Fruit Rot Disease Research Articles

First report of fruit rot disease agent, Colletotrichum fioriniae, on Olea europea cv. Gemlik in Turkey

First report of fruit rot disease agent, Colletotrichum fioriniae, on Olea europea cv. Gemlik in Turkey

Development of rapid, efficient and cost effective screening technique for testing arecanut against Phytophthora meadii incitant of fruit rot disease

To accelerate identification of disease resistant arecanut germplasm or hybrids against Phytophthora, it is very much imperative to develop bioassays which could differentiate resistant and susceptible cultivars efficiently. Here, developed a cost effective and rapid technique called “Detached Leaf Assay” to identify resistant germplasm at the seedling stage itself. Standardized zoospore production in highly virulent Phytophthora meadii (P19) by incubating under 12 hours light and dark regime. Zoospore suspension adjusted to 105spores ml-1 in petri plates. Subsequently, surface sterilized arecanut leaves were floated in zoospore suspension and incubated at temperature of 24±1°C. Disease symptoms, including water-soaked lesions, were recorded three days after inoculation. Infection lesion increased from 1 to 7.3 cm2. The pathogen was re-isolated and confirmed with the original culture. The assay was successfully validated to screen arecanut accessions, wild types and hybrids against P. meadii. This technique is the first to be developed, and it is simple, cost-effective, and faster. It also provides consistent infection and could be effectively utilized to screen arecanut germplasm or hybrids against P. meadii in the seedling stage itself.• Developed a cost effective, efficient and rapid screening technique• The technique was validated to identify resistant genotypes against Phytophthora meadii at the seedling stage.

Isolation, identification and multi-locus sequence typing of Phytophthora capsici from capsicum fields and its cross-infectivity in different crop species

Phytophthora capsici is a major soil-borne oomycete plant pathogen, which severely affects the productivity of peppers including Capsicum annuum L., by causing fruit rot, root rot, and foliar blight diseases. It has a broad host range beyond Capsicum species and evolves rapidly to find new potential hosts for survival under different climatic conditions. In the present study, P. capsici was isolated from soil using castor seed baiting, and characterized through growth patterns and spore morphology. The species identification and molecular characterization were achieved through multi-locus sequence and phylogenetic analysis of three genomic loci (ITS, tef1 and cox), and also attributed given P. capsici isolate Pc_UHF into India-specific ITS-based evolutionary lineage Pc-X. Interestingly, dN/dS estimates revealed reasonably high positive selection in the tef1 gene, which could have possible implications on the pathogen's adaptation and/or virulence. Pathogenicity of this isolate was tested in three commercially growing bell pepper varieties and also in other crop species using detached leaf and/or in planta disease screening. Differential disease symptoms were induced by Pc_UHF in three bell pepper varieties, such as both collar rot and foliar blight symptoms observed in "Yolo Wonder" and "California Wonder", whereas only foliar blight symptoms were recorded in "Solan Bharpur". Furthermore, cross-pathogenicity was also recorded in tomato, citrus, cucumber and eggplant. This is the first report of molecular characterization and cross-pathogenically assessment of P. capsici isolate from farm soils in the North Western Himalayan region of India, which has a dynamic virulence profile and distinct host range.

Association of meteorological variables with leaf spot and fruit rot disease incidence in eggplant and YOLOv8-based disease classification

Eggplant is one of the major vegetables consumed worldwide. Several fungal, bacterial, and viral diseases challenge the yield and quality of eggplant. The incidence of plant diseases is strongly influenced by weather factors such as temperature, humidity, rainfall, and wind speed. Mattu Gulla (MG) is a GI-tagged traditional variety of eggplant grown in Mattu village of the Udupi district in Karnataka state, India, with a cultural legacy of more than four centuries. In this study, we investigated the relationships between weather parameters and disease incidence in Mattu Gulla. Leaf spot (LS) and fruit rot (FR) are the major diseases affecting this plant variety. The influence of plant age and weather parameters on the modulation of the disease incidence (%) [DI (%)] of leaf spot and fruit rot was recorded and analyzed via correlation and regression. Prediction equations for disease incidence was derived via regression. A significant negative correlation was observed between the leaf spot DI (%) and minimum temperature (Min. temp), and a positive correlation was observed between the DI (%) and fruit rot. In the case of FR, the DI (%) is also significantly positively correlated with wind speed (WS), temperature, maximum relative humidity (RH I), rainfall (RF), and wind speed (WS). An RH I of 86–87 % was favorable for the incidence of fruit rot in the field. Regression analysis revealed a significant association between Min. temp and leaf spot DI (%), and in the case of fruit rot DI (%), the association was with Min. temp and WS. An android application, “Leaf Guard,” has been developed for AI-based disease detection in eggplant. During testing, the accuracy of the trained model reached 98.2 %.

Growth Response of Cocoa Seedlings (Theobroma cacao L.) in several Combinations of Planting Media and Trichoderma sp. as Biological Fertilizer

Indonesia is the third largest cocoa (Theobroma cacao L.) producing country in the world. In 2019 cocoa production in Lampung was 58,852 tons with a plantation area of 79,356 ha, in 2020 it was 58,623 tons with an area of 79,469 ha and in 2021 58,414 tons with an area of 77,174 ha. One of the reasons for this decline in production is plant pest organisms (OPT), namely fruit rot disease caused by the pathogen Pytophthora palmivora. Use of Trichoderma sp. can increase plant resistance and growth and act as a biological controller outside and inside the soil. The research was carried out on the grounds of the Lampung State Polytechnic from August to November 2023. This research aims to determine the effect of planting media and administration of Trichoderma sp. on the growth of cocoa seedlings. The method used was a Randomized Block Design (RAK) with 4 treatments and 4 replications so that there were 16 experimental units. Treatment P0 consisted of: Top Soil (Control), P1 Top Soil + Compost Fertilizer (2:1), P2 Top Soil + Trichoderma sp. (50:1), P3 Top Soil + Compost + Trichoderma sp. (50:25:1). The results of the research on treatments P3, P2 and P1 affected plant height, number of leaves and stem diameter. The P3 treatment showed the best results for the variables plant height 39.50 cm, number of leaves 21.58 and leaf area 37.79 cm2. Treatment P2 showed the best results for the stem diameter variable of 0.66 cm.

Managing fruit rot diseases of Vaccinium corymbosum.

Blueberry is an important perennial fruit crop with expanding consumption and production worldwide. Consumer demand for blueberries has grown due to the desirable flavor and numerous health benefits, and fresh market production in the U.S. has risen in turn. U.S. imports have also increased to satisfy year-round consumer demand for fresh blueberries. Pre- and post-harvest fruit diseases such as anthracnose (caused by Colletotrichum spp.) and botrytis fruit rot (caused by Botrytis spp.) have a significant impact on fruit quality and consumer acceptance. These are also among the most difficult diseases to control in the blueberry cropping system. These latent pathogens can cause significant losses both in the field, and especially during transport and marketplace storage. Although both diseases result in rotted fruit, the biology and infection strategies of the causal pathogens are very different, and the management strategies differ. Innovations for management, such as improved molecular detection assays for fungicide resistance, postharvest imaging, breeding resistant cultivars, and biopesticides have been developed for improved fruit quality. Development and integration of new strategies is critical for the long-term success of the blueberry industry.

Identification pests and diseases of coffee plant on Mount Puntang as a basis for integrated pest management to support sustainable development goals

One of the main advantages in plantation exports in Indonesia is coffee plants, but it should be known that there are many types of pests associated with coffee planting. identifying pests and diseases is the basis for reducing possible crop losses. This research aims to control the growth of pest populations. This research uses a descriptive approach by directly following up in the field by making direct observations in sampling the data to be obtained. Performed by identifying the types of pests and diseases found in coffee plants in Gunung Puntang Bandung by making Belt Transect and performing 2 sampling techniques: hand sorting and beating tray. The overall pest species that were sampled in 3 sampling times in the Gunung Puntang Bandung coffee plantation consisted of 6 orders, and 27 pest species that attacked coffee plants. There are 5 types of damage caused by pests found in Gunung Puntang Coffee Plantation, namely leaf miner perforated leaves by Spodoptera litura and chrysomelidae, fruit rot and Green Coffee Scale Disease. There are five diseases identified, namely Cercospora leaf spot rust, Powdery mildew, Antarnoxa, and Coffee Berry Desease. The thing that affects the number of pests and diseases in Gunung Puntang coffee plantations is the climate and environmental conditions that are adequate for these pests to develop and grow.

First Report of Fruit Rot Disease on melon (Cucumis melo L.) Caused by Fusarium ipomoeae in China.

Fusarium rot on melon fruit has become an important postharvest disease for producers worldwide, typically involving multiple Fusarium pathogens (Khuna et al. 2022; Medeiros Araújo et al. 2021). In 2022, Fusarium fruit rot of muskmelon (Cucumis melo var. conomon) occurred sporadically in a field at Huainan Academy of Agricultural Sciences (32.658193º N, 117.064922º E) with an incidence of about 10%. Among these diseased muskmelons, a fruit exhibiting a white to yellowish colony athe intersection of the diseased and healthy tissues was collected and labeled TGGF22-17. The streak plate method was employed to isolate fungal spores on Bengal Red PDA (potato dextrose agar), which were then incubated at 25℃ in darkness. Following isolation and purification, a single-spore strain, TGGF22-17, was obtained and analyzed using morphological characters on PDA, synthetic nutrient agar (SNA) and carnation leaf agar (CLA) (Leslie and Summerell 2006), along with molecular identification. Colours were rated according to the color charts of Kornerup and Wanscher (1978). Based on the colony morphology on PDA, the isolate displayed a rosy buff or buff color with a white to buff margin. The colony margin was undulate, with the reverse transitioning from amber-yellow to honey-yellow. Aerial macroconidia on SNA were thin-walled, hyaline, mostly 3-5 septate, falcate, and measured 18.5-46.4 (x̄=34.2) × 2.9-4.8 (x̄ =3.9) μm in size (n =50). Sporodochial macroconidia on CLA were mostly five-septate with long apical and basal cells, exhibiting dorsiventral curvature. They were hyaline, with the apical cell hooked to tapering and the basal cell foot-shaped, measuring 46.5-89.6 (x̄ =72.3) × 3.5-5.0 (x̄ =4.3) μm in size (n = 100). Portions of three loci (TEF-1α, RPB1 and RPB2) were amplified and sequenced as described by Wang et al. (2019). Sequences were deposited in GenBank with accession number PP196583 to PP196585. The three gene sequences (TEF-1α, RPB1 and RPB2) of strain TGGF2022-17 shared 99.5% (629/632bp), 97.9% (1508/1540 bp) and 99.9% (1608/1609 bp) identity to the ex-type strain F. ipomoeae LC12165 respectively by pairwise DNA alignments on the FUSARIOID-ID database (https://www.fusarium.org). Phylogenetic analysis of the partial TEF-1α and RPB2 sequences with PhyloSuite (Zhang et al. 2020) showed the isolated fungus clustered with F. ipomoeae. Based on the morphological and phylogenetic analyses, TGGF22-17 was identified as F. ipomoeae. Pathogenicity tests were performed on healthy melons, which were surface-sterilized with 75% alcohol and wounded using a sterilized inoculation needle. A 4-mm diameter plug from a 7-day-old SNA culture of TGGF22-17 was aseptically inserted in the middle of the wound, sealed with plastic bag after absorbent cotton was included to maintain moisture. Five melons were each inoculated at three points. Noncolonized PDA agar plugs served as the negative control. The inoculated and uninoculated plugs were removed approximately 48 hours after inoculation. The melon inoculated with TGGF22-17 exhibited water-soaked black lesions 48h post-inoculation, resulting in a 100% infection rate (15/15). After 7 days, mycelium was obseved on the inoculated melons. No disease symptoms were observed on the uninoculated melons. To fulfill Koch's postulates, fungi were isolated from the inoculated fruit and confirmed as F. ipomoeae by morphological observation. Fusarium ipomoeae has been reported to cause fruit rot on winter squash (Cucurbita maxima) in Japan (Kitabayashi et al. 2023). To our knowledge, this is the first report of fruit rot on muskmelon caused by F. ipomoeae in China and this report will be valuable for monitoring and management of fruit rot disease on muskmelons.

The Morphological Identification of Fungi Causing Cocoa Fruit Rot Disease and Inhibition Test of Bacillus spp. Against the Fungus in Vitro

Cocoa plants in Nagari Bunga Tanjung, West Sumatra Province, are infected with cocoa pod rot disease by the fungal pathogen Phytophthora palmivora and this causes serious problems if not appropriately controlled. Therefore, Bacillus spp testing needs to be undertaken to obtain Bacillus spp that were more capable of inhibiting the growth of the pathogen. The research was conducted at the Plant Disease Laboratory, Faculty of Agriculture, Riau University in February-June 2024. Completely Randomized Design (CRD) were used in this emerimantal study with 5 treatments and 4 replicates so that 20 there were experimental units. The treatments given were: B0 : Without Bacillus spp, B1 : Bacillus amyloliquefaciens, B2: Bacillus cereus, B3: Bacillus pseudomycoides and B4: Bacillus velezensis. Variables observed were the macroscopic and microscopic characteristics of Phytophthora palmivora, the diameter of pathogenic colonies after the application of Bacillus spp. and the inhibition of Bacillus spp. bacteria against Phytophthora palmivora. Further testing was done through Duncan's New Multiple Range Test (DNMRT) at the 5% level. The results of the research conducted showed that the cause of cocoa fruit rot disease in Nagari Bungo Tanjuang is Phytophthora palmivora based on morphological characteristics. All Bacillus spp. namely: Bacillus cereus, Bacillus amyloliquefaciens, Bacillus pseudomycoides, and Bacillus velezensis were able to inhibit the growth of Phytophthora palmivora fungus in vitro. Bacillus cereus, Bacillus amyloliquefaciens, Bacillus pseudomycoides, and Bacillus velezensis were able to inhibit the growth of Phytophthora palmivora in vitro. Phytophthora palmivora with inhibition power of 38.89%, 40.28%, 43.33%, 77.78%, respectively.

First Report of Neofusicoccum parvum Causing Fruit Rot on Psidium guajava in China.

Guava (Psidium guajava L.), a nutrient-rich and economically significant fruit, is extensively cultivated in southern China. In six continuous years (from 2018 to 2023), dark-purple rotted guava with sunken lesion were observed on guava trees (variety 'Zhenzhu', aged over 5 years) in Dongguan and Panyu districts, Guangdong Province. Annually, the incidence of fruit rot disease in the affected fields reached 30% to 50% and significantly reduced the yield and quality of harvest guava. The initial symptoms on the epicarp of the fruits were black, needle-like dots that rapidly spread, causing partial or complete fruit rot within two to three weeks. To identify the causative agent, six symptomatic fruits were collected from two different orchards. Samples of 0.5 cm³ were excised from the lesion margins of each fruit. These samples were surface-sterilized with 70% ethanol for 30 seconds, followed by 0.2% NaClO for 2-3 minutes, and rinsed in sterile water three times. The samples were then cultured on potato dextrose agar (PDA) at 25°C for five days. This process yielded eight fungal isolates with similar morphological. Initially, the colonies were white with dense aerial mycelium becoming dark gray after 4 to 5 days. The mycelia were septate and branched. No spores were observed on PDA. To induce spore formation, the isolates were cultured on water agar for 20 days. This process led to the production of hyaline, aseptate, ellipsoid conidia, which were thin-walled, smooth-surfaced, and measured 3.7-5.1 × 1.6-2.2 μm (n = 100). Three isolates, including at least one from each orchard (Np1, Np2, Np3), were selected for further analysis. Genomic DNA was extracted using Axygen MAG-FRAG-I-50 (Axygen Bio-Tek). The internal transcribed spacer of rDNAs (ITS), beta-tubulin (tub2), the nuclear ribosomal large subunit (LSU), and translation elongation factor 1-α (tef1-α) gene regions were amplified using the primers ITS1/4, Bt2a/Bt2b, LR5/LR0R, and EF1-728F/EF1-986R (Golzar and Burgess 2011) and sequenced. Sequence analysis using MEGA 7.0 (Kumar et al., 2018) revealed 100% similarity among the isolates. BLAST searches of the ITS, tub2, LSU, and tef1-α sequences (accession nos. MN907637, MT537938, MT528156, MT537939) showed the highest nucleotide similarities (99.24 to 100%) to Neofusicoccum parvum strains (Crous et al. 2006). A phylogenetic tree was constructed with MEGA 7.0 based on the nucleotide sequence tub2 using the maximum likelihood method. Pathogenicity tests on 10 healthy guava fruits using mycelium-inoculated and control fruits confirmed the causative agent. The inoculated fruits, maintained at 25°C under a 12-h light/dark cycle, exhibited symptoms identical to the field infections within four to seven days, while control fruits remained symptomless. The fungus, reisolated from the inoculated fruits, was morphologically identical to the original isolates, fulfilling Koch's postulates. In conclusion, based on molecular, morphological, and pathogenic analysis, N. parvum as the causal agent of the fruit rot disease on guava. Previously, N. parvum has been reported in association with fruit rot on Eriobotrya japonica and Juglans regia (Zhai et al. 2019; Chen et al. 2019). To our knowledge, this is the first report of N. parvum affecting guava in China.

Insights into the population dynamics of phytophthora species associated with arecanut fruit rot disease

Phytophthora, a ubiquitous filamentous oomycete, causes huge yield losses and is fatal to arecanut palms in case of severe infection. From 2014 onwards, a severe fruit rot epidemic has been recorded during the South-West monsoon season in major arecanut-growing states of South India. We have assessed the diversity and delineated the population structure of Phytophthora isolates infecting arecanut in India using a combination of morphological traits, multi-gene profiling, haplotype analysis, and pathogenicity. Ninety-eight Phytophthora isolates were obtained from infected samples collected from disease-endemic regions of Karnataka, Kerala, and Goa states in southern India from 2014 to 2019. Morphological traits coupled with phylogenetic analysis using the loci ITS, β-tub, TEF-1α, and Cox-II identified the A2 mating type of P. meadii as the predominant species together with two isolates of homothallic P. heveae. Linkage disequilibrium analysis revealed significant diversity in the form of single nucleotide polymorphisms (SNPs) from the concatenated sequence dataset. Population structure analysis using 590 SNPs demonstrated the existence of four population groups (sub-populations at K = 4 and K = 2) and significant diversity in the geo-distant Phytophthora populations. In summary, 22 haplotypes were identified from the representative 40 isolates with higher haplotype diversity of 1.23 and relatively varying haplotype frequency. Pathogenicity assays confirmed that both the species of Phytophthora were pathogenic to arecanut, while P. meadii coastal region isolates exhibited more virulence compared to others.

Điều tra bệnh hại sau thu hoạch trên giống chuối Tiêu hồng (Musa acuminata) và chuối Nam Mỹ (Musa paradisiaca) ở Việt Nam

The survey implemented in the 2021 winter season on the Tieu hong banana cultivar (Musa acuminata) grown in Phu Tho and Hung Yen provinces showed that the most severe diseases were fruit rot and fruit spot with infection rates of 79.1% and 75.5%, respectively. Peel cracking and end rot (cigar rot) were also recorded at less than 5.0%. Fruit spot was the main disease that affected the South-American banana cultivar (Musa paradisiaca) during the 2022 spring-summer season in Gia Lai province. Of the 24 fungal and 37 bacterial strains isolated from the disease samples collected during the investigation and tested for their pathogenicity via artificial infection on healthy bananas, only 17 fungal strains showed the ability of lesion formation of which 4 strains caused typical symptoms of the fruit rot disease. There was not a single bacterial strain ascertained as phytopathogen indicating that fungi were the primary agents of post-harvest diseases on bananas. These four fungal strains were taxonomically characterized based on their morphology (colony and spore), comparative analysis of the ITS sequences of the 18S rDNA gene, and were then identified as Corynespora torulosa B2B, Microdochium colombiense B6, Fusarium circinatum B13F, and Aspergillus niger GL2.1. The ITS sequences of these strains were deposited to GenBank under the accession numbers OP855524, OP855525, OP855526, and OP855527, respectively.

Pathological investigation and morpho-molecular characterisation of Lasiodiplodia theobromae causing fruit rot diseases on Hydnocarpus longipedunculatus – A novel host record from India

Hydnocarpus longipedunculatus, a medically significant tree species, is threatened and has a narrow distribution, being endemic to the Southern Western Ghats of India. A case of fruit rot disease was observed in a solitary tree of H. longipedunculatus in the Kulamavu forest areas of Kerala, India. The causative fungus, Lasiodiplodia theobromae, was isolated and identified through a combination of morpho-cultural characteristics and molecular sequence analysis involving the internal transcribed spacer (ITS), partial translation elongation factor-1-α (TEF1-α), partial β-tubulin (TUB2), and large subunit ribosomal ribonucleic acid (LSU) regions. Additionally, concatenated multigene (ITS-TEF1-α-TUB2) phylogenetic analysis was done. Pathogenicity tests were conducted in vitro using mycelial disc methods and confirmed the pathogenic nature of the fungus through re-isolation and morphocultural analysis, satisfying Koch's postulates. Previous studies neither have reported H. longipedunculatus as a host for L. theobromae, nor has any genus within Hydnocarpus. Therefore, this represents the first documented instance of H. longipedunculatus as a novel host record for L. theobromae from India.

Potential biocontrol agents involved in induction of defense related enzymes in brinjal (solanum melongena l.) Against phomopsis blight caused by phomopsis vexans

Phomopsis blight, caused by Phomopsis vexans (P. vexans) in brinjal plants is one of the main diseases in India. In order to manage this malady, we initially screened seed samples of 14 cultivars obtained from seed suppliers for the disease incidence. Based on the disease incidence and severity, the samples were categorized as resistant and susceptible cultivars of brinjal. It was established that MEBH-9' was a sensitive cultivar, while the Kolar local was resistant to the disease. Two ideal strains of Rhizosphere colonizing bacteria (RCB), Pseudomonas putida strain Has-1/c (HM229805), and Phylloplane Colonizing Bacteria (PCB), Bacillus subtilis strain Br/ph-33 (KJ867501), previously characterized as potential plant growth-promoting rhizobacteria, were tested for their potential biocontrol of this disease. Both susceptible and resistant cultivars' seedlings were treated with different combinations of PCB and RCB, PCB alone, RCB alone, and challenge inoculated with P. vexans. In order to ascertain whether there was signalling between defense enzyme activation and plant protection after PCB and RCB treatment, defense enzymes were quantified. Brinjal plants treated with PCB+RCB combination and challenge inoculated with P. vexans showed a significant increase in the activity of Phenylalanine ammonia-lyase (PAL), Peroxidase (POX), Lipoxygenase (LOX), Polyphenol oxidase (PPO), Catalase, Chitinase, β -1,3-glucanase, and Hydrogen peroxide (H2O2) content. The current study reveals that the defense enzymes and PR-proteins are gradually induced and accumulated, which enhance the resistance in brinjal plants against P. vexans-causing fruit rot disease.

First Report of Neofabraea actinidiae causing a Cranberry Fruit Rot in Oregon.

Cranberry (Vaccinium macrocarpon, L.) is a commercial small fruit that is native to North America. Oregon ranks fourth in cranberry production in the U.S.A. with 1052 Ha of cranberry beds and annual production of 23,590 metric tonnes (USDA NASS 2021). Cranberry fruit rot diseases are caused by a complex of 15 fungal pathogens belonging to 10 genera (Polashock et al. 2017). In fruit rot surveys of 'Stevens' cranberry beds in Coos and Curry Counties, Oregon, berries were collected before harvest and sorted by symptoms (e.g. softening, shriveling, or discoloration). Cranberries with field rot symptoms were surface-disinfested and lesion margin tissue placed on V8 agar. Cultures were incubated at room temperature and outgrowing fungi were transferred twice onto fresh V8 agar to obtain single isolates. Storage rots that developed on asymptomatic cranberries held at 4°C for 8 weeks were processed similarly. Since 2017, we periodically isolated Neofabraea actinidiae, which is not a member of the cranberry fruit rot complex, from rotted cranberries (Polashock et al. 2017). In 2022, N. actinidiae was isolated from 22% of 45 cranberries collected from an organically managed farm and developed storage rot and from 6% of 50 storage-rot cranberries from three conventionally managed farms. Symptoms associated with N. actinidiae on 'Stevens' cranberries often include softening and brown tissue surrounded by a yellow-colored ring. On V8 agar, N. actinidiae grew as compact white circular colonies with dense aerial hyphae near the center and accompanied by a red pigment in the agar. Pink-colored mucoidal irregular conidiomata often developed on the colony after 3 weeks. Conidia were hyaline, aseptate, and ellipsoidal to fusiform ranging from 7.5 to 12.6 µm long X 3.5 to 5.6 µm wide (n=100). Genomic DNA was extracted from N. actinidiae isolates from cranberries in 2017 and 2022. β-tubulin and the ITS 5/4 region were amplified and sequenced with primers Bt-T2m-Up/Bt-LEV-Lo1 and ITS5/ITS4 using conditions of de Jong et al. (2001) and White et al. (1990), respectively. Sequences were deposited in NCBI Genbank (Accessions: OR606303, OR606305, OR606306, & OR606309 for ITS; OR610314, OR610316, OR610317, & OR610320 for β-tubulin). BlastN analysis of β-tubulin (695 bp) and ITS (489-490 bp) had a 99.6 to 99.8% and 99.8 to 100% identity, respectively, to Neofabraea actinidiae (CBS 121403) (Accession numbers: KR859285 β-tubulin and KR859079 ITS). Phylogenetic analysis of concatenated sequences using Tamura-Nei neighbor-joining (Tamura et al. 2004) confirmed identity of cranberry isolates as N. actinidiae. Koch's Postulates were confirmed with four N. actinidiae isolates from cranberry. Agar or hyphal plugs were placed in a 3 mm wound on the side of six surface-disinfested, asymptomatic berries and incubated in a moist chamber at 20°C for 15 days or 4°C for 55 days. Similar symptoms developed on each berry inoculated with N. actinidiae, but not agar alone. The fungus was recovered from symptomatic tissues and identity confirmed by colony morphology. N. actinidiae causes a ripe rot and storage rot in kiwifruit and is one of the species causing Bull's Eye Rot of pome fruits (Tyson et al. 2019). Cryptosporiopsis actinidiae (anamorph) was isolated from cranberries roots in British Columbia, CA, but considered unlikely to be the causal agent of dieback disease of cranberry vines (Sabaratnam et al. 2009). We have demonstrated that N. actinidiae causes a cranberry fruit rot in beds and in storage. Its prevalence, associated fruit rot symptoms, and disease incidence will continue to be monitored.

Pest Status of Subfamily Lymantriinae (Lepidoptera: Erebidae: Noctuoidea): Review

Plant diseases and pests are important factors determining plant yield production, including mango. Mango fruit rot caused by insects and microbes has become a significant threat to mango production in Southeast Asia and worldwide. Insect plant pathogens affect crop yields' profitability, quality, and quantity. Some infections could occur before harvest and remain dormant until the favourable condition is achieved, and the disease will break out after harvest, reducing mango production. They act as a threat to the crops through various mechanisms of pathogenesis that compromise the immune system of the plants, such as developing any ways to attack the plants, seeking entry via open pores or exposed surface or wound, and sourcing nutrients forcefully for their growth and development. Depending on the environmental factors, the insect contracts the host through primary or secondary infection. This paper summarizes mango fruit rot disease caused by insects groups such as fruit borers (Autocharis albizonalis and Citripestis eutraphera), fruit flies (Bactrocera dorsalis), and mango seed weevils (Sternochetus mangiferae). This review will provide information about fruit rot diseases on mangoes caused by insects, the mechanism of infection, the interaction between insect damage and fungal infections, effective control methods, and related integrated pest management approaches.

Insects Induced Mango Fruit Rot: Unraveling the Culprits

Plant diseases and pests are important factors determining plant yield production, including mango. Mango is an economically important fruit crop in tropical and subtropical areas. Mango fruit rot caused by insects and microbes has become a significant threat to mango production in Southeast Asia and worldwide. Insect plant pathogens affect crop yields' profitability, quality, and quantity. Some infections could occur before harvest and remain dormant until the favourable condition is achieved, and the disease will break out after harvest, reducing mango production. They act as a threat to the crops through various mechanisms of pathogenesis that compromise the immune system of the plants, such as developing any ways to attack the plants, seeking entry via open pores or exposed surface or wound, and sourcing nutrients forcefully for their growth and development. Depending on the environmental factors, the insect contracts the host through primary or secondary infection. This paper summarizes mango fruit rot disease caused by insects groups such as fruit borers (Autocharis albizonalis and Citripestis eutraphera), fruit flies (Bactrocera dorsalis), and mango seed weevils (Sternochetus mangiferae). This review will provide information about fruit rot diseases on mangoes caused by insects, the mechanism of infection, the interaction between insect damage and fungal infections, effective control methods, and related integrated pest management approaches.

First report of Botryosphaeria dothidea causing fruit rot on Chinese olive (Canarium album Raeusch.) in Guangdong province of China.

Chinese olive (Canarium album Raeusch.) is a traditional Chinese medicinal plant, mainly cultivated in Guangdong and Fujian provinces in China (Lai et al. 2022). In October 2023, Chinese olive fruit spots were observed in all the Chinese olive orchards surveyed in Chaozhou city (23.75°N, 116.67°E) of Guangdong, with an incidence up to 15%. Early disease symptoms on fruits appeared as circular or irregular, dark brown to black spots with yellowish lesions, and later the spots slowly coalesced to form large necrotic areas, which seriously affected the fruit marketability. To isolate the causal agent, small pieces (~0.3 mm2) of fruit tissue were excised from the lesion margins, and surface-disinfested with 75% (v/v) ethanol for 1 min, followed by 1% NaClO for 3 min, and rinsed three times with sterile water. The pieces were then placed on potato-dextrose-agar (PDA) and incubated at 27°C. Ultimately, four fungal isolates were obtained with similar morphology phenotypes, colonies initially appeared white with irregular margins and after 4-6 days turned dark gray gradually with dense aerial myceliu. Microscopy revealed conidia were single-celled, hyaline, aseptate, fusiform to subclavate, and measured 18.1-22.5 μm × 6.4-9.3 μm (19.8 × 7.4 m on average, n = 30), which were consistent with those descriptions of Botryosphaeria dothidea (Vasić et al. 2013; Zhang et al. 2023). To further identity the isolates, partial sequences of ribosomal transcribed spacer (ITS), translation elongation factor 1-α (TEF1-α), and β-tubulin (TUB2) genes were amplified using primers ITS1/ITS5, TEF-F/R, TUB2-F/R, respectively (Xu et al., 2023; Hong et al. 2006). The sequences of four isolates were identical, and those of representative strain GDCZ-1 were deposited in GenBank (ITS, OR584295; TEF1-α, OR685157; TUB2, OR685158). Using Neighbor-Joining algorithm, phylogenetic tree based on concatenated sequences of ITS, TEF1-α, and TUB2 showed that GDCZ-1 clustered with B. dothidea. To fulfill Koch's postulates, pathogenicity tests were performed on healthy Chinese olive fruits using the needle-prick inoculation method. The fruits were wounded with a sterile needle at the equatorial area (depth of 3-4 mm), and inoculated with 10 µL of spore suspension (106 /mL). The control fruits were inoculated with sterile water. Inoculated fruits were placed in sterile plastic containers to maintain high relative humidity (almost 100%) and incubated at 27°C. After 4 days, the inoculated fruits showed similar symptoms with those observed in the field infected fruits, while the control remained asymptomatic. Pathogen re-isolated from the inoculated fruits showed identical morphological characteristics to the original isolate GDCZ-1. As far as we know, fruit rot caused by Alternaria alternata has been recently reported on C. album in China (Shao et al. 2024). To our knowledge, this is the first report of B. dothidea causing fruit rot disease on C. album in Guangdong. Our report will provide crucial information for studying the epidemiology and management of this disease.

In silico analysis to understand genetic variability, phylogenetic and phylogeographic relationships between Phytophthora capsici isolates infecting various crops

Phytophthora capsici is a major oomycete-based pathogen causing enormous damage to the productivity of peppers and other major crops from different families worldwide by causing fruit rot, root rot and foliar blight diseases. This study utilized molecular signatures present within ITS1-5.8S rRNA-ITS2 and Ras-related GTP binding protein (Ypt1) genes to evaluate haplotype variability and phylogenetic relationships among P. capsici isolates with significant epidemiological implications. Twelve different evolutionary lineages specific to particular hosts and/or geographical regions and differed by SNPs, and 30 haplotypes with maximum diversity in India and Pakistan, were identified by sequence analysis of the ITS regions. It includes country-specific lineages Pc-I and Pc-II in India with multiple host ranges; capsicum-specific lineages Pc-IV, Pc-V and Pc-VIII from Pakistan; papaya-specific lineages Pc-VI from China, and watermelon-specific lineages Pc-VII and Pc-XI from USA. Many lineages showed cross-border infections, such as Pc-III and Pc-X in India and Pakistan, Cocoa-specific lineage Pc-IX in Brazil and Cote d’Ivoire, and Capsicum-specific multi-continental lineage Pc-XII. Similarly, 11 different SNP lineages and 32 haplotypes with maximum diversity in China were identified for the Ypt1 gene. These findings would be very useful for epidemiological surveillance of P. capsici strains worldwide, understanding population and evolutionary dynamics, developing lineage- and haplotype-specific diagnostic assays and disease-resistant varieties.

Fus3 is a pathogenicity factor of Botryosphaeria dothidea on kiwifruit

AbstractThe ascomycete fungus Botryosphaeria dothidea is the causal agent of postharvest rot in kiwifruit. Production and spreading of conidia, differentiation of infection hyphae and invasion of intact fruit surfaces are required to cause fruit rot disease. In several pathogenic fungi, the homologue of the Saccharomyces cerevisiae mitogen activated protein kinase (MAPK) gene Fus3 has been identified as a pathogenicity factor. To investigate the role of the Fus3 homologue in B. dothidea, the gene was deleted and the resulting ∆fus3 mutants were characterized. On artificial media, strong growth defects of ∆fus3 strains were observed, mycelia were non‐pigmented, and mutants were unable to conidiate. Scanning electron microscopy showed that the wild‐type strain differentiated thick hyphae on the surface of kiwifruits, and nose‐down growth of hyphae indicated tight attachment to the fruit. In contrast, hyphae of ∆fus3 strains mutants were thinner and did not firmly attach to the fruit surface. Importantly, pathogenicity test revealed that ∆fus3 strains were unable to cause disease symptoms on intact kiwifruits. These results shown here identify Fus3 of B. dothidea as a novel pathogenicity factor of the ripe rot pathogen on kiwifruit.