Humid Forest Zone Of Cameroon Research Articles

Agronomic performance of maize hybrids under Aspergillus flavus inoculation in Cameroon

Maize (Zea mays L.) is a major staple crop in most of the sub-Sahara Africa (SSA) region, constrained by a multitude of plant diseases, with the ear and kernel rots being the most widespread and difficult to manage on maize. The objective of this study was to access the agronomic performance of F1 maize hybrids exposed to Aspergillus flavus, under different agro-ecological conditions, in Cameroon. A total of 120 genotypes of maize, including four commercial hybrids, were evaluated under A. flavus infection at two sites; namely Bangangte in the Western Highlands and Mbalmayo, in the Bimodal Humid Forest Zone of Cameroon. The study was conducted during 2020 - 2021 cropping seasons. Results revealed that at Bangangte site, six (89343X88094, 88099X88094, 90204XExp 124, 89246X87036, TZI-5-1171XExp 124 and 90219X1368) out of the top 20 high yielding hybrids, had significantly high (p<0.001 tolerance (0% severity) to Aspergillus ear rot infection. At Mbalmayo site, eight (8923X88094, TZI-5-1171XExp124, 89343X88094, 90219X87036, 89243X87036, 87014X88094, TZSTR1150X87036 and 89248X88094) out of the top 20 high yielding hybrids also showed significant high (P<0.001) tolerance (0% severity) to Aspergillus ear rot infection. The interaction between hybrids and location was significant (P<0.05) for all measured traits, except ear height, grain texture, ear insect damage and husk cover (P>0.05). The pooled broad sense heritability of hybrids in the two locations varied from 5% for grain texture to 92% for days to 50% physiological maturity. Grain yield was negatively correlated with Aspergillus ear rot disease incidence and severity. Hence, promising high yielding maize hybrids with appreciable tolerance to Aspergillus ear rot disease could be selected among the tested genotypes.

English

The primary efforts in any wheat breeding program are the targeting of important traits and the detection of genetic diversity among different wheat genotypes in different environments. Hence to identify prominent traits in wheat lines in low altitude conditions of the bimodal humid forest zone of Cameroon, 38 wheat lines were characterized on the base of morphological traits. The field experiment was conducted in low altitudes conditions in 2016-2017. 18 morphological traits were scored on the 38 wheat lines sown following an incomplete alpha-lattice design. The result obtained revealed a high genetic variation among all the studied traits in this area. Correlation and path correlation analysis revealed overall positive influence of the glossiness of grains and grain color on the grain quality character. Factors analysis based on principal component analysis revealed 3 important factors with a cumulative variance of 40.3%. The first important factor F1, explaining 16.7% of the variance was composed of Plant habit (Phb), Tiller number (Tnu), Culm thickness (Cthic), and Spike density (Sde). The second factor (F2) explaining 12.4% of the variance was composed of Leaf angle (Lan), Glume color (Glco), and Spike density (Sde). The third factor (F3) explaining 11.2% of the variance was composed of Grain color (Gco), Grain quality (Gqu) and Glossiness of grain (GlGr). Thus, suggesting suitable characters for wheat breeding programs in this studied area. The determination of contribution of variance and cluster analysis studies allowed observing that the wheat lines SST835, Konstrad F2004- 1, Kenya2, SST843, SST806, Pfau4, Sup152-1 and Nd643-2 highly contributed to the variance in each factor with a high genetic dissimilarity among them. Thus, suggesting they may possess a high genetic polymorphism that could be further explored through molecular techniques for breeding programs. Key words: Genetic traits, wheat line, breeding programs.

Production, consumption and market diversification of grain legumes in the humid forest agroecology of cameroon

Grain legumes are mostly cultivated for food and income security. However, the productivity of most grain legumes remains low, with ensuing impacts on consumption and marketing. This study aims at characterizing major grain legumes with regards to production, consumption, and sales in the humid forest zone of Cameroon. The research targets explicitly agricultural households in which the production, consumption, and marketing decisions are made sequentially. To evaluate the socioeconomic determinants driving these decisions, we employed the Tobit censored regression model. Our results present empirical evidence that households participate in markets after satisfying their food consumption needs. Female-headed households are more involved in the production and marketing of legumes. We thus provide evidence-based policy directives to target women into farming systems by empowering them and increasing their access to improved seeds and farmland. Informal education is also essential as it increases the indigenous knowledge base of farming households in the production, consumption and marketing of legumes.

Production Constraints, Farmers’ Preferred Characteristics of Maize Varieties in the Bimodal Humid Forest Zone of Cameroon and Their Implications for Plant Breeding

Many high-yielding improved maize varieties have been developed in Cameroon, though only a limited number of farmers have adopted them. A participatory rural appraisal consisting of focus group discussions and formal surveys was conducted in 140 households in six villages of the Central Region in the Bimodal Humid Forest Zone of Cameroon. The objective of this study was to identify constraints to maize production and farmers’ preferred maize characteristics which can be used as selection criteria by maize breeders to develop appropriate varieties as preferred by farmers. Results revealed that the most important constraints to maize production in the study area are unavailability and high cost of seeds of improved varieties (53.8%), low soil fertility (50.0%), lack of labor (48.0%), unavailability or high cost of fertilizers (41.2%), difficulty in weeding (38.9%) and post-harvest losses (31.0%). Farmers’ preferred characteristics in maize varieties were large grain size, soft grain texture, large ear size, high prolificacy, early maturity, short plants, resistance to lodging, resistance to diseases and reduced post-harvest losses. Based on these findings, there will be increased adoption of improved maize varieties if maize breeders address the identified constraints and take farmers ‘preferred traits into account while developing new varieties. Some farmers of the study area are interested in growing hybrids. Therefore, high-yielding maize hybrids with the identified traits and which are adapted to low soil fertility should be developed and promoted, hence increasing maize production. Breeders should collaborate with extensionists to ensure that varieties developed are grown with appropriate technical package for good results and high adoption.

The Effects of Hydro Priming Intervals on the Germination and Yield of Kidney Beans (Phaseolus vulgaris L.) in the Humid Forest Zone of Cameroon

The aim of this research was to evaluate the appropriate hydro-priming interval on germination, growth and yield of kidney beans (Phaseolus vulgaris L.).
 The experiment was conducted in a Completely Randomized Block Design, with five treatments, replicated thrice.
 This study was conducted at the agricultural research farm of Pan African Institute for Development – West Africa (PAID-WA), Buea from August to October 2017.
 The Five treatments were: T1 (Unprimed or control), T2 (Hydro-primed for 6 hours), T3 (Hydro-primed for 12 hours), T4 (Hydro-primed for 18 hours), and T5 (Hydro-primed for 24 hours). Data were collected on percentage germination, plant height, stem diameter, number of leaves per plant, number of pods, pod weight and grain yield.
 The result revealed there was a significant increase in days (P < 0.05) in the germination percentage of some primed seeds and unprimed seeds across the treatment. There was not any significant difference (P > 0.05) in plant height, number of leaves, plant girth from T1 to T5. There was a significant difference (P < 0.05) in the number of pots among the primed treatments. Yield of beans also showed a significant difference (P < 0.05) with unprimed and primed plants. Seeds of T2, T3, T4, T5 produced the following yields 11.1 kg/ha, 22.3 kg/ha, 172.3 kg/ha, 277.8 kg/ha more than unprimed seeds (control) respectively.
 This study showed that hydro primed seeds for 6 hours produced the best growth and development aspect as well as the yield, despite the low germination percentage as compared to the unprimed and the other primed seeds.

Short-Term Benefits of Grain Legume Fallow Systems on Soil Fertility and Farmers Livelihood in the Humid Forest Zone of Cameroon

Short-Term Benefits of Grain Legume Fallow Systems on Soil Fertility and Farmers Livelihood in the Humid Forest Zone of Cameroon

Agro-environmental characterization of biochar issued from crop wastes in the humid forest zone of Cameroon

PurposeCrop wastes are underused organic resources due to low heating value and slow decomposition rates. However, conversion to biochar through pyrolysis could offer agronomic and environmental benefits. The study compared the pyrolysis of biochar from crop wastes, assessed their physicochemical properties for the purposeful use to improve soil fertility, crop productivity and their carbon sequestration potential.MethodsBiochar was produced from crop wastes such as cassava residues, corncobs, rice husk, sawdust, coffee husk, and peanut using an Elsa barrel pyrolyser. Standard laboratory procedures were used to analyze pH, CEC, total carbon and nitrogen and exchangeable cations.ResultsThe biochars were high in nutrients containing 4.17–18.15 g kg−1 N, 22.26–42.51 mg kg−1 P, 2.48–4.18 cmol kg−1 K and pH 7.78–10.81 units. It is evident that adding biochar to acidic soil containing 0.79 g kg−1 N, 7.41 mg kg−1 P, 1.42 cmol kg−1 K and pH of 5.68 could increase soil fertility and plant productivity. Carbon dioxide reduction potential ranged from 94.46 to 313.42 CO2 eq kg−1. This implies that the concept and technique of producing biochar could be a valuable way of reducing carbon emissions into the atmosphere thereby mitigating climate change.ConclusionCrop wastes and by-products which constitute a nuisance could be used to produce a very useful by-product, biochar whose quality depends on the substrate from which it is produced. Recycling crop wastes to biochar is strongly recommended to smallholder farmers for use in agriculture to improve fertility and crop productivity due to their high nutrient content and soil fertility attributes.

Phosphorus Speciation by 31P NMR Spectroscopy in Leaf Litters and Crop Residues from Para Rubber, Cocoa, Oil Palm, and Banana Plantations in the Humid Forest Zone of Cameroon

The release of nutrients, including phosphorus from agricultural residues, is an important potential source of nutrients for subsequent crops. To fully understand the contribution of this residue P as a source of plant P for agricultural production, its chemical nature needs to be understood. In this study P species were identified and quantified in leaf litters and crops residues from cocoa farms, oil palm, rubber, and banana plantations by 31P nuclear magnetic resonance (NMR) spectroscopy. Phosphorus in the crop residues was predominantly in the form of inorganic P mainly as orthophosphate and ranged from 45.9 to 89.2%. The highest relative percentage of P as orthophosphate was found in cocoa pod husk (89.2%) and the lowest percentage was found in decaying banana pseudostem (45.9%). Pyrophosphate was detected in trace amounts in all samples (less than 6%) except in fresh palm fronds. However, orthophosphate diester was detected only in fresh palm fronds (11.4%) and phytate was detected only in palm male inflorescence (6.7%). The result implied that cocoa pod husk, palm empty fruit bunch, and palm male inflorescence could be used as organic amendment, based on their high P content and release potential.

Vegetative propagation of Garcinia lucida Vesque (Clusiaceae) using leafy stem cuttings and grafting

Garcinia lucida Vesque (Clusiaceae) is a tree species that is highly valued for its medicinal properties by rural households in the humid forest zone of Cameroon. However, the unsustainable exploitation of the species threatens its long-term regeneration. This study focuses on its vegetative propagation via stem cuttings in non-mist propagators and through grafting. The study tests the effects of three rooting media (sand, sawdust, sand + sawdust (1/1); three leaf sizes (0,25 and 50 cm2); and three types of hormone [indole butyric acid (IBA), indole-3-acetic acid (IAA) and naphthalene acetic acid (NAA)], applied as a single dose. Furthermore, three grafting techniques (cleft, side tongue and whip-and-tongue grafting) were tested. All experiments were designed as completely randomized blocks with three replicates. Results showed that cuttings require a medium that has low water holding capacity and high porosity, and a leaf area of 50 cm2 and NAA treatment; grafting success was affected by the technique used, with top cleft grafting yielding a 100% success rate. From this preliminary study, it is concluded that G. lucida is amenable to vegetative propagation by cuttings and grafting. Key words: tree domestication, leaf area, non-mist propagator, rooting hormone, rooting medium, under-utilised species

Identification of Farmer’s Constraints to Maize Production in the Humid Forest Zone of Cameroon

Identification of Farmer’s Constraints to Maize Production in the Humid Forest Zone of Cameroon

Harvesting Date Influences Cassava (Manihot Esculenta Crantz) Yield and Quality of Based-Products

In order to evaluate cassava roots yield of two varieties at three harvesting dates and assess the effect of harvesting date on physico-chemical composition of roots and quality of gari and baton de manioc, a study was done. Cassava roots of a popular variety (local white) and the improved variety 8034 were harvested in small holder farmers’ fields in the mono-modal humid forest zone and the bimodal humid forest zone of Cameroon. At harvest, the yield was evaluated, the physico-chemical composition of roots evaluated and a sensory test carried out on gari and baton de manioc after processing. Results showed that harvesting date has an effect on the cassava roots yield, for both local white and variety 8034. Cassava yield varied according to agro-ecological zones, with higher yield in the mono-modal humid forest zone than the bimodal humid forest zone. The nutrient content in cassava root varied with the variety and age of roots. There was an increase with the age of roots for K, P and dry matter content for the variety 8034. With the local white variety, there was an increase in total N and dry matter content. In contrary, there was a gradual decrease of percentage Mg, K, Na with the age of cassava roots for the variety 8034.Baton de manioc obtained from variety 8034 at 10-12 months and gari obtained from same variety were scored the highest global quality.

Screening of Maize (Zea mays L.) Genotypes for Adaptation on Contrasted Acid Soils in the Humid Forest Zone of Cameroon

Screening of Maize (Zea mays L.) Genotypes for Adaptation on Contrasted Acid Soils in the Humid Forest Zone of Cameroon

Above Ground Biomass and Carbon Stock in Some Perennial Crop Based Agroforestry Systems in the Humid Forest Zone of Cameroon

Above Ground Biomass and Carbon Stock in Some Perennial Crop Based Agroforestry Systems in the Humid Forest Zone of Cameroon

Soil chemical properties dynamics as affected by land use change in the humid forest zone of Cameroon

The conversion of forests to other forms of land use has profound effects on the distribution and supply of soil nutrients. Understanding the effects of land use on soil is essential for addressing agroecosystem transformation and sustainable land productivity. Although soil carbon stock has been previously examined in the humid forest zone of Cameroon, the dynamic and interactions between other soil chemical properties has been poorly addressed to date. The present study used the quadrat approach to assess the effect of four land use types (secondary forest, fallow, cocoa plantation and mixed cropping) on soil chemical properties. Soil samples were collected at two different depths (0–10, 10–30 cm) in all land use types and analyzed for pH, total carbon, soil organic carbon, total nitrogen, cation exchange capacity (CEC), calcium (Ca), potassium (K), magnesium (Mg) and boron (B). Land use type significantly affected B, Ca, K and pH: in general, these properties were higher in cocoa plantation and mixed cropping than in secondary forest and fallow. All soil properties were significantly greater in the upper than in the lower soil depth. In addition, all soil properties differed significantly among sites and villages within sites. Pearson correlations between soil chemical properties were positive and generally significant in the four land use types, except for some correlations with B, pH and CEC. Despite the fact that some of the fundamental soil chemical properties (carbon, nitrogen, CEC and Mg) did not differ among the four land use types, high density tree-based production systems are recommended for the storage of these elements in the soils.

Abundance of Legume Nodulating Bacteria in Soils of Diverse Land Use Systems in Cameroon

Improving biological nitrogen fixation through legume nodulating bacteria (LNB) inoculation requires knowledge on the abundance and effectiveness of indigenous population in the ferralsols. The Most Probable Number method (MPN) was used to determine the naturally occurring LNB population in 64 representative soils of four sites in the humid forest zone of Cameroon. Nodulation Macroptilium atropurpureum was examined under tubes experiment in four location sites: Bertoua, Ebolowa, Bokito and Yaounde, and within each of the locations, in four land use systems (LUSs) of different levels of disturbance: mixed farm; fallows; cocoa plantation and forest. The LNB population size varied from 0.78 to 5.25 log units of soil depending on the land use. The most disturbed LUSs (farms and fallows) exhibiting the highest number of LNB on average. Undisturbed ones (cocoa plantation and forest) showed the lowest number of LNB. The percentage of the need for inoculation was more frequent in the forests (94%) and plantations (75 %). It is low in the in the fallows (25%) and the farms (44 %). In total 60 % of the soils analysed need inoculation. These results are important for future investigations on alternative inoculant strains for improving legume production in Cameroon.

Effects of Cassava Cultivation on Soil Quality Indicators in the Humid Forest Zone of Cameroon

A study was conducted at Ongot in the humid forest zone (HFZ) of Cameroon to determine the extent to which selected soil quality indicators are affected by cassava cultivation along a chronosequence of 5, 10 and 20 years. Soil samples were collected from cassava farms along this chronosequence and from a nearby forest as reference. The samples were analyzed for soil organic matter (SOM), organic carbon (OC), total nitrogen (TN) and pH. SOM, OC and TN decreased significantly (P<0.05) following years of cassava cultivation. Thus after 20 years of cultivation, SOM and OC contents reduced by 50% compared to the reference (SOM=35.08 g kg-1, OC=20.39 g kg-1). TN decreased from 2.19 g kg-1 in the reference to 1.24 g kg-1 in farms where cassava has been cultivated for 20 years. Soil pH ranged from 5.4 to 5.6 but did not differ (P<0.05) irrespective of years of cassava cultivation. Generally, significant differences in soil quality indicators were not observed between the forest soil and soils from five-year old cassava farms. This could imply that management strategies to improve soil quality in the HFZ of Cameroon are warranted mainly after four years of cassava cultivation.

English

With slash-and-burn agriculture, changes in soil properties occur, which could influence crop production and future soil fertility recommendations. The objectives of this study were to: Identify dynamic soil properties that could be used to monitor soil quality; evaluate residual effects of slash-and-burn; and establish P and K fertilizer equivalence values of ash from slash-and-burn. Each experimental site was divided into 3 blocks within which treatments were randomly allocated. Broadcast burning and pile burning were carried out as practiced by local farmers. Soil samples were collected before burning (control), immediately after burning (burned) and one year after burning and cropping (burned-cropped), hereafter referred to as treatments. Soil samples were analyzed following standard analytical methods. P and K fertilizer equivalence values of the soil tests immediately before burning and after one year cropping of burned land were established and compared. The most sensitive soil properties to slash-and-burn were coarse silt, fine silt, pH, organic carbon (OC), total N (totN), P, Ca, Mg, K, Na, exchange acidity, effective cation exchange capacity (ECEC) and base saturation (BS). Between 47 and 87% of increases in content of exchangeable bases and available P resulting from burning of forest vegetation cover is lost after one year of cropping positive. Benefits in soil P and K attributed to slash and burn agriculture after one year cropping in terms of fertilizer equivalence was between 1 to 18 kg P2O5&nbsp;and 22 to 76 K2O. P and K fertilizer recommendations for targeted crop yields based on the initial soil fertility status of the secondary forest in the humid forest zone of Cameroon should be 9 kg P2O5&nbsp;and 49 kg K2O less in the second year of cropping. &nbsp; Key words: Slash-and-burn, soil properties, humid forest zone, shifting cultivation, Southern-Cameroon.

Exploring vulnerability and adaptation to climate change of communities in the forest zone of Cameroon

Understanding vulnerability to the impacts of global environmental change and identifying adaptation measures to cope with these impacts require localized investigations that can help find actual and exact answers to the questions about who and what are vulnerable, to what are they vulnerable, how vulnerable are they, what are the causes of their vulnerability, and what responses can lessen their vulnerability. People living in forests are highly dependent on forest goods and services, and are vulnerable to forest changes both socially and economically. In the Congo basin, climate change effects on forest ecosystems are predicted to amplify the existing pressure on food security urging expansion of current agricultural lands at the expense of forest, biodiversity loss and socioeconomic stresses. The paper aimed at exploring vulnerability and adaptation needs to climate change of local communities in the humid forest zone of Cameroon. Field work was conducted in two forest communities in Lekie and in Yokadouma in the Center and Eastern Regions of Cameroon respectively. The assessment was done using a series of approaches including a preparatory phase, fieldwork proper, and validation of the results. Results show that: (a) the adverse effects of climate conditions to which these communities are exposed are already being felt and exerting considerable stress on most of their livelihoods resources; (b) drought, changing seasons, erratic rain patterns, heavy rainfall and strong winds are among the main climate-related disturbances perceived by populations in the project sites; (c) important social, ecological and economic processes over the past decades seemed to have shaped current vulnerability in the sites; (d) Some coping and adaptive strategies used so far are outdated; and specific adaptation needs are identified and suggestions for facilitating their long-term implementations provided.

Preliminary Diagnosis and Recommendation Integrated System (DRIS) Norms for Hevea brasiliensis Grown in the Humid Forest Zone of Cameroon

Preliminary Diagnosis and Recommendation Integrated System (DRIS) Norms for Hevea brasiliensis Grown in the Humid Forest Zone of Cameroon

Institutional choice and local legitimacy in community-based forest management: lessons from Cameroon

SUMMARYDecentralization of forest management has become a common policy globally which has allowed communities to regain rights removed through colonization and central state management of forests. However, socioeconomic and environmental outcomes of such community-based forest management schemes have been mixed. Studies have shown the importance of institutions in influencing the success of these new governance arrangements. Based on an extensive literature review supplemented by qualitative research, using focus groups and semi-structured interviews, conducted in nine villages in the humid forest zone comprising three community forests, this research investigated the successes and challenges from decentralization of forest management in Cameroon. A key constraint on success was the inappropriate institutional structure at the local level with responsibility to manage community forests. Community forest management committees with no internally recognized legitimacy and dominated by local elites had replaced roles once played by traditional authorities. Qualitative research showed that in the humid forest zone of Cameroon, the system of accountability for forest resources, prior to the enactment of community forest legislation, included those with historical traditional cultural authority, in the form of clan or lineage heads, as well as the village chief, a legacy of colonial power. Village chiefs or other members of the village council are also selected on the basis of their good moral character. Community forest management committees that are a hybrid of customary authorities and other representatives of the population chosen following the criteria for local legitimacy may capture the best of historical social regulation and build on it so that the local committee may be seen as being accountable to the local population. Since such hybrid institutions are not without their risks, it is important that these institutions be accountable to a local democratic government to further increase their transparency and accountability. Models of community-based natural resource management that incorporate culturally appropriate requirements of legitimacy and accountability in crafting local institutions may have more success in accomplishing both socioeconomic and environmental goals.