Avanços na ciência e tecnologia agrícola

Abstrato

Yield and Agronomic Performance of Selected Bean Varieties against Major Bean Diseases in Rwanda

Floride Mukamuhirwa, J P Bizimana and L Kankundiye

Bean is one of the most important legume crops in the world. Root rots are widely distributed around the world and are economically important diseases in common beans. Other fungal diseases such as angular leaf spot, anthracnose, ascoshyta leaf spot, rust; viral diseases such as BCMV and BCMNV may also attack and reduce bean yield. After screening bean genotypes (with different background) for root rot resistance, 25 selected genotypes were used to evaluate their resistance level for major bean diseases such as angular leaf spot, anthracnose, ascochyta, rust, bean common mosaic virus, bean common mosaic necrotic virus and to assess their yield. The experiment was carried out using a Randomized Complete Block Design (RCBD) with three replications. The study results have shown that all genotypes were tolerant to anthracnose, ascochyta leaf spot and rust; 9 genotypes (Gasirida, MAC42 × COLTA, MBC71, Mwirasi, RED RANDISPIONEER, RWR 2245 × G12727AB136, RWV 3006 × G122164 AB136, MEXICO 54 × MEXICO 235) were the most tolerant to angular leaf spot; 23 genotypes were tolerant to BCMNV and 9 genotypes (MAC44, RWR 1668, RWR 2154, CIM RM00321, MAC 49, MBC 71, RWR 3194, SC B790, RWR 3228) tolerant to BCMV. Except the number of pods per plant, the effect of genotype on yield components (plants harvested, seed per pod, 100 seed weight and yield) was highly significant among genotypes. 14 genotypes presented a good yield (more than 2t/ha). Climbing genotype MAC 44 was the high yielding genotype followed by Gasirida with a yield of 5.3 tones and 5.0 tones respectively while genotypes namely RWR3228, CAL96, CIMRM00321 and RWR 3194 were the bush bean genotypes with a high yield of 4.8 tones, 3.6 tones, 3.3 tones and 3 tons respectively.