HRPP Annual Seminar 2016

The 7th Annual Seminar of the HRPP was held from Tuesday, November 15th to Thursday, November 17th, 2016 at Kasetsart University, Bangkhen Campus, Bangkok. Cirad was the host.

The first two days were devoted to scientific presentations in plenary session, workshops and roundtables to assess and update the scientific program of the HRPP.

The third day was devoted to two specific workshops related to ongoing and prospective projects, according to propositions from the members.


- Introduction of HRPP by Assoc. Prof. Dr. Sornprach Thanisawanyangkura, Acting Vice-President for Planning of Kasetsart University, President of the HRPP
- Introduction of the program by Dr. Philippe Thaler, CIRAD, Coordinator of the HRPP

Scientific Presentations

1 Philippe Thaler, Cirad, Current context and challenges for HRPP scientists

2 Bénédicte Chambon, Cirad, Structure of rubber farms. Corporate farms in Thai rubber sector?

3 Songpol Tippayawong, TFT, Building Resilience of rubber farmers in Surat Thani

4 Pierre-Marie Bosc, Cirad, Institutional analysis of share-tapping contracts in smallholder rubber farms in Thailand

5 Thongchai Sainoi, PSU, Assessment of Low Frequency Tapping Systems with Stimulation on Young-tapping Hevea in Southern Thailand

6 Yuwadee Samila, KKU, The use of ethylene stimulation to enhancing the rubber tapping

7 Narissara Puangjumpa, KKU, Water use of 5 immature rubber clones under well-watered condition

8 Rungtawan Thabkhun, KU, Study on Leaf Photosynthesis Rate and Water Use Efficiency of 5 Rubber Clones

9 Chompunut Chayawat, KU, Study on carbon and water balance to estimate carbon footprint and water footprint of rubber plantation

10 Stefanie Goldberg, ICRAF, Greenhouse gas emissions in rubber plantations

11 Jate Sathornkich, KU, 13C field labeling of full rubber trees to track carbon from assimilation to latex

12 Supat Isarangkool Na Ayutthaya, KKU, Development of leaf nutrient standard in Northeast Thailand

13 Alexis Thoumazeau, Cirad, BIOFUNCTOOL: An in-field package to assess soil quality based on soil functioning

14 Phantip Panklang, PSU, Impact of three rubber agroforestry systems on soil functionalities and diversity

15 Pusanisa Heepngoen, KU, Dynamics of litter degradation and soil fauna assemblage along a chronosequence of rubber plantations

16 Frédéric Gay, Cirad, Fertility and fertilization issues in rubber plantations: new insights from recent research works

17 Laurent Vaysse, Cirad, Fertilization and quality of natural rubber

18 Bénedicte Chambon, Cirad, Farmers post-harvest practices

19 Céline Bottier, Cirad, Impact of ammonia-stabilization and storage time on biochemical and physicochemical indicators of latex

20 Siriluck Liengprayoon, KU, Lipid composition of latex centrifugation fractions

21 Jatuporn Chaiyut, KU, Physical properties of NR made from various combinations of latex centrifugation fractions

22 Kanthida Wadeesirisak, KU, Rubber particle proteins REF1 and SRPP1 interact differently with native lipids extracted from Hevea brasiliensis latex

23 Patrick Rousset, Cirad, Low cost activated carbon: A solution to manage waste water odour at collecting points?

The perspectives and evolution of HRPP – Discussion sessions with panels

1 - Managing soil cover, the key for sustainability of plantations

Introduction by F Gay, Cirad
Panel: JL Janeau(IRD), (KU), Supat I.N. Ayutthaya (KKU), P Malagoli (UBP)

2 - Low prices and lack of manpower, what can we do now?

Introduction by Jessada Sopharat, PSU
Panel: Regis Lacote (CIRAD), M Keaney Yara, Pisamai Chantuma (RAOT)

3- The future of Thai NR: towards an observatory of the chain from farm to factory

Introduction by PM Bosc (CIRAD)
Panel: Poonpipope Kasemsap (KU)

4 - The use of isotope methodologies in NR science

Introduction by P Thaler (CIRAD)
Panel : Poonpipope Kasemsap (KU), P Malagoli (UBP), L Vaysse (CIRAD), Jessada Sopharat (PSU)

Multidisciplinary workshops in parallel session

1 -The building-up of quality from the farm to the factory gate
2- On-going and future projects using isotope methodologies


Where Does The Latex Carbon Come From?

World first 13C Labeling of field-grown rubber trees

One of the main challenges for the future of Natural Rubber production is the scarcity of skilled manpower to tap the trees. The only way to cope with such issue is to reduce the tapping frequency. The key is the carbon supply to the latex producing tissues. With low tapping frequencies, the latex exported at each tapping day is higher than in traditional systems. Then the trees must mobilize huge amount of carbon at each tapping. Does the latex carbon come directly from the primary sources, the leaves where C is assimilated through photosynthesis, or from reserve pools as wood starch, or both? Knowing the actual C sources and knowing the pathways towards latex is necessary to manage the tapping systems.

Stable isotopes and especially 13C are widely used in plant science as tracers. A team from Kasetsart University, RAOT, CIRAD and Université de Lorraine realized the first field labeling of full crowns of tapped rubber trees with 13CO2 to trace the carbon from its assimilation in the leaves to the tree sinks and particularly to latex. Such experiment, using a specifically designed chamber, has never been done so far on rubber trees. Three trees (RRIT 408) were labelled in June 2016 and three others in October at the Chachoengsao Rubber Research Center. We sampled leaves, phloem, wood and latex to analyze their 13C content and determine the dynamics of carbon allocation from leaves to reserves and to latex. The latex samples will be followed during one year. The first results are expected at the end of 2016.

The labelling operation was the support of a program on CO2 cycle in rubber plantations broadcasted by TV9, a public Thai channel, on Sunday 4, September. You can stream the program (in Thai language, except the interviews of foreign scientists) here.

The team

Kasetsart University: Ornuma Duangngam, Poonpipope Kasemsap, Jate Sathornkich, Chompunut Chayawat, Duangrat Satakhun
Cirad: Philippe Thaler
Université de Lorraine: Daniel Epron, Pierrick Priault, Dorine Desalme
Université de Paris Sud : Jaleh Ghashghaie
RAOT : Pisamai Chantuma