Top Indian Rice Geneticist Rebuts SRI Critics
Dr. A Satyanarayana responds to criticisms of SRI as someone responsible for introducing the practice to the Andhra Pradesh state of India.
I read the news feature "Rice cultivation: feast or famine" in Nature (25 March 2004) with great interest as I was responsible for introducing the System of Rice Intensification (SRI) in the Indian state of Andhra Pradesh since the kharif (summer) season of 2003.
I found the message conveyed by the article not quite balanced. The experiences of farmers are very different from what is said by sceptical scientists. Instead of trying to understand how a rice plant can respond differently under an SRI environment, they are confused about the potential of SRI, giving information based on rice cultivation under flooded conditions that are definitely not SRI practice.
Having worked as a plant geneticist for over 3 decades on the genetic improvement of leguminous crops under rice-based cropping systems, I have released 34 varieties of various grain legumes that are widely adopted in rice-pulse or rice- rice-pulse cropping systems covering over one million hectares in the state. I have been responsible, from 1995 to 2000, for research in the Krishna and Godavari deltas, which, with 1.5 million ha of rice-growing area, are known as the rice bowl of Andhra Pradesh. At present, I am Director of Extension for the state agricultural university (ANGRAU) and transfer of technology is my job. So, I do know about the rice crop.
In January 2003, I was able to learn about SRI on a study tour to Sri Lanka, and was amazed to see the potential of this system. On returning to Andhra Pradesh, I started educating farmers on the skills involved in SRI and motivated them to take up this system on a small scale in demonstration plots. We planned to organise 50 demonstrations through ANGRAU's extension service and 150 through the State Department of Agriculture. But more than 300 farmers took up SRI during the summer season of 2003.
On average, the size of the demonstration plot was 0.4 ha, with the largest at 1.6ha. As many as 10 different varieties, chosen by the farmers themselves, were tried in all 22 districts of the state, under different soil and irrigation systems. The results achieved were highly satisfactory, giving an average yield advantage of over 2.0 t/ha. About 40 farmers got yields over 10t/ha, and 5 districts had average yields over 10t/ha. The highest recorded was 16.2 t/ha followed by 15.7t/ha.
The average over all the demonstration plots was 8.36t/ha compared to 4.9 t/ha with conventional practice and the state average of 3.89t/ha. These yields are not theoretical. They were properly recorded after thorough drying. On seeing the performance of this system, many farmers volunteered to practice SRI during the current winter season on more than 5 000 acres in the state.
Many farmers used SRI on over 10 acres. One farmer (Mr. N. V. R. K. Raju) practiced SRI on over 100 acres (40ha.), and an average yield of more than 10 t/ha is expected. I request sceptics to visit Andhra Pradesh and see SRI in practice before drawing conclusions.
Under SRI, the rice crop is maturing 10 days earlier than with usual cultivation practices, irrespective of the variety, which is contrary to what was stated in the Nature news feature, that SRI takes two weeks longer to mature. Also, SRI required less water and less chemical inputs. SRI gave higher grain as well as straw yield. Moreover, the SRI rice crop has withstood cyclonic gales and a cold spell.
It is unfortunate to say in the headlines of the news feature that proponents call SRI a "miracle". No one has ever said this because SRI results are quite explainable. Planting young seedlings carefully and at wider spacing gives the plant more time and space for tillering and root growth. Careful water management keeping the field wet and not flooded gives better yield because it supports healthy root growth. This practice should be encouraged everywhere as the whole world is facing water shortages. Weeding rice fields with a rotary weeder helps by churning the soil and incorporating the weed biomass as it aerates the root zone. This encourages the soil microorganisms to proliferate and makes the soil living and healthy. All of these practices are known to agronomists, and there is nothing new or magical.
The productivity of SRI as a function of input is very high, which is more important now as the Green Revolution technologies are showing fatigue. SRI has the potential to give higher yields at lower costs. Even when the farmers were unable to practice all the aspects the first season, just planting young seedlings carefully at wider spacing with somewhat better water management resulted in over 2.0t/ha extra yield compared to conventional methods using higher inputs. With more experience and mastering of skills, still higher yields are possible, as those obtained by the best farmers clearly suggest.
Rice yields all over the world have leveled out under the present system of flooded cultivation. Genotype x environment interactions are known to affect the plants' phenotype and performance. We need to be looking for alternatives to the present costly practices with an open mind. SRI is still evolving with the innovations of the farmers making implements and practices more labour-saving.
There is more than enough evidence accumulated here and elsewhere for scientists to take SRI seriously. I hope that the scientific community will collaborate in further research. Possibly it can refine the technology and reveal the factors responsible for the higher productivity observed. That would be more constructive and more in the spirit of science than dismissing it with limited or faulty data and preconceptions.
The author is Director of Extension, Acharya N. G. Ranga Agricultural University, Hyderabad-500030, Andhra Pradesh, India, and this article is adapted from his response to the Nature news feature mentioned.
http://www.i-sis.org.uk/TIRGRSRI.php
I read the news feature "Rice cultivation: feast or famine" in Nature (25 March 2004) with great interest as I was responsible for introducing the System of Rice Intensification (SRI) in the Indian state of Andhra Pradesh since the kharif (summer) season of 2003.
I found the message conveyed by the article not quite balanced. The experiences of farmers are very different from what is said by sceptical scientists. Instead of trying to understand how a rice plant can respond differently under an SRI environment, they are confused about the potential of SRI, giving information based on rice cultivation under flooded conditions that are definitely not SRI practice.
Having worked as a plant geneticist for over 3 decades on the genetic improvement of leguminous crops under rice-based cropping systems, I have released 34 varieties of various grain legumes that are widely adopted in rice-pulse or rice- rice-pulse cropping systems covering over one million hectares in the state. I have been responsible, from 1995 to 2000, for research in the Krishna and Godavari deltas, which, with 1.5 million ha of rice-growing area, are known as the rice bowl of Andhra Pradesh. At present, I am Director of Extension for the state agricultural university (ANGRAU) and transfer of technology is my job. So, I do know about the rice crop.
In January 2003, I was able to learn about SRI on a study tour to Sri Lanka, and was amazed to see the potential of this system. On returning to Andhra Pradesh, I started educating farmers on the skills involved in SRI and motivated them to take up this system on a small scale in demonstration plots. We planned to organise 50 demonstrations through ANGRAU's extension service and 150 through the State Department of Agriculture. But more than 300 farmers took up SRI during the summer season of 2003.
On average, the size of the demonstration plot was 0.4 ha, with the largest at 1.6ha. As many as 10 different varieties, chosen by the farmers themselves, were tried in all 22 districts of the state, under different soil and irrigation systems. The results achieved were highly satisfactory, giving an average yield advantage of over 2.0 t/ha. About 40 farmers got yields over 10t/ha, and 5 districts had average yields over 10t/ha. The highest recorded was 16.2 t/ha followed by 15.7t/ha.
The average over all the demonstration plots was 8.36t/ha compared to 4.9 t/ha with conventional practice and the state average of 3.89t/ha. These yields are not theoretical. They were properly recorded after thorough drying. On seeing the performance of this system, many farmers volunteered to practice SRI during the current winter season on more than 5 000 acres in the state.
Many farmers used SRI on over 10 acres. One farmer (Mr. N. V. R. K. Raju) practiced SRI on over 100 acres (40ha.), and an average yield of more than 10 t/ha is expected. I request sceptics to visit Andhra Pradesh and see SRI in practice before drawing conclusions.
Under SRI, the rice crop is maturing 10 days earlier than with usual cultivation practices, irrespective of the variety, which is contrary to what was stated in the Nature news feature, that SRI takes two weeks longer to mature. Also, SRI required less water and less chemical inputs. SRI gave higher grain as well as straw yield. Moreover, the SRI rice crop has withstood cyclonic gales and a cold spell.
It is unfortunate to say in the headlines of the news feature that proponents call SRI a "miracle". No one has ever said this because SRI results are quite explainable. Planting young seedlings carefully and at wider spacing gives the plant more time and space for tillering and root growth. Careful water management keeping the field wet and not flooded gives better yield because it supports healthy root growth. This practice should be encouraged everywhere as the whole world is facing water shortages. Weeding rice fields with a rotary weeder helps by churning the soil and incorporating the weed biomass as it aerates the root zone. This encourages the soil microorganisms to proliferate and makes the soil living and healthy. All of these practices are known to agronomists, and there is nothing new or magical.
The productivity of SRI as a function of input is very high, which is more important now as the Green Revolution technologies are showing fatigue. SRI has the potential to give higher yields at lower costs. Even when the farmers were unable to practice all the aspects the first season, just planting young seedlings carefully at wider spacing with somewhat better water management resulted in over 2.0t/ha extra yield compared to conventional methods using higher inputs. With more experience and mastering of skills, still higher yields are possible, as those obtained by the best farmers clearly suggest.
Rice yields all over the world have leveled out under the present system of flooded cultivation. Genotype x environment interactions are known to affect the plants' phenotype and performance. We need to be looking for alternatives to the present costly practices with an open mind. SRI is still evolving with the innovations of the farmers making implements and practices more labour-saving.
There is more than enough evidence accumulated here and elsewhere for scientists to take SRI seriously. I hope that the scientific community will collaborate in further research. Possibly it can refine the technology and reveal the factors responsible for the higher productivity observed. That would be more constructive and more in the spirit of science than dismissing it with limited or faulty data and preconceptions.
The author is Director of Extension, Acharya N. G. Ranga Agricultural University, Hyderabad-500030, Andhra Pradesh, India, and this article is adapted from his response to the Nature news feature mentioned.
http://www.i-sis.org.uk/TIRGRSRI.php
Starmail - 5. Jul, 17:37
