施氮量对四川雪茄烟叶碳氮代谢及品质的影响

为探究施氮量对雪茄烟叶生长过程中碳氮代谢及调制后烟叶品质的影响,以德雪1号为试验材料,分析了不同施氮量（120、165和210kg/hm²,分别记为T1、T2和T3处理）对雪茄烟叶生长期间碳氮代谢关键酶活性、质体色素以及调制后化学成分含量、物理特性和感官质量的影响。结果表明,在雪茄烟叶生长过程中,各处理烟叶淀粉酶（AL）、中性转化酶（NI）、硝酸还原酶（NR）、谷氨酰胺合成酶（GS）活性以及淀粉含量均呈先升高后降低的趋势,总氮含量呈下降趋势。随着施氮量的增加,不同时期鲜烟叶AL、NI、NR和GS活性均有所升高,淀粉含量降低,总氮含量升高。烟叶成熟时,T3处理叶片叶绿素和类胡萝卜素含量较T1处理分别增加了41.71%和21.31%,不利于烟叶成熟落黄。从调制后烟叶化学成分来看,T2处理的烟叶氮碱比较低而钾氯比较高,内在化学成分较协调,拉力和平衡含水率较高,含梗率较低,物理特性较好,香气质、香气量以及燃烧性等指标的分值较高,感官质量较优。因此,四川什邡雪茄烟种植区采用165kg/hm²的施氮量有利于提高烟叶碳氮代谢能力,改善烟叶内在品质,提高烟叶可用性。

Effects of Nitrogen Application Rates on Carbon and Nitrogen Metabolism and Quality of Cigar Leaves in Sichuan

In order to explore the effects of nitrogen application rate on the carbon and nitrogen metabolism during the growth of cigar leaves and the quality of tobacco leaves after airing. Taking Dexue No.1 as the experimental material, the effects of different nitrogen application rates (120, 165 and 210kg/ha, represented in T1, T2 and T3) on the key enzyme activities of carbon and nitrogen metabolism and plastid pigments during cigar leaves growth, and chemical composition, physical characteristics and sensory quality of cigar leaves after airing were analyzed. The results showed that, during the growth of cigar leaves, the activities of amylase (AL), neutral invertase (NI), nitrate reductase (NR), glutamine synthetase (GS) and the content of starch all increased first and then decreased under different treatments, but the content of total nitrogen showed a downward trend. With the increase of nitrogen application rate, during different measurement periods, the activities of AL, NI, NR, GS and the contents of total nitrogen of tobacco leaves increased, while the starch content decreased. Compared with T1 at mature stage, the contents of chlorophyll and carotenoid of T3 treatment increased by 41.71% and 21.31%, respectively, which was harmful to the normal metabolism of carbon-nitrogen and tobacco maturing. The nitrogen-nicotine ratio of T2 treatment was lower and potassium-chlorine ratio was higher, and the chemical components were suitable, the pull and equilibrium moisture content were higher, the stem ratio was lower, and the physical characteristics were good, the scores of aroma quality, aroma volume and combustibility were higher, and the sensory quality was good. Therefore, the suitable nitrogen application rate for cigar leaves was determined to be 165kg/ha in Shifang, Sichuan province. It was conducive to increase the carbon and nitrogen metabolism capacity and improve the quality of cigar leaves.