Response of chickpea to nitrogen and phosphorus fertilization
A field study conducted in 1996 at four locations on soils with relatively low levels of available N and/or to investigate the N and P fertility requirements of desi- and kabuli-type chickpea. The treatments included four levels of “starter N” (46-O-O at 0, 15, 30, and 45 kg N ha-l) and 3 levels of seed-placed P205 (11-54-o at 0,20, and 40 kg P205 ha-l). Regular monitoring of the plots indicated that although growth stages during active plant growth (i.e., days to flowering, pod formation, etc.) were largely unaffected by fertilizer application, seed maturity was, in some instances, extended as a consequence of fertilizer application. Estimates of symbiotic N2 fixation suggest that increasing increments of fertilizer N resulted in concomitant reductions in symbiotic N2 fixation by kabuli-type chickpea whereas symbiotic NZ fixation by desi-type chickpea was less sensitive to inorganic N. Application of “starter N” and seed-placed P205 did not confer a predictable seed yield advantage to either desi- or kabuli-type chickpea. Because results of the 1996 field season indicated few, if any, yield responses to seed-placed N and P, the field design was modified in 1997 to accommodate side-band applications of PI05 fertilizer. As was observed in 1996, application of starter N reduced NZ fixation and did not result in a significant seed yield advantage. Moreover, in 1997, application of P205 did not confer a consistent seed yield advantage at all sites. Similarly, the influence of P205 placement on seed yield was not consistent.
Soils and Crops Workshop