苗期根系的氮素吸收与利用效率是决定植株生长发育及产量收益的关键因素，研究氮肥调控下小麦苗期根系生物量及其相关形态学的遗传调控对培育高产稳产小麦品种具有重要意义。本研究利用扬麦16/中麦895构建的DH群体，分别在硝酸钙浓度为0 mmol L⁻¹（空白对照）、0.05 mmol L⁻¹（低氮）、2.0 mmol L⁻¹（高氮）3个梯度下进行液体培养，对4个根系生物量相关性状和5个根系结构性状进行基因定位，及连锁标记遗传转化研究。结果表明，不同氮肥处理与基因型间存在显著差异，根系生物量相关性状与结构性状间呈显著正相关，范围在0.20-0.98。基于全基因组660K SNP高密度遗传图谱，共定位到51个调控根系性状QTL，主要分布在12个根系性状调控基因富集区。并发掘出12个受氮肥调控影响的根系性状新基因，包括1AL染色体上携带受0氮调控的1个基因、1DS携带受高氮调控2个、4BL携带受高氮和低氮调控5个、7DS和7DL分别携带受低氮调控的3个和1个基因。4DS染色体上与Rht-D1 基因临近区域携带有控制根系性状且遗传表现稳定的基因QRRS.caas-4DS，解释表型变异为13.1%。12个根系性状基因富集区包括28个QTL位点，其中6BL和7BL染色体上的两个富集区C10和C11较为重要，主要控制根系干重、根表面积和幼苗干重等性状，连锁标记AX-109558906-6B和AX-95025477-7B已转化成育种可用的KASP标记。本研究发掘的QTL位点、QTL富集区及开发的KASP标记将有助于小麦育种工作中的苗期根系性状遗传改良。

Dumpling is one of the most important traditional wheat products in China. Dumpling quality is determined by the characteristics of both flour and filling, thus improvement of flour quality plays an important role in improving dumpling quality. Thirty-nine Shandong winter wheat cultivars and advanced lines sown in Jinan, Shandong Province, China, in the 2008-2009 cropping season were used to determine genetic variation in Chinese raw dumpling quality and its relationship with flour characteristics. Large variations were observed for protein quality parameters in comparison with starch properties. Variation in color of the raw dumpling sheet was broader than that of sensory evaluation parameters of boiled dumpling among tested wheat cultivars, indicating the large influence of filling on dumpling color. Two cultivars, Jimai 20 and Zimai 12, were identified as possessing very good quality of raw dumpling, and 21 cultivars and advanced lines showed good quality. Protein and total starch content influenced the L* value of raw dumpling sheets. L* value at 0 and 2 h after sheeting were significantly influenced by protein content (r=-0.46 and -0.52, P<0.01) and total starch content (r=0.55 and 0.57, P<0.01), respectively. Flour yellow pigment was significantly corrected with a* (r=-0.67 and -0.62, P<0.01) and b* (r=0.87 and 0.84, P<0.01) value of raw dumpling sheets at 0 and 2 h after sheeting, respectively. Gluten strength parameters such as farinograph mixing tolerance index (MTI, r=-0.55, P<0.01) were positively associated with appearance. MTI and energy were also significantly and positively correlated with elasticity of raw dumpling, with r=-0.54 and 0.47 (P<0.01). The positive relationships between peak viscosity (r=0.51, P<0.01), breakdown (r=0.54, P<0.01), and smoothness of raw dumpling were also observed. Therefore, it is suggested that breeding programs should give more attention to gluten strength and starch pasting parameters for raw dumpling quality improvement.