土壤紧实度变化对小麦籽粒产量和品质的影响

以济南17(强筋品种)、烟农15(中筋品种)、鲁麦22(弱筋品种)为供试品种，设置人为碾压和不碾压2种处理，研究了土壤紧实度(以土壤容重表示)变化对不同类型小麦品种的籽粒产量和加工品质的影响。结果表明，随着土壤紧实度提高，3个品种的分蘖成穗率均显著降低，从而导致单位面积穗数和籽粒产量降低。3个品种相比较分蘖成穗率低的鲁麦22籽粒产量降幅最大。相关品质指标测定结果显示，提高土壤紧实度，对3个品种的蛋白质含量、湿面筋含量、沉淀值和吸水率均无显著影响，但济南17的面筋指数明显降低，面团断裂时间和面团稳定时间显著缩短，单位重量面粉烘焙所得的面包体积变小，而烟农15和鲁麦22受影响较小。其原因可能与土壤紧实度提高条件下济南17籽粒中谷蛋白／醇溶蛋白比例和谷蛋白大聚体含量降低有关。将济南17面团流变学特性年际间变化幅度与紧实度变化的处理效应相比较发现，土壤紧实度是影响强筋小麦品种品质性状稳定性的重要因素之一。

Effects of soil compaction on grain yield and quality of wheat

Three cultivars differing in gluten strength (Jinan 17,strong;Yannong 15,middle;Lumai 22,weak) were grown in two environment (soil compacted artificially and the control) to investigate the effects of soil compaction on the grain yield and processing quality.The experimental results indicated that fertile tiller percentage of all cultivars decreased significantly with soil compaction leading to remarkable decline in spike number and grain yield per unit area.Among three cultivars,the grain yield of Lumai 22 was reduced most severely owing to its lowest fertile tiller percentage.As grain and flour quality were concerned,It was shown that there was no significant change due to soil compaction in the protein content,wet gluten content,sedimentation value and water absorption percentage.However,striking decline in gluten index,shorten dough stability time and the time of dough to break down as well as reduced loaf volume of Jinan 17 were observed in response to soil compaction,which may result from reduced glutenin:gliadin ratio and the content of macro-polymer of glutenin.When the comparison was made between the fluctuation from year to year and the difference among trentments of Jinan 17 in dough rheological properties,it was found that soil compaction was one of the most important factors affecting quality consistence of cultivars with strong gluten.