Productivity and economic viability of a palmarosa–pigeonpea intercropping system in the subtropical climate of north India

The poor viability of the perennial aromatic grass, palmarosa (Cymbopogon martinii Stapf. var. motia), in the first year of planting, restricts its popularity among farmers in India. Two pigeonpea cultivars, Bahar (late maturing), and UPAS–120 (early maturing) were intercropped at different row spacings with palmarosa at a row spacing of 60 cm, in the subtropical climate of Lucknow, north India in 1988/89 and 1989/90. Intercropping with the late maturing cv. Bahar at 300 cm row spacing produced 1·26 t/ha grain (2-year mean) without affecting the growth and yield of the palmarosa. Intercropping improved land-use efficiency by 47%, relative net return by 58% and net economic return by Rs. 12500/ha over a sole palmarosa crop. The grain, stalk and total dry matter yield per plant of pigeonpea was considerably improved when grown at the wider row spacing in the intercropped system than when grown as a sole crop. This indicates that the competition between pigeonpea plants was not reduced when palmarosa was present. Palmarosa tiller production and herb and oil yield were significantly reduced when the distance between rows of pigeonpea was narrowed, demonstrating both the greater susceptibility of palmarosa to lack of light, and also that in palmarosa–pigeonpea intercropping systems, competition exists mainly for light rather than for nutrients and moisture, possibly because the two crop components acquire their nutrients and moisture from different soil layers.Intercropping with the high yielding, late maturing pigeonpea cultivar, Bahar, at 300 cm row distance is recommended to make palmarosa cultivation economically viable in the first year of planting. The selection of high yielding, late maturing pigeonpea cultivars with an upright growth habit is suggested as a further way of improving the economic benefits of a palmarosa–pigeonpea intercropping system.