密度和施氮量互作对烤烟叶片组织结构的影响

摘要

为探究种植密度和施氮量对烤烟中部叶片组织结构的影响,以烤烟品种NC102为材料,采用裂区设计,以种植密度为主区,施氮量为副区,在大田条件下分别采集10、20、40和73 d叶龄的中部叶片,制作石蜡切片并观察组织结构.结果表明,叶片厚度、栅栏组织厚度、海绵组织厚度、叶面积随叶龄增加均增加,栅栏细胞密度反之.随种植密度的降低和施氮量的提高,叶片厚度、栅栏组织厚度、海绵组织厚度、叶面积、比叶重均增加,栅栏组织密度降低.施氮量对栅栏细胞密度的影响早于种植密度,对栅栏组织厚度的影响晚于种植密度.73 d时叶片厚度、栅栏组织厚度、组织比、叶面积、比叶重受低种植密度和高施氮量的正交互作用影响,密度越低,施氮量增加对叶片组织结构的影响更加显著.在一定范围内,适当调节种植密度和施氮量,利用其交互作用,可以改善叶片结构,达到优质适产的目的.%To investigate the interaction effects of different planting density and nitrogen (N) application amount on tobacco leaf development and tissue structures, a split-plot field experiment with three different planting densities (main district) and two different N application amounts (deputy district) was carried out using the cultivar NC102. Through paraffin section method, the tissue structure of middle leaves with different leaf ages (10, 20, 40 and 73 d) were observed. The results showed that leaf thickness, palisade tissue thickness, spongy tissue thickness and leaf area increased with leaf aging, but palisade cell density decreased. Leaf thickness, palisade tissue thickness, spongy tissue thickness, leaf area and specific leaf weight increased but palisade cell density decreased with the decrease of planting density and increased N application rate. The action time of N application amount on palisade cell density was earlier than that of planting density, while the timing of effects of these two treatments was the opposite for palisade tissue thickness. There was a positive interaction between low planting density and high N application amount on leaf thickness, palisade tissue thickness, ratio of palisade tissue thickness and spongy tissue thickness, leaf area and specific leaf weight when leaf age was 73 d. The increase of N application amount showed more significant impact under lower planting densities. Adopting appropriate planting density and N application amount and taking advantage of their interaction could improve tissue structures of middle leaves and ultimately improve the quality of tobacco under proper yield.