Table 5.

Evaluation of different field devices for genotype study/screening in response to drought.

Field devices for drought study	Cost	Strengths	Limitations	Suitable climate and soils	Reference
Late planting with drainage in rainy season trial	Large uniform field management	High chance of reproductive and terminal drought	Photoperiod non-sensitive	Semi-arid tropics	Pantuwan et al. (2002a)
Dry-season trial	Large uniform field management	High chance of drought, vegetative drought	Photoperiod non-sensitive, genotype-by-season interaction	Semi-arid tropics	Pantuwan et al. (2004)
Line-source sprinkler	Equipment, water source, monitoring	Different water regimes	Wind, space	Semi-arid to arid climate	Garrity and O’Toole (1994)
Rainout shelter	Construction	All types of drought	Space, cost		Lilley and Fukai (1994)
Greenhouse	Construction	All types of drought	Space, cost, rhizosphere differences (small and loose)		Yadav et al. (1997), Wade et al. (2000)
Root restriction	Rhizosphere manipulation	Evaluation of non-root traitsa	Space	Hardpan, simulated lowland	Kato et al. (2007)
Raised bed	Rhizosphere manipulation	Dry surface soil (interrupt capillary water)	Space	Sub-humid climate	Kato et al. (2007)

(Source: Kamoshita et al., 2008).

^aRestriction of the root zone removes the advantage of deep rooted varieties that would be expressed if no restriction; in most puddled lowland fields roots are restricted.