跳至主要内容

Dry Weight Accumulation, Root Plasticity, and Stomatal Conductance in Rice (Oryza sativa L.) Varieties under Drought Stress and Re-Watering Conditions

In rain-fed ecosystems, drought is the major obstacle to rice production. Developing varieties resistant to drought is considered a promising approach to increase rice yields in drought-prone environments. However, this approach requires an understanding of rice plant responses to drought and the mechanisms of drought tolerance in rice.

In this study, the authors conducted a pot experiment to explore growth characteristics, root plasticity, and stomatal conductance in six rice varieties (DA8, Malagkit Pirurutong, Thierno Bande, Pate Blanc MN1, Kinandang Patong, and Moroberekan) in response to different drought stress and re-watering conditions. The experiment was performed in a greenhouse at the Faculty of Agriculture, Kyushu University, Japan (33˚37'N, 130˚25'E; 3 m above sea level) in summer 2015. And the experiment was conducted in a randomized complete block design with three replicates.

The results indicated that drought stress significantly depressed plant growth, root size, and stomatal conductance in all experimental varieties. These negative effects depended on both the variety and the severity of the drought stress treatment. Under moderate drought stress (10 days after drought treatment), growth was less influenced in roots than in shoots. In contrast, there was an opposite trend under severe drought stress (15 days after drought treatment), with growth being more severely affected in roots than in shoots. Rice plants recovered from drought stress in terms of dry matter accumulation, root size, and stomatal conductance after re-watering; however, the recovery pattern differed among varieties.

In conclusion, DA8 exhibited the highest dry weight accumulation and root size (root length, root surface area, root volume, fine root length, and thick root length) under well-watered, drought stress, and re-watering conditions. Kinandang Patong showed the highest recovery ability in dry matter accumulation, root length, root surface area, and stomatal conductance after re-watering. Malagkit Pirurutong expressed the poorest recovery ability in dry matter accumulation after re-watering. These three varieties might be selected for further experiments focusing on the mechanisms of drought tolerance and recovery ability in rice.

Article by Doan Cong Dien, et al, from Kyushu University, Fukuoka, Japan.

Full access: http://mrw.so/1zXIgm

Image by Ahmad Fuad Morad, from Flickr-cc.

评论

此博客中的热门博文

Does Immigration Promote the Investment of the Monopolistic Firm?

In the present paper, we examine the effect of increasing uncertainty of immigrants’ growth on the optimal timing of investment of a firm that has a monopolistic power over the labor market. It is revealed that when the uncertainty of immigrants’ growth is more than a threshold level, increasing uncertainty of immigrants’ growth accelerates the optimal timing of firms’ investment and enhances the economic growth, even if the uncertainty of immigrants’ growth is formulated by the geometric Brownian motion, which is in sharp contrast to the standard result that an increase in the uncertainty postpones the optimal timing. With an increase in the immigrants over the past ten years, workforces in the host countries have been growing significantly to the extent that the immigrants represent 70% of the increase in the workforce in Europe, and 47% in the United States as OECD indicates. In the present paper, we attempted to investigate the effect of increased uncertainty caused by the growi...

Education Policy Implementation: A Mechanism for Enhancing Primary Education Development in Zanzibar

Education is one of the fundamental rights of individuals; therefore, the government of a country needs to develop and strengthen educational policy and quality as well as to ensure that everyone has equal access to basic education. The improvement of access and quality of education in the world is becoming as an essential factor in development, whereas the basic education (primary school), is acknowledged as a foundation of the higher educational development for every country. To fulfill this goal, governments introduce several policies and procedures; however, it requires some reforms and participation from the politician, policymakers, and other stakeholders to re-examine educational policy so that it can lead to multiplication and betterment of the reforms. Educational reforms actually focus on accountability. A positive educational development and reform is very challenging and needs more effort and strategy on how to use and utilize the resources effectively as such it can achie...