碳氮供给对小麦离体穗培养粒重、微量元素及蛋白质含量的影响

Effect of Carbon and Nitrogen Concentration in Culture Solution on Weight,Micronutrient and Protein Content of Wheat Grain by Detached Spike Culture

为了解碳氮供给与小麦粒重、Fe、Zn、Mn、Cu等微量元素以及蛋白质含量的关系,在离体穗培养条件下研究了灌浆初期和灌浆中期不同浓度C(蔗糖)、N(硝酸铵)供给对小麦粒重、微量元素(Fe、Zn、Mn、Cu)和蛋白质含量的影响。结果表明,随着培养基糖浓度的增大,粒重和Fe、Mn含量都表现为先升高后降低的趋势,在4%糖浓度时,均达到最高值;籽粒Zn、Cu和蛋白质含量表现为随糖浓度增大而持续降低。随着培养基N浓度的增加,粒重和Fe、Zn、Mn、Cu含量多表现为先升高后降低的趋势,且多在N浓度为0.07%时达到最高值,尤以灌浆中期开始的培养表现明显;籽粒蛋白质含量表现为随N浓度增大而持续增加。由此可见,外源C、N供给对粒重、微量元素和蛋白质含量有明显的调控效应。一定的糖供给可同时提高粒重和Fe、Mn含量,一定的N供给可同时提高粒重及微量元素和蛋白质含量。

Wheat is a major staple food crop in many parts of the world in terms of cultivated area and food source, contributing 28% of the world edible dry matter and up to 60% of the daily calorie intake in several developing countries. Therefore, the composition and nutritional quality of the wheat grain has a significant impact on human health and well-being, especially in developing countries. During the twentieth century, plant breeding and improved crop management techniques successfully increased grain yield of wheat, but the micronutrient and protein concentration were not improved simultaneously. Carbon and nitrogen supply can impact grain weight and protein concentration, however, their regulatory effects on micronutrient has not been reported. In this paper, the effect of carbon and nitrogen supply on grain weight, grain micronutrient and protein concentration were studied under the detached spike culture 7 days and 16 days after anthesis. The results showed that the grain weight and Fe and Mn concentration were increased with the increase of sucrose content in culture solution, and decreased in high sucrose treatment（6%）, while grain Zn, Cu and protein content decreased continuously . Grain weight and grain Fe, Mn, Zn, Cu concentration increased with the increase of nitrogen content in culture solution, and decreased in high ni- trogen treatment（1.05%）, while grain protein content improved continuously. It can be seen that external carbon or nitrogen supply had an important regulating role for grain weight, grain micronutrient and protein content. In some extent, raising sucrose supply can increase grain weight and grain Fe, Mn content simultaneously, and raising nitrogen supply can increase grain weight and grain Fe, Zn, Mn, Cu and protein content simultaneously.