Table 3 Effects of light sources on total leaf thickness, length of palisade parenchyma cells, length of spongy layer as well as thickness of adaxial and abaxial epidermis, and ratio of palisade to spongy tissue. Values are means of 5 replicates ± standard deviation (SD). Means in the same column with different letters differ significantly (p < 0.05)

LED 1

211.43 ± 8.19 a

67.43 ± 2.22 bc

102.77 ± 4.65 a

22.18 ± 0.68 bc

19.48 ± 1.05 a

0.66 ± 0.03 c

LED 2

171.60 ± 10.25 c

90.44 ± 3.61 a

51.12 ± 1.03 c

20.27 ± 2.07 c

8.78 ± 0.95 c

1.78 ± 0.15 a

LED 3

189.20 ± 1.71 b

63.37 ± 3.15 c

88.39 ± 4.14 b

20.32 ± 1.04 c

15.56 ± 1.78 b

0.72 ± 0.04 c

LED 4

191.38 ± 4.81 b

72.56 ± 3.15 b

81.02 ± 1.40 b

29.22 ± 2.95 a

17.14 ± 0.82 b

0.91 ± 0.06 b

HPS

206.54 ± 6.08 a

63.76 ± 2.13 c

102.54 ± 6.45 a

24.91 ± 2.05 b

16.60 ± 1.22 b

0.62 ± 0.04 c