Comparison of chlorophyll content in greenhouse tomato and cucumber leaves after HBED-Fe and EDDHA-Fe applications

Figures & data

Table 1. Application distribution.

Greenhouse	Module	Details	Number of rows	Number of applications	Application dates^a
C	C1	Control	5	0	–
	C2	EDDHA-Fe	5	3	+26; +51;+78
	C3	HBED-Fe	5	3	+16;+41; +68
	C4	HBED-Fe	5	2	+11; +57
	C5	HBED-Fe	3	1	−10
T	T1	Control	5	0	–
	T2	EDDHA-Fe	5	3	+31; +70; +115
	T3	HBED-Fe	5	3	+21; +60; +105
	T4	HBED-Fe	5	2	+20; +80
	T5	HBED-Fe	4	1	−10

Notes: C1, C2, C3, C4 and C5 are cucumber modules and T1, T2, T3, T4 and T5 are tomato modules.

1, control module without any application; 2, EDDHA-Fe fertilizer applied three times during the crop cycle; 3, HBED-Fe fertilizer applied three times during the crop cycle; 4, HBED-Fe fertilizer applied two times during the crop cycle; 5, HBED-Fe fertilizer applied one time during the crop cycle.

^aDays of application before (−) and after (+) plantation.

Table 2. Sampling campaigns.

	Plantation	Sampling 1	Sampling 2	Sampling 3
Tomatoes	3/29/2014	+50 d	+98 d	–
Cucumbers	4/4/2014	+45 d	+75 d	+96 d

Table 3. Results of soil analyses.

Sample	SC	ST
pH	7.5 ± 0.1	7.5 ± 0.2
Iron (g/kg)	34.4 ± 5.2	39.6 ± 2.7
Conductivity (mS/cm)	0.5 ± 0.2	0.5 ± 0.4
Total limestone (%)	2.0 ± 0.8	2.6  ± 1.5
Active limestone	0.5 ± 0.2	0.5 ± 0.1
Organic matter (%)	1.9 ± 0.1	2.7 ± 0.3
Sand	49% ± 8	57% ± 8
Silt	25% ± 0	24% ± 3
Clay	26% ± 8	19% ± 7

S_C,  Soil samples from the cucumber greenhouse; S_T, soil samples from the tomato greenhouse.

Figure 1. Average chlorophyll concentration in (a) cucumber leaves and (b) tomato leaves. C is for cucumber modules and T is for tomato modules. 1, 2, 3, 4 and 5 are the five different modules studied. 1, control module without any application; 2, EDDHA-Fe fertilizer applied three times during the crop cycle; 3, HBED-Fe fertilizer applied three times during the crop cycle; 4, HBED-Fe fertilizer applied two times during the crop cycle; 5, HBED-Fe fertilizer applied one time during the crop cycle.*Means with the same letter are not significantly different (p < .05).

Table 4. Results of leaf analyses for cucumber crops.

Chlorophyll (µg/mL) mean ± standard deviation
	Sampling 1	Sampling 2	Sampling 3
C1	14.710 ± 2.532^a	17.966 ± 2.164^a	18.661 ± 3.497^a
C2	15.106 ± 2.118^a	20.748 ± 3.997^b	19.552 ± 3.929^a
C3	18.707 ± 3.016^b	21.642 ± 1.259^b	23.856 ± 2.852^b
C4	18.513 ± 3.216^b	21.402 ± 3.756^b	18.730 ± 1.561^a
C5	19.184 ± 3.445^b	21.946 ± 1.874^b	18.365 ± 3.829^a

Notes: 1, control module without any application; 2, EDDHA-Fe fertilizer applied three times during the crop cycle; 3, HBED-Fe fertilizer applied three times during the crop cycle; 4, HBED-Fe fertilizer applied two times during the crop cycle; 5, HBED-Fe fertilizer applied one time during the crop cycle.

Means with the same letter are not significantly different (p < .05).

Table 5. Results of leaf analyses for tomatoes.

Chlorophyll (µg/mL) mean ± standard deviation
	Sampling 1	Sampling 2
T1	20.711 ± 3.678^a	19.470 ± 2.197^a
T2	20.969 ± 2.707^a	23.178 ± 2.552^b
T3	21.517 ± 3.763^ac	26.116 ± 3.421^c
T4	26.221 ± 3.252^c	21.265 ± 4.174^ab
T5	23.321 ± 4.559^b	20.114 ± 3.651^a

Notes: 1, control module without any application; 2, EDDHA-Fe fertilizer applied three times during the crop cycle; 3, HBED-Fe fertilizer applied three times during the crop cycle; 4, HBED-Fe fertilizer applied two times during the crop cycle; 5, HBED-Fe fertilizer applied one time during the crop cycle.

Means with the same letter are not significantly different (p < .05).

Figure 2. Availability of HBED-Fe in the soil.