以河套灌区小麦主栽品种永良4号为研究对象,选择20个农户地块定位观测,探讨不同土层土壤盐分含量对小麦产量及其构成因素的影响,研究小麦在该地区的耐盐性及其生态适宜区。结果表明,以小麦苗期0~10cm土壤饱和浸提液电导率(ECe)作为根层盐分指标来评判小麦的耐盐性最具代表性,该土层对应的小麦耐盐指数为10.465;土壤盐分与小麦各产量构成因素之间均呈显著负相关,尤其与公顷穗数的相关性更强;根据小麦耐盐性分析,以小麦相对产量下降幅度≤10%、10%~25%、25%~50%和≥50%作为划分标准,将区域耕地划分为小麦生产最适宜区、适宜区、次适宜区和不适宜区,其对应的小麦苗期0~10cm土壤ECe分别为≤4.972、4.972~6.747、6.747~9.196和≥9.196dSm-1。
Using the major local wheat cultivar Yongliang 4, the effect of salinity in different soil layers on yield and its compo- nents of wheat was investigated in 20 farmers' fields in Hetao Irrigation District which was in Inner Mongolia, China. And salt tolerance of wheat and its ecological adaptable region were studied in this district. The results showed that ECe of 0 to 10 cm soil layer at wheat seedling stage was the most representative as the root-zone salinity index to analysis wheat salt tolerance, the salt tolerance index of wheat was 10.465 for this soil layer. There were significant negative correlations between soil salinity and wheat yield components, especially between soil salinity and spike number per hectare. According to the wheat salt tolerance, and the wheat relative yield reduction of 〈10%, 10-25%, 25-50%, and 〉50% as the division standard, we divided the farm land into the most suitable region, suitable region, sub-suitable region and unsuitable region, where the electrical conductivities of satura- tion extract of the 0-10 cm soil at wheat seedling stage were _〈4.972, 4.972-6.747, 6.747-9.196, and 〉9.196 dS m-1, respectively.