Researchers identified promising breeding lines that exhibit tolerance to drought and heat stress that will pave way to the development of new varieties that addresses climate change in the country’s major rice-growing areas.
Thelma Padolina, lead researcher of the study entitled, “Screening of rice-induced mutants for heat and drought tolerance,” presented at the 23rd Federation of Crop Science Societies of the Philippines, Inc. Scientific Conference in Clark Zone, Pampanga last month, said although rice normally grows at temperatures between 20 and 35°C, it is at its most sensitive during the booting and flowering stages. Hence, even short-duration chronic dry spells occurring during these stages will result in substantial yield loss.
Padolina and her team started the series of screening in 2012 where 817 mutant lines were initially screened for drought stress and leaf blast, and later with emphasis to heat stress. Mutant lines are valuable genetic variations for crop improvement. They are the results of induced mutation where one or two of their major traits, for instance plant height and resistance to biotic and abiotic stresses, were altered.
The researchers said promising lines were exposed to temperatures ranging from 21.1°C to 34.4°C at field trials, and 34°C to 38°C at screenhouse trials for 3 consecutive seasons to test and validate their grain fertility and pollen viability.
On the other hand, the Philippine Rice Research Institute (PhilRice) has produced an information kit to equip farmers with information on how they can better adapt to the impacts of climate change.
Said info kit is a “ready-to-print” material that contains a list of climate change-ready technologies the farmers can use for rice and rice-based farming systems. It includes the recommended varieties that can withstand different climate-related stresses such as drought, salinity, and flood.
For water-saving technologies, PhilRice recommends the alternate wetting and drying (AWD) and low-cost drip irrigation system (LDIS) technologies.
AWD guides farmers when to irrigate (or not) the rice field. Hence, this prevents wasteful use of water. PhilRice studies show that use of AWD also minimizes greenhouse gas emissions in paddy fields.
LDIS is also for efficient use of water and is recommended for irrigating rice-based crops. Meanwhile, fossil fuel-free technologies such as the rice hull gasifier-pump system, windmill- pump system, rice hull stove, and carbonizer are also featured. The rice hull gasifier-pump system uses rice hull instead of gasoline or diesel in pumping water from the ground. It is recommended for rainfed areas where fuel expenses are high. The wind mill-pump system is applicable in areas where wind energy is abundant.
A device called rice hull carbonizer is for processing the rice hull into biochar (charcoal). Aside from being used as soil conditioner, biochar is also popularly used as main ingredient in producing organic fertilizers thus reducing dependence on synthetic fertilizers.
Additionally, the kit also features Palayamanan Plus, an integrated and diversified farming system, and some harvest and postharvest technologies. Farmers, extension workers, or anyone interested may download the kit from the PhilRice website.