Nitrogen uptake and transfer in broad bean and garlic strip intercropping systems

Utilization and transfer of nitrogen （N）in a strip intercropping system of garlic （Allium safivum L.） and broad bean （Vicia faba L.） have been investigated rarely. The objectives of this study were to quantify N uptake and utilization by intercropped broad bean and garlic and determine the magnitude of N transfer from broad bean to garlic. Field and pot trials were carried out in the Erhai Lake Basin in China using ^15N tracer applied to the soil or injected into broad bean plants. Strip intercropping of garlic and broad bean increased N absorption （47.2%） compared with sole crop broad bean （31.9%） or sole crop garlic （40.7%） and reduced soil residual N. Nearly 15% of 15N injected into petioles of broad bean intercropped with garlic was recovered in garlic at harvest, suggesting that N could be transferred from broad bean to strip intercropped garlic. The findings provide a basis for evaluating legumes＇ role in optimizing N fertilization when intercropped with non-legumes.