Hevea Rubber Tree

Rubber tree Corynespora leaf fall (CLF) disease, caused by the fungus Corynespora cassiicola, is one of the most damaging diseases in rubber tree plantations in Asia and Africa, and this disease also threatens rubber nurseries and young rubber plantations in China. C. cassiicola isolates display high genetic diversity, and virulence profiles vary significantly depending on cultivar. Although one phytotoxin (cassicolin) has been identified, it cannot fully explain the diversity in pathogenicity between C. cassiicola species, and some virulent C. cassiicola strains do not contain the cassiicolin gene. In the present study, we report high-quality gapless genome sequences, obtained using short-read sequencing and single-molecule long-read sequencing, of two Chinese C. cassiicola virulent strains. Comparative genomics of gene families in these two stains and a virulent CPP strain from the Philippines showed that all three strains experienced different selective pressures, and metabolism-related gene families vary between the strains. Secreted protein analysis indicated that the quantities of secreted cell wall-degrading enzymes were correlated with pathogenesis, and the most aggressive CCP strain (cassiicolin toxin type 1) encoded 27.34% and 39.74% more secreted carbohydrate-active enzymes (CAZymes) than Chinese strains YN49 and CC01, respectively, both of which can only infect rubber tree saplings. The results of antiSMASH analysis showed that all three strains encode ~60 secondary metabolite biosynthesis gene clusters (SM BGCs). Phylogenomic and domain structure analyses of core synthesis genes, together with synteny analysis of polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) gene clusters, revealed diversity in the distribution of SM BGCs between strains, as well as SM polymorphisms, which may play an important role in pathogenic progress. The results expand our understanding of the C. cassiicola genome. Further comparative genomic analysis indicates that secreted CAZymes and SMs may influence pathogenicity in rubber tree plantations. The findings facilitate future exploration of the molecular pathogenic mechanism of C. cassiicola.

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Anopheles ecology, genetics and malaria transmission in northern Cambodia

Scientific Reports ◽

10.1038/s41598-021-85628-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Amélie Vantaux ◽

Michelle M. Riehle ◽

Eakpor Piv ◽

Elise J. Farley ◽

Sophy Chy ◽

...

Keyword(s):

Malaria Transmission ◽

Mosquito Species ◽

Rubber Tree ◽

Amplicon Sequencing ◽

Forest Sites ◽

Baited Traps ◽

Residual Malaria Transmission ◽

Mosquito Ecology ◽

Forested Areas ◽

Greater Mekong Subregion

AbstractIn the Greater Mekong Subregion, malaria cases have significantly decreased but little is known about the vectors or mechanisms responsible for residual malaria transmission. We analysed a total of 3920 Anopheles mosquitoes collected during the rainy and dry seasons from four ecological settings in Cambodia (villages, forested areas near villages, rubber tree plantations and forest sites). Using odor-baited traps, 81% of the total samples across all sites were collected in cow baited traps, although 67% of the samples attracted by human baited traps were collected in forest sites. Overall, 20% of collected Anopheles were active during the day, with increased day biting during the dry season. 3131 samples were identified morphologically as 14 different species, and a subset was also identified by DNA amplicon sequencing allowing determination of 29 Anopheles species. The investigation of well characterized insecticide mutations (ace-1, kdr, and rdl genes) indicated that individuals carried mutations associated with response to all the different classes of insecticides. There also appeared to be a non-random association between mosquito species and insecticide resistance with Anopheles peditaeniatus exhibiting nearly fixed mutations. Molecular screening for Plasmodium sp. presence indicated that 3.6% of collected Anopheles were positive, most for P. vivax followed by P. falciparum. These results highlight some of the key mechanisms driving residual human malaria transmission in Cambodia, and illustrate the importance of diverse collection methods, sites and seasons to avoid bias and better characterize Anopheles mosquito ecology in Southeast Asia.

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Ethrel® stimulant increases the activity of soluble invertase isoforms in rubber tree (Hevea brasiliensis) bark tissues

Australian Journal of Crop Science ◽

10.21475/ajcs.18.12.01.pne770 ◽

2018 ◽

Vol 12 (1) ◽

pp. 99-107

Author(s):

Débora Domiciano ◽

◽

Pollyanna Aparecida Carvalho ◽

Luiz Edson Mota de Oliveira ◽

Hilda Beatriz W. Cárdenaz ◽

...

Keyword(s):

Hevea Brasiliensis ◽

Rubber Tree

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Evidence in Practice of Tissue Healing with Latex Biomembrane: Integrative Review

Journal of Diabetes Research ◽

10.1155/2019/7457295 ◽

2019 ◽

Vol 2019 ◽

pp. 1-17 ◽

Cited By ~ 1

Author(s):

Suélia de Siqueira Rodrigues Fleury Rosa ◽

Mário Fabrício Fleury Rosa ◽

Marcos Augusto Moutinho Fonseca ◽

Glécia Virgolino da Silva Luz ◽

Carlos Federico Domínguez Avila ◽

...

Keyword(s):

Diabetes Mellitus ◽

Wound Healing ◽

Chronic Diseases ◽

Low Cost ◽

Rubber Tree ◽

Antimicrobial Effect ◽

Integrative Review ◽

Complication Rates ◽

Biocompatible Material ◽

Tissue Healing

Wound healing is a perfectly coordinated cascade of cellular, molecular, and biochemical events which interact in tissue reconstitution. Chronic diseases such as pressure ulcers (PU) and diabetes mellitus (DM) are considered risk factors for wound healing. Patients with such diseases often have higher sepsis, infection, and complication rates, since they have revascularization inhibition and low growth factor expression. Thus, latex biomembrane (LBM), a biocompatible material, derived from the latex of the rubber tree (Hevea brasiliensis) appears to create tendencies as an angiogenic-inducing tissue healing agent and as biomaterial, resulting from its structural qualities and its low cost when compared to conventional treatments. Therefore, this work aims at summarizing the results, experiments, and scientific findings that certify or recommend the use of LBM as a new technique to be applied effectively in the treatment of wounds. An integrative review was held in the BIREME, LILACS, Burns, MEDLINE, PubMed, and SciELO databases, from 2000 to 2016, using the following descriptors: “healing,” “diabetes mellitus,” “wounds,” and “latex membrane.” As a result, 600 experiments (out of 612) presented satisfactory results; however, 33% of the cases received explicit recommendations, 11% required more studies on the subjects, and 1% was denied. On the other hand, half of the studies did not expressly endorse its use, despite presenting satisfactory results. The LBM was characterized as a good therapeutic alternative in cases of wounds, including chronic diseases, such as diabetes mellitus and PU, due to its relevant potential for wound healing stimulation, acceleration of cell tissue mending and revascularization, or the reestablishment of angiogenic functions (creation of new blood vessels). The LBM was also confirmed to be safe as a biocompatible material whose structural qualities (elasticity, adaptability, impermeability, and possibility of suture), devoid of toxicity, allowed interaction between tissues and presented no hypersensitivity inducer and no antimicrobial effect.

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The Technology Research on Cutting Test of 4GXJ-I Tapping Knife for Rubber Tree

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/592/1/012070 ◽

2019 ◽

Vol 592 ◽

pp. 012070

Author(s):

Chang Huang ◽

Lingling Wang ◽

Jianhua Cao ◽

Yong Zheng ◽

Sihao Wu

Keyword(s):

Rubber Tree ◽

Technology Research ◽

Cutting Test

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