Phosphorus management in rice (Oryza sativa)–autumn sugarcane (Saccharum officinarum) cropping sequence

A field experiment was conducted during 2004–05 and 2005–06 on deep black soil of Navsari, Gujarat to study the direct and residual effect of pressmud biocompost and direct effect of phosphorus in rice (Oryza sativa L.) sugarcane (Saccharum officinarum L.) cropping system. Application of pressmud biocompost @ 40 t/ha to rice recorded significantly higher grain yield (5.41 and 5.24 t/ha), total P uptake (9.72 and 9.79 kg/ha) by rice and available P status of soil (15.41 and 9.74 kg/ha) after harvest of rice than control (no phosphorus) during both the years and remained at par with application of pressmud biocompost @ 20 t/ha. Similarly application of pressmud biocompost @ 40 t/ha to preceding rice recorded significantly higher millable cane weight (1.14 and 1.26 kg), millable cane yield (108.6 and 107.8 t/ha), intercrop yield (0.858 and 1.056 t/ha), sugarcane equivalent yield (114.55 and 115.35 t/ha), available P status of soil (14.17 and 9.53 kg/ha) after harvest of sugarcane and net realization from rice-sugarcane cropping system (1,23,800 and 1,49,300/ha) over other treatments during both the years. Application of recommended dose of P/ha (54.59 kg/ha) to sugarcane raised without intercrop of greengram [Vigna radiata (L.) Wilczek] recorded significantly higher millable cane yield (115.4 and 116.8 t/ha) than rest of the treatments. While, sugarcane equivalent yield (119.49 and 123.30 t/ha), available P status of soil (13.86 and 10.51 kg/ha) after harvest of sugarcane as well as net realization (1,32,500 and 1,64,300/ha) were obtained higher under application of recommended dose of P/ha (54.59 kg/ha) to sugarcane raised with intercrop of greengram.