Article

Effect of elevated CO2 and high temperature on seed-set and grain quality of rice

Division of Plant Physiology, Indian Agricultural Research Institute, New Delhi 110012, India.
Journal of Experimental Botany (Impact Factor: 5.53). 03/2012; 63(10):3843-52. DOI: 10.1093/jxb/ers077
Source: PubMed

ABSTRACT

Hybrid vigour may help overcome the negative effects of climate change in rice. A popular rice hybrid (IR75217H), a heat-tolerant check (N22), and a mega-variety (IR64) were tested for tolerance of seed-set and grain quality to high-temperature stress at anthesis at ambient and elevated [CO(2)]. Under an ambient air temperature of 29 °C (tissue temperature 28.3 °C), elevated [CO(2)] increased vegetative and reproductive growth, including seed yield in all three genotypes. Seed-set was reduced by high temperature in all three genotypes, with the hybrid and IR64 equally affected and twice as sensitive as the tolerant cultivar N22. No interaction occurred between temperature and [CO(2)] for seed-set. The hybrid had significantly more anthesed spikelets at all temperatures than IR64 and at 29 °C this resulted in a large yield advantage. At 35 °C (tissue temperature 32.9 °C) the hybrid had a higher seed yield than IR64 due to the higher spikelet number, but at 38 °C (tissue temperature 34-35 °C) there was no yield advantage. Grain gel consistency in the hybrid and IR64 was reduced by high temperatures only at elevated [CO(2)], while the percentage of broken grains increased from 10% at 29 °C to 35% at 38 °C in the hybrid. It is concluded that seed-set of hybrids is susceptible to short episodes of high temperature during anthesis, but that at intermediate tissue temperatures of 32.9 °C higher spikelet number (yield potential) of the hybrid can compensate to some extent. If the heat tolerance from N22 or other tolerant donors could be transferred into hybrids, yield could be maintained under the higher temperatures predicted with climate change.

Download full-text

Full-text

Available from: Krishna SV Jagadish
    • "A wide range in sterility incidence was documented in the dry season (1.6–67%), with the WS having <1–35.5%. The majority of previous studies have used AT to explain variability in heat stress induced spikelet sterility, while some recent studies indicate strong interactions between AT and RH, affecting plant tissue temperature (Madan et al., 2012;Yoshimoto et al., 2011;Julia and Dingkuhn, 2013). These studies identified the importance of considering the canopy or organ temperature due to large differences in the temperature recorded between air and the panicle. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Heat stress induced increase in spikelet sterility is often correlated with prevailing air temperature during anthesis. However, plant tissue temperature can be different from air temperature, depending on transpiration cooling which is a function of relative humidity (RH). Controlled environment studies involving heat stress are generally conducted at targeted RH, hence excluding the dynamics associated with this factor. Using 81 diverse indica cultivars over three years (wet season-2012, dry season-2013 and 2014), flag leaf temperature (FLT), panicle temperature (PT) and air temperature (AT) were measured during flowering under field conditions. On average the FLT and PT were 10.4 and 8.7 °C lower than AT during the wet season and were 9.9 and 8.0 °C lower when averaged across all three seasons. Spikelet sterility in dry seasons ranged between 1.6 and 67% compared to <1 and 35.5% during the wet season. Spikelet sterility was significantly correlated with PT (r = 0.50; p < 0.01) and FLT (r = 0.55; p < 0.01), compared with a weaker relationship with AT (r = 0.23; p < 0.05) among the tested 81 cultivars, pooled across both 2013 and 2014 dry seasons. By employing an unbiased Z score approach, cultivars with (i) consistent and contrasting for sterility percentage and (ii) phenology (duration from seeding till 50% flowering) based on flowering date confirmed the strong relationship between FLT or PT with spikelet sterility compared to AT. In conclusion, we recommend using either PT or FLT (tissue temperatures) instead of AT for future field based heat stress phenotyping. Where direct PT measurements are not available, mechanistic and empirical models can be used to derive PT or FLT from weather station data, or remotely sensed canopy temperature might be used as a proxy in large scale phenotyping experiments.
    No preview · Article · Oct 2015 · Field Crops Research
  • Source
    • "c o m ScienceDirect results have shown that increased [CO 2 ] would increase rice yield, as rice is a C 3 species and generally responds positively to elevated [CO 2 ] by increasing its carbon assimilation rates. In the absence of temperature rise, several studies have shown increased yields of food grains with increased [CO 2 ] [8] [9] [10]. However, despite this favorable effect, the combined increase in temperature and variation in rainfall will markedly affect food grain production. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The present experiment was conducted to evaluate the effect of elevated [CO2] with varying nutrient management on rice–rice production system. The experiment was conducted in the open field and inside open-top chambers (OTCs) of ambient [CO2] (≈390 μmol L–1) and elevated [CO2] environment (25% above ambient) during wet and dry seasons in 2011–2013 at Kharagpur, India. The nutrient management included recommended doses of N, P, and K as chemical fertilizer (CF), integration of chemical and organic sources, and application of increased (25% higher) doses of CF. The higher [CO2] level in the OTC increased aboveground biomass but marginally decreased filled grains per panicle and grain yield of rice, compared to the ambient environment. However, crop root biomass was increased significantly under elevated [CO2]. With respect to nutrient management, increasing the dose of CF increased grain yield significantly in both seasons. At the recommended dose of nutrients, integrated nutrient management was comparable to CF in the wet season, but significantly inferior in the dry season, in its effect on growth and yield of rice. The [CO2] elevation in OTC led to amarginal increase in organic C and available P content of soil, but a decrease in available N content. It was concluded that increased doses of nutrients via integration of chemical and organic sources in the wet season and chemical sources alone in the dry season will minimize the adverse effect of future climate on rice production in subtropical India.
    Full-text · Article · Oct 2015
    • "For instance, postanthesis drought can cause up to 30% decrease in yield (Borrell et al., 2000). It is also known that elevated [CO 2 ], drought, high temperature, and any combinations of these stresses can lead to significant changes in grain composition (Taub et al., 2008; Da Matta et al., 2010; Uprety et al., 2010; Madan et al., 2012), suggesting diverse metabolic alterations and/or adaptations that occur in the plant when it is cultivated in such conditions. Although the impacts of elevated [CO 2 ] and drought on photosynthesis and the growth of sorghum have been well documented (Conley et al., 2001; Ottman et al., 2001; Wall et al., 2001), no attention has been given to the impact of the combination of these two environmental changes on plant metabolism and composition . "
    [Show abstract] [Hide abstract]
    ABSTRACT: Projections indicate an elevation of the atmospheric CO2 concentration ([CO2]) concomitantly with an intensification of drought for this century, increasing the challenges to food security. On the one hand, drought is a main environmental factor responsible for decreasing crop productivity and grain quality, especially when occurring during the grain-filling stage. On the other hand, elevated [CO2] is predicted to mitigate some of the negative effects of drought. Sorghum (Sorghum bicolor L. Moench) is a C4 grass that has important economical and nutritional values in many parts of the world. Although the impact of elevated [CO2] and drought in photosynthesis and sorghum growth has been well documented, the effects of the combination of these two environmental factors on plant metabolism have yet to be determined. To address this question, sorghum plants (cv. BRS 330) were grown and monitored at ambient (400 µmol.mol-1) or elevated [CO2] (800 µmol.mol-1) for 120 days, and submitted to drought during the grain-filling stage. Leaf photosynthesis, respiration, and stomatal conductance were measured at 90 and 120 days after planting, and plant organs (leaves, culm, roots, prop roots, and grains) were harvested. Finally, biomass and intracellular metabolites were assessed for each organ. As expected, elevated [CO2] reduced the stomatal conductance, which preserved soil moisture and plant fitness under drought. Interestingly, the whole-plant metabolism was adjusted and protein content in grains was improved by 60% in sorghum grown under elevated [CO2]. Copyright © 2015, Plant Physiology.
    No preview · Article · Sep 2015 · Plant physiology
Show more