Water uptake dynamics under progressive drought stress in diverse accessions of the OryzaSNP panel of rice (Oryza sativa)

Abstract

In addition to characterising root architecture, evaluating root water uptake ability is important for understanding drought response. A series of three lysimeter studies were conducted using the OryzaSNP panel, which consists of 20 diverse rice (Oryza sativa L.) genotypes. Large genotypic differences in drought response were observed in this genotype panel in terms of plant growth and water uptake. Total water uptake and daily water uptake rates in the droughtstress treatment were correlated with root length density, especially at depths below 30 cm. Patterns of water uptake among genotypes remained consistent throughout the stress treatments: genotypes that initially extracted more water were the same genotypes that extracted more water at the end of the study. These results suggest that response to drought by deep root growth, rather than a conservative soil water pattern, seems to be important for lowland rice. Genotypes in the O. sativa type aus group showed some of the greatest water uptake and root growth values. Since the OryzaSNP panel has been genotyped in detail with SNP markers, we expect that these results will be useful for understanding the genetics of rice root growth and function for water uptake in response to drought.

Genotypic variation in soil water use and root distribution and their implications for drought tolerance in chickpea

“…These changes were (i) early reduction or check in root prolificacy in surface soils most likely due to the early death of ultimate branches, (ii) greater prolificacy of roots in soil depths below 30 cm, and to a much greater extent below 75 cm, thereby increasing the proportion of deeper soil roots (Lafitte et al 2001;Mishra et al 2001;Comas et al 2005;Benjamin and Nielsen 2006;Guswa 2008;Henry et al 2011), (iii) reduction in overall root biomass (Robertson et al 1980;Sánchez-Blanco et al 2002;dos Santos et al 2007;Navarro et al 2009;Álvarez et al 2009, 2011, (iv) reduction in root thickness, thereby increase in root length within the available root biomass, and to explore more volume of soil (Bañon et al 2003;Koike et al 2003;Kulkarni and Deshpande 2007;Chylinski et al 2007;Franco et al 2008;De Sousa and Lima 2010;Álvarez et al 2011;Wasson et al 2012;Bandyopadhyay 2014) and (v) early senescence of root system matching the shoot system senescence with no relevance to soil water availability. Similar pattern of RLD distribution was also observed in several legumes and cereal species such as field pea, rice, canola, cowpea, sunflower and sorghum (Liu et al 2011;Gowda et al 2012;Cutforth et al 2013;Moroke et al 2005).…”

“…Efficient water uptake ability was found to be essential for yield improvement (Fischer et al 1998;Blum 2009;Wasson et al 2012) and this efficiency is recognised to rely on the size and activity of the root system (Gregory 1994;Gowda et al 2012). Timely and enhanced soil water uptake by equally large root systems seems to be one of the most promising approaches for enhancing drought tolerance in legumes and this association was documented in many studies (Kamoshita et al 2000;Okada et al 2002;Kashiwagi et al 2006Kashiwagi et al , 2015Bernier et al 2009;Bandyopadhyay 2014).…”

Effets de six composts sur les réponses physiologiques, biochimiques et agronomiques du niébé <i>Vigna unguiculata</i> L. Walp var. KVX. 61.1. au déficit hydrique

“…Ces résultats concordent avec ceux rapportés par Werner et al (2010), Gowda et al (2012), et Vadez et al (2012b qui ont suggéré que l'augmentation de la croissance des racines en profondeur en condition de déficit hydrique améliore l'absorption de l'eau des plantes afin de maintenir un taux maximal de croissance aérienne. Cette réduction pourrait aussi résulter, en partie, de l'effet des restrictions imposées au système racinaire par le volume limité des pots.…”

Breeding for Drought Resistance Using Whole Plant Architecture — Conventional and Molecular Approach

“…Two in field (WW and drought) and one in PVC tubes. The selection was based on all three traits: Good Roots + Shoots + Grain yield [21]. …”