PERFORMANCE OF GRAPEVINES UNDER IRRIGATION SYSTEMS - Management, Performance, and Applications of Micro Irrigation Systems - page 269

system and to check the system components will depend on irrigation duration, which
can be different for each irrigation system according to the irrigation application rate.
Labor cost was estimated with Eq. (16). Energy cost was calculated with the Eq. (17).
Total annual irrigation cost was the total sum of fi xed cost and operating cost.

L.C = T2 × N × P (16)

E.C = Bp × T3 × Pr (17)

where: L.C = annual labor cost, LE/year; T2 = annual irrigation time, hours/year; N =
number of farm workers per feddan; P = labor cost, LE/hour; E.C. = energy cost, LE/
year; Bp = the brake power, kW; T3 = annual operating time, hours; and Pr = cost of
electrical power, LE/kW-hour.
Fertilization process was carried out by fertigation under drip and low-head bub-
bler and modifi ed surface irrigation by using gated pipes irrigation for ammonium
sulfate and potassium sulfate and using the traditional method (top dressing) for super-
phosphate. Fertilization cost was calculated with the Eq. (18). Pest control was carried
with the sprayer. Pest control cost was calculated with the Eq. (19). Weed control was
manual and weed control cost was calculated with the Eq. (20).

Fr = (Wf × Pr) + Ac (18)

Pc = (Wp × P) + Ac (19)

Wc = N × L × T4 (20)

where: Fr = fertilization cost, LE/fed; Wf = amount of fertilizers, kg/fed; Pr = fertil-
izers price, LE/kg; Ac = application cost of fertilizers, LE/fed; Pc = pest control cost,
LE/fed; Wp = amount of pesticides, kg/fed; P = pesticides price, LE/kg; Wc = weed
control cost, LE/fed; N = number of farm workers per faddan; L = labor cost, LE/hour;
and T4 = time used, hours/fed.
The net profi t of grapevines for each irrigation system was calculated with Eq. (21)
[88]. The production cost (LE/kg) was estimated with the Eq. (22).

P = (Yt × d) - Ct (21)

LE/kg = (Total cost in LE/fed)/(Total yield in kg /fed) (22)

where: P = net profit, LE/fed; Yt = total yield, tons/fed; d = market price, LE/ton (It
was assumed as 1250 LE for each one ton of grape); Ct = total production costs, LE/
fed.

20.2.7 STATISTICAL ANALYSIS
The statistical analysis was conducted for all collected data for analysis of variance
(ANOVA) and the least significant difference (L.S.D) among the irrigation systems at
5%. The randomized complete block design [21] was used for the experimental setup.