Leaf Blister Research Articles

Phenotypic characterization and genetic analysis for identification of trait-specific germplasm in Sunflower (Helianthus annuus L.)

An experiment conducted at TNAU, Coimbatore, during the rabi season of 2023-2024, evaluated 105 sunflower germplasm lines using ARBD. The ANOVA indicated significant differences among twelve traits, with high genetic variability observed in oil yield per plant, seed yield per plant, and hundred seed weight. Heritability and genetic advance were notably high for plant height, seed yield per plant, and oil yield per plant. Correlation analysis showed that seed yield per plant was positively correlated with plant height, head diameter, hundred seed weight, oil content, and oil yield per plant but negatively with leaf size. Path analysis revealed that oil yield per plant had the most substantial positive direct effect on seed yield, while oil content had the most significant negative direct effect. Plant height, head diameter, and hundred seed weight positively influenced yield indirectly through oil yield per plant but negatively via oil content. Principal Component Analysis (PCA) identified four principal components with Eigen values greater than 1, explaining 62.91 % of the variability. Notably, diverse genotypes included CB-GMU1189, CB-GMU-400, and CB-IB-62. Mahalanobis D2 statistics identified seven clusters, with Cluster 1 containing the most genotypes and Clusters 6 and 7 showing the highest inter-cluster distance, indicating significant genetic diversity. Cluster 5 had the highest mean for several traits. The sunflower germplasm accessions exhibited considerable variability in morphological characteristics such as hypocotyl pigmentation, leaf blistering, leaf serration, petiole pigmentation, stem pigmentation, ray floret shape, stigma pigmentation, seed shape, seed stripes, and seed stripe colour. Therefore, the accessions identified for superior traits include 14 genotypes for very high yield (>35 g/plant), five for high seed oil content (40-43 %), and 22 for high 100-seed weight (>6 g) and can be considered as superior trait-specific accessions in sunflower.

First record of Leucoptera malifoliella (O. Costa, 1836) (Lepidoptera: Lyonetiidae) in Tunisia

AbstractThe leaf blister moth, Leucoptera malifoliella is an invasive pest of apple and other Rosaceae species. It causes significant damage to apple leaves, threatening the production quality and the overall health of the tree. In this paper, we report the first record of L. malifoliella in Tunisia and give details of its distribution in apple orchards of central west Tunisia (Kasserine governorate). After signs of the pest were observed, cocoons were collected from the field and reared until adult eclosion. Identification of the species was based on observations of external morphology in the laboratory in addition to the field diagnosis based on larval damage on leaves. Leucoptera malifoliella was collected firstly in Foussana delegation, then in Sbeitla, Sbiba, Djedliane, Kasserine and Feriana delegations, showing that it is widely spread in the Kasserine governorate. This leaf miner was clearly identified as one of the most abundant pests in some localities. This paper describing the first record of L. malifoliella in central west Tunisia aims to raise awareness on the pest and encourage the collaboration between apple producers, researchers and extension services in the region to establish a programme of monitoring and managing the pest.

Classification of Clove Leaf Blister Blight Disease Severity Using Pre-trained Model VGG16, InceptionV3, and ResNet

Clove is one of the precious plants produced in Indonesia. Clove has many benefits for humans, but clove cultivation often experiences problems due to disease attacks, including Leaf Blister Blight Disease(CDC). The handling of CDC disease is carried out based on the severity of the symptoms that can be seen on the affected leaves. This research was conducted to obtain a CDC disease classification model, so appropriate treatment can be carried out. This study used the pre-trained VGG16, InceptionV3, and ResNet models for classification. VGG16 got the highest average accuracy of 96.7%. Aside from that, k-fold cross validation improved the model's accuracy.

First report of Exobasidium miyabei causing Exobasidium leaf blisters on Rhododendron mucronulatum in Korea

AbstractRecently, a previously unseen Exobasidium leaf blister disease was observed on Rhododendron mucronulatum in its natural habitat in Korea. The fungus associated with the disease was identified as Exobasidium miyabei based on morphological characteristics and two‐locus sequence analyses. To our knowledge, this is the first report of E. miyabei in Korea and of its novel association with the host species, R. mucronulatum.

Ecological and biological features of the selected forms of checker tree for successful targeted introduction and reintroduction into the ecological network of Ukraine

The study considers the issues of introduction and reintroduction of the Red Book species of checker tree in the system of decorative gardening, forest protection, and forest ecosystems. That is why the purpose of the study was to monitor the green corridors of rural and urban ecosystems of the forest-steppe zone of Ukraine, to investigate and select the best forms of checker tree in terms of morphological characteristics and physiological properties for promising areas of distribution and conservation in the form of pure and mixed plantings. The following methods were used in the research: route, field, biometric, laboratory, comparative analysis, mathematical and statistical. New forms of checker tree were introduced, studied in in situ and ex situ conditions, and selected for the prospects of their further introduction and reintroduction into the ecological network of Ukraine and conservation to activate trophic, phoric, and other types of biotic interactions in a single territorial ecosystem. Sparsely distributed biotypes of Torminalis glaberrima (Gand.) Sennikov & Kurtto f. Intermedia Kossetz were found in the zone of green corridors of rural and urban ecosystems of the forest-steppe zone of Ukraine. Some specimens of these biotypes were identified as valuable material for introduction into the system of fruit and ornamental gardening, including parks and monuments of landscape art, as well as natural monuments, protected tracts, sanctuaries and reserves of pure and mixed plantings, alleys, forest reclamation strips, etc. It was established that the elements of originality of the selected forms of checker tree – Eva, Podolianochka and Slavka – are the specificity of the crown shape, which determines the level of productivity, small and medium growth force, normal reaction to pruning (which affects the size and yield of fruits), high degree of flowering (60-80%), increased fruit size (diameter of more than 2 cm), increased fruit weight (1.8-2.1 g), increased number of fruits on the stem (≥20 units), a pleasant and harmonious taste of fruits, high quality of fruits, lack of periodicity in fruiting in nature and in culture, high xenogamy (69-75%), high yield of fruits from the plant, increased winter hardiness (7.5 pt.), high drought resistance (8 pt.) and resistance to pests, including pear leaf blister mite (7-9 pt.). The findings can be used in the future to replenish pure and mixed plantings in the ecological network of Ukraine

Monitoring System for Leucoptera malifoliella (O. Costa, 1836) and Its Damage Based on Artificial Neural Networks

The pear leaf blister moth is a significant pest in apple orchards. It causes damage to apple leaves by forming circular mines. Its control depends on monitoring two events: the flight of the first generation and the development of mines up to 2 mm in size. Therefore, the aim of this study was to develop two models using artificial neural networks (ANNs) and two monitoring devices with cameras for the early detection of L. malifoliella (Pest Monitoring Device) and its mines on apple leaves (Vegetation Monitoring Device). To train the ANNs, 400 photos were collected and processed. There were 4700 annotations of L. malifoliella and 1880 annotations of mines. The results were processed using a confusion matrix. The accuracy of the model for the Pest Monitoring Device (camera in trap) was more than 98%, while the accuracy of the model for the Vegetation Monitoring Device (camera for damage) was more than 94%, all other parameters of the model were also satisfactory. The use of this comprehensive system allows reliable monitoring of pests and their damage in real-time, leading to targeted pest control, reduction in pesticide residues, and a lower ecological footprint. Furthermore, it could be adopted for monitoring other Lepidopteran pests in crop production.

‘Candidatus Phytoplasma solani’ (Subgroup 16SrXII-A) Associated with Nicotiana tabacum Leaf Abnormality in Turkey

Tobacco (Nicotiana tabacum) is among the agricultural products with the highest added value in Turkey. Although frequently associated with its negative effects on human health, it also provides important contributions to the Turkish economy with the employment it creates in rural areas and continues to be a strategic product. Many postgraduate theses and studies related to the sociological and economic importance of the production of this plant, which is of great importance for our country, have been carried out. However, there are very limited studies on plant diseases in tobacco production areas in Turkey. Phytoplasma is one of the important plant pathogens that cause yield loss in tobacco. Since available data on phytoplasma diseases on tobacco was very scarce worldwide, field surveys to collect samples showing phytoplasma infection-like symptoms such as yellowish color changes, leaf blisters, proliferation, dwarfism, and other physical abnormalities were carried out in Çanakkale and Balıkesir provinces of Turkey from June to August 2021. The presence of phytoplasmas in six samples was confirmed by 16S ribosomal DNA amplification by nested-PCR using universal phytoplasma primer sets, which also suggested the pathogen associated with the symptoms on tobacco. According to phylogenetic study and virtual-RFLP analysis using AluI and MseI endonuclease enzymes, the six Turkish tobacco phytoplasma strains all belong to group 16SrXII and have more than 99% nucleotide sequence identity with some members of ‘Candidatus Phytoplasma solani’ of the taxonomic subgroup ‘stolbur’ (16SrXII-A). Genetic distances analysis indicated that group 16SrI was more closely related to 16SrXII than 16SrVI, in agreement with the groups clustering in the phylogenetic tree. Neutrality tests found that 16SrI and 16SrXII groups are experiencing expanding or bottleneck selections, probably due to new mutations in the 16S rRNA gene fragment. Meanwhile, 16SrVI populations are shown to be undergoing balancing selections, indicating that its isolates have evolved for a long time.

Leaf blister on two Ericaceae plants infected by Exobasidium species in Japan

AbstractWhitish blisters covered by a hymenium layer were found on the leaves of two Ericaceae plants, Vaccinium japonicum and Rhododendron lagopus var. niphophilum, in Shiramine, Ishikawa, Japan. Based on the morphological characteristics and molecular phylogenetic analyses, the pathogens found in V. japonicum and R. lagopus var. niphophilum were identified as Exobasidium rostrupii and Exobasidium yoshinagae, respectively. This is the first report of E. rostrupii and Exobasidium leaf blisters in two plants in Japan.

Pearleaf Blister Mite (Eriophyes pyri Pgst.): Biological Features and Measures to Limit its Harmfulness in Pear Plantations of Ukraine

Goal. To clarify the biological features of pearleaf blister mite (Eriophyes pyri Pgst.) and investigate the effectiveness of such preparations as: Sivanto Prime 200 SL, PK (flupyradifurone, 200 g/l), Danadim stable, KE (dimethoate, 400 g/l), Oberon Rapid 240 SC, KS (spiromesifen, 228.6 g/l + abamectin, 11.4 g/l), Fufanon 570, KE (malathion, 570 g/l) and Aktofit, KE (aversectin C, 0.2%), reduce the number and harmfulness of this phytophagan, its impact on the productivity of pears in industrial plantations.
 Methods. To determine the colonization of pear plantations by mites in horticultural farms of Ukraine, route surveys were carried out in the industrial pear plantations of Yablunivska variety. The planting scheme was 0.8 × 3.5 m. The planting year was 2014. The crown shape was thinned (improved) and story. The rootstock was a quince tree A. Stages of plant development at the time of treatment were «bursting buds (green cone)» (BBCH 10), «white buds» (BBCH 55), «end of flowering» (BBCH 69) and «fruit development» BBCH 75). The technical effectiveness of pesticides at different application rates was determined. The accounts were performed according to generally accepted methods in horticulture, plant protection and entomology.
 Results. Female pear leaf blister mite overwinter under the upper scales of the buds. In spring, at an average daily temperature above 10°C, they begin to feed with the juice of young leaves, covering them with galls, and lay eggs («bud bursting (green cone)» — «white bud») stages. The development of the first generation ends at the end of «flowering». Females of the second generation appear in late June, the third generation — in the first half of July. After rebirth, they leave galls and populate the buds for wintering (mid-late June to late Julyearly August). During the growing season the phytophagan develops in three generations. The use of Danadim stable, KE, Fufanon 570, KE, Sivanto Prime 200 SL, PK, Oberon Rapid 240 SC and Aktofit, KE provided a reduction in the number of this species by 75.3—93.9%, allowed to increase the effectiveness of basic biometric and biochemical indices of plantations, to obtain high-quality products with a yield of 1.1—1.5 times higher comparing with the control.
 Conclusions. During the growing season, the pear gall mite develops in three generations. Taking into account the peculiarities of the biology of pears and mites in the spring, the peculiarities of the mechanism of action of drugs against this species and other phytophages (leafeating, stem, sucking, including against the brown-marble bug) are most advisable to apply: in the phase of «bud break (green cone)» — Danadim stable, EC (2.0 l/ ha); in the «white bud» phase — Fufanon 570, EC (2.0 l/ha); after the «end of flowering» — Danadim stable, EC (2.0 l/ha). In summer (against the second and third generations of the pest), Sivanto Prime 200 SL, RK (0.75—1.0 l/ha), Oberon Rapid 240 SC, KS (0.6—0.8 l/ha), Aktofit, EC (6.0 l/ha) taking into account the duration of their action.

Two new species and complementary descriptions of four new records of family Eriophyidae (Acari: Trombidiformes) in Egypt

During a survey on eriophyoid mites associated with plants in Egypt, six eriophyoid species were collected. The genus Neserella Meyer & Ueckermann, 1989 is reported for the first time from Egypt based on newly collected samples of N. capreifoliae Meyer & Ueckermann, 1989 vagrant on leaves of Ficus carica L. (Moraceae). Aceria sissoae sp. nov. collected from Dalbergia sissoo DC. (Leguminosae) vagrant on the undersurface of petals and pods causing rusting symptoms. Three new records, Aceria suri Ueckermann, 1991 on leaves and buds of Ficus sycomorus L. (Moraceae) causing leaf blisters, Aceria tribuli (Keifer, 1974) vagrant on the stems and leaves of Tribulus terrestris L. (Zygophyllaceae), Aceria tumisetus Meyer & Ueckermann, 1992 vagrant on the upper side of the leaves of Gazania ringens (L.) Gaertn. (Compositae) are collected for the first time in Egypt. Also, a new species, Tegonotus caricus sp. nov., was found on F. carica L. and herein described and illustrated. This is also the first record for the genus from Egypt. Complementary descriptions and illustrations of the four newly recorded species based on adult females, males and immature stages are also included. A key to eriophyoid mite species associated with family Moraceae in Egypt is provided.

Changes in the Field of Library and Information Science from Ancient Time to the Present Time: A Study

If we throw light on the history of the libraries in India, and then one main fact comes to light that the history of the libraries in India is a thousand of years old. The development of libraries in India can be divided in to Ancient Period, Middle Period, Mughal Period and Modern Period. Libraries existed those days when education was concentrated in Gurukul. Those days Guru was like a moving Library and they had unlimited store of knowledge. Over time, writing and ink began to be used and texts were also produced. In ancient times, handwritten texts were wrapped in cloth and leaf blisters because the art of printing was not invented at that time, But with the time the art of printing was invented and texts started to be printed and libraries came in to existence. The demolition of ancient cities which have been obtained by excavation is a proof that libraries existed in ancient times as well. Nalanda University established in ancient time had a three story Library Building called Ratnodadhi, Ratnasagar and Ratnaranjak. Similarly, temples and monasteries also had their own libraries which used to support religious and educational institutions. Father of Library Science Dr. S.R.Ranganathan who was presented the five laws of Library Science, his untiring efforts resulted in unlimited growth/development in the field of Library Science and the Library received a new direction and helped to give scientific form to the Library Service.

Applying deep neural networks to predict incidence and phenology of plant pests and diseases

AbstractA major challenge of agriculture is to improve the sustainability of food production systems in order to provide enough food for a growing human population. Pests and pathogens cause vast yield losses, while crop protection practices raise environmental and human health concerns. Decision support systems provide detailed information on optimal timing and necessity of crop protection interventions, but are often based on phenology models that are time‐, cost‐, and labor‐intensive in development. Here, we aim to develop a data‐driven approach for pest damage forecasting, relying on big data and deep learning algorithms. We present a framework for the development of deep neural networks for pest and pathogen damage classification and show their potential for predicting the phenology of damages. As a case study, we investigate the phenology of the pear leaf blister moth (Leucoptera malifoliella, Costa). We employ a set of 52,322 pictures taken during a period of 19 weeks and establish deep neural networks to categorize the images into six main damage classes. Classification tools achieved good performance scores overall, with differences between the classes indicating that the performance of deep neural networks depends on the similarity to other damages and the number of training images. The reconstructed damage phenology of the pear leaf blister moth matches mine counts in the field. We further develop statistical models to reconstruct the phenology of damages with meteorological data and find good agreement with degree‐day models. Hence, our study indicates a yet underexploited potential for data‐driven approaches to enhance the versatility and cost efficiency of plant pest and disease forecasting.

Key Plant, Key Pests: Oak (Quercus spp.)

This series of Key Plant, Key Pests publications is designed for Florida gardeners, horticulturalists, and landscape professionals to help identify common pests associated with common Florida flora. This new 9-page publication provides information and general management recommendations for borers, caterpillars, insect-induced galls, twig girdlers, oak leaf blister, root and butt rot, Tubakia leaf spot, mistletoe, psocids, lace bugs, woolly aphids, powdery mildew, Spanish and ball moss, and lichens. Written by Juanita Popenoe, Caroline R. Warwick, Adam G. Dale, and Alfred Huo, and published by the UF/IFAS Environmental Horticulture Department.https://edis.ifas.ufl.edu/ep596

Grape erineum mite: Postharvest sulfur use reduces subsequent leaf blistering

The occurrence of eriophyid mites (Calepitrimerus vitis [rust mites] and Colomerus vitis [erineum mites and bud mites]) in vineyards worldwide is associated with leaf deformation, stunted shoot growth and reduced yield potential. In the North Coast region of California, leaf blistering by the erineum strain of Colomerus vitis is the most widespread symptom of eriophyid mite damage. Unlike rust and bud mites, erineum mites are generally considered a nuisance pest that is incidentally controlled by sulfur-dominated management programs for powdery mildew. However, recent reductions in the use of sulfur have allowed erineum mite populations to expand, highlighting the need for alternative management options. In this study, we posited that, during autumn, mites moving to buds from erinea (leaf blisters) to overwinter could be susceptible to sulfur applications. During four growing seasons, we documented patterns of mite movement to identify key sulfur application timing. We found the greatest numbers of migrating erineum mites from late September to early November. Concurrently, in replicated trials, we evaluated the efficacy of postharvest sulfur applications to reduce blistering. Sulfur applied during the migration period in 2013 appeared to eradicate leaf blistering in the 2014 growing season. In subsequent trials, sulfur treatments reduced blistering to less than 10% incidence, compared to 40% to 50% incidence in control plots.

Cambios ultraestructurales en blastosporas de Taphrina caerulescens en presencia de hospedante susceptible y no susceptible

<em>Taphrina caerulescens</em> es un hongo fitopatógeno de encinos, que causa ampollas en hojas de 50 especies de <em>Quercus</em>. En 2015, el hongo se aisló por primera vez de <em>Quercus eduardii</em>, especie de encino endémica de la Sierra Fría de Aguascalientes, México. El objetivo de este estudio fue documentar los cambios que se producen en el inóculo fúngico antes de la infección de su hospedante a medida que cambia de saprófito a parásito. Se utilizaron dos especies de plantas hospedantes: <em>Q. eduardii</em> y <em>Q. potosina</em>, y una especie no hospedante, <em>Pittosporum tobira</em>. En el microscopio electrónico de barrido se analizaron muestras de hojas 24 h, 48 h y 72 h post inoculación con una suspensión de conidios de <em>T. caerulescens</em>. Se observó una gemación moderada de conidios después de 24 h en muestras de <em>Quercus</em>; después de 48 h la gemación incrementó en las dos especies de <em>Quercus</em> y se observó la formación de blastosporas significativamente más pequeñas, que el inóculo original en las muestras de <em>Quercus eduardii</em>. La formación de tubos germinativos de las blastosporas pequeñas se comprobó después de 48 h en <em>Quercus</em> <em>eduardii</em>. Los tubos germinativos se observaron creciendo de manera aleatoria hacia las estomas. No se observaron cambios significativos en las muestras no hospedantes. No existe otro reporte de blastosporas pequeñas en <em>T. caerulescens</em>.

Quantitative Trait Loci (QTLs) for Intumescence Severity in Eucalyptus globulus and Validation of QTL Detection Based on Phenotyping Using Open-Pollinated Families of a Mapping Population.

Intumescence is a nonpathogenic physiological disorder characterized by leaf blistering. This disorder can affect growth and development in glasshouses and growth chambers and may be confused with pathogenic diseases. We used quantitative trait loci (QTL) analysis to examine the genetic basis of variation in intumescence severity in Eucalyptus globulus, and test for colocation with previously detected QTLs for pathogen susceptibility. QTL analysis used the phenotype means of open-pollinated (OP) families of an outcrossed F2 mapping family (OP F3; n = 300) of E. globulus and the linkage map constructed in the F2. We validate this phenotyping approach for QTL analysis by assessing a trait previously used for QTL discovery in the F2 and showing the same major QTL was detected with the OP F3. For intumescence severity, five putative QTLs were detected across four linkage groups. Four of these did not colocate with previously reported QTLs for fungal pathogen susceptibility in Eucalyptus, suggesting the mechanisms underlying susceptibility to intumescence and to the two fungal pathogens are largely independent. This study demonstrates there is a genetic basis for variation in intumescence severity, reports the first QTL for intumescence severity in plants, and provides a robust framework for investigating the potential mechanisms involved.

A new species of Neopronematus and a re-description of Pronematus rykei Meyer & Rodrigues (Acari: Iolinidae) from Iran.

Neopronematus iranensis sp. nov. is described and illustrated and the female and male of Pronematus rykei (Meyer & Rodrigues, 1966) are re-described and reported for the first time from Iran. These species were collected from walnut leaves infested by leaf blister mite, Aceria tristriatus, (Nalepa, 1890), in Hamedan and Lorestan provinces, Iran. Furthermore, a key to all known species of Neopronematus is provided.

Genetic variation in resistance to leaf fungus indirectly affects spider density.

Many host-plants exhibit genetic variation in resistance to pathogens; however, little is known about the extent to which genetic variation in pathogen resistance influences other members of the host-plant community, especially arthropods at higher trophic levels. We addressed this knowledge gap by using a common garden experiment to examine whether genotypes of Populus trichocarpa varied in resistance to a leaf-blistering pathogen, Taphrina sp., and in the density of web-building spiders, the dominant group of predatory arthropods. In addition, we examined whether variation in spider density was explained by variation in the density and size of leaf blisters caused by Taphrina. We found that P.trichocarpa genotypes exhibited strong differences in their resistance to Taphrina and that P.trichocarpa genotypes that were more susceptible to Taphrina supported more web-building spiders, the dominant group of predatory arthropods. We suspect that this result is caused by blisters increasing the availability of suitable habitat for predators, and not due to variation in herbivores because including herbivore density as a covariate did not affect our models. Our study highlights a novel pathway by which genetic variation in pathogen resistance may affect higher trophic levels in arthropod communities.

Leaf Blister Mites (Eriophyes sp.) as Significant Pests in Orchards

Leaf Blister Mites (Eriophyes sp.) as Significant Pests in Orchards

Phenotypic diversity of soybean (Glycine max (L.) Merr.)accessions in the Philippines for utilization

An increasing trend of soybean production and consumption has been seen in the Philippines. To assess the potential of the soybean germplasm for utilization, diversity of the Philippine soybean collection was established. High diversity was marked on 17 out of 29 qualitative characters, which include plant growth habit, leaf blistering and flower standard color. Phenotypic diversity indices (H’) of 92 soybean accessions averaged at 0.62. This aside, traits identical to a variety of soybean with superior characters were all present in the soybean germplasm collection. Using simple matching similarity coefficient, cluster analysis separated the different accessions into 12 distinct clusters at 62% similarity. Categorical Principal Component Analysis (CATPCA) showed that two independent components accounted for 35.36% of the total variation of the qualitative morphological characters. Factor loadings for each component showed the morphological characters, such as pubescence color, flower wing color, and seed coat color, that were contributing to the high projections in the two principal components. Accessions with vigorous seedlings were also observed. With the marked trait diversity, the soybean collection could be potentially used directly and for breeding purposes. Consequently, to uncover further the potential of our genetic resources at hand, the remaining germplasm accessions at NPGRL should be characterized and evaluated