Effects of Chicken Manure and Chemical Fertilizer Management on Yield of Cassava Grown on Map Bon, Coarse-Loamy Variant Soil

Abstract

The objective of this research was to evaluate the effects of chicken manure and chemical fertilizer management on cassava growth and yield. The experiment was carried out in randomized complete block design with three replications from June 2009 to June 2010, using HB 80 cassava cultivar grown on Map Bon, a coarse-loamy variant, at Khao Hin Son Research Station, Phanom Sarakham District, Chachoengsao Province, Thailand. There were 10 treatments: T1, no fertilizer application (control); T2, application of 15N–15P2O5–15K2O chemical fertilizer at the rate of 312.5 kg ha−1 at 1 month after planting; T3, application 15N–5P2O5–20K2O chemical fertilizer at the rate of 312.5 kg ha−1 at 1 month after planting; T4, application of chicken manure (CM) at the rate of 6.25 t ha−1 before planting; T5, application of CM at the rate of 3.125 t ha−1 before planting + 15N–15P2O5–15K2O chemical fertilizer at the rate of 156.25 kg ha−1 at 1 month after planting; T6, application of CM at the rate of 3.125 t ha−1 before planting + 15N–5P2O5–20K2O chemical fertilizer at the rate of 156.25 kg ha−1 at 1 month after planting; T7, application of CM at the rate of 6.25 t ha−1 before planting + 15N–15P2O5–15K2O chemical fertilizer at the rate of 156.25 kg ha−1 at 1 month after planting; T8, application of CM at the rate of 6.25 t ha−1 before planting + 15N–5P2O5–20K2O chemical fertilizer at the rate of 156.25 kg ha−1 at 1 month after planting; T9, application of 46N–0P2O5–0K2O chemical fertilizer at the rate of 156.25 kg ha−1 at 1 month after planting + 15N–15P2O5–15K2O chemical fertilizer at the rate of 156.25 kg ha−1 at 2 month after planting; T10, application of 46N–0P2O5–0K2O chemical fertilizer at the rate of 312.5 kg ha−1 at 1 month after planting + 15N–5P2O5–20K2O chemical fertilizer at the rate of 156.25 kg ha−1 at 2 month after planting. It was found that the treatments with various rates of CM or chemical fertilizer that contained N, P, and K were not different in fresh root yield but treatments with CM and chemical fertilizer tended to give greater fresh root yield or have greater effect on it, and plant height was not affected. The treatments with 3.125 kg ha−1 of CM and 156.25 kg ha−1 of 15–15–15 gave significantly greater fresh root yield of cassava (52%). All fertilization treatments were not different in fresh stem weight but treatments with 3.125 kg ha−1 of CM and 156.25 kg ha−1 of 15–15–15 tended to give significantly greater fresh stem weight of cassava (62%). All fertilization treatments were not different in root starch percentage and root number as compared with control.