Evaluation of irrigation scheduling to maximize tomato production using comparative assessment of soil moisture and evapotranspiration in restricted irrigated regions

Figures & data

Figure 1. Location map of the study area.

Figure 2. Climate data of the study area.

Figure 3. Layout of experimental field.

Note: T1, T2, T3, T4, T5 and T6 = Total treatments, T1, T2 and T3 = SM-based represented for 100%, 75% and 50% of requirement and T4, T5 and T6 = ET-based represented for 100%, 75% and 50% of requirement. R represents rows (Replications).

Figure 4. Soil infiltration test carried out in the field.

Figure 5. Infiltration test graph.

Table 1. Treatments and levels of application

Plots	Application level	Plots	Application level
ST1R1	100%	ET4R1	100%
ST1R2	100%	ET4R2	100%
ST1R3	100%	ET4R3	100%
ST2R1	75%	ET5R1	75%
ST2R2	75%	ET5R2	75%
ST2R3	75%	ET5R3	75%
ST3R1	50%	ET6R1	50%
ST3R2	50%	ET6R2	50%
ST3R3	50%	ET6R3	50%

S and E are for SM- and ET-based methods, respectively; T is treatment; R is replication; 100%, 75%, and 50% are deficit levels.

Figure 6. RBC flume and b) discharge measurement.

Figure 7. The relationship between RBC flume discharge (l/sec) and head (mm).

Table 2. Soil properties of the area

Depth cm	Sand,, %	Silt, %	Clay, %	Texture	Bulk density, g/cm^3	FC, %	PWP, %	pH	EC, dS/m
0–20	28	31	41	Clay	1.11	38.71	20.13	7.29	2.46
20–40	30	27	43	Clay	1.13	34.30	19.50	7.31	2.03
40–60	22	34	44	Clay	1.15	31.52	17.20	7.30	1.93
Average	26.67	31.33	42	Clay	1.13	34.84	18.94	7.30	2.14

Table 3. Irrigation schedules

		SM-based			ET-based
No. of Ir	Date of Ir	Inet (mm)	Ig(mm)	Date of Ir	Inet (mm)	Ig (mm)
Ir 1	21-Jun	12.4	19.0	21-Jun	12.4	19.0
Ir 2	27-Jun	12.1	18.7	27-Jun	12.3	18.9
Ir 3	03-Jul	13.7	21.2	03-Jul	12.4	19.0
Ir 4	13-Jul	18.0	27.6	12-Jul	15.4	23.7
Ir 5	20-Jul	23.7	36.4	23-Jul	19.2	29.5
Ir 6	02-Aug	25.6	39.3	06-Aug	30.3	46.6
Ir 7	09-Aug	27.6	42.4	18-Aug	32.4	49.8
Ir 8	20-Aug	28.5	43.9	24-Aug	34.2	52.6
Ir 9	27-Aug	30.5	47.0	03-Sep	36.1	55.5
Ir 10	09-Sep	37.1	57.0	11-Sep	37.2	57.2
Ir 11	-	-	-	19-Sep	38.4	59.1
	Sum	229.1	352	Sum	280	430.9

Ir is irrigation, Inet is net irrigation, Ig is gross irrigation, and Dates are on Gregorian calendar.

Figure 8. SM variations in scheduling methods.

Figure 9. Net irrigation comparison for scheduling method.

Table 4. Net requirement of irrigation water

Treatments	NIR (mm)	GIR (mm)
T1	229.1	352.5
T2	171.8	264.4
T3	114.6	176.2
T4	280.0	430.9
T5	208.5	323.2
T6	139.0	215.5

*T1, T2, and T3 are for treatment one, two, and three, respectively.

Table 5. ANOVA for effects of irrigation scheduling methods on WUE

Treatment	CWUE (kg/m^3)	IWUE (kg/m^3)	FWUE (kg/m^3)
T1	15.4^c	17.9^b	11.6^b
T2	18.5^a	22.5^a	14.6^a
T3	16.6^b	22.0^a	14.3^a
T4	11.6^e	14.5^c	9.5^c
T5	13.5^d	18.2^b	11.8^b
T6	11.5^e	17.4^b	11.3^b
CV	2.61	2.6	2.5
LSD	0.312	0.399	0.249

* Similar spellings indicate the non-significant difference between the means

Table 6. ANOVA for the effect of irrigation scheduling methods on yield performance

Treatment	Total yield (ton/ha)
T1	42.70^a
T2	41.87^a
T3	29.40^b
T4	42.50^a
T5	41.63^a
T6	28.90^b
CV	2.71
LSD	0.943

Similar spellings indicate the non-significant difference between means