caa a22 4500 477110800 CHVBK 20180405111608.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF00035053 doi (NATIONALLICENCE)springer-10.1007/BF00035053 Drought-avoidant soybean germplasm maintains nitrogen-fixation capacity under water stress [Elektronische Daten] [Robert Patterson, Colleen Hudak] Inoculated soybeans (Glycine max L. (Merrill)) were grown in controlled environments to evaluate the relationship between genotype and plant water status on nodule function, nitrogen assimilation, growth rates, and seed yield. Plants were grown under well-watered (WW) and water-stressed (WS) conditions during the linear pod-filling growth stage in sand culture using N-free nutrient solution. Dry matter and N accumulation were greater for the drought-adapted Plant Introduction 416937 (PI) than for ‘Forrest', a commercially adapted genotype of similar phenology. These differences are attributed to: (i) more favorable internal water balance throughout the pod-filling period (higher total leaf water potential), (ii) higher photosynthetic function (more total leaf area and higher net carbon exchange rates), and (iii) stronger nodule function (larger nodule mass, greater specific and total nodule activity, and thus more nitrogen assimilation) for the PI than for Forrest. While Forrest out yielded the PI under WW conditions, the percentage reduction in seed mass per plant was less for the PI than for Forrest when both genotypes were exposed to desiccating conditions. The inference is that soybean germplasm with the capacity to maintain tissue turgidity, and thus leaf and nodule function, during reproductively-imposed desiccation may reduce the extent to which yield is compromised during drought. These findings have implications for the role of symbiotic nitrogen fixation in conserving yield under dry weather conditions. Kluwer Academic Publishers, 1996 acetylene reduction nationallicence drought nationallicence drought-avoidant germplasm nationallicence Glycine max (L.) Merrill nationallicence growth nationallicence nitrogen nationallicence assimilation nationallicence DAE : Days After Emergence nationallicence NCE : Net CO2 Exchange nationallicence PI : PI 416937 nationallicence SNA : Specific Nodule Activity nationallicence TNA : Total Nodule Activity nationallicence WS : Water Stressed nationallicence WW : Well Watered nationallicence Patterson Robert Department of Crop Science, N.C. State University, P.O. Box 7620, 27695, Raleigh, NC, USA aut Hudak Colleen Department of Crop Science, N.C. State University, P.O. Box 7620, 27695, Raleigh, NC, USA aut Plant and Soil Kluwer Academic Publishers; http://www.wkap.nl 186/1(1996-09-01), 39-43 0032-079X 186:1<39 1996 186 11104 https://doi.org/10.1007/BF00035053 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00035053 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Patterson Robert Department of Crop Science, N.C. State University, P.O. Box 7620, 27695, Raleigh, NC, USA aut NATIONALLICENCE 700 1- Hudak Colleen Department of Crop Science, N.C. State University, P.O. Box 7620, 27695, Raleigh, NC, USA aut NATIONALLICENCE 773 0- Plant and Soil Kluwer Academic Publishers; http://www.wkap.nl/ 186/1(1996-09-01), 39-43 0032-079X 186:1<39 1996 186 11104 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer