小麦新品种济麦262抗旱性研究

Study on Drought Tolerance of New Wheat Variety Jimai 262

济麦262是新近育成的旱地小麦新品种,目前正在山东省大面积推广应用。本研究旨在明确其拔节期根系和地上部物质积累特性,揭示抗旱节水机理,为培育抗旱节水新品种提供理论指导和评价指标。于2017—2018年,在山东省农业科学院作物研究所济南试验基地,以济麦262及其亲本烟农19和临麦2号为试验材料,于管栽条件下进行雨养和充分浇水两个处理,比较3个品种拔节期根系特性、地上部生物量积累及其对供水的响应特征。结果表明,两种水分条件下3个品种拔节期根系总长度、总表面积和根尖总数在0～30、30～60、>90、60～90 cm土层范围内呈降低趋势;干旱胁迫降低了3个品种多数土层根系量及总根系量。充分浇水条件下,临麦2号和济麦262拔节期根系总长度、总表面积和根尖总数显著大于烟农19;而雨养条件下,济麦262则高于两个亲本,且深层(>90 cm)根系量也更大。此外,与两个亲本相比,济麦262拔节期地上部生物量对水分敏感性低,抗旱系数较高。雨养条件下拔节期根系总表面积与抗旱系数相关性较高,可作为评价品种抗旱性强弱的重要指标。

Jimai 262 is a new variety with drought tolerance and water saving property, which has been largely grown in Shandong Province. The purpose of this study was to make clear the characteristics of biomass accumulation in root and aboveground at jointing stage, reveal the drought resistant and water-saving mechanisms,and provide theoretical guidance and evaluation indexes for breeding new varieties with drought resistance. The experiment was conducted in 2017-2018 cropping season, and three varieties Jimai 262 and its parents Yannong 19 and Linmai 2 were used as materials and grown in barrels in the Jinan Base of Crop Institute, Shandong Academy of Agricultural Sciences. Two irrigation levels including rain-fed condition (no irrigation in the whole growing period, W0) and adequate watering condition (about 80% of soil water content, CK) were designed, and the phenotypic traits such as root characteristics and aboveground biomass at jointing stage were analyzed as well as the responses of the three varieties to irrigation level. The results showed that the total root length (TRL), total root surface area (TRSA) and total root tips (TRT) of the three varieties decreased at jointing stage in the soil layer of 0~30, 30~60,>90 and 60~90 cm under the two treatments. Drought stress decreased the amount of root in most soil layers and the total amount of root. Under the CK treatment, the TRL, TRSA and TRT of Linmai 2 and Jimai 262 were significantly higher than those of Yannong 19. Under the W0 treatment, Jimai 262 showed higher TRL, TRSA and TRT compared to its parents, especially the amount of root in deeper soil layer (>90 cm). Compared with the two parental varieties, Jimai 262 showed lower water sensitivity in the aboveground biomass at jointing stage, so it had higher drought tolerant coefficient (DTC). The TRSA at jointing stage was highly correlated with DTC under rainfed condition, which could be used for evaluating drought tolerance of wheat varieties.