ABSTRACT
There is a considerable deficit in the annual production of cassava in Cameroon of about 31 million tons, and this has been mainly due to constraints related to pest attacks and most especially diseases like the African Cassava Mosaic Disease (ACMD). This study was therefore undertaken on three sites in the locality of Bityili (South Region of Cameroon), to determine amongst improved and local cassava cultivars those that provide resistance to the development of the ACMD. The severity and incidence of this disease was evaluated and its impact on cassava yield. In each site, cassava was grown in a randomized complete block design. The local cultivars (Ekobele and Ngon kribi) showed higher severity (76-100%) and incidence of ACMD compared to the improved cultivars (TMS 92/0326 and TMS 96/1414) of 0-25% and 0-10%, respectively. Strong inverse correlations were observed between ACMD severity and yield performance, measured in terms of number of tubers/plant and weight of fresh tubers. The improved cultivars, TMS 92/0326 and TMS 96/1414, could, therefore, be recommended for large-scale planting in a bid to promote cassava production in the South Region of Cameroon.
ABSTRACT
Mineral fertilizer is an environmental hazard and economic discouraging factor for rice farmers in Cameroon. The objective was to assess the effect of groundnut stover as a substitute to mineral fertilizer on agronomic performance of rainfed upland rice in bimodal HFZ. The experiment was carried out during short raining season (August – December 2015). Two doses of groundnut stover: 1.5 t/ha ± mineral fertilizers and 2.4 t/ha ± mineral fertilizers were used, design in a RCBD (randomized complete block designed) with four replications involving NERICA 8 progeny. Thirteen agronomic traits were collected, analyzed and Pearson’s correlation test was performed at 1% and 5% level of probability. There was an overall increase in rice paddy grain yield in the different treatments except in treatment 1.5 t/ha of groundnut Stover (3.5 t/ha) with the highest grain yield of 5.75 t/ha (SR1+ and SR2). Treatments 1.5 t/ha of groundnut Stover + urea+ NPK; 1.5 t/ha of groundnut Stover; 2.4 t/ha of groundnut Stover + urea+ NPK had the lowest number of tillers/plant. Panicle length (PL) correlates with the following traits: NSR (r = 0.762**); 1000SW (r = 0.463*); FG (r = 0.573**); NGP (r = 0.601**) and GY (r = 0.649**), similarly NSR correlated with GY (r = 0.649**). Panicle length (PL) and secondary ramifications (NSR) are NERICA traits important for an increase in grain yield under incorporated groundnut Stover in humid forest ecology.
ABSTRACT
Aims: Resistant starch (RS), kinetics of starch digestion, predicted glycemic index (pGI) and nutritional composition were determined in two improved rice varieties from Cameroun. Place and Duration of Study: Department of Bioresource Engineering, McGill University, Canada between December 2012 and March 2013. Methodology: Non-parboiled and parboiled samples of TOX 3145 and NERICA-3 varieties were involved in this study. An in vitro enzymatic starch digestion method was applied to measure starch digestibility parameters. Standardized methods were adopted for proximate and mineral contents evaluation. Results: The parboiled samples had significantly higher (P<0.05) resistant starch (8.35 - 11.07%) than the non-parboiled samples (3.81 - 4.84%). The values for pGI among samples ranged from 57.57 to 67.78%. Significantly higher values for protein, phosphorus and potassium were found among the parboiled samples (P<0.05). Nutritional composition was positively related to RS while pGI had inverse relationship with protein, ash, fat, phosphorus, potassium and RS. Conclusion: Starch digestibility of these rice varieties was associated to their nutritional composition.