Effect of varieties and planting dates of bread wheat-lupine intercropping system under additive design in Northwest Ethiopia

Abstract Food production on ever-dwindling agricultural land is a severe problem in Ethiopia, necessitating the adoption of more efficient and sustainable land-use strategies to feed the country's growing population. The benefits of intercropping are known to be limited by a variety of factors such as companion crop sowing date and variety. The present study was therefore initiated to evaluate the effect of varieties and planting dates of lupines in bread wheat-lupine under an additive design intercropping system in Northwest Ethiopia. Field experiments were conducted for two years in Adet and Debre Tabor experimental sites. The treatments consisted of four planting dates of lupines and two varieties of lupine. Moreover, the sole crop of bread wheat (Triticum aestivume L.), local lupine (Lupinus albus L.) and sweet lupine (Lupinus angustiflolius L.) were also included. The experiments were laid out in factorial randomized complete block design (RCBD) with three replications. The results showed that at the Adet experimental site, the highest land equivalent ratio (LER) was recorded in the simultaneous planting of sweet lupine and bread wheat (1.3), followed by the planting of sweet lupine two weeks after bread wheat (1.23). While at Debre Tabor experimental site, the highest LER was recorded in planting sweet lupine two weeks after bread wheat (1.67). A greater area time equivalent ratio (ATER) was reported in the simultaneous planting of sweet lupine and bread wheat (1.29), followed by the planting of sweet lupine after bread wheat (1.22) at the Adet experimental site. A greater ATER was also recorded in the planting of sweet lupine after bread wheat (1.53) had the highest ATER in Debre Tabor, followed by simultaneous planting of sweet lupine after bread wheat (1.39) intercropping. This revealed that sole cropping would necessitate 29 and 53% more area, respectively, to attain the same yield as intercropping. In Adet, the simultaneous planting of sweet lupine and bread wheat intercropping, while in Debre Tabor, planting of sweet lupine two weeks after bread wheat boosted productivity, and production efficiency and is a viable option for increasing household food security.