Table 3 Leaf chlorophyll index and total protein of common bean as a function of plant growth-promoting bacteria and nano-Zn foliar doses in 2019 and 2020 cropping seasons

Inoculations (I)

Control (no-inoculation)

32.2 ± 3.6 b

33.0 ± 3.1 b

164.2 ± 22.0 c

168.2 ± 19.2 b

R. tropici

36.2 ± 7.9 a

35.3 ± 4.7 a

189.3 ± 17.9 a

195.5 ± 13.0 a

R. tropici + A. brasilense

34.9 ± 5.4 a

36.3 ± 4.4 a

191.0 ± 12.5 a

191.3 ± 15.6 a

 R. tropici + B. subtilis

37.6 ± 3.6 a

38.0 ± 1.9 a

184.73 ± 11.6 a

195.53 ± 8.9 a

R. tropici + P. fluorescens

37.4 ± 2.7 a

36.7 ± 2.3 a

183.5 ± 8.9 a

192.6 ± 8.0 a

R. tropici + A. brasilense + B. Subtilis

35.0 ± 4.9 a

36.0 ± 2.5 a

175.5 ± 9.9 b

189.7 ± 11.1 a

 R. tropici + A. brasilense + P. fluorescens

36.3 ± 2.9 a

35.4 ± 2.6 a

182.8 ± 8.2 a

194.6 ± 9.0 a

Nano-Zn foliar spray (kg ha⁻¹)

0.0

31.4 c

33.1 c

178.8 a

183.9 c

1.5

38.9 a

38.0 a

184.3 a

195.2 a

3.0

36.6 b

36.4 b

181.6 a

189.9 b

F values

 I

3.8*

5.04**

7.02**

23.17**

 Nano-Zn

37.4**

31.4**

1.51^ns

18.34**

 I × nano-Zn

0.85^ns

0.58^ns

0.12^ns

2.04^ns

CV (%)

9.4

6.6

6.6

3.79