Irrigation Water Management of Horticultural Crops

Abstract

WP by increasing yield and/or reducing ET always results in net savings, thus reducing agricultural water requirements. This is a key point in assessing the opportunities for true water savings in horticultural crop cultivation and will be addressed in detail later in this paper.Water productivity in irrigated agriculture varies widely and depends on many biophysical and management factors. Because variations in ET among crops are within an order of magnitude apart, by far the most important factor infl uencing WP is the economic value of the product. Horticultural products are usually high value and thus WP normally exceeds that of fi eld and row (agronomic) crops. For example, using current values for yield and ET characteristic of California agriculture, the WP of corn is about 0.20 $/m 3 , compared to 0.70 $/m 3 for almond, 5.00 $/m 3 for strawberry, and even more for greenhouse and ornamental crops. An extreme example of this occurs with vegetable crops grown under plastic in southeast Spain during the off-season. The combination of high market prices and low ET leads to a WP of about 10 $/m 3 . While impressive, even this value cannot compete with that of industrial and urban uses. Nevertheless, it helps explain the trend of shifting irrigated acreage from low value fi eld and row crops to horticultural crops in many water-scarce areas of the US, a trend that will probably increase worldwide (National Research Council, 1996). Indeed, the WP of an irrigation district in Southern Spain increased over a four year period as the proportion of horticultural crops increased (I. Lorite, L. Mateos, and E. Fereres, unpublished data).This paper describes the evolution of water use as related to productivity with an emphasis on the U.S. experience, analyzes how irrigation systems and management have evolved since the early 1900s, and explores the challenges and opportunities for water conservation in horticulture. Because of the broad scope of the subject and limited space, the paper focuses primarily on tree crops although many principles are applicable to all horticultural crops.

Virgin olive oil and olive fruit minor constituents as affected by irrigation management based on SWP and TDF as compared to ETc in medium-density young olive orchards (Olea europaea L. cv. Cornicabra and Morisca)

“…Moreover, the estimation of the ET c parameter used by the FAO methodology is subjected to great uncertainties related to meteorology and olive crop characteristics (load level, crop age, olive tree vegetative stage, etc.) (Fereres, Goldhamer, & Parsons, 2003;Naor, 2003). Therefore, the use of irrigation scheduling based on the direct measurements of olive tree water status seems to be a suitable alternative to determine the irrigation doses to be applied in the orchard.…”

A survey of Lolium rigidum populations in citrus orchards: Factors explaining infestation levels

“…In addition, drip irrigation optimises the efficiency of fertilizers that are applied by direct injection (Fereres et al . ).…”

“…Drip irrigation increases water and fertilizer use efficiency by using localized irrigation, allowing better field access for equipment and decreasing the spread of weeds (Fereres et al . ). The frequency of fertilization depends on the irrigation system.…”

The Relationship Between Soil Water Potential, Environmental Factors, and Plant Moisture Status for Poblano Pepper Grown Using Tensiometer-Scheduled Irrigation

“…Although these factors are important variables in ET and plant hydraulic conductivity models (Farahani et al, 2007), they are not always closely correlated to changes in L (Sranaga et al, 1991). Fereres et al (2003) noted that atmospheric factors affecting transpiration are closely related to changes in plant water status in cropping systems where canopies are strongly coupled to their environments, such as orchards, which have tall uneven canopies. However, vegetable crops, such as peppers, have short, smooth canopies that are often poorly coupled to their surrounding atmosphere, resulting in poor correlations between atmospheric variables and transpiration (Jarvis and McNaughton, 1986).…”