Evaluation of Yield and Advantages of Forage Legumes with Cereals Intercropping as Second Crop in Paddy Fields

One of the key strategies in sustainable agriculture is to restore diversification into agricultural ecosystems and its effective management. The results of various studies have shown that the ecological advantage of intercropping is due to the efficient use of environmental resources. The purpose of mixed cultivation experiments, especially forage plants, is to increase the yield of forage in quantitative and qualitative terms, maintain the ecological balance and stabilize the system.

In order to compare the forage yield and determine the best planting ratio in mixed cropping of Triticale, Barley, Crimson clover (Trifolium incarnatum L.), and Vicia sativa, an experiment was conducted based on the complete randomized block design with sixteen treatments and three replications in paddy fields of Rice Research Institute of Iran (Rasht) during 2012-2014 for two years. Experimental treatments included pure planting of Triticale, Crimson clover, Vicia sativa, and Barley, planting mixtures of Triticale and Crimson clover with ratios of 70:30, 50:50 and 30:70, planting mixtures of Triticale and Vicia sativa with ratios of 70:30, 50:50 and 30:70, planting mixtures of Barley and Crimson clover with ratios of 70:30, 50:50 and 30:70 as well as planting mixtures of Barley and Vicia sativa with ratios of 70:30, 50:50 and 30:70. The studied traits included plant height, number of stems, number of tillers, number of plants per m2, fresh forage yield, dry forage yield as well as land equivalent ratio (LER) values for fresh and dry forages. The obtained data were analyzed by SAS software and mean comparisons were performed using LSD test.

The results of analysis of the variance showed significant differences between the experimental treatments in most traits. Mean comparison showed that planting ratio of 30% Vicia sativa + 70% Triticale had maximum fresh and dry forage yields with averages of 48844 and 15269 kg. ha-1, respectively. Most treatments had LER of greater than one. Planting ratio of 70% Triticale and 30% Vicia sativa showed LER values of 1.31 and 1.54 for fresh and dry forage yields. The treatment is recommended for planting in paddy fields of Guilan area due to its relative advantage with respect to other planting ratios.

Considering that the main objectives of crop forage production in rice paddy fields are the optimum use of paddy fields, sustainability of rice production, production of forage for livestock, and increasing farmers' incomes, the cultivation of all treatments tested as pure and mixed crops in rotation with rice has no problem with regard to the interference of harvesting of the forages with the time of cultivating the seedling rice.