Boron, Copper, and Zinc Affect the Productivity, Cup Quality, and Chemical Compounds in Coffee Beans

Table 2

Contents of B, Cu, and Zn (mg·kg⁻¹) of index leaves of coffee plants that received B, Cu, and Zn as solid injections or foliar sprays (FSs).

Crop season	2010/2011	2011/2012
Boron
WB	24.08	27.46
FS (control)	35.04	30.35
B	35.51	50.41^,
B + Cu	35.04	64.65^,
B + Zn	33.26	72.31^,
B + Cu + Zn	23.94	78.64^,
CV (%)	6.59	13.19
Copper
WCu	9.64	5.24
FS (control)	13.51	13.14
Cu	17.06^,	18.62^,
B + Cu	14.94	15.79^,
Cu + Zn	18.96^,	19.41^,
B + Cu + Zn	16.46^,	16.52^,
CV (%)	8.25	6.15
Zinc
WZn	6.5	4.68
FS (control)	10.06	7.42
Zn	10.85	11.58^,
B + Zn	10.63	10.89^,
Cu + Zn	11.75^,	13.66^,
B + Cu + Zn	9.85	9.98^,
CV (%)	6.25	16.31

WB, WCu, and WZn: control treatments, without application of B, Cu, and Zn, respectively; FS: foliar spray with boric acid, copper sulphate, and zinc sulphate (0.4%); B: trunk injection of tablets containing B salts; Cu: trunk injection of tablets containing Cu salts; Zn: trunk injection of tablets containing Zn salts; B + Cu: trunk injection of tablets containing B and Cu salts; B + Zn: trunk injection of tablets containing B and Zn salts; Cu + Zn: trunk injection of tablets containing Cu and Zn salts; B + Cu + Zn: trunk injection of tablets containing B, Cu, and Zn salts; mean values are statistically different from those of the control treatment (FS) at the 10% significance level, according to Dunnett’s test; mean values are statistically different from those of the control treatment (WB-WCu-WZn) at the 10% significance level, according to Dunnett’s test.