Intercropping ginger and turmeric with poplar (Populus deltoides ‘G-3’ Marsh.)

Performance of two rhizomatous crops i.e. ginger (Zingiber officinale Rosc.) and turmeric (Curcuma longa L.) was investigated under rainfed conditions in pure stands and as intercrops with 5-year-old poplars planted at three spacings viz., 5×5 m, 5×4 m and 5×3 m. The average illumination below the canopies was 53, 46 and 38% of incident radiation, respectively. Both crops performed better as intercrops than as pure stands. Survival was inversely correlated to light intensity. Plant height, tillers per plant and leaves per plant in ginger and leaf length and leaf breadth besides plant height in turmeric were significantly enhanced when intercropped. The rhizome length, rhizome breadth, yield per plant and yield per ha in ginger exceeded under poplars but showed a drastic reduction under the closest poplar spacing. In turmeric, the trend for the first two characters was the same, whereas yield per plant as well as yeild per ha were slightly greater in the open than under 5×3 m spacing. Dry matter content varied significantly with spacing. For quality parameters, only oil content in ginger and oleoresin in turmeric showed significant differences. The cultivation of turmeric proved more remunerative than ginger.Among the poplar spacings, 5×4 m for ginger and 5×5 m for turmeric were delineated as the best spacings.