Citrus industry: Phytoplasma-associated diseases and related challenges for Asia, America and Africa

Noorizadeh, Sina; Golmohammadi, Morteza; Bagheri, Abdoolnabi; Bertaccini, Assunta

doi:10.1016/j.cropro.2021.105822

Cited by 10 publications

(3 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Putative vectors of ‘ Ca. Phytoplasma citri’ include Diaphorina citri Kuwayama (Hemiptera: Psyllidae) and Hishimonus phycitis Distant (Hemiptera: Cicadellidae) [93]. ‘ Ca.…”

Section: Discussionmentioning

confidence: 99%

The observation of taxonomic boundaries for the 16SrII and 16SrXXV phytoplasmas using genome-based delimitation

Jardim

Tran-Nguyen²,

Gambley³

et al. 2023

International Journal of Systematic and Evolutionary Microbiology

View full text Add to dashboard Cite

Within the 16SrII phytoplasma group, subgroups A–X have been classified based on restriction fragment length polymorphism of their 16S rRNA gene, and two species have been described, namely ‘Candidatus Phytoplasma aurantifolia’ and ‘Ca. Phytoplasma australasia’. Strains of 16SrII phytoplasmas are detected across a broad geographic range within Africa, Asia, Australia, Europe and North and South America. Historically, all members of the 16SrII group share ≥97.5 % nucleotide sequence identity of their 16S rRNA gene. In this study, we used whole genome sequences to identify the species boundaries within the 16SrII group. Whole genome analyses were done using 42 phytoplasma strains classified into seven 16SrII subgroups, five 16SrII taxa without official 16Sr subgroup classifications, and one 16SrXXV-A phytoplasma strain used as an outgroup taxon. Based on phylogenomic analyses as well as whole genome average nucleotide and average amino acid identity (ANI and AAI), eight distinct 16SrII taxa equivalent to species were identified, six of which are novel descriptions. Strains within the same species had ANI and AAI values of >97 %, and shared ≥80 % of their genomic segments based on the ANI analysis. Species also had distinct biological and/or ecological features. A 16SrII subgroup often represented a distinct species, e.g., the 16SrII-B subgroup members. Members classified within the 16SrII-A, 16SrII-D, and 16SrII-V subgroups as well as strains classified as sweet potato little leaf phytoplasmas fulfilled criteria to be included as members of a single species, but with subspecies-level relationships with each other. The 16SrXXV-A taxon was also described as a novel phytoplasma species and, based on criteria used for other bacterial families, provided evidence that it could be classified as a distinct genus from the 16SrII phytoplasmas. As more phytoplasma genome sequences become available, the classification system of these bacteria can be further refined at the genus, species, and subspecies taxonomic ranks.

show abstract

“…Putative vectors of ‘ Ca. Phytoplasma citri’ include Diaphorina citri Kuwayama (Hemiptera: Psyllidae) and Hishimonus phycitis Distant (Hemiptera: Cicadellidae) [93]. ‘ Ca.…”

Section: Discussionmentioning

confidence: 99%

The observation of taxonomic boundaries for the 16SrII and 16SrXXV phytoplasmas using genome-based delimitation

Jardim

Tran-Nguyen²,

Gambley³

et al. 2023

International Journal of Systematic and Evolutionary Microbiology

View full text Add to dashboard Cite

show abstract

“…Citrus is one of the largest grown fruit crops in various tropical and subtropical regions of the world, including Brazil, China, USA, India, Pakistan, Italy, Spain, Australia, and Argentina. The genus Citrus includes various species of oranges, mandarins, grapefruits, limes, and lemons, which belong to Rutaceae [1,2]. The production of citrus is limited by biotic (insect pests and pathogens) and abiotic factors (temperature, humidity, soil conditions, and availability of water).…”

Section: Introductionmentioning

confidence: 99%

Ecology, Biology, Damage, and Management of Sucking and Chewing Insect Pests of Citrus

Afzal¹,

Banazeer²,

Serrão³

et al. 2023

Citrus Research - Horticultural and Human Health Aspects

View full text Add to dashboard Cite

Citrus are important commodities for human and animal nutrition but these crops are attacked by a plethora of dangerous agents, including viruses, bacteria, fungi, and invertebrates that decrease the yield significantly. Within invertebrates, insects are the more prevalent citrus pests causing plant damage or act as diseases vector. In this chapter, we focused in the insect pests with worldwide distribution in citrus orchards, including sap sucking Asian citrus psyllid Diaphorina citri, citrus mealybug Planococcus citri, citrus whitefly Dialeurodes citri, thrips representatives such as Scirtothrips citri and Pezothrips kellyanus, and chewing citrus leafminer Phyllocnistis citrella and lemon butterfly Papilio demoleus. These pests are distributed across various regions of different continents such as in Asia-pacific, Americas, Africa, and Oceana. We presented detailed data from these pests’ biology, ecology, damage, and methods for control. The pest incidence and biology is affected by various biotic and abiotic factors thus providing the opportunity to use these factors as method of intervention to disturb pest life cycle. In this context, several IPM techniques such as cultural, physical, biological, and chemical methods were elaborated, which could help to reduce the pest status below damaging levels.

show abstract

“…Citrus plays an essential role in the fruit industry around the world, with an annual production of approximately 140 million tons (Zheng et al, 2021;Noorizadeh et al, 2022). As the cost of fruit harvesting increases and the availability of skilled labor decreases in China, the traditional manual harvesting method is no longer practical (Gongal et al, 2015;Tang et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

Detection and localization of citrus fruit based on improved You Only Look Once v5s and binocular vision in the orchard

et al. 2022

View full text Add to dashboard Cite

Intelligent detection and localization of mature citrus fruits is a critical challenge in developing an automatic harvesting robot. Variable illumination conditions and different occlusion states are some of the essential issues that must be addressed for the accurate detection and localization of citrus in the orchard environment. In this paper, a novel method for the detection and localization of mature citrus using improved You Only Look Once (YOLO) v5s with binocular vision is proposed. First, a new loss function (polarity binary cross-entropy with logit loss) for YOLO v5s is designed to calculate the loss value of class probability and objectness score, so that a large penalty for false and missing detection is applied during the training process. Second, to recover the missing depth information caused by randomly overlapping background participants, Cr-Cb chromatic mapping, the Otsu thresholding algorithm, and morphological processing are successively used to extract the complete shape of the citrus, and the kriging method is applied to obtain the best linear unbiased estimator for the missing depth value. Finally, the citrus spatial position and posture information are obtained according to the camera imaging model and the geometric features of the citrus. The experimental results show that the recall rates of citrus detection under non-uniform illumination conditions, weak illumination, and well illumination are 99.55%, 98.47%, and 98.48%, respectively, approximately 2–9% higher than those of the original YOLO v5s network. The average error of the distance between the citrus fruit and the camera is 3.98 mm, and the average errors of the citrus diameters in the 3D direction are less than 2.75 mm. The average detection time per frame is 78.96 ms. The results indicate that our method can detect and localize citrus fruits in the complex environment of orchards with high accuracy and speed. Our dataset and codes are available at https://github.com/AshesBen/citrus-detection-localization.

show abstract

Citrus industry: Phytoplasma-associated diseases and related challenges for Asia, America and Africa

Cited by 10 publications

References 40 publications

The observation of taxonomic boundaries for the 16SrII and 16SrXXV phytoplasmas using genome-based delimitation

The observation of taxonomic boundaries for the 16SrII and 16SrXXV phytoplasmas using genome-based delimitation

Ecology, Biology, Damage, and Management of Sucking and Chewing Insect Pests of Citrus

Detection and localization of citrus fruit based on improved You Only Look Once v5s and binocular vision in the orchard

Contact Info

Product

Resources

About