Intercropping with two native woody shrubs improves water status and development of interplanted groundnut and pearl millet in the Sahel
To investigate the physiological responses of groundnut (Arachis hypogea) and pearl millet (Penisetum glaucum) that were intercropped with the native evergreen woody shrubs Piliostigma reticulatum (D.C.) Hochst and Guiera senegalensis J.F. Gmel compared to control crops throughout two growing seasons at two sites with contrasting climate and soil types in Senegal.
Shrubs grown in groundnut and millet fields at higher than native density were coppiced annually with aboveground biomass returned to the soil and no additional fertilizer. Crop leaf area index (LAI), handheld normalized difference vegetation index (NDVI), leaf water potential, and soil moisture and temperature were monitored in 2012–2013.
At the drier site, the presence of shrubs reduced soil temperature at 5 cm depth by up to 5 °C during early crop growth. Shrub presence increased LAI by up to 266%, NDVI by up to 217% and increased groundnut leaf water potential throughout the day at the wetter site. Shrub effects on crop physiology were stronger overall at the drier site.
These results improve the understanding of how this unique agroforestry system alters the growing environment and the physiological response of associated crops throughout the season.
KeywordsAgroforestry Agroecology Abiotic stress Soil hydrology Plant physiology
The US National Science Foundation Partnerships for International Research and Education (PIRE) grant (NSF #0968247) funded this work. Additional funding was given by UC Merced. We are thankful to Mame Balla Ndiaye and Boubacar Badji for collecting data and Dame Sy all transportation and communication with local farmers. Yacine Ndour and Lydie Lardie of ISRA and IRD, respectively, coordinated lab space. Mohammed Safeeq as well as the Berhe Biogeochemistry lab at UC Merced provided valuable feedback on early versions of this manuscript.
Compliance with ethical standards
Conflict of interest
We are not aware of any conflicts of interest.
- Badiane AN, Khouma M, Sène M (2000) Région de Diourbel: Gestion des eaux. Drylands Research, CrewkerneGoogle Scholar
- Barnabás B, Jäger K, Fehèr A (2008) The effect of drought and heat stress on reproductive processes in cereals. Plant Cell Environ 31(1):11–38Google Scholar
- Diack M, Sène M, Badiane AN, Diatta M, Dick RP (2000) Decomposition of a native shrub, Piliostigma reticulatum, litter in soils in semiarid Senegal. Arid Soil Res Rehab 14:205–218Google Scholar
- Diedhiou-Sall S, Dossa EL, Diedhiou I, Badiane AN, Assigbetse KB, Samba SAN, Khouma M, Sene M, Dick RP, Assigbetse KB, Samba N, Arona S, Khouma M, Sène M, Dick RP (2013) Microbiology and macrofaunal activity in soil beneath shrub canopies during residue decomposition in agroecosystems of the Sahel. Soil Sci Soc Am J 77(2):501–511CrossRefGoogle Scholar
- FAO (2015) Food and Agricultural Organization of the United Nations Statistical Database. Technical report, RomeGoogle Scholar
- Google Inc. (2016). Google earth (version 220.127.116.1102) [computer software]. Available from https://www.google.com/earth/. Accessed 15 September 2016
- Hernandez RR, Debenport SJ, Leewis MCCE, Ndoye F, Nkenmogne KIE, Soumare A, Thuita M, Gueye M, Miambi E, Chapuis-Lardy L, Diedhiou I, Dick RP (2015) The native shrub, Piliostigma reticulatum, as an ecological “resource island” for mango trees in the Sahel. Agric Ecosyst Environ 204:51–61CrossRefGoogle Scholar
- Horton R, Wierenga PJ, Nielsen DR (1983) Evaluation of methods for determining the apparent thermal diffusivity of soil near the Surface1. Soil Sci Soc Am J 47(1):–25Google Scholar
- Huda AKS, Sivakumar MVK, Alagarswamy G, Virmani SM, Vanderlip RL (1984) Problems and prospects in modeling pearl millet growth and development: a suggested framework for a millet model. Agrometeorol of Sorghum Millet Semi-Arid Trop, pp 297–306Google Scholar
- Jackson RD, Kirkham D (1958) Method of measurement of the real thermal diffusivity of moist soil. Soil Sci Soc Am J 22(6):–479Google Scholar
- Kizito F, Sène M, Dragila M, Lufafa A, Diedhiou I, Dossa E, Cuenca R, Selker J, Dick R, Sene M, Dragila M, Lufafa A, Diedhiou I, Dossa E, Cuenca R, Selker J, Dick R (2007) Soil water balance of annual crop native shrub systems in Senegal’s Peanut Basin: the missing link. Agric Water Manag 90(1–2):137–148CrossRefGoogle Scholar
- Kroener E, Zarebanadkouki M, Kaestner A, Carminati A (2014) Nonequilibrium water dynamics in the rhizosphere: How mucilage affects water flow in soils. Water Resour Res 50:6479–6495. https://doi.org/10.1002/2013WR014756
- Mahalingam R (2014) Combined stresses in plants: physiological, molecular, and biochemical aspects. Springer, New YorkGoogle Scholar
- Maiti RK, Bidinger FR (1981) Growth and development of the pearl millet plant. Research bulletin no. 6. Technical report, International Crops Research Institute for the Semi-Arid TropicsGoogle Scholar
- Michéli E, Schad P, Spaargaren O (2006) World reference base for soil resources 2006: a framework for international classification, correlation and communication. Food and agriculture organization of the united nations (FAO), RomeGoogle Scholar
- Peacock JM (1982) Response and tolerance of sorghum to temperature stress. Technical report, International Crops Research lnstltute for the Semi-Arid Tropics, PatancheruGoogle Scholar
- R Core Team (2016) R: A Language and Environment for Statistical ComputingGoogle Scholar
- Renaud L (1961) Le Precambrien du sud-ouest de la Mauritanie et du Senegal oriental. PhD thesis, ParisGoogle Scholar
- Sharma H, Shukla MK, Bosland PW, Steiner R (2017) Soil moisture sensor calibration, actual evapotranspiration, and crop coefficients for drip irrigated greenhouse chile peppers. Agric Water Manag 179:81–91Google Scholar
- United Nations (2014) 2014-2016 strategic response plan Sahel region. Technical report January, United Nations Office for the Coordination of Humanitarian Affairs (OCHA)Google Scholar
- USDA (2015) Crop values: 2014 summary. Technical Report February, United States Department of AgricultureGoogle Scholar
- Vanlauwe B, Wendt J, Diels J (2001) Combined application of organic matter and fertilizer. In: Sustaining Soil Fertility in West Africa, (sustainingsoilf), pp. 247–280Google Scholar