Evaluation of Yield and Nutritional Value of Fodder Crops under Plastic Greenhouse Structure

Abstract

One of the challenges in arid and semi-arid regions, such as Iran, for fodder supply is water scarcity and poor quality. There are various strategies for producing fodder using less water. One of these is forage production under greenhouse conditions (plastic cover). This issue is also significant because the production of common greenhouse plants such as cucumbers and tomatoes is no longer profitable in many greenhouses due to an increase in their irrigation water salinity. To evaluate the feasibility of fodder production under greenhouse conditions, a study was conducted in Yazd, Iran, from 2022 to 2023. Crops were sorghum, corn, pearl millet, guar, amaranth, lathyrus, hairy vetch, fodder beet, and safflower. Fodder fresh and dry weight, plant height, and water productivity, as well as crude protein, starch, acid detergent fiber, and neutral detergent fiber, were measured. Results showed that amaranth could produce about 74.1 Mg ha^-1 fresh weight in 35 days. The mean fodder fresh weight for safflower and fodder beet was 93.6 and 238.1 Mg ha^-1, respectively. The fresh and dry weight of fodder for sorghum during the year was 650 and 117 Mg ha^-1, respectively; at least 5 times more than it in field conditions. The highest fresh weight was obtained for corn, Chavosh cv., by 105 Mg ha^-1. The values of crude protein for sorghum, corn, hairy vetch, and amaranth were 10.7, 8.3, 21.9, and 21.0% of dry matter. The water consumption in greenhouse conditions was also about 30-36% of the field conditions. Results of the study showed that in arid and semi-arid areas, it is possible to provide the required fodder in plastic greenhouses with less water consumption.