We introduced our innovative field experiments in a previous blog. The aim of this part of the BiZiFED project is to determine the value of adding zinc fertilizers to wheat production in Pakistan, both in terms of yield and the potential health benefits from increasing the zinc concentration in the grain of the wheat used to make roti or chapatti.
Crop development specialists at HarvestPlus increased the zinc concentration of the wheat grain using conventional plant breeding techniques – known as genetic biofortification. We are investigating how much further the zinc concentration of the wheat grain can be increased through the application of zinc fertilizers – known as agronomic biofortification.
Three sites in Pakistan were selected based on the contrasting plant-available zinc status of their soils – high, medium and low. Replicated plots of biofortified wheat (Zincol-2016 variety) and a local reference variety of wheat were sown at each site in November 2017, using appropriate randomised designs.
Eight different zinc fertilizer treatments were applied to the wheat crop, including basal applications (to the soil) and foliar applications (to the leaves) in various concentrations, and at various growth stages of the crop.
Treatment plots at each site were coded with simple numbering before recording crop growth parameters. Crop traits were recorded at maturity from randomly selected plants at each site, including plant height, number of tillers per square metre, spike length, number of grains per spike, and weight of grains per spike.
The field team encountered several challenges during the growing period. Heavy rainfall and hail storms caused some damage to the crop and delayed the harvest. This also affected data collection because some of the wheat was ‘lodged’ or flattened due to the weather. The three sites were many miles apart, so data collection was very time consuming and had to be completed partially during Ramadan.
We would like to sincerely thank our colleagues in Pakistan, including scientific staff from the University of Agriculture Faisalabad (UAF), the National Agriculture Research Centre (NARC) and the Cereal Crops Research Institute (CCRI) for their hard work to complete the field experiments, co-ordinated by Dr Munir Zia from Fauji Fertilizer Company.
The wheat crop was harvested at all three sites in May 2018. The next steps are: manual separation of the wheat grain from the wheat spikes; threshing the wheat grain to separate the edible part from the husk; cleaning and weighing the wheat grain. A sample of the harvested grain from each treatment plot will be sent to the School of Biological Sciences, University of Nottingham for elemental analysis. This will show the effects of various treatments, either applied alone or in combination, on the zinc concentration of the grain.
The health and economic impact of genetic and agronomic biofortification will be calculated in terms of Disability Adjusted Life Years (DALYs), which is a measure of overall disease burden, expressed as the number of years lost due to ill-health, disability or early death.
Previously, we have explored the potential value of fertilizers in improving public health in Pakistan. This current study is the first – to the best of our knowledge – that will combine an assessment of both genetic and agronomic biofortification to explore the complementarity of these approaches.
We look forward to sharing the results in due course.