Introduction
Considering the role of fodder crops in providing protein and dairy materials, and ensuring the country’s food security, as well as the significant import of various livestock inputs, increasing the productions of the fodder crops are necessary. Due to its adaptability to different climates, high yield and nutritional value, and ease of digestion, corn is one of the most important sources of poultry and livestock feed (Mohageri et al., 2015; Seif et al., 2019; Behrouzi et al., 2022). Yazd province is notable for its significant agricultural production in greenhouse crops. The area of greenhouses in the province is about 2,100 hectares. Currently, there are greenhouses in the province that are not economical for producing common greenhouse plants such as tomato and cucumber. These greenhouses could be used for fodder production. Additionally, fodder crops could be planted in late spring and summer when the greenhouses are empty. This research was conducted to determine fodder quantity and quality of corn cv. Dehghan at different planting dates in greenhouse.
Materials & Methods
To investigate the production of corn fodder under greenhouse conditions, two separate experiments were conducted using a completely randomized design with four replicates in Yazd province during 2021-2023. The aim of the first experiment was determining feasibility of fodder corn production in the greenhouse conditions, by comparing Dehghan and SC704 cultivars. The second experiment focused on assessing the response of the Dehghan cultivar to different planting dates in the greenhouse. This experiment included five planting dates: August 7 and October 12 2021, and January 29, February 27, and April 17, 2022. Planting density was 100000 plants per hectare. Irrigation was initiated immediately after planting. The greenhouse irrigation schedule was as follows; every other day from June to October, once every four days in November and December, once every six days in January and February, and once every three days from March to May. To supply the required nutrients, urea, calcium nitrate and monopotassium phosphate were applied with the irrigation rates of 40, 1.3 and 1.3 kg per 1000 m2 of corn greenhouse, respectively. During the growing season, heating systems were used only in December, January and February, maintaining a night temperature of 25°C. Corn was harvested on the planting dates of August 7 and October 12 2021, January 29, February 27, and April 17, 2022, in 84, 137, 77, 91, and 80 days after planting, respectively. Data were analyzed using SAS software, and mean comparisons were performed using the FLSD test at the 5% probability level.
Results & Discussion
Results of the first experiment showed that the fresh and dry fodder yield for the SC704 (88.12 and 19.02 t h-1, respectively) was significantly higher than that of the Dehghan cultivar (80.05 and 16.09 t h-1, respectively). However, cob index as an important nutritional value for ensiling, in Dehghan cultivar was significantly higher than that of the SC704 by 49%. The protein, starch, NDF (natural detergent fiber) and ADF (acid detergent fiber) content of the Dehghan cultivar forage was 8.33, 25.05, 23.75 and 46.9%, respectively in greenhouse conditions. Compared to alfalfa as check, the highest amount of gas production during feed incubation was also related to corn forage. As time increased from 2 to 96 hours after incubation, the amount of gas production for corn and alfalfa increased by 953 and 463%, respectively. In the second experiment, the highest fresh fodder yield of Dehghan cultivar was observed on the planting date of February 27, 2022, by 97.5 t h-1. The highest dry fodder yield was also obtained on the planting date of April 17, 2022 by 19.7 t h-1. The highest cob index was observed on the planting date of October 12, 2021 at a rate of 25.5%. Overall, the results showed that it is possible to cultivate corn in greenhouses at least three times a year (in August, September and April) under similar situations. Total annual yield of fresh and dry fodder for Dehghan cultivar was 249.2 and 52.71 t h-1 in the greenhouse, respectively. |