If some one can specifically comment about the best strategies to increase photosynthetic efficiency. In my view one of the possible approach is to enhance the turnover rate of PSII protein (D1 and D2).

There are many possible strategies, including altering the efficiency of Rubisco or Rubisco activase, reducing photorespiration or reducing the negative effect of sugar accumulation. You can even find some attempts to modify plant architecture in order to increase light harvesting.

You might find this paper quite interesting, since they mention several strategies that in development to increase photosynthetic efficiency and ultimately, crop yields... hope it helps: http://naldc.nal.usda.gov/download/26792/PDF

Dear friend

Attached file may be useful

Dear Rakesh

Your question: "What are the possible strategies to increase photosynthetic efficiency?", call my attention.

May be we have many ways to get a better efficiency for the photosynthetic process. I'll propose two:

a) If the colour of plants can be associated to the spent energy to separate negatives from positives charges on leaves, we should go to a red shift colour to waste less energy than the green colour we have today. Note that the photosynthesis process is a physical mechanism, mainly based on charges separation. The charges movements on leaves, after the photons absorptions, proposed on books violate physical laws (e.g., going from a molecule to the neaby molecule, without having the action af an electric field).

b) Increasing the CO2 concentration you can get better efficiency, as proposed in this publication (60% more biomass and 25% more sugar for sugar cane plants exposed to double CO2 concentration. Please, see these publications:

1- A. P. de Souza, M. Gaspar, E. A. da Silva, E. C. Ulian, A.

J. Waclawovsky, M. Y. Nishiyama Jr., R. V. dos Santos,

M. M. Teixeira, G. M. Souza and M. S. Buckeridge,

“Elevated CO2 Increases Photosynthesis, Biomass and

Productivity, and Modifies Gene Expression in Sugarcane,”

Plant, Cell & Environment, Vol. 31, No. 8, 2008,

pp. 1116-1127. doi:10.1111/j.1365-3040.2008.01822.x

2- A. P. de Souza and M. S. Buckeridge, “Photosynthesis in

Sugarcane and Its Strategic Importance to Face the Global

Climatic Change,” In: Cortez LAB, Ed., Sugarcane Bioethanol:

R & D for Productivity and Sustainability, Edgard

Blucher, São Paulo, 2010, pp. 320-323.

Dear Sacilotti :), You say that the higher Co2 content, better efficiency in photosynthesis. Is there any misundertanding between greenhouse effect in which they addressed high CO2 atmospehere and plant vegetation affeceted adversely....

Dear Buhara Yucesan

There are many controversies about green house effect. One of these controversies is: may be the global temperature is decreasing (and not increasing), as stated by experimental measurements on deep seas. Many others controversies appears, e.g.: as a physicist how can I accept the effect of sun light absorption by CO2 (400 ppm on Earth), compared to about 78% of N2 and of O2? Thermodynamically it is impossible that absorption for 0,0004% of CO2 could be higher than the absorption for about 100% of N2 plus O2. Earth's physical parameters are cyclical and not permanent and its temperatures changes from time to time. The same happens with CO2 concentration. Only Nature produces 97% of CO2 on Earth. There is no sense in discussing on decreasing 30% of 3%. A vulcano (like Pinatubo) do more green hose effect than man in 2 centuries. The Tokio and Rio meeting on green house effect has been a 'fiasco' and people are opening their yes now. Oceans control many of the physical parameter on Earth. Man do very litle. Of course, we should decrease pollution but not with the non "scientific" exposed proofs we have today.

Experimental results show that 2 billions of years ago we have had about 10% of CO2. Life started at that time, followed by big forests (CO2 = to many food for plants) . Today, with 400 ppm, ours small forests are not enough feeded and, so, the desertification process takes place. By the way, in my opinion, we should increase CO2 concentration on Earth, to decrease the desertification effect we are having today.

Increasing photosynthetic efficiency is not a simple task, because it's depends of many different aspects. Also depends of our point of view, ranging from the thylakoids to plant communities, and the final use of plants (e.g. grains, wood). One interesting possible strategy to artificially increase photosynthetic capacity could be that proposed in this work: Kebeish, R., Niessen, M., Thiruveedhi, K., Bari, R., Hirsch, H.-J., Rosenkranz, R., Stabler, N., Schonfeld, B., Kreuzaler, F. and Peterhansel, C. (2007) Chloroplastic photorespiratory bypass increases photosynthesis and biomass production in Arabidopsis thaliana. Nat. Biotechnol., 25, 593-599.

Photosynthetically , there are 4 types of plants; C4, C3, CAM and C3- C4 intermediates. C4 is considered to be more efficient. But majority of crop plants belong to C3. The C3 RuBPCase , the universal carbon fixing enzyme, is the most inefficient enzyme and it has specity for both CO2 and O2 . Lot of research been done on knocking out O2 affinity but it failed to do the job of exacerbating photosynthesis. In fact, oxygenase activity is much needed for C3 to protect against photo xidative damage. Even through genetic engineering it is impossible to improve the photosynthetic efficiency of the plants

There is some publication which prove that it is possible to increase photosynthetic efficiency some of the publication mention above. But now the important point is to even small increase in photosynthetic efficiency is not beneficial for cereals. In future we need more food to fulfill the demands of growing population. This will very challenging task for the photosynthetic scientist to think about the strategies which reflects in the form of yield, even 5-10 % but we need to start to think seriously.......

Dear all.There is a product called Agrostemin www,agrostemin.com .

Originally was developed based on the phenomenom of allelopathy,which as we know

results in positive or negative synergy between plants,even within the same spicies.

Through the years of application and observation,one of the basic reactions of all plants

is the increase of chlorophyl and photosynthesis,and as an end result we get higher

yields,higher protein or aminoacid content,higher oil,higher sugar and higher fiber.

If you need more info or questions contact [email protected]

Dear Abhishek Raj, what is described in the first two abstracts that to provided, is exactly what takes place when applying Agrostemin. No need to alter any genes or to induce in the existing ones. A comment that I got regarding a potato cultivar, was "why the leaves have a different shape?" That comment says a lot. The increase in both chlorophyll a and b, as well as the increase in dry matter and yield, provides the answer, without getting into technical details.