水分和腐植酸对燕麦果聚糖代谢的影响

探讨水分和腐植酸(HA)对燕麦不同器官非结构性碳水化合物(NSC)积累与分配的影响,进一步明确水分和HA对燕麦糖代谢和粒重形成的作用机制,可为旱作地区燕麦的推广种植提供理论指导和技术支撑。试验以‘蒙农大燕1号'和‘内燕5号'两个燕麦品种为材料,分别在旱作(无灌溉)和有限灌溉(拔节期和抽穗期每次灌水60 mm)两个水分条件下喷施HA与清水(CK),研究燕麦开花后不同时期NSC组分在茎、叶、穗中的动态变化以及叶片中碳代谢相关酶活性的变化。结果表明: 两个燕麦品种茎、叶、穗中的NSC组分含量均随开花后时间的延长先升高后降低,且两品种各器官中的NSC组分含量大致相同;与CK相比,在灌水条件下喷施HA后蒙农大燕1号穗部的果聚糖含量提升幅度明显大于旱作条件;喷施HA后蒙农大燕1号叶片中果聚糖外水解酶和转化酶活性分别显著提高了27.1%和30.6%,单穗粒重显著提高了55.9%,且与旱作条件下相比提高幅度更大;蒙农大燕1号籽粒千粒重和单穗粒重与叶片果聚糖含量呈显著正相关关系。综上,水分和腐植酸协同作用可以有效调节燕麦果聚糖的积累及主要代谢酶活性,从而提高千粒重和单穗粒重,促进产量形成。

Effects of moisture and humic acid on the metabolism of oat fructans

To provide theoretical guidance and technical support for oat production in dry farming area, we exa-mined the effects of moisture and humic acid (HA) on the accumulation and distribution of non-structural carbohydrates (NSC) in different organs of oat, as well as the mechanism of sugar metabolism and grain weight formation of oat. Two oat cultivars, ‘Mengnong Dayan 1' and ‘Neiyan 5', were used as experimental material. HA and clean water (CK) were foliar sprayed under dry framing (without irrigation) and limited irrigation (irrigated twice at jointing and heading stage). The dynamics of NSC components in stems, leaves and panicles, as well as the changes of carbon metabolism-related enzyme activities at different growth stages of oats after flowering were measured. Results showed that the trend of the contents of NSC in stems, leaves and panicles, in both two oat cultivars increased firstly and then decreased with the prolong of post-anthesis time. The contents of NSC in different organs were similar between two oat cultivars. Under irrigation treatment, the fructan content in panicle for Mengnong Dayan 1 of HA was higher than that of CK, with magnitude of enhancement being significantly greater than that corresponding treatment under dry farming. Under irrigation condition, the fructan, invertase activities in leaves and grain weight per panicle for Mengnong Dayan 1 of HA were increased by 27.1%, 30.6% and 55.9% compared with CK, respectively. Further, the increase trend under irrigation was stronger than that under dry farming condition. For Mengnong Dayan 1, the 1000-grain weight and grain weight per panicle were positively correlated with the content of fructan in leaves. In conclusion, the synergistic effect of moisture and humic acid could effectively regulate the accumulation of oat fructans and the activities of carbon metabolic enzymes, consequently promoting the formation of yield.