotechnology Information Ace. No. KX709967) based on the biochemical characterization tests and 16S rDNA sequence‐based phylogeny analysis. Artificial challenge test demonstrated that the strain DJ1990 was highly virulent (100% mortality at 48 h of postinjection period at the concentration of 1.5 × 107 CFU/g of body weight) for C. punctata. The isolate exhibited sensitivity to the broad‐spectrum antibiotics but was resistant against aztreonum. To the best of our knowledge, this is the first report of P. aeruginosa as a TFRD‐causing candidate in C. punctata. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) are increasingly used as tools to perform a detailed assessment of post-harvest sites. One of the potential use of UAV photogrammetric data is to obtain tree-stump information that can then be used to support more precise decisions. This study developed and tested a methodology to automatically detect, segment, classify, and measure tree-stumps. Among the potential applications for single stump data, this study assessed the possibility (1) to detect and map root- and butt-rot on the stumps using a machine learning approach, and (2) directly measure or model tree stump diameter from the UAV data. The results revealed that the tree-stumps were detected with an overall accuracy of 68-80%, and once the stump was detected, the presence of root- and butt-rot was detected with an accuracy of 82.1%. Furthermore, the root mean square error of the UAV-derived measurements or model predictions for the stump diameter was 7.5 cm and 6.4 cm, respectively, and with the former systematically under predicting the diameter by 3.3 cm. The results of this study are promising and can lead to the development of more cost-effective and comprehensive UAV post-harvest surveys. [ABSTRACT FROM AUTHOR]

Populus tremuloides Michx. is an iconic tree of the mountains of the western United States. In Utah, it very commonly suffers from white trunk rot caused by Phellinus tremulae (Bondartsev) Bondartsev & P.N.Borisov. The incidence of this disease is affected by tree and site characteristics, but the magnitude of these effects appears to be site-dependent. To minimize harvest wood loss in Utah, we determined the locally important factors that explain the wide variation in the incidence of sporocarps of Phellinus tremulae. To avoid confounding of factors, we utilized a multiple regression approach. We found that while the incidence of Phellinus tremulae sporocarps on quaking aspen was always low at high elevations, it was variable at low elevations. Our logistic regression model indicated that variation in the incidence of sporocarps at low elevations was attributable, in part, to variation in aspect, slope, environmental stress, and tree age and size. Based on these results, we recommend that harvesting at elevations below 2500 m be confined to younger trees or to sites on relatively steep, north-facing slopes. Because of site-dependency, the same general method could be used to establish harvesting criteria in other regions. [ABSTRACT FROM AUTHOR]

Stalk rot diseases are among the most ubiquitous and damaging fungal diseases of sorghum (Sorghum bicolor (L.) Moench) worldwide. Although reports of quantitative yield losses to stalk rots are available, the impact of stalk rot on grain quality attributes is unknown. This study was conducted to test whether stalk rot diseases could affect grain mineral (N. P, K; Ca, Mg, Cu, Fe. Mn, and Zn) and macronutrient (protein, fat, and starch) content, ash content, and physical traits (unit grain weight, hardness, and diameter). A field experiment was conducted in 2013 and 2014 with four sorghum genotypes (two hybrids and two lines). Plants from each genotype were inoculated with four stalk rot pathogens (Fusarium andiyazi, F. proliferation, F. thapsinum, and Macrophomina phaseolina) and mock-inoculated with phosphate-buffered saline (control). Grains collected from infected and control plants were analyzed for macronutrient and ash content using near-infrared reflectance spectroscopy, grain hardness and diameter using the single-kernel characterization system, and mineral content using the Rapid Flow Analyzer (Model RFA-300 for N) and inductively coupled plasma spectrometer (for P, K, Ca, Mg. Cu, Fe, Mn, and Zn). Although stalk rot pathogens significantly reduced unit grain weight, they did not significantly affect grain hardness and diameter and, therefore, may not affect milling quality. Pathogens significantly reduced all macronutrient and most mineral contents across genotypes and environments on a per-unit-grain basis, except N and Mg, which were affected in a genotype- and environment-specific manner, and Fe, which was not significantly affected. Most minerals tested were significantly and negatively correlated with disease severity (lesion length) and total grain weight per panicle. The hybrid tested (Pioneer 84G62) exhibited reduced mineral and macronutritional changes after stalk rot infection, providing insights into the possibility of producing high-yielding, nutritionally stable hybrids under stalk rot disease pressure through dedicated breeding efforts. [ABSTRACT FROM AUTHOR]

Sisal (Agave sisalana Perrine ex Engelm) is cultivated in large areas of the Brazilian semi-arid Northeastern region. This crop allows thousands of people to obtain minimal wages. However, a disease known as bole rot, caused by Aspergillus species, is causing a decline in production. The objective of this study was to investigate the involvement of hydrolytic enzymes (cellulase, cutinase, protease and lipase) and ochratoxin A in an in vitro simulation of the interaction between A. niger Tiegh. and sisal to understand the mechanisms of fungal pathogenicity. Primers for cutinase lipase, protease, ochratoxin A, and elongation factor 1-α (EF), with this last one used as endogenous control were designed and optimized for real time quantitative PCR (qPCR) with the SYBR Green methodology. The genes potentially involved in the pathogenicity of A. niger showed higher expression in medium supplemented with sisal as compared to the minimal medium. The primers reported herein will allow detailed studies of the biological events leading to bole rot disease in sisal. These results represent the first data on genes putatively involved in the pathogenicity of A. niger to sisal. [ABSTRACT FROM AUTHOR]

This research was carried out to assess inhibitory effect of UV-C (0.88 kJ m −2 ) against four isolates of Sclerotinia sclerotiorum , causal agent of carrot rot, in vitro and in vivo . A bank of seven germicidal tubes was used to produce UV-C radiation with peak emission at 254 nm. The carrot roots were subjected to UV-C irradiation for five min. The tubes were located 40 cm above the roots. In order to be exposed to UV radiation on all sides, the carrot roots were rotated five times at the interval of one min. Based on the results, UV radiation was able to significantly increase levels of pathogenesis-related proteins (chitinases, peroxidases, β-1,3-glucanases) as well as polyphenoloxidase, phenylalanine ammonia-lyase and 6-methoxymellein (6-m) in carrot roots. The levels of enzymes and 6-m were found to be higher in the whole treated carrots than half treated carrots in most of treatments. Despite increase of systemic acquired resistance (SAR) related enzymes in half treated carrots, the results of in vivo tests showed that UV-C irradiation can not reduce severity of carrot rot after 15 d. In addition, UV-C radiation for 5 min markedly decreased myceliogenic and carpogenic germination of sclerotia in four isolates. This study showed that UV-C cannot be considered as abiotic inducer of SAR. [ABSTRACT FROM AUTHOR]

Understanding genetic mechanisms controlling inheritance of disease resistance traits is essential in breeding investigations targeting development of resistant genotypes. Using North Carolina design II, 32 F1 hybrids were generated by crossing eight susceptible to four resistant parents and submitted for field evaluation. The analysis of general and specific combining ability ( GCA and SCA) indicated involvement of additive and non-additive gene action controlling inheritance of horizontal resistance to sheath rot of rice. High GCA/ SCA ratio and high heritability estimates revealed additive effects and were more predominant than none additive ones. The level of dominance indicated dominant genes was more important than recessive genes. Estimates of GCA and SCA analysis suggested that crop improvement programmes should be directed towards selection of superior parents or good combiners, emphasizing on GCA. As far as source of resistance is concerned, most promising genotypes were Cyicaro, Yunertian and Yunkeng. The predominance of additive genetic effects together with the relevance of dominant genes suggested possibilities of improving the resistance by introgression of resistance genes through recurrent selection coupled with phenotypic selection. [ABSTRACT FROM AUTHOR]

Trunk diseases are factors that limit sustainability of vineyards worldwide. Botryosphaeria and Eutypa diebacks are caused by several fungi belonging to the Botryosphaeriaceae and Diatrypaceae, respectively, with Diplodia seriata and Eutypa lata being two of the most common species. Previous information indicated that the traditional isolation method used to detect these pathogens from plant samples could underestimate their incidence levels. In the present study, we designed two sets of primers that target the β-tubulin gene and that are amenable for quantitative real-time PCR (qPCR) Sybr-Green assays for the detection and quantification of D. seriata-complex (DseCQF/R) and E. lata (ElQF/R) DNA. The design of a species-specific assay was achieved for E. lata. For D. seriata, a species-specific assay could not be designed. The low interspecific diversity across β-tubulin genes resulted in an assay that could not discriminate D. seriata from some closely related species either not yet reported or presenting a low prevalence on grapevine, such as D. intermedia. We validated our technique on grapevine spur samples naturally and artificially infected with D. seriata and E. lata during the dormant season. Experimental grapevines were located in two counties of northern California where the incidence of both pathogens was previously reported. The qPCR assays revealed that a high frequency of pruning wound infections (65%) was achieved naturally by E. lata, while low infection frequency (less than 5%) was observed using the reisolation method. For D. seriata-complex, low (5%) to no natural infection frequencies were observed by the qPCR and the reisolation method, respectively. These results also provided evidence that our qPCR detection methods were more sensitive to assess the incidence of E. lata and D. seriata-complex in plant samples, than traditional isolation techniques. Benefits of molecular methods for the detection of canker pathogens in the field under natural conditions are discussed. [ABSTRACT FROM AUTHOR]

An extensive study was undertaken to manage the most vigorous, polyphagous pathogen Sclerotium rolfsii causing collar rot disease in Gerbera by utilizing nine commercial fungicides and eight novel Trichoderma spp. Under in vitro conditions, there was 61.11 per cent reduction of pathogen (S. rolfsii) by T. harzianum NVTH2 and T. viride TV1 over control and was followed by T. citrinoviride NVTC1, T. citrinoviride NVTC2 and T. asperellum NVTA1 with per cent inhibition of 55.55, 54.44 and 53.33 respectively. On the other hand, commercial fungicides, tebuconazole 50%+ trifloxystrobin 25%, tebuconazole 250 EC, propioconazole 25% EC, fenamidone 10%+ mancozeb 50%WG and propineb 70WP reduced the growth of S. rolfsii to an extent of 100 per cent inhibition in all the tested concentrations. Combination of most effective Trichoderma spp. and fungicides had resulted in the best treatment T2 against the collar rot pathogen of Gerbera under protected cultivation. [ABSTRACT FROM AUTHOR]

Fruit and vine rot of pointed gourd (Trichosanthes dioica) caused by Phytophthora melonis Katsura is a potential disease that occurs extensively in major pointed gourd growing regions of the country. In order to record the effect of planting systems on the incidence and severity of this disease, a study was conducted under trellis and soil bed system of planting during 2015. The study revealed that crop grown in soil bed system had exhibited the vine and fruit rot to the tune of 34.8 and 39.0 percent, respectively during peak rainy season. In trellis system during the study period, there was no fruit and vine rot incidence, however, leaf blight severity to the tune of 2.8 percent was observed as against 28.8 percent in soil bed system. Only the leaf blight was confined to lower most leaves in trellis system. Disease severity was more in soil bed system in rainy season as against other season. Nearly, 40% mortality was observed in seedlings prepared from cuttings taken from soil bed system. Hence on based this study, it was concluded that pointed gourd crop grown on trellis can potentially reduce the leaf, vine and fruit rot severity especially when cropping period coincides with rainy season. [ABSTRACT FROM AUTHOR]

Soil solarization was reported that effective method to control stem rot disease caused by Sclerotium rolfsii, thereby the aim of this study was to improve soil solarization method by combining of biocontrol and chemical control. The experimental was done in the laboratory, pots, greenhouse and micro plot. The effect of high temperatures (45°C, 50°C and 60°C) on the survival of S. rolfsii sclerotia were conducted in the laboratory. At 45 °C, sclerotia treated for 6 hours showed germination of 36%. However, treated at 50°C and 60°C for 1 hours, the sclerotia could not germinate. The effect of soil solarization on sclerotial survival of S. rolfsii was carried under green-house and small plot conditions. The sclerotia were placed deeply under 2 soil levels of 5 and 10 cm and evaluated weekly on germination rate. After 1 week of soil solarization, sclerotia germinated 7.2% at 5 cm depth and 0% after 2 weeks. At 10 cm depth, sclerotia were could not germinate after 1 week of soil solarization. For small plot experiment of soil solarization, the germinated of sclerotia at 5 cm depth was 0% after 3 weeks of soil solarization while 35.2% germination for non solarization. Integrated control of stem rot using fungicide, biocontrol agents and soil solarization was conducted under green-house condition. The result was clearly that soil solarization alone or in combination with others were effective methods against the disease with disease index 0. Without soil solarization, T. harzianium T9 with carboxin caused low disease index of 0.2. The integrated control of stem rot was also undertaken in small plot (1.5×1.5m) experiment with comparison on disease incident and tuber yield of H. tuberrosus. Using soil solarization in combination with T. harzianium T9 and Glomus clarum was the best method that reduced disease with index of 0.33 and provided high tuber yield of 1.69 kg/m2. [ABSTRACT FROM AUTHOR]

Rhizome rot caused by Pythium spp and Fusarium spp is one of the most devastating diseases of ginger in most of the ginger growing areas of the Nepal. Realizing the context for development of alternative control strategies to reduce dependency on synthetic fungicides, a field experiment on management of rhizome rot disease of ginger using eco-friendly natural products was conducted at GRP, Kapurkot, Salyan during 2012/2013. Fresh and fermented extract of Artemesia vulgaris Linn (Titepati), Urtica dioica (Sisnoo), Zanthoxylum armatum DC. (Timbur), Allium cepa L., (Onion), Allium sativum L. (Garlic), Capsicum annuum L. (Chili), Nicotiana tabacum (Tobacoo) along with Jeevatu (a mixed product of beneficial microbes) and biofit were tested in the experiment. Experiment was conducted in the naturally inoculated sick plot in RCB design with eight treatments replicated thrice. Each experimental plot area was 3m x1.5m (4.5m²). Observation on plant number, tiller clump-1, plant height, disease incidence, fresh rhizome yield, disease rhizome yield and mother rhizome yield were recorded and evaluated using statistical analysis tool MSTAT-C. Fresh rhizome yield for all the treatments were found lower than national average. Jeevatu (5%) treated plot had highest fresh rhizome yield (7.70 m t ha ¹) followed by (onion+garlic+chili) + urine (1:3) fermented extract (4.88 mt ha ¹). Similarly, rhizome rot scale (1.66), disease incidence (41.96%) and the diseased rhizome yield (0.74 mt ha ¹) was shown least on jeevatu treated plot. Highest disease rhizome yield (2.37 mt ha ¹) was obtained in the treatment titepati + urine (1:2) fermented extract followed by control (2.07 mt ha ¹). [ABSTRACT FROM AUTHOR]