Touchdown treatment of root trainer shortened the formation time of root mass of rubber tree seedlings

This study aimed to evaluate the quality of Hevea brasiliensis seedlings, a GT1 clone, produced in protected environments in a variety of substrates. The treatments consisted of 13 substrates composed of combinations of cattle manure, soil from a ravine, medium vermiculite, superfine vermiculite and washed fine sand and two environments: a greenhouse with 50% shade using aluminized screen and a plant nursery with 50% shade using a Sombrite® screen. There were no replications of the environments; therefore, each one was considered an experiment. For each environment, a completely randomized experimental design with five replications was used to evaluate the substrates. Subsequently, the average squares of the residuals of individual variance analyses of these treatments (substrates) were evaluated, and because they did not exceed an approximate ratio of 7:1, a combined analysis of experiments was performed with Sisvar software. Two hundred eighty days after sowing, the dry weight, plant height, stem diameter, diameter at five centimeters above soil and the seedling quality indices were evaluated. Results indicated that substrates with a low amount of manure and sand and a high amount of vermiculite (S9 and S13) produced rubber tree seedlings of high-quality. The environment with greater radiation availability was better for the development of high-quality rubber tree seedlings.

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Transcriptome analysis of Pará rubber tree (H. brasiliensis) seedlings under ethylene stimulation

BMC Plant Biology ◽

10.1186/s12870-021-03196-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yoshimi Nakano ◽

Nobutaka Mitsuda ◽

Kohei Ide ◽

Teppei Mori ◽

Farida Rosana Mira ◽

...

Keyword(s):

Gene Expression ◽

Cell Wall ◽

Natural Rubber ◽

Management Practices ◽

Rubber Tree ◽

Raw Material ◽

Tree Seedlings ◽

Cell Wall Formation ◽

Wall Formation ◽

Ethephon Treatment

Abstract Background Natural rubber (cis-1,4-polyioprene, NR) is an indispensable industrial raw material obtained from the Pará rubber tree (H. brasiliensis). Natural rubber cannot be replaced by synthetic rubber compounds because of the superior resilience, elasticity, abrasion resistance, efficient heat dispersion, and impact resistance of NR. In NR production, latex is harvested by periodical tapping of the trunk bark. Ethylene enhances and prolongs latex flow and latex regeneration. Ethephon, which is an ethylene-releasing compound, applied to the trunk before tapping usually results in a 1.5- to 2-fold increase in latex yield. However, intense mechanical damage to bark tissues by excessive tapping and/or over-stimulation with ethephon induces severe oxidative stress in laticifer cells, which often causes tapping panel dryness (TPD) syndrome. To enhance NR production without causing TPD, an improved understanding of the molecular mechanism of the ethylene response in the Pará rubber tree is required. Therefore, we investigated gene expression in response to ethephon treatment using Pará rubber tree seedlings as a model system. Results After ethephon treatment, 3270 genes showed significant differences in expression compared with the mock treatment. Genes associated with carotenoids, flavonoids, and abscisic acid biosynthesis were significantly upregulated by ethephon treatment, which might contribute to an increase in latex flow. Genes associated with secondary cell wall formation were downregulated, which might be because of the reduced sugar supply. Given that sucrose is an important molecule for NR production, a trade-off may arise between NR production and cell wall formation for plant growth and for wound healing at the tapping panel. Conclusions Dynamic changes in gene expression occur specifically in response to ethephon treatment. Certain genes identified may potentially contribute to latex production or TPD suppression. These data provide valuable information to understand the mechanism of ethylene stimulation, and will contribute to improved management practices and/or molecular breeding to attain higher yields of latex from Pará rubber trees.

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The Application of Topographical Survey and the Arcgis Spatial Analys “Darcy Flow” Tool in Managing the Nurseries of Rubber Tress

International Letters of Natural Sciences ◽

10.18052/www.scipress.com/ilns.18.100 ◽

2014 ◽

Vol 18 ◽

pp. 100-104 ◽

Cited By ~ 1

Author(s):

M.A. Eboigbe ◽

F.O. Obasogie ◽

I. Alasah ◽

D.J. Idiata

Keyword(s):

Field Data ◽

Continuous Monitoring ◽

Rubber Tree ◽

Surface Flow ◽

Geographical Information ◽

Management Technique ◽

Accurate Information ◽

Tree Seedlings ◽

Geospatial Technique ◽

Nursery Management

Farmers often rely on the physical appearance of rubber tree seedlings to decipher on growth rate. In situations of doubt especially when there is obvious reduction in chlorophyll or coax decay of roots, the most likely situation is induction by flooding. A sound nursery management technique which is both responsive to continuous monitoring of the terrain and also able to generate data for restoration is most desired. This study therefore employs a geospatial technique whereby topographical survey was used to pick field data while Geographical Information System analyses was able to generate accurate information on areas likely to both surface and underground discharge of materials. This method was also able to sum up all affected areas, alongside other attributes like the direction of surface flow and the rate of discharge.

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First Report of Black Root Disease Caused by Chaetomium globosum on Rubber Tree Seedlings in Yunnan, China

Plant Disease ◽

10.1094/pdis-06-18-0956-pdn ◽

2019 ◽

Vol 103 (4) ◽

pp. 763 ◽

Cited By ~ 1

Author(s):

G. Z. Jiang ◽

F. Gao ◽

J. Liu ◽

Y. X. Liu ◽

Y. P. Shi ◽

...

Keyword(s):

Rubber Tree ◽

Root Disease ◽

Chaetomium Globosum ◽

Tree Seedlings ◽

First Report

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Transcriptomic analyses reveal molecular mechanisms underlying growth heterosis and weakness of rubber tree seedlings

BMC Plant Biology ◽

10.1186/s12870-017-1203-3 ◽

2018 ◽

Vol 18 (1) ◽

Cited By ~ 3

Author(s):

Hong Yang ◽

Xuncheng Wang ◽

Yongxuan Wei ◽

Zhi Deng ◽

Hui Liu ◽

...

Keyword(s):

Molecular Mechanisms ◽

Rubber Tree ◽

Tree Seedlings

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Rubber tree

AccessScience ◽

10.1036/1097-8542.595000 ◽

2015 ◽

Keyword(s):

Rubber Tree

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Hevea Rubber Tree

Scientific American ◽

10.1038/scientificamerican01131917-23bsupp ◽

1917 ◽

Vol 83 (2141supp) ◽

pp. 23-24

Keyword(s):

Rubber Tree

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The Flowing Clotting Time (Thrombus Formation Time) a Sensitive Test of Hypercoagulability

Thrombosis and Haemostasis ◽

10.1055/s-0038-1653565 ◽

1969 ◽

Vol 21 (03) ◽

pp. 516-523

Author(s):

H Engelberg ◽

L. P Engelberg

Keyword(s):

Thrombus Formation ◽

Formation Time ◽

Sensitive Test ◽

Clotting Time ◽

Reliable Test ◽

Time Test ◽

Plasma Heparin

SummaryThe addition of small amounts of extrinsic thromboplastin or of thrombin to blood in vitro accelerated coagulation more frequently and to a greater extent when determined by the flowing time test than when measured by the silicone clotting time, or by the blood or plasma heparin tolerance tests. Similar results were obtained when intrinsic thromboplastin formation was stimulated by contact with glass. However there was little or no acceleration of the flowing clotting time of plasma obtained from aliquots of the thromboplastin-containing blood. These results indicate that the flowing clotting time (thrombus formation time) of whole blcod is a more reliable test of hypercoagulability than previously described blood or plasma clotting time tests.

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