PrintSend to friend
Concurrent Session VII : RICE AND CLIMATE CHANGE
Chairman : Dr. P. Subbian
Co-Chairman : Dr. S. Jeyaraman
Rapporteurs : Dr. C. Vijayalakshmi and Dr. A. Velayutham
Lecture 1 : Intercultivation in rice by Dr. T. M. Thiyagarajan
Intercultivation is crucial for the first time at 10-12 DAT in SRI and Intercultivation - manipulation of soils, water and air effectively increase the microbial activity.
Under SRI, nutrient dynamics improved by intercultivation resulting in crop growth and increased grain yield. Hand weeding along with inter cultivation improves the yield of rice as well and saves 64 hr labour hours and the numbers of laboures required for weeding. Herbicides are not recommended in SRI. Intercultivation improves new root growth, due to decomposition of organic matter.
Lecture 2 : "Sustaining rice production under changing climate : A case study in
Cauvery basin" by Dr.V.Geethalakshmi
Rice crop is largely expected to be impacted by changing climatic condition. Future climate projections indicate increase in temperature by 1.5O C in the middle of the century and 3.0 to 3.5oC by the end of the century with more rainfall but in short spells and with more intensity. Extreme weather events like persistent drought and flash floods frequency is also increasing. Rice crop in the Cauvery basin would go down by 25 to 30%, if not, adaption measures are taken up in the warmer condition. Two adaptation and mitigation technologies identified are climate resilient agriculture based on the expected weather (forecast) and tailoring the management technologies. Altering the social window, inclusion of Azolla and Cyanobacteria, integrated nutrient management and Promotion of SRI are suggested.
Lecture 3 : "Employing physiological and molecular strategies to address heat and drought tolerance at flowering in rice" by Dr. Jagadish Krishna, IRRI
Genetic diversity for high night temperature tolerance testing, identifying more number of novel sources of early morning flowering and intro gressing heat tolerance into heat susceptible major varieties combining heat and drought tolerance are suggested in this context. Physiological and molecular mechanisms for combined heat and drought tolerance need to be understood well for
effective crop improvement.
Lecture 4 : "An innovative approach to mitigate green house gas emissions from paddy farming" by Dr. Gurbir Singh Bhullar, ETH, Switzerland
The author has presented that Methane emission has doubled since 1750 and a shift in species composition of a wetland ecosystem may result in important feed back mechanism due to changes in green house gas emissions. Further it was explained that Greenhouse gases especially methane are lower when different species of plants are present. An alternative approach ie. intercropping of rice with another plant species viz., aquatic vegetables ( Chinese water chestnut ) to reduce methane gas emission in particular and over all green house gases in general and midseason drainage to reduce the methane emission by 50% have been suggested.
Lecture 5 : "Apoplastic assimilates: an indicator for filling capacity of rice grain" by Dr. P.K. Mahapatra
It was explained that heterogeneous panicle architecture is a liability for grain filling. Ethylene is negatively correlated with cell division and grain filling activities and apoplastic movement of assimilates is controlled by maternal parent
Lecture 6 : "SRI enhances water productivity in rice" by Dr. B.J. Pandian
Enhancement of water productivity to the tune of 7.30 kg ha-1 mm-1 in SRI compared to 4.51 kg ha-1 mm-1 under conventional method in the farmers holding of Tamil Nadu was brought out by this study. According to him, the virtual water content for SRI is 1398 lit for 1kg whereas it was 2274 lit for 1 kg under conventional method, thereby effecting 40% saving of water.
Lecture 7 : "Integrated weed management techniques with brown manuring at different levels of N under direct seeded aerobic rice" by Seema.
She found that application of 100kg N/ha is found to be advantageous for aerobic rice along with brown manuring of weeds with application of pre-emergence herbicides
Lecture 8 : "Foliar silicic acid technology for rice: a new safe healthy and efficient method for the growth of rice" by Dr. Henk-Maarten Laane, the Netherlands
This study indicated that rice yield increased from 5000 to 6380 kg/ha due to the combined application of silicic and boric acid. Silicic acid is not a fertilizer but a plant growth promoter and it
is easy to apply, cost effective, safe and eco-friendly.
Lecture 9 : "Carbon sequestration pattern in SRI and conventional method of rice cultivation" by Dr. K.S. Subramanian
It was brought out that SRI cultivation assists in carbon sequestration by reducing methane emission to the atmosphere while accumulating glomalin in soil. The intense biological activity associated with SRI favours passive carbon pool.
X Inter cultivation is crucial for the first time at 10-12 DAT in SRI