Compensating nutrient requirement in pearl millet (Pennisetum glaucum)–wheat (Triticum aestivum) cropping system through manures and biofertilizers in semi-arid regions of Haryana

A field experiment was conducted for 4 years, ie from rainy (kharif) season 2004 to winter season 2007–08 at Hisar to study compensating requirement in pearl millet [Pennisetum glaucum (L.) R. Br. Emend. Stuntz]–wheat [Triticum aestivum (L.) emend. Fiori & Paol.] using manures and biofertilizer. The recommended dose of 40 kg N + 20 kg P2O5/ ha to pearl millet and 60 kg N + 30 kg P2O5/ha to wheat + 20 kg K2O/ha (T1) and 50% of the recommended dose of nitrogen in both the crops + 5.0 tonnes farmyard manure before pearl millet sowing + seed inoculation with Azospirillum in pearl millet and Azotobacter in wheat + phosphate-solubilizing bacteria (PSB) (T4) resulted 54.1 and 46.6% higher grain yield yield than the control (no application of any fertilizer). In wheat, the grain yield under treatment T1 being at par with 100% of the recommended dose of N and P in both the crops (T2), recommended N in both the crops (T3), T4 (3 047 kg/ha) and T5, 50% of the RDN in both the crops + 2.5 tonnes farmyard manure before pearl millet sowing + seed inoculation with Azospirillum in pearl millet/Azotobacter in wheat + PSB (3 102 kg/ha) was statistically better than T6, 15.0 tonnes farmyard manure before pearl millet sowing + seed inoculation with Azospirillum in pearl millet and Azotobacter in wheat + PSB (2 664 kg/ha), T7, 7.5 tonnes vermicompost before pearl millet sowing + seed inoculation with Azospirillum in pearl millet and/Azotobacter in wheat + PSB (2 735 kg/ha) and control (2 154 kg/ha) treatments. Maximum pearl millet equivalent yield was in the T1 (11 991 kg/ha) which was followed by T2 (1 1684 kg/ha), T5 (11 096 kg/ha) and T4 (10 973 kg/ha) treatments. On mean basis, protein content was highest in T4 (11.14%), followed by T3 (11.09%) and T5 (11.06%). In wheat crop maximum content was in T7 treatment (11.13%), followed by T6 (11.00%) and T5 (10.99%) and minimum value of 9.99% was recorded in control. The values of pH and electrical conductivity were almost similar in T1, T2 and T3 treatments compared with the control and these values decreased in T4 to T7 treatments. In general, organic carbon content was static where only chemical fertilizers were used but substantial increase was observed where pure organic and biofertilizers were used. Nitrogen and phosphorus balance was higher in organic manure and biofertilizer treatments as compared to inorganic fertilizer treatments. However, potash content decreased compared to initial status in the soil after 4 years of crop sequence of pearl millet–wheat. Treatment T1 gave 54.1 and 110.6% higher gross and net returns over the control (T8). B:C ratio (2.29), System productivity (32.9 kg/ha/ day) and profitability(Rs 155.3 ha/day) were quite higher in T1 treatment than the control (1.70, 21.3 and 73.7, respectively).