Nutrient Management Strategies for Guangdong

The past 2 years of study have revealed details on the growth of the banana rooting system and has shed new light on improved fertilizer placement methods. This field experiment was conducted to screen four methods of fertilizer placement, including broadcasting during the entire growth period (BrE), broadcasting at early growth stages and ditch banding at later stages (BrBd), fertigation at early stages and broadcasting at later stages (FgBr), and fertigation at early stages and ditch banding at later stages (FgBd). All methods used the same fertilizer rates of 557-179-632 kg N-P₂O₅-K₂O/ha split nine times during the growth period.

The methods of fertilizer placement produced big differences in yield as well as incidence of blight, a destructive disease. The broadcast-based BrE and BrBd treatments improved plant height and thickness of the pseudo stem at the vegetative and flower development stages, and advanced flower emergence by 40 to 100% compared to the fertigation-based FgBr and FgBd treatments. Broadcasting fertilizers at early growth stages also led to slightly better finger weights and girths. However, at maturity the FgBd treatment produced marginally higher fruit yields, which were 867 kg/ha (1.7%), 1,838 kg/ha (3.7%), or 1,965 kg/ha (4%) higher than the BrE, FgBr, or BrBd treatment, respectively. The FgBd treatment also improved contents of vitamin C and soluble sugar in the fruit. Regardless, the two broadcast treatments generated better net incomes, BrE in particular, than the two fertilizer ditch banding treatments due to higher labor inputs. Cases existed where fertilizer banding did damage roots during the ditch preparation and led to increased banana infection by blight. Banana plants receiving broadcast fertilizers were free of blight while infection rates in nearby farmer fields were measured at 17%.

Based on results of this experiment, and research from Ecuador, fertilizer broadcasting with sufficient split times is desirable for banana production to acquire both high yield and economic returns. Guangdong-NMS02