Agriculture Reference
In-Depth Information
peppers, beet palak and tomatoes are moderately sensitive to salin-
ity. One of the most effective ways to overcome salinity problems
is the use of tolerant species and varieties (Yilmaz et al., 2004). The
response of plants to increasing salt application may differ signifi-
cantly among plant species as a function of their genetic tolerance.
8.3.11.4
WATER MANAGEMENT
Since vegetables contain very high amount of water and many vegetables
are eaten raw, therefore use of quality water remains a major concern
.
The quality and efficiency of water management determine the yield and
quality of vegetable products. Too much or too little water causes ab-
normal plant growth, predisposes plants to infection by pathogens, and
causes nutritional disorders. If water is scarce and supplies are erratic or
variable, then timely irrigation and conservation of soil moisture reserves
are the most important agronomic interventions to maintain yields dur-
ing drought stress. There are several methods of applying irrigation water
and the choice depends on the crop, water supply, soil characteristics and
topography. Surface irrigation methods are used in more than 80% of the
world's irrigated lands yet its field level application efficiency is often
40-50% (Von et al., 2004). To generate income and alleviate poverty of
the small-holder farmers, promotion of affordable, small-scale drip irriga-
tion technologies are essential. Drip irrigation minimizes water losses due
to run-off and deep percolation and water savings of 50-80% are achieved
when compared to most traditional surface irrigation methods. Crop pro-
duction per unit of water consumed by plant evapo-transpiration is typi-
cally increased by 10-50%. Thus, more plants can be irrigated per unit of
water by drip irrigation, and with less labor. The water-use efficiency by
chili pepper was significantly higher in drip irrigation compared to fur-
row irrigation, with higher efficiencies observed with high delivery rate
drip irrigation regimes (AVRDC, 2005). For drought tolerant crop like
watermelon, yield differences between furrow and drip irrigated crops
were not significantly different; however, the incidence of Fusarium wilt
was reduced when a lower drip irrigation rate was used. In general, the
use of low-cost drip irrigation is cost effective, labor-saving, and allows
more plants to be grown per unit of water, thereby both saving water and
increasing farmers' incomes at the same time.
