scholarly journals Effect of Exogenous Hormonal Stimulation on the Metabolic Partition between Plant Growth and Rubber Production of Hevea brasiliensis Clones According to the Class of Metabolic Activity in Cote d'ivoire

2021 ◽  
pp. 46-64
Author(s):  
Lehi Malidy Irénée ◽  
Konan Djezou ◽  
Okoma Koffi Mathurin ◽  
Yoboue Ange Naté ◽  
Konan Kouakou Séraphin ◽  
...  
Keyword(s):  
Metabolic Activity ◽  
Hevea Brasiliensis ◽  
Polynomial Function ◽  
Inorganic Phosphorus ◽  
Strongly Correlated ◽  
Hormonal Stimulation ◽  
Rubber Production ◽  
Good State ◽  
Growth Production ◽  
Low Sensitivity

Aims: In order to achieve a good and sustainable harvest of Hevea brasiliensis rubber, the effect of exogenous hormonal stimulation on the metabolic partition growth-production of clones according to the class of metabolic activity was made. Place and Duration of Study: The study was conducted for 9 years in the San-Pedro region in south-west Ivory Coast, precisely in the experimental industrial plantations of the former HEVEGO, now Southwestern Agricultural Civil Society Société (SCASO). Methodology and Results: The rubber trees were planted at a density of 510 trees/ha in a completely randomised system. They were bled in S/2 d4 and stimulated to 2.5% Etephon at annual frequencies of 0, 1, 2, 4, 6, 8, 13, 18, 26, 39 and 78. The parameters measured were rubber production, trunk circumference, sucrose content, inorganic phosphorus, thiol groups and dry notch rate. The results showed that productivity increased with the intensity of stimulation (58.96 - 68.49 g.a-1.s-1 ; 39.83 - 66.69 g.a-1.s-1) over the intervals [0.6] and [0.26] stimulations respectively in clones with active and slow metabolism. The circumference of the trunk was marked by a less pronounced decrease in growth in slow metabolizing clones (0.52%) with good protection of the laticigene system (R-SH : 0.815 mmol.l-1) and low sensitivity to dry notching (1.6). Whatever the classes of metabolic activity of the clones, the agrophysiological parameters were strongly correlated with each other by a degree 2 polynomial function. Conclusion: This polynomial function seems to reflect the existence of a good state of equilibrium between laticigenic metabolism and vegetative growth according to the class of metabolic activity of the Hevea brasiliensis clones.

scholarly journals Characteristic Microbiomes Correlate with Polyphosphate Accumulation of Marine Sponges in South China Sea Areas

2019 ◽  
Vol 8 (1) ◽  
pp. 63
Author(s):  
Huilong Ou ◽  
Mingyu Li ◽  
Shufei Wu ◽  
Linli Jia ◽  
Russell T. Hill ◽  
...  
Keyword(s):  
High Throughput Sequencing ◽  
Inorganic Phosphorus ◽  
Marine Sponges ◽  
Strongly Correlated ◽  
Mantel Tests ◽  
Low Concentrations ◽  
Enrichment Rate ◽  
Total Dna ◽  
Polyphosphate Accumulation ◽  
Sequence Similarities

Some sponges have been shown to accumulate abundant phosphorus in the form of polyphosphate (polyP) granules even in waters where phosphorus is present at low concentrations. But the polyP accumulation occurring in sponges and their symbiotic bacteria have been little studied. The amounts of polyP exhibited significant differences in twelve sponges from marine environments with high or low dissolved inorganic phosphorus (DIP) concentrations which were quantified by spectral analysis, even though in the same sponge genus, e.g., Mycale sp. or Callyspongia sp. PolyP enrichment rates of sponges in oligotrophic environments were far higher than those in eutrophic environments. Massive polyP granules were observed under confocal microscopy in samples from very low DIP environments. The composition of sponge symbiotic microbes was analyzed by high-throughput sequencing and the corresponding polyphosphate kinase (ppk) genes were detected. Sequence analysis revealed that in the low DIP environment, those sponges with higher polyP content and enrichment rates had relatively higher abundances of cyanobacteria. Mantel tests and canonical correspondence analysis (CCA) examined that the polyP enrichment rate was most strongly correlated with the structure of microbial communities, including genera Synechococcus, Rhodopirellula, Blastopirellula, and Rubripirellula. About 50% of ppk genes obtained from the total DNA of sponge holobionts, had above 80% amino acid sequence similarities to those sequences from Synechococcus. In general, it suggested that sponges employed differentiated strategies towards the use of phosphorus in different nutrient environments and the symbiotic Synechococcus could play a key role in accumulating polyP.

scholarly journals Latex production with depolymerizing compounds of actin cytoskeleton in rubber trees

2008 ◽  
Vol 43 (2) ◽  
pp. 275-279 ◽  
Author(s):  
Gao Zheng-Quan ◽  
Meng Chun-Xiao ◽  
Ye Nai-Hao
Keyword(s):  
Actin Cytoskeleton ◽  
Potassium Iodide ◽  
Hevea Brasiliensis ◽  
Total Solid ◽  
Inorganic Phosphorus ◽  
Latrunculin A ◽  
Tapping Panel Dryness ◽  
Latex Production

The objective of this work was to assess stimulated latex flow from rubber trees (Hevea brasiliensis) with saturated macrolide (latrunculin A), 1, 5, and 10% potassium iodide in 2% methylcellulose compared with 0.3% ethylene in 2% methylcellulose (check) and 2% methylcellulose (blank). Latex output and contents of pure rubber, total solid, sucrose, inorganic phosphorus, thiol, and Mg2+ were measured. The treatments containing 1% KI or saturated macrolide increased latex yields compared to the blank with 2% methylcellulose alone. The 1% KI or saturated macrolide treatments were equal to that of 0.3% ethylene check treatment. However, 5 and 10% KI were harmful to bark of rubber trees, even caused prolonged tapping panel dryness.

scholarly journals Protein Biomarkers in Glaucoma: A Review

2021 ◽  
Vol 10 (22) ◽  
pp. 5388
Author(s):  
Ewa Fiedorowicz ◽  
Anna Cieślińska ◽  
Patrycja Kuklo ◽  
Andrzej Grzybowski
Keyword(s):  
Open Angle Glaucoma ◽  
Strongly Correlated ◽  
Protein Biomarkers ◽  
Glaucoma Diagnosis ◽  
Early Primary ◽  
Low Sensitivity ◽  
Chemical Groups ◽  
Support Treatment ◽  
Current Screening ◽  
Reliable Testing

Glaucoma is a multifactorial disease. Early diagnosis of this disease can support treatment and reduce the effects of pathophysiological processes. A significant problem in the diagnosis of glaucoma is limited access to the tested material. Therefore, intensive research is underway to develop biomarkers for fast, noninvasive, and reliable testing. Biomarkers indicated in the formation of glaucoma include chemical compounds from different chemical groups, such as proteins, sugars, and lipids. This review summarizes our knowledge about protein and/or their protein-like derived biomarkers used for glaucoma diagnosis since 2000. The described possibilities resulting from a biomarker search may contribute to identifying a group of compounds strongly correlated with glaucoma development. Such a find would be of great importance in the diagnosis and treatment of this disorder, as current screening techniques have low sensitivity and are unable to diagnose early primary open-angle glaucoma.

scholarly journals Within-family genomic selection in rubber tree (Hevea brasiliensis) increases genetic gain for rubber production

2019 ◽  
Vol 138 ◽  
pp. 111464 ◽  
Author(s):  
David Cros ◽  
Luther Mbo-Nkoulou ◽  
Joseph Martin Bell ◽  
Jean Oum ◽  
Aurélien Masson ◽  
...  
Keyword(s):  
Genomic Selection ◽  
Genetic Gain ◽  
Hevea Brasiliensis ◽  
Rubber Tree ◽  
Rubber Production

scholarly journals Effect of Late Upward Tapping on the Productivity of the Metabolically Active Hevea brasiliensis Clone PB 260 in Southwestern Cote d'Ivoire

2021 ◽  
pp. 107-117
Author(s):  
Kouakou N’guessan Kan Pulchérie ◽  
Moro Affia Perpetue ◽  
Diarrassouba Moussa ◽  
Lehi Irénée Malydie ◽  
Konan Djézou ◽  
...  
Keyword(s):  
Cote D'ivoire ◽  
Hevea Brasiliensis ◽  
Vegetative Growth ◽  
Côte D’Ivoire ◽  
Block Design ◽  
High Yield ◽  
Physiological Profile ◽  
Rubber Production ◽  
Set Up ◽  
Société Civile

In order to evaluate the improvement of rubber productivity of rubber trees by late upward tapping. A study was conducted at SCASO (Société Civile Agricole du Sud-Ouest) on the PB 260 clone of the active metabolic class. The experimental set-up is a Fisher block design with eight treatments and three replications. The treatments compared were bled in reverse in the eleventh year of harvest, in quarter spiral every 3, 4, 5 and 6 days, with stimulation frequencies of 6, 8, 10, 12 and 13 times a year. The parameters measured were rubber production, isodiametric growth, sensitivity to dry notching of trees and physiological profile. The results show that the different latex harvesting technologies improve the rubber productivity of PB 260 (5469 kg.ha-1.yr-1) with a low dry-nut rate (1.2%) and satisfactory radial vegetative growth (3.9cm.yr-1). The physiological profile of the trees is balanced, but the treatments significantly influenced the different parameters except sucrose. Trees bled in S/4U d3 gave better results due to their high yield with an acceptable dry notch rate. Late reverse tapping is therefore a good latex harvesting technology for improving rubber productivity after down tapping.

Civilizing Latex

2018 ◽  
pp. 23-56
Author(s):  
Michitake Aso
Keyword(s):  
Nineteenth Century ◽  
Hevea Brasiliensis ◽  
Rubber Production ◽  
Environment And Health ◽  
The World ◽  
Late Nineteenth ◽  
Plantation Agriculture ◽  
National Networks ◽  
The Tropics

Rubber trees motivated the utilization, and construction, of imperial and national networks of knowledge production that linked French Indochina to France and to other colonial territories around the world. This effect placed rubber at the heart of efforts to discipline the tropics. Chapter 1 examines the introduction of hevea brasiliensis to Indochinese environments during the late nineteenth and early twentieth centuries, a process that involved laws marking the physical and intellectual boundaries between forests and plantation agriculture. It begins with a discussion of the southeast region of Vietnam and the study of nature in Indochina during the nineteenth century. New understandings of human and nonhuman natures enabled the production of commodities such as rubber, and rubber production for global consumption in turn helped reformulate the coproduction of human and nonhuman natures in local places. The chapter lays down a baseline for evaluating later transformations in environment and health as plantation agriculture replaced biological diverse habitats with much simpler ecologies.

POSSIBILITY OF EARLY COMMENCEMENT OF TAPPING IN RUBBER (HEVEA BRASILIENSIS) USING DIFFERENT GENOTYPES AND TAPPING SYSTEMS

2007 ◽  
Vol 43 (2) ◽  
pp. 201-221 ◽  
Author(s):  
H. K. L. K. GUNASEKARA ◽  
E. A. NUGAWELA ◽  
W. A. J. M. DE COSTA ◽  
D. P. S. T. G. ATTANAYAKE
Keyword(s):  
Flow Rate ◽  
Hevea Brasiliensis ◽  
Yield Components ◽  
Low Frequency ◽  
The Other ◽  
Yield Response ◽  
Rubber Content ◽  
Rubber Production ◽  
Significant Yield ◽  
Lower Stem

The feasibility of commencing tapping (‘opening’) of rubber trees for latex extraction at a lower stem girth (40 and 45 cm) than the currently recommended 50 cm was investigated in three different genotypes. The possibility of combining early opening with low frequency tapping and yield stimulation using Ethrel (LFT + E) was also examined. One of the genotypes tested, RRIC 121, gave a higher dry rubber yield, both per tapping and cumulatively over a given period, when opened at 40 cm than at 50 cm. Of the other two genotypes, one (RRISL 211) showed a clear reduction in yield with early opening, while the other (RRIC 102) did not show a significant yield response. Among the three genotypes tested, RRIC 121 showed the minimum depression in trunk girth increment. Analysis of yield components showed that the response of a given genotype to early opening and LFT + E is determined by the interaction between latex volume per tapping and dry rubber content (DRC), which were negatively correlated. RRIC 121 had a significantly greater DRC, which enabled it to maintain a higher dry rubber yield under early opening and LFT + E despite producing a lower latex volume than both the other genotypes. In contrast, despite producing a substantially greater latex volume than the other two genotypes, RRISL 211 did not produce a higher dry rubber yield because of its lower DRC. The higher DRC was also responsible for the greater response of RRIC 121 to yield stimulation with Ethrel, which reduced the plugging index and increased the initial latex flow rate. Early commencement of tapping in combination with LFT + E is therefore possible in rubber when amenable genotypes are selected, offering the potential of improving the economics of rubber production, especially for smallholders, in West Asia.

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