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Foliar ZnSO4 application has been shown to be effective for increasing Zn concentration in wheat (Triticum aestivum L.) grain but is time and energy consuming. For promoting adoption of this practice by growers, a field experiment was conducted in two seasons to evaluate the effects of foliar Zn combined with six commonly used pesticides (three insecticides and three fungicides) applied at flowering or milk stage on Zn concentration and bioavailability in wheat grain and its milling fractions. Grains were fractionated into flour and bran for analysis of Zn, phytic acid (PA), and other nutrients (protein, P, K, Fe, and Mn). The results showed that foliar application of Zn together with various pesticides, irrespective of pesticide type, was as effective as foliar Zn application alone in improving Zn concentrations in whole grain and in its milling fractions. Combined foliar application of Zn with pesticides did not increase PA concentration but significantly increased the estimated Zn bioavailability in flour by 79.2%, in bran by 95.4%, and in grain by 94.5%. Zinc foliar application (with or without pesticides) at milk stage resulted in a higher Zn concentration and bioavailability in whole grain than Zn applied at flowering stage. There were no adverse effects of combined foliar application of Zn and pesticides on grain yield and other nutrients. Therefore, foliar Zn application can be safely applied with commonly used fungicides or insecticides (particularly at milk stage) to enrich Zn of the whole grain and particularly the flour and represents a useful practice for overcoming human Zn deficiency. [ABSTRACT FROM AUTHOR]

Low Zn content in wheat (Triticum aestivum L.), often associated with soil Zn deficiency, contributes to insufficient dietary intake of Zn and to widespread human Zn deficiency. Foliar Zn application has been shown to increase grain Zn concentration and bioavailability but is time and energy consuming in practice. A 2-yr split-plot field experiment was conducted to investigate how foliar N and P application at the early grain-filling stage affects nutritional qualities of whole grain and flour of winter wheat (cultivar Xiaoyan 22), whether these nutrients are applied alone, as is common in practice, or are combined with Zn applications (Zn+N, Zn+P and Zn+N+P). The results showed foliar N or P applied alone had little effect on Zn concentration and bioavailability. Foliar Zn+N generally resulted in higher Zn concentration and bioavailability in whole grain and grain fractions than did foliar Zn alone, while both foliar applications containing P resulted in lower Zn concentration and bioavailability than foliar Zn alone. Foliar Zn-containing fertilizers increased total Zn concentration in flour (averaged by 60.0% during 2012-2013 and 81.0% during 2013-2014), mainly from soluble Zn increases, while the corresponding Zn increase in bran was mainly from insoluble Zn. Amino acid concentrations in flour tended to decrease with application of foliar Zn or P alone, but increased with foliar N. Overall, our findings demonstrate foliar Zn can be co-applied with macronutrients, especially N, to increase practicality for farmers and to improve grain and flour nutritional quality to benefit human health. [ABSTRACT FROM AUTHOR]

Revealing the response of cereal yield and water use efficiency (WUE) to water management practices is crucial for achieving high and stable grain yields in drylands. A 3-yr field study was conducted to develop a high-yield, water-saving cultivation strategy for winter wheat in the Loess Plateau of China. The study's treatments included (i) a control (CK), that is, no mulch or fertilizer, (ii) nitrogen and phosphorus fertilizers (NP), (iii) plastic film mulch plus fertilizers (NP+PF), (iv) straw mulch plus fertilizers (NP+S), and (v) plastic film combined with straw mulch plus fertilizers (NP+PF+S). The results indicated that, compared with CK, the NP treatment improved the grain yield (112%) and WUE (96%) of winter wheat but resulted in a 12% reduction in soil water storage after the jointing stage. With the NP+S treatment, there was no difference recorded in grain yield, yield components, or WUE of winter wheat (relative to the NP treatment). With the NP+PF treatment, there was a 53% increase in grain yield, a 46% increase in WUE, and a 21% increase in soil water storage after jointing compared to the NP treatment. The plastic film could also modify soil temperature, resulting in maximized soil water retention. Additionally, the NP+PF and NP+PF+S treatments resulted in similar results. Taking into account agricultural, environmental, and economic factors, in addition to optimal fertilization (NP), plastic film mulch is the recommended practice for maximum yield and water retention in tablelands, whereas plastic film combined with straw mulch is recommended in terraces. [ABSTRACT FROM AUTHOR]

Although foliar application of Zn is highly efficient in improving Zn concentration in wheat (Triticum aestivum L.) grain, it may be beneficial to better understand its effectiveness when combined with foliar applications of N or P. A 2-yr field experiment was conducted to evaluate the efficacy of concurrent ZnSO4, and commonly used N and P applications on grain Zn, and other nutritional quality indices in wheat. On average, grain Zn concentration increased by 84,83, and 55% following foliar application of Zn, Zn+N, and Zn+P, respectively. The Zn concentration following foliar application was much greater in the leaves than in the glume or stem. The reduction in the Zn content and the distribution of Zn in the grain and leaves was similar following foliar-applied Zn and foliar-applied Zn+P. This suggests that absorption of Zn in the vegetative tissues (e.g., leaf) was reduced with the addition of P in the foliar spray, but translocation of Zn from the leaf to grain was not inhibited by P. Foliar Zn+N application significantly increased grain protein, Fe, and Ca concentrations, and foliar Zn+P application significantly increased Fe and Ca concentrations. Foliar application of Zn, Zn+N, and Zn+P significantly decreased grain phytic acid (PA)/Zn, PA/Fe, and PA/ Ca molar ratios. The results of this study suggest that the inclusion of Zn in commonly used foliar applications of N or P may be effective for increasing grain Zn concentration in wheat. [ABSTRACT FROM AUTHOR]

Water status and N fertility are the critical factors in micronutrient accumulation in grain of wheat (Triticum aestivum L.). This field experiment was conducted to examine whether the changes in N fertility and water management can influence micronutrient concentration and bioavailability in wheat grown in soils with existing low micronutrient concentrations within drought-prone regions. The results indicate that fertilizer N (120 or 240 kg N ha-1) application significantly improved grain Zn, Fe, Cu, and protein concentration with a mean increase of 24.7, 39.2, 18.6, 23.9% in 2009/2010 and 8.9, 21.1, 10.5, 29.6% in 2010/2011, respectively, when compared with the unfertilized treatment. However, grain Mn concentration in both cropping seasons were significantly decreased (on average by 8.4%) by N fertilization. Compared to the no irrigation treatment (NI), the water-saving treatment (RF) significantly increased grain Zn by an average of 13.2%, grain Fe by 22.2%, grain Mn by 4.4%, and grain protein by 8.3%. Grain phytic acid (PA) concentration and PA/micronutrient ratios were on average 28.0 and 32.2% lower in the N fertilized treatment than in the unfertilized treatment. Decreasing the N application rate from 240 to 120 kg N ha-1 did not affect much of the grain nutritional quality, with the exception of a significant decrease in grain Zn concentration, and a significant increase in grain PA concentrations and the PA/Zn molar ratio. These data demonstrate the importance of monitoring grain Zn concentrations, and perhaps the inclusion of supplemental Zn when adopting alternative N fertilizer management regimes in northern China. [ABSTRACT FROM AUTHOR]