Soybean yield under field drought and heat: a multiscale approach

CARRERA, C.S.; SOLÍS S.M.; FERRUCCI M.S.; GALATI B.G.; TALEISNIK E.; ERGO V.V.; ANDRADE F.H.; VEGA C.C.R.; LASCANO R.H.

Hong Kong

Simposio; WUN Symposium cum Research Summit on Impacts of Grain Legume Research and Development in Developing Countries; 2017

SKL Centre for Soybean Research, The Chinese University of Hong Kong (CSR)

Water stress (WS) combined with heat stress (HS) will be important characteristics of future climate scenarios, yet there are limited studies elucidating their impact on soybean, and even less under field conditions. A holistic multiscale approach including leaf morpho-anatomical and physiological variables assessed under field conditions highlighted underlying mechanisms involved in explaining soybean yield reduction under the complex scenario of climate change.In this study, canopy temperature depression (CTD) was chosen as an integrative variable since it has been widely reported as a selection criterion to improve adaptation to drought and heat stress in crop breeding programs. Both, alterations in leaf morpho-anatomy and photosynthesis impairment can occur under stress conditions, thus, limiting yield. A field experiment was conducted to examine the association between soybean yield and several leaf physiological and morpho-anatomical traits under HS and WS during seed filling. WS alone, or combined with HS resulted in significant yield reductions (~40%) due to drops in seed number (SN) and seed weight (SW). Irrigated HS plots also showed reduced yield (19%), but SW was not affected. CTD correlated positively with yield (R²=0.67; p