A permanent plot experiment in the wheat-rice pattern initiated in November 1997 at Wheat Research Centre (WRC), Dinajpur, Bangladesh (250 38' N, 880 41' E, 38.2 m above sea level) on a sandy loam on a Old Himalayan piedmont plain. At the beginning of the experiment, the soil was low in available N, medium in available P, low in exchangeable K, medium in available S and medium in Zn. The soil reaction was acidic. The experiment consisted of 9 treatments laid out in a randomized complete block design with 4 replications. The treatments for wheat were: control (T1), 100% NPKSZn (T2), 75% NPKSZn (T3), 75% NPKSZn+FYM (T4), 75% NPKSZn+FYM (T5), 75% NPKSZn (T6), 75% NPKSZn+PM (T7), 75% NPKSZn+PM (T8) and 75% NPKSZn (T9). In case of rice, the treatments were control (T1), 100% NPKSZn (T2), 75% NPKSZn (T3), 75% NPKSZn (T4), 75% NPKSZn+FYM (T5), 75% NPKSZn+FYM (T6), 75% NPKSZn (T7), 75% NPKSZn+PM (T8) and 75% NPKSZn+PM (T9). For rice, FYM (Farm yard manure) and PM (Poultry manure) were excluded from the treatment T4 and T7 to observe residual effects in rice of FYM and PM, respectively. FYM and PM were included to T6 and T9, respectively to see the direct effects of FYM and PM in rice. Wheat and rice received FYM and PM in the treatments T5 and T8, respectively to evaluate the effect of double application of organic manures per year for each of those crops. One hundred percent rates of recommended chemical fertilizers for both wheat and rice were 26kg P, 33kg K, 20kg S and 4 kg Zn ha-1. However, the 100% recommended rate of nitrogen was 100 and 70kg ha-1 for wheat and rice, respectively. Organic manures, both PM and FYM were incorporated @ the rate of 10t ha-1 to soil 4-5 and 15 days before seeding wheat and transplanted monsoon rice, respectively. The dry matter FYM was added at 69.52, 128.12 and 58.60 ton ha -1 FYM to wheat, both crops and rice, respectively. The dry matter PM was added as 85.69, 162.89 and 77.20 ton ha-1 PM to wheat, both crops and as rice, respectively. Chemicals fertilizers were applied using recommended times and methods for the crops. Wheat seed @ 120 kg ha-1 was sown at the optimum time (last week of November) every year and the crop was harvested at maturity (Normally 112 days after sowing). Thirty to thirty- seven-day old seedlings of monsoon rice were transplanted on the last week of July every year and the crop was harvested at maturity in the 1st week of November. Weeding was done once for wheat after 1st irrigation and rice 25 days after transplanting. Three irrigations were applied to wheat at 17, 50 and 70 days after sowing (DAS). The rice was grown with natural monsoon rain, but one irrigation was given the 1st week of October (if necessary). Plant protection measures viz. insecticide and fungicide sprays, were not necessary since the wheat crop remained free from insect and pathogen damage. The monsoon rice requited, Marshal, an insecticide @ 1.0 litre ha-1 which was applied twice to control stem borer. The surface soil (0-15cm) was sampled at the beginning from the experimental site and from individual plots after completing 3 and 9 crop cycles and chemically analyzed to determine %total N, available P, exchangeable K, available S, %organic matter and pH. Data were statistically analyzed with MSTAT following the F-test and mean comparisons were made by DMRT at the 0.05% level.