TITLE:
No-Till Systems: Why Not for Bush Beans (Phaseolus vulgaris cv. HM 21-7) Intercropped with the East African Highland Banana?
AUTHORS:
Tony M. Muliele
KEYWORDS:
Manual Tillage, Beans, Yield, Intercropping Systems, Highland Banana
JOURNAL NAME:
Open Access Library Journal,
Vol.10 No.7,
July
21,
2023
ABSTRACT: Manual tillage is usually practiced in small-scale banana-beans intercropping systems in the Eastern Democratic Republic of Congo (DR Congo). This study tested the hypothesis that manual tillage in banana-beans intercropping systems may increase bean yield. The study was carried out at INERA Mulungu Research Station in the Eastern DR Congo, from February 2014 to May 2017. Four treatments with repetitions were applied under a completed randomized blocs design. Tillage with hand hoe + beans + mulch exportation (T0 or common local system); no Tillage + beans + self-mulch (T1), Tillage with hand hoe + beans + self-mulch (T2), and no Tillage + beans + mulch exportation (T3). Bean yield and banana leaf area index (LAI) were assessed during three bean growing seasons. The relationship between bean yield and banana LAI was computed using a boundary line analysis approach. Bean yield ranged between 187 and 394 kg·ha-1 with higher values during the first two seasons. Treatments did not significantly affect bean yield, but the overall means of bean yield decreased in the order of T0 (324.8 kg·ha-1) > T1 (294.4 kg·ha-1) > T2 (291.2 kg·ha-1) > T3 (273.2 kg·ha-1). Banana LAI ranged from 0.96 to 1.56, and treatments were not significantly different. The relationship between banana LAI, and bean yield shows a cut-off at LAI equals to 1.18, above it bean yield decreases sharply. The specific effects of tillage (T0 versus T2) and soil cover (T1 versus T3) show only a slight increase in bean yield, 34 kg·ha-1 and 21 kg·ha-1 respectively. Manual tillage did not significantly improve bean yield, farmers in the study area are encouraged to use no-till with self-mulch in banana-beans intercropping systems. However, to improve beans’ performance, banana LAI should be below 1.18.