Further evidence that a terminal drought tolerance QTL of pearl millet is associated with reduced salt uptake

Sharma, P C and Singh, D and Sehene, C and Singh, G and Hash, C T and Yadav, R S (2014) Further evidence that a terminal drought tolerance QTL of pearl millet is associated with reduced salt uptake. Environmental and Experimental Botany, 102. pp. 48-57. ISSN 0098-8472

[img]
Preview
PDF (Author pay open access) - Published Version
Download (1MB) | Preview

Abstract

Earlier, we established that a major drought tolerance QTL on linkage group 2 of pearl millet is also associated with reduced salt uptake and enhanced growth under salt stress. Present study was undertaken to re-assess the performance of drought tolerant (PRLT 2/89-33) and drought sensitive (H 77/833-2) parents along with two QTL-NILs (ICMR 01029 and ICMR 01040), under salinity stress specifically imposed during post-flowering growth stages when plants had developed their ion sinks in full. Time course changes in ionic accumulation and their compartmentalization in different plant parts was studied, specifically to monitor and capture changes conferred by the two alleles at this QTL, at small intervals. Amongst different plant parts, higher accumulation of toxic ion Na+ was recorded in roots. Further, the Na+ concentration in roots of the testcross hybrid of the drought-sensitive parent (H 77/833-2) reached its maximum at ECiw 15 dS m-1 within 24 h after salinity imposition, whereas it continued to increase with time in the testcross hybrids of the drought tolerant parent PRLT 2/89-33 as well as those of its QTL-NILs (ICMR 01029 and ICMR 01004) and reached at its maximum at 120 h stage. Comparison of differential distribution of toxic ions in individual leaves revealed that Na+ ions were not uniformly distributed in the leaves of the drought- tolerant parent and drought -tolerant QTL-NILs; but accumulated preferentially in the older leaves, whereas the hybrid of the drought-sensitive parent showed significantly higher Na+ concentration in all main stem leaves irrespective of their age. Dynamics of chlorophyll and proline concentration variation studied under salt stress at late flowering stages revealed a greater reduction, almost twice, in both leaf chlorophyll and proline concentrations in younger leaves in the hybrids of the sensitive parent as compared to the tolerant parent and QTL NILs. Imposition of salinity stress even at flowering stage affected the yield performance in pearl millet, wherein higher yield was recorded in drought tolerant parent and the two QTL-NILs compared to drought sensitive parent.

Item Type: Article
Divisions: RP-Dryland Cereals
CRP: CGIAR Research Program on Dryland Cereals
Uncontrolled Keywords: Pearl millet; drought and salt tolerance; terminal drought tolerance; QTL-NILs; ionic accumulation; ionic compartmentation
Subjects: Mandate crops > Millets > Pearl Millet
Depositing User: Mr Siva Shankar
Date Deposited: 28 Feb 2014 11:35
Last Modified: 19 Oct 2016 09:19
URI: http://oar.icrisat.org/id/eprint/7571
Official URL: http://dx.doi.org/10.1016/j.envexpbot.2014.01.013
Projects: Collaborative Project with Scientists & Technologists of Indian Origin Abroad” (CPSTIO)
Funders: Department of Science and Technology (DST), Government of India - DST/INT/CP-STIO/2006-07/60/2006
Acknowledgement: The work reported in this study was conducted under “Col-laborative Project with Scientists & Technologists of Indian OriginAbroad” (CP-STIO) award to P.C.S. and R.S.Y. by the Departmentof Science and Technology (DST), Government of India. Financialsupport provided by the DST via grant number DST/INT/CP-STIO/2006-07/60/2006 is gratefully acknowledged. Plant materialsused in the study was generated in a separate project funded by theBiotechnology and Biological Sciences Research Council (BBSRC)and Department for International Development (DFID) to R.S.Y. viagrant number BB/F004133/1.
Links:

Actions (login required)

View Item View Item