Evaluation the characteristics of additive and replacement series of garlic (Allium sativum L.) and pea (Pisum sativum L.) intercropping in Gonbad Kavoos and Sari regions

Backgrounds and Nowadays, intercropping is highlighted as a solution to optimize usage of inputs, to decline pesticides and to produce safe food in agriculture. The previous studies represent relative advantages of multiple cropping versus sole cropping. Since, garlic and pea are well-adapted plants to northern Iran climatic conditions and there were no comprehensive studies about their intercropping, the present study was aimed to evaluate and determine the best intercropping treatment between garlic and pea in terms of yield.
The research was conducted at research farm of Gonbad Kavoos University and Sari during 2013-2014. The experiment was arranged based on randomized complete block design with three replications. Treatments were nine levels including sole cropping of garlic and pea and replacement series of 25:75, 50:50 and 75%:25% pea: garlic and additive series of 25, 50, 75 and 100% pea 흍% garlic.
The biological yield of garlic in Gonbad region (2357.21 g/m2) was 10 percent lower than Sari region. Means sulfur percentage in garlic bulb was recorded 0.81 and 0.94 for Gonbad Kavoos and Sari, respectively. The maximum bulb yield (1193.42 g/m2) was belonged to sole cropping of garlic in Sari conditions. Seed yield of pea was 399.3 and 736.17 kg/ha in Gonbad Kavoos and Sari, respectively. Results indicated that the maximum seed yield of pea was recorded in sole cropping and followed by additive series of 100% garlic 100% pea by 53.3 g/m2. In Sari region, the seed nitrogen and phosphorous content in was 4.85 and 0.29 %, respectively and was 3 and 11.5 % more than Gonbad. The maximum seed potassium (1.53%) was related to additive series of 25% pea 100% garlic in Sari conditions. The highest land equivalent ratio (1.76), relative crowding coefficient (7.4), aggressivity (0.79) and relative value total (1.53) was recorded when additive series of 75, 25, 100 and 75 % of pea 100% garlic intercropped in Sari climatic conditions, respectively.
was related to additive series of 25% pea 100% garlic in Sari conditions. The highest land equivalent ratio (1.76), relative crowding coefficient (7.4), aggressivity (0.79) and relative value total (1.53) was recorded when additive series of 75, 25, 100 and 75 % of pea 100% garlic intercropped in Sari climatic conditions, respectively.
Overall, results of different additive and replacement series of intercropping showed that the additive series intercropping of 75 and 100 % pea 100% garlic resulted the maximum quantitative and qualitative yield in both studied regions