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1.
The International Maize and Wheat Improvement Center (CIMMYT) acts as a catalyst and leader in a global maize and wheat innovation network that serves the poor in the developing world. Drawing on strong science and effective partnerships, CIMMYT researchers create, share, and use knowledge and technology to increase food security, improve the productivity and profitability of farming systems and sustain natural resources. This people-centered mission does not ignore the fact that CIMMYT’s unique niche is as a genetic resources enhancement center for the developing world, as shown by this review article focusing on wheat. CIMMYT’s value proposition resides therefore in its use of crop genetic diversity: conserving it, studying it, adding value to it, and sharing it in enhanced form with clients worldwide. The main undertakings include: long-term safe conservation of world heritage of both crop resources for future generations, in line with formal agreements under the 2004 International Treaty on Plant Genetic Resources for Food and Agriculture, understanding the rich genetic diversity of two of the most important staples worldwide, exploiting the untapped value of crop genetic resources through discovery of specific, strategically-important traits required for current and future generations of target beneficiaries, and development of strategic germplasm through innovative genetic enhancement. Finally, the Center needs to ensure that its main products reach end-users and improve their livelihoods. In this regard, CIMMYT is the main international, public source of wheat seed-embedded technology to reduce vulnerability and alleviate poverty, helping farmers move from subsistence to income-generating production systems. Beyond a focus on higher grain yields and value-added germplasm, CIMMYT plays an “integrative” role in crop and natural resource management research, promoting the efficient use of water and other inputs, lower production costs, better management of biotic stresses, and enhanced system diversity and resilience.  相似文献
2.
Grains of 80 accessions of nine species of wild Triticum and Aegilops along with 15 semi-dwarf cultivars of bread and durum wheat grown over 2 years at Indian Institute of Technology, Roorkee, were analyzed for grain iron and zinc content. The bread and durum cultivars had very low content and little variability for both of these micronutrients. The related non-progenitor wild species with S, U and M genomes showed up to 3–4 folds higher iron and zinc content in their grains as compared to bread and durum wheat. For confirmation, two Ae. kotschyi Boiss. accessions were analyzed after ashing and were found to have more than 30% higher grain ash content than the wheat cultivars containing more than 75% higher iron and 60% higher zinc than that of wheat. There were highly significant differences for iron and zinc contents among various cultivars and wild relatives over both the years with very high broad sense heritability. There was a significantly high positive correlation between flag leaf iron and grain iron (r = 0.82) and flag leaf zinc and grain zinc (r = 0.92) content of the selected donors suggesting that the leaf analysis could be used for early selection for high iron and zinc content. ‘Chinese Spring’ (Ph I ) was used for inducing homoeologous chromosome pairing between Aegilops and wheat genomes and transferring these useful traits from the wild species to the elite wheat cultivars. A majority of the interspecific hybrids had higher leaf iron and zinc content than their wheat parents and equivalent or higher content than their Aegilops parents suggesting that the parental Aegilops donors possess a more efficient system for uptake and translocation of the micronutrients which could ultimately be utilized for wheat grain biofortification. Partially fertile to sterile BC1 derivatives with variable chromosomes of Aegilops species had also higher leaf iron and zinc content confirming the possibility of transfer of required variability. Some of the fertile BC1F3 and BC2F2 derivatives had as high grain ash and grain ash iron and zinc content as that of the donor Aegilops parent. Further work on backcrossing, selfing, selection of fertile derivatives, leaf and grain analyses for iron and zinc for developing biofortified bread and durum wheat cultivars is in progress. Nidhi Rawat, Vijay K. Tiwari, and Neelam Singh have contributed equally to the work.  相似文献
3.
In this research experiment, two commercial onion cultivars (Allium cepa L., cvs. Dorrcheh and Cebolla Valenciana) were grown in sand culture and exposed to two levels of selenium (Se) (0 and 25 µM) and two levels of sulfate (1 and 3 mM). According to the results obtained, addition of 25 µM Se in combination with 3 mM sulfate was not only effective in significant increase of onion bulb yield, but it significantly increased Se concentration of bulb. By considering the average consumption of onion in central Iran, the daily intake of Se via consumption of Se-biofortified onion is estimated to be 68.4–77.2 µg in spring and summer and 72.6–117.1 µg in fall and winter. These amounts of daily intakes of Se is higher than the sufficient levels of Se recommended by world health organization (WHO) but less than the maximum tolerable level of Se (400 µg Se per day) for human.  相似文献
4.
Poor zinc (Zn) nutrition of wheat is one of the main causes of poor human health in developing countries. A field experiment with no zinc and foliar zinc application (0.5% ZnSO4.7H2O) on bread wheat (8), durum wheat (3), and triticale (4) cultivars was conducted in a randomized block design with three replications in 2 years. The experimental soil texture was loamy sand with slightly alkalinity. The grain yields of bread wheat, triticale, and durum wheat cultivars increased from 43.6 to 56.4, 46.5 to 51.6, and 49.4 to 53.5 t ha−1, respectively, with foliar application of 0.5% ZnSO4.7H2O. The highest grain yield was recorded by PBW 550 (wheat), TL 2942 (triticale), and PDW 291 (durum), which was 5.22, 4.24, and 4.56% and significantly higher over no zinc. Foliar zinc application increased zinc in bread wheat, triticale, and durum wheat cultivars grains varying from 31.0 to 63.0, 29.3 to 61.8, and 30.2 to 62.4 mg kg−1, respectively. So, agronomic biofortification is the best way which enriching the wheat grains with zinc for human consumption.  相似文献
5.
Multiple element analyses were carried out to investigate variation in element concentrations in barley grains of 336 genotypes. Of 13 elements analyzed, Ba ranged from 0.2 to 8.9 mg kg−1, Ca from 186.4 to 977.5 mg kg−1, Cu from 1.5 to 9.8 mg kg−1, K from 353.2 to 7721.5 mg kg−1, Mg from 1049.8 to 2024.2 mg kg−1, Mn from 8.1 to 22.9 mg kg−1, Na from 55.9 to 627.9 mg kg−1, P from 2272.9 to 5428.8 mg kg−1, S from 880.7 to 1898.0 mg kg−1, Si from 19.1 to 663.2 mg kg−1, and Sr from 0.35 to 2.62 mg kg−1 in the barley grain. The least square means showed high Zn, Fe, Mg, P, and S concentration in AM-64 and AM-228 genotypes. The principal component analysis of element concentration showed four PCs explained 64.3% total variance. Strong positive correlations (p < 0.001) of Fe-Mn, Fe-S, S-Mn, Zn-P, Zn-Mg, Mg-P, Mg-Mn, and Ca-Sr were found. The identification barley genotypes that showed high elements concentration furnish valuable genetic resources for biofortification in future.  相似文献
6.
张城铭  周鑫斌 《土壤学报》2019,56(1):186-194
采用盆栽试验方法,研究土壤施硒和叶面喷硒两种施硒方式(均为硒酸钠形态)对水稻籽粒硒生物强化以及营养品质的影响机制。结果表明:等量施硒条件下,土壤施硒和叶面施硒两种方式均能显著提高水稻地上部和籽粒硒含量,土壤施硒水稻地上部和籽粒硒含量分别为叶面喷硒处理的8.9倍和5.3倍,说明在等量施硒条件下土壤施硒较叶面施硒更能有效提高籽粒硒含量。叶面喷硒处理的籽粒硒分配系数为土壤施硒的2倍,说明硒通过叶片向籽粒转运速率较通过根系到籽粒的转运速率更快。土壤施硒能够显著提高籽粒中镁、硫、铁、锰和锌等矿质营养元素含量。相比对照组,土壤施硒和叶面喷硒的水稻籽粒粗蛋白分别提高8%和4.5%,丝氨酸和酪氨酸含量说明施硒能够提高水稻营养品质,以土壤施硒效果更佳。  相似文献
7.
农业绿色发展是农业现代化的必由之路,土壤健康是农业绿色发展的基石。本文系统总结了国内外有关土壤健康的内涵、研究进展和发展趋势,探讨了提升土壤健康的途径和对策,并对我国未来健康土壤培育工程提出了建议和展望。健康土壤培育的核心是消除土壤障碍因子,深入挖掘土壤生物学潜力,增碳提高资源效率,强化生物学过程,协同地上和地下生物互作。通过优化土壤内部调节过程,最小化外部的投入,以实现土壤生产功能和其他生态服务的同步提升。健康土壤的培育是一个系统工程,需要对投入品-生产过程-产品品质-产品加工-废弃物循环等全产业链进行系统综合考虑,多学科交叉创新,政产学研用一体化联合攻关,同时还需要政策保障和激励措施,需要全社会行动起来。  相似文献
8.
Brassica vegetables are important source of dietary mineral elements. However, information on the genetic variability of mineral elements and its transmissibility is scanty but essential if the nutritional quality of cabbage is to be improved through breeding. Highly significant differences among cultivars and germplasms indicate the existence of adequate amount of variability. Mineral concentrations differed 6 fold for iron, 2.4 fold for zinc, 2.1 fold for copper, 2.3 fold for manganese, 1.7 fold for potassium, and 4 fold for calcium content. The higher magnitude of genotypic to phenotypic variance ratio for iron, zinc, manganese, potassium, and calcium indicates high transmissibility of minerals into next generation, while the meager differences between phenotypic and genotypic coefficient of variation indicate lesser influence of the environment on elemental accumulation.  相似文献
9.
It is still unclear if different sources of nitrogen (N) can variably influence grain accumulation of zinc (Zn), N, and phytate. We tested foliar treatments of 0 or 0.25% Zn as zinc sulfate in combination with 0 or 1% N as ammonium chloride, ammonium sulfate or urea sprayed on field-grown-wheat (Triticum aestivum L.) foliage at anthesis and 10 days later. Leaf burning caused by ammonium chloride significantly decreased grain yield. Grain N concentration was the highest in the urea +0.25% Zn treatment. Foliar N application influenced grain Zn concentration only if Zn was included in the spray. Grain phytate concentration was significantly decreased by both N and Zn sprays. Estimated Zn bioavailability in grains was the highest at 0.25% Zn and was not influenced by the N sources. Based on grain yield, grain N concentration, and Zn bioavailability in grains, foliar application of Zn + urea is an optimal strategy.  相似文献
10.
One sixth of the world’s population is suffering from hidden hunger that indicates a gross malnutrition particularly among children and women of third world countries. The deficiency of micro nutrients, especially iron (Fe) causes a number of ailments such as megaloblastic anemia and neural tube defects in poor population. There is a dire need to supplement iron in the diet. Current efforts implicate fortification of wheat flour and other grains with different iron formulations such as ethylenediaminetetraacetic acid (EDTA), FeSO4 and elemental iron. However, all such interventions are not sustainable due to logistic and quality assurance problems in resource-limited settings. For a long term solution, development of crop plants with increased micronutrients and iron bioavailability is essential. Therefore, biofortification of cereal grains using translational genomics approaches for enhancement of folate through genome editing in cereals is inevitable to mitigate the folate deficiency in poor remote population in a cost effective manner.  相似文献
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