Evaluation of mustard (Brassica compestris Var. Toria) and legume intercropping under 1:1 and 2:1 row-replacement series systems

Field experiments were conducted at Agricultural Experimental Farm, Giridih, Bihar during the winter seasons of 1992-93 and 1993-94 to compare 1:1 and 2:1 row-replacement series intercropping of mustard (Brassica campestris Var. Toria) with pea (Pisum sativum), with lentil (Lens culinaris) and with gram (Cicer areitinum L.). Intercropping systems were assessed on the basis of new indices termed 'actual yield loss' (AYL) and 'intercropping advantage' (IA), as well as several existing intercropping indices such as LER, RCC and aggressivity. Intercropping reduced the yield of component crops, compared with respective pure stands. Mustard + pea in 1:1 row-replacement series gave the highest mustard yield equivalent value(1.00 t/ha). When the actual sown proportion was considered, mustard+lentil (1:1) resulted in maximum AYL (+0.438) and IA (+2.889) values. We conclude that AYL and IA are more appropriate, particularly when per plant yield is considered.