No body is selecting for desiccation tolerance in wheat and barley in  south east Asia, I have not come across any report of loss of viability under normal storage condition  

As far as I know Ellis and Roberts (quite likely in 1982) published comprehensive information on effect of seed dessiccation on longevity of orthodox seeded plants. In the mean time IBPGR (later IPGRI and finally Bioversity Int) published a series of books on "seed storage behaviors" in seed banks. To my level of knowledge seed dessiccation is totally related with starch or oil content of the seed. It is not supposed to be a geneticly controlled characteristic. Moisture content of seeds do equilibriate at certain level in given environmentl conditions which is called "equilibrium moisture content (EMC)". Time required for seeds to come to EMC is related with the amount of air flow in the seed lot. Many of the IBPGR publications are available in internet.

Regards

Alptekin Karagöz

I have screened since more than 10 years during my Ph D for the inheritance and molecular mapping of genes for post anthesis drought tolerance in wheat. at

Thesis: The Inheritance and Molecular Mapping of Genes for Post-anthesis Drought Tolerance (PADT) in Wheat

Khaled F M Salem

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Article: Identification and mapping quantitative trait loci for stem reserve mobilisation in wheat ( Triticum aestivum L.)

Khaled F M Salem, Marion S. Röder, Andreas Börner

[Show abstract]

Cereal Research Communications 01/2007; 35(3):1367-1374. · 0.55 Impact Factor

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Conference Paper: Molecular mapping of quantitative trait loci (QTLs) determining post-anthesis drought tolerance in hexaploid wheat (Triticum aestivum L.).

Conference Paper: Plant genetic resources- a prerequisite for drought tolerance breeding in wheat.

Börner A., S. Landjeva, K. F. M. Salem, B. KOBILJSKI, K. NEUMANN

[Show abstract]

Tagungsband 60. Tagung der Vereinigung Pflanzenzüchter und Saatgutkaufleute, Österreichs, Gumpenstein, Österreich,; 11/2009

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Stem-reserve mobilization. annual wheat newsletter 2002

Desiccation tolerance trait in orthodox seeds like wheat and barley is not a particular trait of interest to for genetic selection, because this is a general characteristics of all orthodox seeds. It may however be relevant in establishing seed priming treatment protocols, when flash drying of imbibed seeds may be necessary before seed planting or storage after priming treatments. Most publications on survival curves of orthodox seeds support the theory of a point inflection (the so-called low seed moisture limit) when drying no longer increase seed longevity, but this has not been extensively studied at varietal level. Perhaps a study looking at genotype differences in low seed moisture limits for extended longevity may elucidate desiccation tolerance variability in orthodox seeds