Interspecific Facilitation of Nutrient Uptake and Productivity Performance of Finger Millet-Green Gram Intercropping System under Varying Moisture Availability

Finger mi llet (FM/ Eleusine coracana L. Gaertn.) and green gram (GG/ Vigna radiata L. Wilczek) are suitable crops to be cultivated  under moisture-limited conditions. This experiment investigated the interspecific facilitation of nitrogen  (N) and phosphorus (P) uptake and productivity performance of FM-GG intercropping system under moisture-s tressed conditions. In a pot experiment, two crop species were cultivated as mono-cropping and intercropping under two moisture levels (well-watered and moisture-stressed).  Soil moisture in well-watered condition was maintained at 80% of field capacity, whereas moisture-stress was  imposed with 40%. Plant dry weight, panicle/ grain yield, uptake of N and P, and use efficiency of those nutrients i n biomass production were measured. Moisture-stress significantly (P<0.05) decreased the panicle/grain dry weight of  FM and GG. Though intercropping had no yield advantage for FM or GG either in well-watered or moisture-stressed c onditions, intercropped FM under drought stress and well-watered conditions had respectively 42% and 53% greater grai n N accumulation than those of its monocultures. FM grown  with GG acquired more (P<0.05) N than those cultivated in mono-cropping system indicating the interspecif ic facilitation of N uptake by FM in intercropping. Grain N accumulation of FM was also enhanced in intercroppin g system. There were no P benefits from the intercropping. The study indicates that interspecific facilitation  of nutrient uptake in FM-GG intercropping happens only for N, resulting in grain N fortification of FM. Incorporati on of legumes, particularly green gram, into FM cultivation in drought-prone areas could be a potential strategy for g rain N enrichment of FM.