Effects of different planting densities and numbers of remaining leaves on components of chromoplast pigment and its degraded products in flue-cured tobacco leaf.

The effects of different planting densities and numbers of remaining leaves on the contents of chromoplast pigment and its degradation products of flue-cured tobacco leaves were studied in Nanyang of Henan Province.A tobacco(Nicotiana tobacum L.)cultivar Yunyan 87 was selected as the material.The results showed that the effects of different planting densities,numbers of remaining leaves and their interaction on the contents of chromoplast pigment and its degraded products of flue-cured tobacco leaves were significant.Chromoplast pigment and its degraded products firstly increased then decreased with the increase in planting density.In the treatment in which 22 leaves per plant were remained,the contents of chlorophyll a,chlorophyll b,total chlorophyll and carotenoid reached 0.020 2 mg/g,0.015 7 mg/g,0.035 9 mg/g and 0.365 8 mg/g,respectively,which were the highest among the treatments of different numbers of remaining leaves.In the treatment in which the cultivar was planted at the row spacing of 120 cm×55 cm and 22 leaves per plant were remained,the contents of degraded products of chlorophyll and carotenoid were the highest among the tratments of the interaction of planting densityand number of remaining leaves,which were 1 071.000 0 μg/g and 64.17 μg/g,respectively,accounting for 87.54% and 5.25% of aroma contents,respectively.