Forage yield and survival of native range species under supplementary irrigation in Central Saudi Arabia

Abstract

The increase of livestock production in Saudi Arabia has resulted in a parallel increase in demand for forage production and hence greater exploitation of ground water for irrigation. The current trend of water conservation policies necessitates finding alternate sources of forages that consume less water than the traditional forage crops. The objective of this study was to evaluate the forage yield and survival of some range species under certain levels of supplementary irrigation. The evaluated species were Atriplex halimus , Atriplex leucoclada, Farsetia aegyptia, Salsola villosa and Artemisia sieberi. The supplementary irrigation treatments were: yearlong irrigation with an amount of 480 mm water, summer and fall irrigation (240 mm), summer irrigation (120 mm) and no supplementary irrigation. Results showed that supplementary irrigation of native range species during summer season increased yield by more than 3-fold over the rain-fed stand. This increase was associated by improvement in the plant survival. Of the five species evaluated, the two saltbushes A. halimus and A. leucoclada produced exceptionally high yield. This study suggested that there is a great potential for the use of native range species as efficient alternatives for the high water demanding traditional forages in arid regions. Key words: Forage yield, range plants, supplementary irrigation. INTRODUCTION It is estimated that about 216,000 ha of agricultural lands in Saudi Arabia are currently cultivated with forage crops, producing nearly 326,000 tons per year (Ministry of Agriculture and Water, 2002). The main forage crops are alfalfa and rhodesgrass. The most important limitation to forage crop production is their high demand for the already scarce water resources. With incessant increase in demand for red meat, the demand for forage production will continue to increase. It is estimated that average national demand from alfalfa and rhodesgrass is over 2 million tons/ year (Alabdulkader et al., 2012). It is estimated that alfalfa requires 30,000 to 37,000 m