Nigerian Guinea Savanna Research Articles

Architectural Responses of Cashew to Intercropping and Nutritional Amendments in Nigerian Guinea Savanna Agro Ecology

Field experiment was conducted at Cocoa Research Institute of Nigeria sub-station Ochaja, to evaluate the impact of manure and intercrops on cashew tree growth, canopy development and yield. Treatments consisted of Bambara and Sesame intercrops and manuring using Cocoa pod husk (CPH) and NPK fertilizer applied at the rate of 0, 1,713kg and 400kg/ha respectively. The experiment was laid out in a split-split plot design with three replications and monitored within the two years of study. Data collected includes: Plant height, Stem girth and canopy North-South/East-West direction. These was used to calculate: crown diameter, canopy spread, canopy volume, canopy ground cover and canopy ground cover percentage. The results showed that the growth characters of Cashew were positively influenced by alley crops of Sesame and Bambara nut and manuring. Manuring with CPH exerted differences in the responses of cashew to alley crops, in particular, canopy development. Intercropping with a combination of bambara-sesame and the application of NPK fertilizer proved to have the highest Cashew growth development but showed no significant differences on the yield and yield attribute. The GGE biplot results identified the best intercrop system for each of the three-fertilizer type treatment. Within the two years of the experiment, Cashew development was not hampered by the introduction of the different intercropping systems.

Assessment of Yield and Nutritional Qualities of Local and Improved Maize Varieties Cultivated in Wukari and Environement of the Nigerian Guinea Savanna Agro-Ecology

Assessment of Yield and Nutritional Qualities of Local and Improved Maize Varieties Cultivated in Wukari and Environement of the Nigerian Guinea Savanna Agro-Ecology

ClasSoil Genesis in Volcanic Areas of the Jos Plateau, Nigeria.sification of soils planted with orange (citrus sinensis) and mango (mangifera indica) in the Nigerian guinea savanna

The purpose of this study was to explain the genesis of soils formed in the volcanic areas of the Jos Plateau, Nigeria. Ten soil profile pits, representing the various landscape segments of a typical volcano and a lava plain, were dug, described and sampled for physical, chemical and mineralogical analyses. The results show early, moderate and advanced stages of soil development on the cones, upper / middle footslopes and toeslopes, respectively, indicating that soil maturity stage increases from the crest down to the toeslopes. Amorphous clay minerals are found in the young soils while kaolinite dominates the clay fraction in the mature ones. Similarly, soil pH, organic carbon, exchangeable bases and CEC decrease as soil maturity increases. The important soil forming processes in the study area include addition of organic matter, clay formation from hydrolytic weathering, soil structure formation, clay migration (eluviation and illuviation), acidification, loss of basic cations through leaching, gleying, ferralization and allitization. The major weathering process is that of hydrolytic weathering of the pyroclastic materials, including basaltic rocks, pumice, lava and ash. Soil erosion and aeolian sedimentation have affected the soils. Intensive weathering and leaching precluded the formation of 2:1 clay minerals. In the same vein, because of the effects of tropical climate the soils could not meet the requirements of Andisols.Key words: Soil genesis, Soil properties, Volcanic areas, Jos Plateau, Nigeria.

Decomposition Patterns of Selected Organic Materials in the Nigerian Guinea Savanna

Decomposition Patterns of Selected Organic Materials in the Nigerian Guinea Savanna

Reactions of plantain and banana cultivars to black sigatoka leaf spot disease in three farming systems in the Nigerian guinea savanna

An assessment of the severity of black sigatoka (BS), Mycosphaerella fijiensis, leaf spot disease on plantain and banana was undertaken in three farming systems in the Guinea savanna environment of Nigeria. The three farming systems were field sites, backyard sites and fadama sites. The plant crops cycle was divided into periods before flowering, at flowering and at harvest. Host response was measured throughout the stages of growth. Both symptom evolution time (Set) and incubation time (It) were faster after flowering than periods before flowering. The severity was significantly higher (p lt 0.05) in plantains and sweet bananas grown in outlying fields than in those in backyards and fadamas. At all the study sites, Bs was less severe on cooking bananas than on plantains and sweet bananas. Also, no significant differences were observed in Bs severity on cooking bananas grown in any of the three study sites, suggesting that the resistance is more of genetical than site effect. Thus, while breeding and genetic selection remain the most effective strategy against Bs, less disease develops on susceptible cultivars when they are cultivated on sites rich in organic matter.

Technical and economic evaluation of some Striga control packages in maize in the Nigerian Guinea Savanna

Earlier reports have confirmed the technical feasibility and socio-economic acceptability of some integrated Striga control packages (ISCOPA) at farmers’ level. However, the performance of ISCOPA based on the synthetic varieties of maize have not been consistent. With the development of new open pollinated low management requiring Striga-tolerant maize varieties, further evaluation of the new packages has become necessary. In 1995, farmer-managed trials were, therefore, conducted at two locations Dakachi and Kaya in the Northern Guinea Savanna (NGZ) of Nigeria to compare the new ISCOPAS with the promising one reported earlier and relate crop yield to Striga/weed complex parameters. The ISCOPA tested had tolerant maize varieties, fertilizer application, weed control (pre-emergence herbicide application or hoe-weeding) and additional Striga control (post-emergence herbicide or hoe-weeding) as components. The ISCOPAs that had post-emergence herbicide components resulted in significantly higher maize grain yields than the farmers’ practice. Striga infestation was also significantly lower with the ISCOPAs containing post-emergence acifluorfen compared with the farmers’ practice. When three hoe-weedings replaced herbicide applications, only ISCOPAs of maize varieties 9022-13, Oba Super II and Acr 92 TZE produced higher yield than the farmers practice. Among the varieties, Oba Super 1 and 2 supported lower Striga shoot emergence than the farmers’ practice. However, all the improved varieties exhibited lower Striga syndrome reaction compared with farmers variety. The full ISCOPAs effectively reduced Striga shoot count and weed cover score and resulted in higher maize grain yield than the farmers’ practice. Maximum gross and net revenue were recorded from ISCOPAs containing codal (Metolachlor+Prometryne 1.0+1.0 kg a.i./ha) followed by post-emergence acifluorfen. The treatment also gave the highest return per naira invested in the control of Striga/weed complex.

Effect of P fertilizer application on N balance of soybean crop in the guinea savanna of Nigeria

Soybean ( Glycine max (L.) Merr.) is becoming increasingly important in the cereal-based cropping system of the Nigerian Guinea savanna zone and this justifies research on its effects on soil N. Although soybean can obtain 50% or more of its N requirement from the atmosphere, the N contribution of the crop to the system depends on the amount of N contained in roots, haulms, and fallen leaves after grain harvest. At four sites in the northern Guinea savanna, the effects on N balance of P fertilizer and soybean varieties of different duration were tested. The varieties received P fertilizer at the rates of 0, 30, and 60 kg P ha −1. The total N accumulated aboveground at harvest averaged 104 kg N ha −1 in the early and medium varieties, and 135 kg N ha −1 in the late varieties. Across all varieties and sites, total N content was increased by 40–47% when P was applied. Apparent N harvest index averaged 85% but was not significantly affected by variety or P rate. When only grain was exported, the calculated N balance of the early and the medium varieties was −2.6 to −12.2 kg N ha −1 while the longer duration varieties had positive N balances ranging from 2 to 10.9 kg N ha −1. The N accrual was negative when P was not applied and ranged from 2.4 to 5.2 kg N ha −1 with P application. The interaction of variety and site on the N balance was significant at P<0.05. N balance at the southernmost site was −14.2 kg N ha −1 compared with 2.6–10 kg N ha −1 at the northern sites where N 2 fixation was higher. The estimate of N balance is reduced when soybean haulms are exported. A positive N contribution by soybean is, therefore, possible in a soybean–cereal rotation when: (i) P is applied, (ii) the soybean variety is late maturing, and (iii) only grain is exported.

Biomass, protein, fibre and lignin production responses to varying soil texture and precipitation for a humid Nigerian savanna

:Herbaceous biomass, protein, fibre and lignin production responses to varying soil texture and precipitation was examined on soils with comparable climate in Nigerian Guinea Savanna. The aim was to find out how the yield and chemical constituents of grasses and forbs growing on soils of different soil particle size react to annual variation in rainfall. Samples were collected semi-systematically at peak standing biomass from three 1-ha plots for three years, oven-dried at 80°C, weighed and analyzed for crude protein, fibre and lignin. Grass yield decreased and forb yield increased with increase in rainfall in soils with high clay and silt contents and vice-versa in soils with high sand content. Crude protein and structural constituents (fibre and lignin) of most of the plant species were higher in the year with lower rainfall than in that with heavier rainfall. It is concluded that grasses and forbs respond differently to annual rainfall variation and their response is determined by soil texture.

Effect of tree canopy cover on the yield, crude protein and fibre content of forb species in Nigerian Guinea savanna

The relationship between tree canopy cover and forb species in savanna was investigated by examining the effect of tree canopy cover on the yield, crude protein, fibre and lignin content of forb species.

Comparative rate of rot-induction by nine fungal pathogens on stored tomato fruits in Nigeria

The rate of rot-induction by nine of the most important fungal pathogens responsible for field and storage rots of tomato fruits in the Nigerian Guinea Savanna, was compared in the laboratory. The pathogens were, Furarium equiseti, F. oxysporum, F. chlamydosporium, Exserohilum rostratum, Rhizopus stolonifer, Colletotrichum capsici and Aspergillus niger. There was a very highly significant difference ( P = 0.001) in the rate of induction of rot by the different fungi. R. stolonifer induced rots faster than all the other fungi, while E. rostratum and C. lunata were the slowest in inducing rots. The control fruits remained healthy for most of the 10-day trial period. It was concluded that the virulence of the infecting pathogen is a factor determining the shelf life of tomato fruits.

Body temperature responses of Savanna Brown goat to the harmattan and hot-dry season

Rectal and vaginal temperature responses of the Savanna Brown goat indigenous to the Nigerian guinea savanna were determined during the harmattan and the hot-dry season. Measurements were made at 06:00h and at 14:00h after 8h exposure to field conditions. At the 06:00h measurements during the harmattan, all animals were observed to shiver. A significant (P<0.01) positive correlation was found between rectal (Tre) and vaginal temperatures. During the harmattan, mean Tre was 38.2‡C at 06:00h and 39.7‡C at 14:00h; the mean difference, δTre was 1.5‡C. During the hot-dry season, Tre at 06:00h was 38.1‡C, and at 14:00h, 38.7; δTre was 0.6‡C. It is concluded that the harmattan is thermally more stressful than the hot-dry season and that passive thermolability may not be an important mechanism in the Savanna Brown goat in adaptation to thermal stress.

Effect of season on estrous cycle of Yankasa sheep

An investigation was conducted to establish the effects of harmattan and hot-dry season on estrous cycle length, onset, and duration of estrus in Yankasa sheep indigenous to the Nigerian guinea savanna zone. Mean cycle lengths were 16.8 ± 0.58 and 16.4 ± 0.53 days during harmattan and hot-dry seasons, respectively; short cycles, 5–13 days, and long cycles, 21 to 30 days, were observed during both seasons. During the harmattan season, 57.1% of estrus began at night while 70% started at night during the hot-dry season. The duration of normal estrus observed during the harmattan, 33.6 ± 5.87h, significantly decreased (P0.05) during the hot-dry season (24.0 ± 5.45h). It is suggested that twice daily observation at 12-hour intervals will suffice to detect estrus in this breed of sheep.

Environmental profile and milk production of Friesian-Zebu crosses in Nigerian Guinea Savanna

A 10-year meteorologic data have been collated to enable delienation of the environmental profile of the Nigerian Guinea Savanna zone. Three distinct seasons are defined: a hot-dry season which lasts from March to April; a hot-humid season (May to October); and the harmattan season (November to February). The effects of these seasons on milk production by half and three-quarter Friesian-Zebu crosses were evaluated during the first 100 days of lactation over a 2-year period. There were no significant differences in milk yield between the genotypes, but at heat intensities above 27‡C, the half cross gave more milk than the three-quarter cross. It is thus recommended that the half Friesian-Zebu cross be selected for milk production in the Nigerian Guinea Savanna and that suitable husbandry and managerial adjustments such as provision of adequate clean water, shelter, good quality and silage and night grazing should be evolved to ameliorate the adverse effects of thermal stress and nutritional deficiency during the drier and hotter months of the year.

Foraging, recruitment and emigration inMegaponera foetens (Fab.) (Hymenoptera: Formicidae) from the Nigerian Guinea Savanna

In southern Guinea Savanna (Nigeria)Megaponera foetens attacks foraging Macrotermitinae. Termites are located by single major workers — “scout ants”. Marking experiments confirmed that the scout ant also guided the columns of ants to the termites. Regional differences in foraging and recruitment in the species thoughout the African savannas are compared.