Biochemical- and productivity-related parameters for the identification of drought-tolerant materials in peanut.

GUZZO MC; COSTAMAGNA, C; SOAVE JH; SOAVE SJ; BUTELER MI; MONTEOLIVA, MI

WAshington DC

Congreso; Plant Biology Worldwide Summit; 2020

ASPB

Drought is the major constrain to peanut production in Argentina. To reduce economic losses new cultivars are being developed. Our aim is to reduce the time to identify drought-tolerant materials, compared with traditional field screening. We evaluated biochemical parameters at vegetative stages which may indicate drought-tolerance and validate drought tolerance in reproductive stages.We evaluated 6 peanut materials: Granoleico (commercial check), EC-98, JS.9499, I14-09, Pronto, and I16-02. We exposed them to drought stress when leaf 6 was emerged by water withhold until 30% of water holding capacity (WHC) (sand: soil, 1:1 v/v). We monitored several parameters (RWC, proline, sugars, chlorophylls, carotenoids). We observed variability in the response to analyzed parameters and identified two tolerant material I14-09 and I16-02.We checked if these tolerant materials I14-09 and I16-02 remained tolerant when the drought occurs at reproductive stages, as occurs in the fields in the Argentinian crop region. We withheld the pots at reproductive stages starting when all the plants had flowers (same substrate, in 4 Kg pots). The stress was maintained for one month at 30% WHC and then plants were re-watered at field capacity until the end of the cycle. Biochemical parameters were monitored during stress (proline, chlorophylls, carotenoids, sugars), and biomass and yield parameters at the end of the cycle (dry biomass, number, and weight of grains and fruits). Cultivars I14-09 and I16-02 showed higher proline, chlorophylls, carotenoids, and sugar content than the check (Granoleico) associated with no reduction in grain number and higher grain weight under stress.Altogether our results support it is possible to identify drought-tolerant materials in vegetative stages as a marker for drought tolerance in other developmental stages. Additionally, proline, chlorophylls, carotenoids, and total soluble sugars become useful traits of drought tolerance in peanut.