铵硝配比对不同芝麻品种苗期生长及养分吸收的影响  

Effects of different nitrogen form and ratio on growth and nutrient uptake of different sesame cultivars

作　　者：徐子先[1] 秦璐[1] 李银水[1] 韩配配 廖祥生[1] 胡小加[1] 谢立华[1] 余常兵[1] 张秀荣[1] 廖星[1] 

机构地区：[1]中国农业科学院油料作物研究所/农业部油料作物生物学与遗传育种重点实验室,湖北武汉430062

出　　处：《中国油料作物学报》2017年第2期204-212,共9页Chinese Journal of Oil Crop Sciences

基　　金：中国农业科学院创新工程-油料所(CAAS-ASTIP-2013-OCRI);杰出青年英才计划项目(1610172015004)

摘　　要：为了解芝麻苗期生长对氮素形态和配比的要求,明确芝麻氮肥施用适宜的铵硝比,以长江流域主栽芝麻品种中芝13和黄淮流域主栽芝麻品种漯12为材料,采用室外营养液培养方式,根据铵态氮(NH_4^+-N)和硝态氮(NO_3^--N)摩尔浓度比例的不同设置7个处理(10∶0、9∶1、3∶1、1∶1、1∶3、1∶9、0∶10),定期测定和分析营养液p H值、植株生物量、根系形态参数、地上部和根部养分(N、P、K、Ca、Mg)浓度、游离NH_4^+-N和NO_3^--N浓度等。结果表明:高比例NH_4^+-N处理(10∶0、9∶1和3∶1)显著抑制了芝麻苗期生长,主要表现为植株矮小、叶片枯焦、根系粗短,甚至死亡,随着NH_4^+-N比例的增加,抑制程度越明显。两个芝麻品种对NH_4^+毒害的耐受能力不同,中芝13更耐受NH_4^+毒害。铵硝配比1∶9时,两个芝麻品种植株生物量达到最大值,根系最为发达,根际p H值维持在适宜的范围内;其中,中芝13整株干重、总根长和根系总表面积较完全NO_3^--N处理(0∶10)分别显著增加了47%、29%和15%,植株地上部和根系N、P、K浓度较完全NO_3^--N处理分别增加了5%、17%、9%和10%、32%、13%;铵硝配比1∶9对漯12的生物量及养分吸收利用与完全NO_3^--N处理相比没有显著差异。因此,适当加入铵态氮可以提高芝麻苗期生物量,促进根系的生长,铵硝比为1∶9较适合芝麻幼苗的生长及养分的吸收。在芝麻田间氮素施肥中,建议以NO_3^--N为主,同时根据芝麻品种特性及土壤供氮等条件合理配施NH_4^+-N。To explore the effects of nitrogen form and ratio （NH4^＋-N/NO3^--N ratio） on growth and nutrient uptake of sesame seedlings, 2 sesame cultivars Zhongzhi 13 and Luo 12 were employed in hydroponics with 7 NH4^＋-N/NO3^--N ratio treatments （10：0, 9：1, 3：1, 1：1, 1：3, 1：9, 0：10. pH values of nutrient solution and plant phenotype were regularly measured. Plant biomass, root morphological parameters, and N, P, K, Ca, Mg, free NH4^＋-N and NO3^--N concentration of leaf and root were determined at the 28th day treatments. Results showed that high NH4^＋ /NO3^- ratios （10：0, 9：1, 3：1） inhibited seedling growth, and the inhibition increased with NH4^＋-N. Cultivar Zhongzhi 13 showed more tolerance to NH4^＋ toxicity. Under NH4^＋-N/NO3^--N ratio at 1：9, seedlings exhibited the greatest plant biomass, and pH of nutrient solution maintained suitable especially for Zhongzhi 13. Compared with total NO3^--N treatment （0：10）, plant dry weigh, total root length and root surface area of Zhongzhi 13 were significantly increased 47%, 29% and 15% respectively. Moreover, appropriate NH4^＋-N/NO3^--N ratio promoted the absorption and utilization of N, P, K in Zhongzhi 13, as indicated by N, P, K concentrations increase in leaves and roots respectively. However, compared with total NO3^--N treatments （0：10）, ratio 1：9 was appropriate with no effect on plant biomass and nutrients uptake of Luo 12. Therefore, appropriate NH4^＋-N could enhance sesame seedlings biomass and root growth, NH4^＋-N/NO3^--N ratio of 1：9 was more suitable for growth and nutrient uptake of the seedling. It was recommended that NO3^--N could be used as a major N source for sesame, and suitable NH4^＋-N for specific sesame cultivars and soil was suggested in field.

关 键 词：芝麻(Sesamum indicum L.) 铵硝配比 生物量 根系形态 养分吸收 

分 类 号：S565.406[农业科学—作物学]