Farmers' and millers' experiences and attitudes towards the production and processing of zinc biofortified wheat in Pakistan: a mixed methods study.

Zinc biofortified wheat may be a sustainable strategy to increase zinc intake in areas where fortification and dietary diversification are not feasible or are limited by household purchasing power. This convergent mixed methods study aimed to explore the farmers' and millers' experiences and attitudes towards the production and processing of zinc biofortified wheat in Pakistan. A telephone survey was conducted with farmers (n = 418) who were provided with Zincol-2016 biofortified wheat seed for the 2019-2020 growing season, as part of a wheat grain micronutrient mapping study across Punjab Province. The survey explored the farmers' experiences of growing Zincol-2016 and whether they opted to grow it again in the subsequent season. Semi-structured focus group discussions were undertaken in a separate group of farmers in Khyber Pakhtunkhwa (KP) province (n = 12) who grew Zincol-2016 for the BiZiFED2 RCT. Millers were also interviewed in KP, both those who had processed Zincol-2016 for the trial (n = 12) and those who had no experience of processing biofortified wheat (n = 12). Survey data were analyzed using descriptive statistics and transcripts of focus groups were analyzed using thematic analysis. Nearly half of farmers who responded to the survey (47%) re-cultivated Zincol-2016 in the following season. The drivers for Zincol-2016 re-cultivation were seed availability (100%), grain yield and growth resistance (98%), quality of the flour from the previous harvest (97%) and nutritional benefit (94.5%). Discussions with farmers suggested that the main motivators for potential scale-up of biofortified wheat were the perceived quality of the grain, wheat, and flour. Millers saw it as an opportunity to expand their business. Farmers and millers valued the health benefits of the wheat. Challenges for scale-up include the need of additional support to produce it, unfamiliarity with the biofortification process, production costs, and external threats to the supply chain. Farmers and millers showed a strong implicit preference for Zincol-2016 over alternative varieties. Crop performance and product yield were the most cited motivators for growing Zincol-2016. Farmers and millers are willing to produce and process biofortified wheat if financial and educational support is provided.

Ceballos-Rasgado M ，Ajmal S ，Mahboob U ，Ander EL ，Zia M ，Moran VH ，Joy EJM ，Zaman M ，Ohly H ，Lowe NM ... -  《Frontiers in Nutrition》

Biofortified Wheat Increases Dietary Zinc Intake: A Randomised Controlled Efficacy Study of Zincol-2016 in Rural Pakistan.

A new variety of zinc biofortified wheat (Zincol-2016) was released in Pakistan in 2016. The primary aim of this study was to examine the effects of consuming Zincol-2016 wheat flour on biochemical and functional markers of zinc status in a population with widespread zinc deficiency. An individually-randomised, double-blind, placebo-controlled cross over design was used. Fifty households were recruited to participate in the study, with each household included at least one woman of reproductive age (16-49 years) who was neither pregnant nor breast feeding or currently taking nutritional supplements. All households were provided with control flour for an initial 2-week baseline period, followed by the intervention period where households were randomly allocated in a 1:1 ratio to receive biofortified flour (group A; n = 25) and control flour (group B; n = 25) for 8-weeks, then switched to the alternate flour for 8-weeks. The trial has been registered with the ISRCTN (https://www.isrctn.com), ID ISRCTN83678069. The primary outcome measure was plasma zinc concentration, and the secondary outcome measures were plasma selenium and copper concentrations, plasma copper:zinc ratio and fatty acid desaturase and elongase activity indices. Nutrient intake was assessed using 24-h dietary recall interviews. Mineral concentrations in plasma were measured using inductively coupled plasma mass spectrometry and free fatty acids and sphingolipids by mass spectrometry. Linear Mixed Model regression and General Linear Model with repeated measures were used to analyse the outcomes. Based on an average flour consumption of 224 g/day, Zincol-2016 flour provided an additional daily zinc intake of between 3.0 and 6.0 mg for white and whole grain flour, respectively. No serious adverse events were reported. This resulted in significant, increase in plasma zinc concentration after 4 weeks [mean difference 41.5 μg/L, 95% CI (6.9-76.1), p = 0.02]. This was not present after 8 weeks (p = 0.6). There were no consistent significant effects of the intervention on fatty acid desaturase and elongase activity indices. Regular consumption of Zincol-2016 flour increased the daily zinc intake of women of reproductive age by 30-60%, however this was not associated with a sustained improvement in indices of zinc status.

Lowe NM ，Zaman M ，Khan MJ ，Brazier AKM ，Shahzad B ，Ullah U ，Khobana G ，Ohly H ，Broadley MR ，Zia MH ，McArdle HJ ，Joy EJM ，Bailey EH ，Young SD ，Suh J ，King JC ，Sinclair J ，Tishkovskaya S ... -  《Frontiers in Nutrition》

Zinc-biofortified wheat accumulates more cadmium in grains than standard wheat when grown on cadmium-contaminated soil regardless of soil and foliar zinc application.

Zinc (Zn)-biofortified wheat may contribute to decreasing widespread human Zn deficiency. Such genotypes may also accumulate cadmium (Cd) in grains that would expect to be decreased by Zn application. However, the influence of soil and foliar Zn application on grain Cd accumulation in Zn-biofortified versus standard wheat is unknown. In our experiment, we grew standard (Faisalabad-2008) and Zn-biofortified (Zincol-2016) wheats in pots having uncontaminated (T0) or Cd-spiked (8 mg kg-1) soil. Plants in Cd-amended pots were treated with no Zn (T1), 8 mg Zn kg-1 to soil at sowing (T2), 0.5% w/v ZnSO4·7H2O to foliage at booting and heading (T3), or soil (as in T2) + foliar (as in T3) Zn application (T4). Only in the uncontaminated control, grain yield of Faisalabad-2008 was greater than Zincol-2016. Any Zn application to Zincol-2016 grown in Cd-spiked pots increased grain yield compared with the uncontaminated control. In both cultivars, grain Zn concentration was influenced more by foliar than soil Zn application. However, Zincol-2016 had 6 to 14 mg more Zn kg-1 in grains than Faisalabad-2008 in the comparable treatments. Cadmium exposure (T1 vs. T0) decreased grain yield of only Faisalabad-2008, and decreased grain Zn concentration only in Zincol-2016. Without any Zn application, grain Cd concentration in both cultivars exposed to Cd was above the permissible level (0.20 mg kg-1). Zinc application decreased grain Cd concentration, although it remained above the permissible level in both cultivars except in Faisalabad-2008 when treated with soil + foliar Zn. Foliar Zn application decreased grain Cd concentration more than soil Zn application, and more in Zincol-2016 than Faisalabad-2008. In the comparable Cd-spiked treatments, Zincol-2016 had 73 to 134% higher grain Cd concentration than Faisalabad-2008. The Zn-biofortified genotypes accumulating toxic metals may pose serious health issues. Therefore, future breeding for biofortification should focus on the selective accumulation of Zn.

Hussain S ，Khan AM ，Rengel Z 《-》

Zinc fertilisation increases grain zinc and reduces grain lead and cadmium concentrations more in zinc-biofortified than standard wheat cultivar.

Given that plant uptake and transport systems for metals have some similarities, zinc (Zn)-biofortified cultivars may concurrently accumulate non-essential toxic heavy metals in grains. However, Zn-biofortified cultivars have never been tested for heavy metal accumulation in grains. In a pot experiment, we compared Zn-biofortified wheat (Zincol-2016) with a standard wheat (Faisalabad-2008) cultivar on heavy-metal-contaminated soils for yield response and grain accumulation of Zn, lead (Pb) and cadmium (Cd), without or with Zn fertilisation (8mgZnkg-1). The soils, collected from agricultural fields in (i) industrial zone and (ii) peri-urban area, had been receiving industrial and city effluents for >20years. In the two soils, Zn fertilisation significantly (P≤0.05) increased grain yield of both cultivars. Zinc fertilisation increased grain Zn concentration of Zincol-2016 and Faisalabad-2008 by respectively 32 and 18% in industrial-zone soil, and by 15 and 2% in peri-urban soil. Averaged across Zn rates, Zincol-2016 accumulated in grains more than double the Zn amount than Faisalabad-2008 in industrial-zone soil. At 0mgZnkg-1, grain Pb and Cd concentrations were respectively 26 and 33% greater in Zincol-2016 than Faisalabad-2008 in industrial-zone soil, and 86 and 50% greater in Zincol-2016 than Faisalabad-2008 in peri-urban soil. Zinc fertilisation significantly (P≤0.05) decreased concentration of Pb and Cd in grains of both cultivars. In industrial-zone soil, a toxic level of Pb in grains (0.24mgkg-1) was attained at control rate of Zn by Zincol-2016, and was decreased to a safe level (0.07mgkg-1) by application of 8mgZnkg-1. Therefore, biofortified cultivars should not be grown in contaminated soils, and/or sufficient Zn must be applied, to decrease accumulation of non-essential toxic heavy metals in grains. Moreover, future breeding efforts should be directed toward selection of biofortified cultivars that would selectively accumulate Zn in grains, but not the contaminants.

Qaswar M ，Hussain S ，Rengel Z 《-》

Community Perceptions of Zinc Biofortified Flour during an Intervention Study in Pakistan.

Mahboob U ，Ceballos-Rasgado M ，Moran VH ，Joy EJM ，Ohly H ，Zaman M ，Lowe NM ... -  《Nutrients》