施氮量对云烟121上部烟叶代谢及品质的影响

Impact of Nitrogen Application Rate on Metabolism and Quality of Upper Leaves of Yunyan 121

为提高烤烟上部叶品质与可用性,筛选出曲靖烟区云烟121适宜的施氮量,分别施用纯氮82.5、105.0和127.5 kg·hm^(-2)进行大田试验,测定不同处理的农艺性状、上部成熟鲜烟叶的超微结构及烘烤后的外观质量、化学成分、感官质量等指标,并进行代谢组学分析,综合评价不同施氮量处理下云烟121的生长情况与上部烟叶品质。结果表明,3个施氮量处理烟株的长势无明显差异,其中105.0 kg·hm^(-2)处理烟株的综合发病率最低。随着施氮量的增加,云烟121上部叶片中的叶绿体降解减缓,淀粉粒与嗜锇颗粒体积增大,其中105.0 kg·hm^(-2)处理烟叶的嗜锇颗粒数量最多。施氮水平影响云烟121上部叶的代谢模式,且主要集中在莽草酸和苯丙烷代谢途径。在105.0 kg·hm^(-2)处理下,云烟121上部叶烤后的外观质量、化学成分、感官质量、经济性状均优于其他施氮水平。由此表明,施用纯氮105.0 kg·hm^(-2)能够有效提高曲靖烟区云烟121上部叶的品质与可用性。

To enhance the quality and usability of tobacco upper leaves,and screen suitable nitrogen application rate for Yunnan 121 in the Qujing tobacco-growing region,the field experiments were conducted with nitrogen application rates of 82.5,105.0 and 127.5 kg·hm^(-2).Agronomic traits were recorded under different treatments,the ultrastructure of mature upper tobacco leaves was examined,and the metabolomic was analyzed.After curing,the indicators such as external quality,chemical composition,sensory quality,etc.,were measured.The growth status and upper leaf quality of Yunnan 121 under different nitrogen application rates were comprehensively evaluated.The results showed that there was no significant difference on the growth of tobacco plants under 3 nitrogen application rate treatments,with the lowest comprehensive disease incidence observed in 105.0 kg·hm^(-2)nitrogen treatment.With increasing nitrogen application rates,the degradation of chloroplasts in the upper leaves of Yunnan 121 slowed down,and the volumes of starch granules and eosinophilic granules gradually increased,with the highest accumulation of eosinophilic granules of leaves in 105.0 kg·hm^(-2)nitrogen treatment.Nitrogen application levels influenced the metabolic patterns of upper leaves in Yunnan 121,primarily focusing on the pathways of oxalic acid and phenylpropane metabolism.Under the 105.0 kg·hm^(-2)nitrogen treatment,the post-curing appearance quality,chemical composition,sensory quality,and economic traits of upper leaves in Yunnan 121 were superior to the other 2 nitrogen application levels.Consequently,it should be considered that pure nitrogen of 105.0 kg·hm^(-2)could effectively improve the quality and usability of upper leaves in Yunnan 121 in the Qujing tobacco-growing region.