[For further information on the Electronic Forum on Biotechnology in Food and Agriculture see the Forum website.
Note, participants are assumed to be speaking on their own behalf, unless they state otherwise.]

-----Original Message-----
From: Biotech-Mod2
Sent: 14 March 2007 11:02
To: 'biotech-room2@mailserv.fao.org'
Subject: 28: Focus on virtual water and green water

This is from Dr. Junguo Liu, researcher in the Department of System Analysis, Integrated Assessment and Modelling, Swiss Federal Institute of Aquatic Science and Technology (Eawag), Switzerland. My research focuses on global water scarcity and the implication of virtual water trade.

I would like to address two issues: virtual water and green water.

1. The concept of virtual water was first raised by a British scholar, Tony Allan. Allan defines the amount of water consumed in the production process of a product as virtual water. For example, to produce 1 kg of wheat, it takes approximately 1 m3 of water. When 1 kg of wheat is traded, virtually, 1 m3 of water is transfered from one country to another. This amount of 1 m3 of water is called virtual water.

S.K.T. Nasar mentioned the concept of virtual water (see message 1). However, he associated virtual water with 'embedded water'. The association is, in my opinion, incorrect. For example, the moisture content of wheat is around 14%. That means there is 0.14 kg of water embedded in 1 kg of wheat. This amount of water is not called virtual water by definition. [My understanding of S.K.T. Nasar's point was not that he was equating embedded with virtual water, but that he was suggesting that apart from the issue of 'virtual water and food trade', discussed in Section 3c) of the Background Document, there was also the issue of 'embedded water' to be considered (where e.g. the embedded water could carry unwanted contaminants, thus having potential sanitary and phytosanitary implications)...Moderator].

Many dry countries are importing enormous virtual water from the international food market. Good examples are those countries located in the Middle East and North Africa (MENA). During 1998-2002, Israel imported over 600 m3/cap/year of virtual water from crop trade, while it only used about 50 m3/cap/year of domestic water to produce crops. Virtual water import is the most direct way to compensate for the lack of domestic water resources, when the national economic situation permits it. Meanwhile, virtual water enlarges the boundary of water resources managment. A country should keep the virtual water strategy in mind when considering its water management, especially agricultural water management.

2. Water resources can be divided into green and blue water. Green water refers to the water that comes from precipitation and is stored in the unsaturated soil. Green water is typically taken up by plants as evapotranspiration. Blue water is the water in rivers, lakes, reservoirs, ponds and aquifers. Dryland production only uses green water, while irrigated production uses blue water in addition to green water.

In the past, water policies have been focused on the management of blue water resources. Massive blue water related infrastructures, such as dams, aqueducts, and pipelines, have been constructed. Agriculture investments in many countries, particularly in developing countries, were made to optimize irrigation. Blue water needs to transported to the fields and is therefore more expensive considering the construction and maintenance costs of infrastructure, let alone the often negative environmental impacts of irrigation. Many poor countries are depending increasingly on blue water, particularly in Asia and Africa and traditional large-infrastructure solutions have become less attractive, largely due to the significant increase in the construction costs.

Green water management has often been marginalized by water resources planners, who are largely engineers. However, green water plays a vital role in global food production and food trade. With a GEPIC model, we estimated global consumptive water use and the green water proportion for crop production with a spatial resolution of 30 arc-minutes. It was estimated that green water accounts for over 80% of the consumptive water use for crop production. Almost 90% of the virtual water traded among countries has its origin in green water. [A GEPIC model integrates a crop growth model, EPIC, with a geographic information system (GIS)...Moderator].

To strengthen green water management, the following issues should be widely discussed, which may be elaborated on in our e-conference.

a. strengthening rainfall management including rain water harvesting
b. Mulching in order to reduce evaporation, therefore reduce the green water consumption
c. Biotechnology. For example, a hybrid New Rice for Africa (NERICA), which has bred to grow in the uplands of West Africa, produces more than 50% more grain than current varieties when cultivated in traditional rainfed systems without fertilizer.

Dr. Junguo Liu
Swiss Federal Institute of Aquatic Science and Technology (Eawag)
Ueberlandstrasse 133
P.O.Box 611
CH-8600 Duebendorf
Switzerland
Phone: 0041-18235012
Fax: 0041-18235375
Email: water21water (at) yahoo.com

[1. Discussion of these kinds of issues is encouraged, but participants are requested to ensure that their messages also address the potential role/impact/importance etc. of agricultural biotechnologies, which is the focus of this e-mail conference. 2. New Rice for Africa (NERICA) varieties were developed using embryo rescue and anther culture techniques - see www.warda.org for more details...Moderator].

-----Original Message-----
From: Biotech-Mod2
Sent: 14 March 2007 13:42
To: 'biotech-room2@mailserv.fao.org'
Subject: 29: About the GEPIC model

This is Junguo Liu again. This message aims at explaining the GEPIC model, which is mentioned in my last message (nr. 28) but not clear to the audience.

The GEPIC model is a geographic information system (GIS) based crop growth model designed to simulate the spatial and temporal dynamics of the major processes of the soil-crop-atmosphere-management system. This model was developed in Eawag (Swiss Federal Institute of Aquatic Science and Technology). By integrating a crop growth model EPIC (Environmental Policy Integrated Climate, originally known as Erosion Productivity Impact Calculator) with a GIS system, this model can be used to simulate crop yield, crop water consumption, nutrient cycle etc on different scales (global, national, river basin, field) with high spatial resolutions.

Currently the GEPIC model has been used to simulate crop yield, evapotranspiration, and crop water productivity (a few researchers call this "water use efficiency") for 17 major crops (barley, cassava, cotton, groundnuts, maize, millet, potatoes, rapeseed, rice, rye, sorghum, soybeans, sugar cane, sugar beets, sunflower, wheat, and pulses) on the global scale with a spatial resolution of 30 arc-minutes.

The impacts of biotechnology on crop production can potentially be analyzed with the GEPIC model. The model has a crop parameter files, which can be changed for different crop varieties.

Details about the GEPIC model can be find in the following two scientific papers.

Dr. Junguo Liu
Swiss Federal Institute of Aquatic Science and Technology (Eawag)
Ueberlandstrasse 133
P.O.Box 611
CH-8600 Duebendorf
Switzerland
Phone: 0041-18235012
Fax: 0041-18235375
Email: water21water (at) yahoo.com

-----Original Message-----
From: Biotech-Mod2
Sent: 14 March 2007 17:53
To: 'biotech-room2@mailserv.fao.org'
Subject: 30: Re: Ectomycorrhiza

Responding to Message 13 by N. Manikanda Boopathi about mycorrhiza:

Myself and my student, now Prof. R. Narayanan, in your Department, have worked on Pinus patula innoculated with Pisolithus tinctorius. To combat the dumping off disease of the said plants at an early stage,i.e. at nursery, we used different doses of Captan as well as PCNB (Pentachloronitrobenzene), which are complex chemical compounds that are used as fungicides. Captan at normal dose was not only effective but also did not leave a problem with persistence in the soil. The dumping off disease of the pinus plant seedlings is observed at the ealy stage of nursery at a site specific place viz. Sandynallah (Western Ghat Mountain of India). It is a fungal disease, if it is not properly treated the plant is ultimately killed. [According to Zamuner et al (2005): "Pisolithus tinctorius (Basidiomycete) is commonly found in nature forming ectomycorrhizas, mainly with Pinus and Eucalyptus trees, in tropical and sub-tropical countries. This ectomycorrhizal fungus is commercially important since its basidiospore inoculum may be used to facilitate creation of artificial forest. The mycorrizal formation in the host root depends strongly of the P. tinctorius strains used. In this kind of symbiotic association, colonization is effective only among those high compatible plant-fungus interactions, resulting in benefits for the development of both organisms" (http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532005000500028) ...Moderator].

Dr. A.K. Bhattacharyya, Professor (Retired)
School Of Environmental Sciences
Jawaharlal Nehru University
New Delhi - 110067
India
(Address for Correspondence)
Pocket 40/5
Chittaranjan Park
P.O. New Delhi -110019
India
Tel No. 91-11-26293550
Mobile : 91-9871655840
asimjnu (at) yahoo.co.in