1. PHENOTYPING FOR ADAPTATION TO DROUGHT AND LOW-PHOSPHORUS SOILS IN COWPEA (VIGNA UNGUICULATA (L.) WALP.) Nouhoun Belko1, Ousmane Boukar1, Christian Fatokun1, Vincent Vadez2 1 International Institute of Tropical Agriculture (IITA), NIGERIA 2 International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), INDIA
Background
Conclusions
Drought and poor soil fertility are the major environmental factors limiting crops yield and food production in the semi-arid regions of Sub-Saharan Africa. Water- & phosphorus use efficiency (PUE) are hypothesized to improve crop productivity in marginal environments. Therefore, high-throughput phenotyping of relevant traits and effective breeding of improved cultivars can be a low-input approach to enhancing the resilience and sustainability of agriculture in the semi-arid tropics.
Significant genetic variability for plant performance under drought & low phosphorus conditions and potential sources of drought tolerance (Fig.1) and PUE identified (Fig. 2).
Different hypothetical plant water-use patterns in response to (i) soil drying (Fig.3) & (ii) increases in the air VPD (Fig. 4) characterized and relevant water saving shoot traits identified.
Perspectives: (i) use high-tech tools (GPR, TLS) for rapid and precise plant phenotyping and (ii) crop modeling to predict abiotic stresses effects on yields & determine the probability of specific traits success.
Objectives
Assess the genetic variability for agro-physiological plant traits conferring drought and low-phosphorus stress tolerance in cowpea.
Identify elite lines and develop new high yielding, nutritional valued, and drought and low-phosphorus adapted varieties.
NRC/
date
Results
Substantial genetic variation in water saving traits (TR, LA) important for terminal drought tolerance in cowpea (1,2).
Several cultivars identified as potential parents for improved drought, low-P tolerance and nutritional value (3,4,5).
New improved cowpea lines under release & deployment for different agro-ecological zones in sub-Saharan Africa.
Fig. 1
Extensive work / significant results in selection of P-use efficient cowpeas at IITA-Ibadan (southern Nigeria).
New screening sites at IITA-Kano (northern Nigeria) for replicated and robust data across locations.
Crop models parameterized to (i) test plant traits benefits across stress scenarios & (ii) suggest ideotypes / cropping systems vs. climate change.
Fig. 2
Methods
Cowpea plants evaluated in (a) field station, (b) lysimetric system, (c) screen-house and (d) growth chamber experiments in and
Screen-house/growth chamber
Innovative & precise phenotyping methods for plant water saving traits hypothesized to be crucial for terminal drought adaptation. Whole plant water-use patterns measured gravimetrically and by IR thermography (1).
Lysimetric-rainout shelter platform
High-throughput and accurate phenotyping for root traits, water-use, growth and yields. Identification, characterization & discussion of different plant traits of interest for use in breeding programs (1, 2).
Field experimental station
Screening cowpeas and assessing genetic variability for drought tolerance using stress tolerance indices (3,4). Analysis & selection of elite lines with improved agronomical traits and high nutritional value (5). a b c d
References:
Belko et al Functional Plant Biology
Vadez et al Functional Plant Biology
Belko et al Crop Science
Fatokun et al Plant Genetic Res.
Boukar et al Plant Genetic Res.
Acknowledgments:
Bill and Melinda Gates Foundation
Generation Challenge Programme
Contact details:
Dr. Nouhoun Belko
Nestle Agricultural Conference:
Planting Seeds for the Future of Food
Nestle Research Center, Lausanne, Switzerland, 2-3 June 2015