Variation in Expression of <i>Sub</i>1 Gene and Association with Submergence Stress Related Traits in Advance Rice (<i>Oryza sativa</i> L.) Genotypes as a Tool of Climate Change Adaptation

Abstract

Floods have now become most detrimental natural catastrophe worldwide due to radical climatic fluxes. Therefore, there is a dire necessity to develop a high yielding rice lines to deal with this scenario. For this purpose, a large scale experiment was conducted including one hundred and fifteen (115) rice genotypes having SUB1 gene imported from International Rice Research Institute (IRRI) Philippines, six local cultivars/approved varieties and three high yielding rice varieties i.e. Sabitri, IR6 and NSICRC222 being used as potential varieties in different countries of Asia as susceptible check and IR64-SUB1 as tolerant check. The genotypic screening was performed using two PCR-based DNA markers i.e. ART5 and SC3. Phenotypic screening was conducted in a natural pond to assess the interaction of SUB1 gene in natural stagnant flood water as well as the suitability of introgression of SUB1 gene into approved varieties and elite rice lines. The genotypes were assessed in terms of plant survival percentage, submergence tolerance index, physical condition, stem elongation, number of grains per panicle, thousand grain weight, grain yields and deviations in these traits after submergence stress. The PCR results suggested that both the primers ART5 and SC3 may be used as potential PCR-based markers for molecular screening of rice genotypes for SUB1 QTL. Furthermore, it confirmed the presence of SUB1 gene in all the lines imported from IRRI, while it was absent in all the local cultivars studied. All the genotypes with submergence tolerant gene (SUB1) showed significantly greater tolerance level in submergence stress of 14 days, as compared to other local cul-

Responses of Four Submergence Tolerant Rice Varieties to Different Submergence Levels

“…A decreasing trend in effective tillers hill -1 was shown by all the varieties as the duration of submergence increased. The formation of tiller bud might hamper due to submergence and it might cause a reduction of effective tillers hill -1 (Fukao et al, 2006;Haider et al, 2018). The lack of oxygen for respiration or accumulation of ethylene might inhibit tiller bud formation and growth.…”

Productivity and Agronomic Efficiency of Inundation Tolerance Rice in the Swampland: A Review

“…The problem of inundation in swamps, especially in the freshwater wetland, will be more severe if there is erratic rainfall due to global climate change. Inundation will occur if rainfall increases both in intensity and frequency [14,15]. The plant will sink if the rainfall conditions are above average (La Nina).…”

Agronomic and economic study of the application of some rice cropping systems in irrigation rice land

“…One study found that this system can increase production by 20% [15,16], while another study found that this system can increase plant population and lowland rice production by 33.07% compared to the conventional system [17,18]. Meanwhile, variety-related climate change mitigation and adaptation measures include the development of early-maturing, drought-tolerant [19], submergence-resistant [20] and salinity-tolerant rice cultivars. This study summarizes research findings on the application of several rice cropping systems with climate change-adaptive improved cultivars.…”