Table 2 SPAD values and plamochromic pigments in tobacco leaves inside and outside the greenhouse at various stages of flue-curing
From: Cold stress in the harvest period: effects on tobacco leaf quality and curing characteristics
Treatment | Sampling temperature (°C) | Continuous curing time (h) | SPAD | Chlorophyll a (μg g− 1) | Chlorophyll b (μg g− 1) | Lutein (μg g− 1) | β-carotene (μg g− 1) |
|---|---|---|---|---|---|---|---|
Inside the greenhouse | Fresh tobacco leaves | – | 36.2Aa | 286.06Aa | 202.99Aa | 150.30Ab | 1940.38Ab |
38 | 23.5 | 14.9Ab | 105.95Ab | 42.72Ab | 248.59Aa | 3657.98Aa | |
42 | 16.5 | 9.8Abc | 64.20Ab | 26.80Ab | 297.14Aa | 4127.06Aa | |
48 | 15 | 8.0Abc | 45.77Ab | 17.01Ab | 245.15Aab | 4489.59Aa | |
54 | 22.5 | 6.2Ac | 13.33Ab | 4.40Ab | 206.64Aab | 3524.01Aa | |
Initially flue-cured tobacco leaves | – | – | 43.75Ab | 17.42Ab | 249.00Aa | 3794.68Aa | |
Outside the greenhouse | Fresh tobacco leaves | – | 30.6Ba | 114.91Ba | 87.18Ba | 93.28Aa | 1207.53Aa |
38 | 23.5 | 13.4Ab | 13.37Aa | 7.94Ab | 118.40Ba | 1573.64Ba | |
42 | 16.5 | 9.5Abc | 5.12Aa | 3.68Ab | 112.31Ba | 1669.27Ba | |
48 | 15 | 7.8Abc | 4.83Aa | 3.50Ab | 115.36Ba | 1800.61Ba | |
54 | 22.5 | 3.0Ac | 3.88Aa | 2.53Ab | 139.42Aa | 1888.94Ba | |
Initially flue-cured tobacco leaves | – | – | 6.74Aa | 4.83Ab | 122.23Ba | 1783.31Ba |