Responses of Purple Rice Genotypes to Nitrogen and Zinc Fertilizer Application on Grain Yield, Nitrogen, Zinc, and Anthocyanin Concentration

Purple rice is recognized as a staple food for humans and as a source of anthocyanins and micronutrients such as zinc (Zn). This study examined how nitrogen (N) and Zn fertilizers affected grain yield and grain N, Zn, and anthocyanin concentration among purple rice genotypes. Six purple rice genotypes (PIZ, KAK, KS, KH-CMU, KDK, and HN) were grown under two levels of N, the optimum N60 (60 kg/ha) and high N180 (180 kg/ha) rates, along with three Zn application methods (no Zn application (Zn0), soil Zn application (ZnS; 50 kg ZnSO4/ha), and foliar Zn spray (ZnF; 0.5% ZnSO4 at the rate of 900 L/ha three times at heading, flowering, and early milk stages). Grain yield of the five purple rice landraces increased by 21–40% when increasing N from N60 to N180, although no response was found with HN. The higher N rate increased grain N concentration by 10–50% among the genotypes, while anthocyanin concentration increased by 100–110% in KAK and KS, and grain Zn was increased in KS. Applying ZnS increased grain yield by 16–94% but decreased anthocyanin and N concentrations compared to the control Zn0. Applying ZnF effectively increased grain Zn concentration by 40–140% in the genotypes without adversely impacting grain anthocyanin or N concentration. This study demonstrated that the appropriate management of N and Zn fertilizers for specific purple rice genotypes would be one way to increase productivity and grain N, Zn, and anthocyanin concentration.

EFFECTS OF NITROGEN AND ZINC TREATMENTS AT DIFFERENT DOSES ON MAIZE YIELD AND YIELD COMPONENTS UNDER KAHRAMANMARAŞ CONDITIONS

This study was carried out in 2019 in Kahramanmaraş University Field Crops Department to determine nitrogen and zinc fertilizer needs of maize plants in Kahramanmaraş Region. Experiments were conducted in split-plots design with 3 replications. Soil nitrogenous fertilizer (Urea) treatments were arranged as: 0 kg/da (N0), 15 kg/da (N15), 30 kg/da (N30). Foliar zinc treatments were arranged as 0 ppm (Zn0), 2500 ppm (Zn5), 5000 ppm (Zn10). Dekalp DKC6890 hybrid maize variety was used as the plant material of the experiments. Present findings revealed that nitrogen and zinc treatments had significant effects on the first cob height, cob length, cob thickness, number of rows per cob, number of kernels per cob and kernel yield of maize plants, but the effects of nitrogen and zinc treatments on plant height and thousand kernel weight were not found to be significant.

Improving Grain Zinc Concentration in Wetland and Upland Rice Varieties Grown under Waterlogged and Well-Drained Soils by Applying Zinc Fertilizer

The objective of this study was to evaluate the responses in grain yield and zinc concentration of wetland and upland rice varieties to Zn fertilizer application and different growing conditions. The wetland (Chainat 1; CNT1) and upland (Kum Hom CMU; KH CMU) rice varieties were grown under waterlogged and well-drained soil conditions with or without Zn fertilizer application. Zinc fertilizer (ZnSO4) was applied at 0 and 60 kg ha−1 in three stages at tillering, booting, and flowering. In the wetland variety, CNT1, grain yield decreased by 18.0% in the well-drained soil compared to the waterlogged conditions, but there was an 8.9% decrease in grain yield in the waterlogged soil compared to the well-drained soil in the upland variety, KH CMU. Applying Zn fertilizer affected yields differently between the varieties, decreasing grain yield by 11.9% in CNT1 while having no effect in KH CMU. For grain Zn concentrations in brown rice, applying Zn fertilizer increased Zn concentration by 16.5–23.1% in CNT1 and KH CMU under both growing conditions. In the well-drained soil, applying Zn fertilizer increased straw Zn concentration by 51.6% in CNT1 and by 43.4% in KH CMU compared with the waterlogged conditions. These results indicated that the wetland and upland rice varieties responded differently to Zn fertilizer application when grown in different conditions. Applying Zn fertilizer in the appropriate rice variety and growing conditions would help farmers to improve both the desirable grain yield and Zn concentration in rice.

Varietal response of maize to nitrogen and zinc fertilizer in Minna Southern Guinea Savanna of Nigeria

A field experiment was conducted in 2018 and 2019 seasons at the Teaching and Research Farm of the Federal University of Technology, Minna to determine the varietal response of maize to nitrogen and zinc fertilizer in Minna. The treatments included four levels of N: 0, 30, 60 and 90 kg ha-1, three levels of Zn: 0, 2.5 and 5 kg ha-1 and two varieties of maize (Oba Super 2 and Suwan-1-SR). The experimental design was a 4×3×2 factorial design fitted in a randomized complete block design with three replications. The data collected were, plant height, number of leaves, cob weight, cob length, stover yield, grain yield and 1000 grain weight. All data collected were subjected to analysis of variance and the means were separated using Duncan Multiple Range Test. Highest plant height (43.69 and 44.37 cm) were obtained in 60 and 90 kg N ha-1 treatment application respectively in year 2018 at 3 Week After Sowing (WAS), these heights were significantly different from that of control (0 kg N ha-1). Zinc (Zn) fertilization has no significant effect on maize height at all growth stage of maize in year 2018. Application of Zn produced significantly taller plants than those without Zn application at 3 and 9 WAS in 2019. The treatment 60 kg N ha-1 had significantly higher yield (27873.7 kg ha-1) than others but similar to 90 kg N ha-1 (2512.4 kg ha-1). Application of 60 kg N ha-1 increased with 12 % than the 0 kg N ha-1 on maize yield in 2019. There was response to Zn fertilization on stover and grain yields. The interaction effects were significant on stover yield. The nitrogen rate of 60 kg N ha-1 and the zinc rate of 2.5 kg were optimum for maize grain yield in Minna, both Oba Super 2 and Suwan-1-SR performed better in the study.

Agronomic Biofortification of Zinc in Pakistan: Status, Benefits, and Constraints

Micronutrient malnutrition (e.g., zinc) is one of the major causes of human disease burden in the developing world. Zinc (Zn) deficiency is highly prevalent in the Pakistani population (22.1%), particularly in women and children (under 5 years) due to low dietary Zn intake. In Pakistan, wheat is the primary staple food and is poor in bioavailable Zn. However, the number of malnourished populations has decreased over the last decade due to multiplied public awareness, accelerated use of Zn fertilizers (particularly in wheat and rice), initiation of several national/international research initiatives focusing on Zn biofortification in staple crops and availability of supplements and Zn fortified meals merchandise, nonetheless a large number of people are facing Zn or other micronutrient deficiencies in the country. There are few reports highlighting the significant increase in daily dietary Zn uptake in population consuming biofortified wheat (Zincol-2016) flour; indicating the positive prospect of biofortification interventions up scaling in lowering the risk of dietary Zn deficiency in rural and marginalized communities. Zinc fertilizer strategy has not only helped in enhancing the grain Zn concentration, but it also helped in improving crop yield with high economic return. In addition, Zn biofortified seeds have exhibited strong inherent ability to withstand abiotic stresses and produce higher grain yield under diverse climatic conditions. However, there are many constraints (soil, environment, genetic diversity, antinutrients concentration, socioeconomic factors etc.) that hinder the success of biofortification interventions. This review highlights the status of Zn deficiency in Pakistan, the success of agronomic and genetic biofortification interventions. It also discusses the economics of agronomic biofortification and cost effectiveness of Zn fertilization in field conditions in Pakistan and the potential of Zn biofortified seeds against abiotic stresses. Furthermore, it also highlights the constraints which limit the sustainability of biofortification interventions.