Geha Foods Evaluation of Irrigation for Processed Tomatoes

opportunity present itself to minimize any water stress. With irrigation the penalties for
under irrigating and stressing the crop are substantially greater then the penalties for over
irrigating. Please don’t blame the farmers for logical choices with an unreliable delivery
system.
Water Charges: There is an effort to charge farmers for use of irrigation water. This is
proclaimed as a volume charge but no water is actually measured. Instead it would be more
accurately called an area by crop charge, and assumes the crop only receives the estimated
water duty for that crop. Without actually measuring the water, an estimated volume charge
is not effective in reducing excess water use, if that is part of the purpose. Trying to manage
a true measured volume charge can tremendously increase the administrative cost and
become a major financial burden to the farmers, particularly smallholders. However, in
Tajikistan collections are difficult, and if you are making informal payments to secure water,
you are reluctant to make formal payments. Unless, of course, the opposite is happening, and
the informal payment is in lieu of assessed charges. The end result is no funds for necessary
maintenance work on the main diversion and canal system. Since the government appears to
be making substantial profit from cotton sales, a portion of which represents a depressed farm
gate cotton price, the depressed cotton prices could be viewed as a rural tax, and part of the
revenue gained be allocated for irrigation infrastructure maintenance, and in reality this is a
easy form of taxation or water user fees to collect.
Overview
Improving Irrigation for Processing Tomatoes, etc.
Before reviewing the different possibilities for improving the irrigation system for processed
tomatoes in conjunction with other crops, it might be desirable to review a couple points in
advance.
Multiple Crops Involved: First, it appears the tomatoes will not be produced alone but most
likely produced along side of Cotton, with most of the public sector support services focused
on cotton. Tomato production could actually benefit from the excessive government emphasis
on cotton with depressed returns, as inputs usually get favorable diverted from the less
economic to the more economic crop. Thus any renovations to the irrigation system at the
farm level will have to consider both crops and the probability of rotating between them, as
well as other crops like winter wheat, potatoes, vegetables, etc. This rotation with other crops
might be important in controlling some of the soil borne diseases of tomatoes such as late
blight. Renovating the irrigation system for both tomatoes and cotton should not be a major
problem as both are furrow irrigated with tomatoes usually grown on beds approximately
twice the width of cotton furrows. Thus most likely it would be possible to grow cotton on
tomato beds using two rows per bed instead of one.
Evapotranspiration Energy: Also, the other problem is that the water requirements are
reasonable similar for all crops during the balk of the growing season. This is because the
water requirements of different crops are more an external climatic factor, than an individual
plant factor. This is really basic physics as transpiration represents a change in state of water
from the liquid to vapor state. This is referred to as the latent heat of evaporation and
requires some 536 cal/cc of water. This energy is not available from within the plant. It
really comes from direct solar radiation and consumes most of the solar radiation reaching the
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