Table 1. Potential for producing insect-resistant or fungal disease-resistant
transgenic rice plants
_______________________________________________________________________________
Desired New Trait* Target Insect or Potentially Useful Genes for
Fungus Transforming Rice
_______________________________________________________________________________
Insect Resistance Yellow stemborer; Genes encoding protease inhibitors:
Striped stemborer; CpTi,PinII,SbTi; B.T. genes:
Rice leaffolder cryIA(b),cryIA(c); RIP
Gall midge cryIII,PinII, RIP genes
Brown planthopper; GNA gene, RIP genes
Green leaffolder
Fungal Disease R.solani (causative agent of Genes encoding chitinases,
Resistance sheath blight);P.oryzae (causa- Beta-1,3-glucanases, RIPs,
tive agent ot rice blast) thionins, and antifungal peptides
_______________________________________________________________________________
*New traits in transgenic rice plants that can be produced via biotechnology.
More recently, a second survey, made by R. E. Evenson (1994), has
identified five components of the rice biotechnology program. Two of these
components, insect resistance and disease resistance, are briefly summarized
in this report. These two components have been chosen because more facts are
available for them and because these traits are usually controlled by single
genes. Thus, they are more amenable to manipulation by applying
biotechnology. These and other traits have formed a significant part of
conventional rice breeding strategies over the past 20 years. This close
parallel between the RF program design and conventional breeding has been
used by R. E. Evenson in his assessment analysis and economic evaluation
(1994), which are briefly summarized as follows.Table 2 summarizes both optimistic and conservative estimates of the time required to conclude field trials of transgenic rice plants. Conservative estimates of the time required for the transgenic rice plants to reach farmer's fields are also included. As can be seen from Table 2, the optimistic estimate of the time required to achieve field trials of insect-resistant plants is six years from 1994, and the conservative estimate is 8-10 years.
Table 3 summarizes the estimates of the expected economic payoff as a result of successfully producing field-tested, insect-resistant and disease-resistant trans-
Table 2. Estimated time to produce useful transgenic rice plants by
biotechnology
_______________________________________________________________________________
Optimistica Conservativea Conservativeb
Desired New Trait (Field Trials) (Field Trials) (Used by Farmers)
_______________________________________________________________________________
Insect resistancec 6 8-10 12-15
Disease resistancec 6 10-15 12-18
_______________________________________________________________________________
a. Estimated time (in years) from 1994 to the time for field trials.
b. Estimated time (in years) from 1994 to the time for farmers to grow
the transgenic rice plants in the field.
c. Transgenic rice harboring a single insect-resistant gene or a single
disease-resistant gene.
Table 3. Estimates of effects or benefits of the rice biotechnology programs
_______________________________________________________________________________
Time to Productiona
(Years) Annual Effect or Benefit After Realization
Trait or Yield_________________________________________________________________
Enhancement Opti- Conser- Areab Yieldc Quantityd Valuee
(million (billion
mistic vative (M ha) (%) tons) dollars)
_______________________________________________________________________________
Multiple insect
resistancef 12 21 37 30 41 8.0
Multiple disease
resistanceg 15 22 50 15 27 5.4
Total Annual
Benefit 13.4
_______________________________________________________________________________
a. Estimated time from 1994 to the time to production.
b. Area estimated based on incremental areas (in million hectares) to
conventional breeding.
c. Estimated increase of yield bawd on India-Indonesia studies of R.E.
Evenson (1994).
d. Increase in yield of rice in million tons.
e. Value in 1990 dollars.
f. Transgenic rice plants harboring several insect-resistant genes. It
would take 6-11 years longer to produce transgenic plants of this
type than are required to produce plants harboring a single
insect-resistant gene, as shown in Table 1.
g. Trangenic rice plants harboring several disease-resistant genes.
genic rice plants. As can be seen, the estimated annual benefit of using
insect- resistant and disease-resistant transgenic rice plants in farmer's
fields is 13.4 billion dollars. The benefit is expected to start around the
year 2012 (the mid point between the optimistic and conservative estimates).
If other biotechnolo- gy-based improvements, such as stress tolerance and
general yield enhancement, are included (not shown in Table 3, but shown in
Evenson's report), the estimated annual benefit will amount to over 30
billion dollars (Evenson 1994). Considering the fact that the Rockefeller
Foundation's investment in the rice biotechnology program between 1985 and
1994 was around 60 million dollars (The RF 1993 Annual Report, p.11), and
assuming that the support by the RF between 1995-2012 will be 240 million
dollars, the total investment would be approximately 300 million dollars.
The total financial support for rice biotechnology programs from all other
sources between now and the year 2012 have been estimated to be close to 2.4
billion dollars. Thus, the projected annual benefit, starting from the year
2012, would be five times (13.4/2.7) larger than the total estimated support
by RF and other sources between 1985 and 2012. A different way of
calculating the annual benefit/cost ratio after the year 2012 is to divide
$13.4 billion (total annual benefit) by $0.15 billion (estimated annual
investment after the year 2012), which gives 90 as the benefit/cost ratio.References
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