Cultural practices such as organic manure application can affect soil fertility and also insect pest and disease incidence on the plant. The effect of poultry manure application was therefore evaluated in relation to the infestation by major insect pests and disease of pepper in a humid tropical agro-ecosystem. Treatments comprised three varieties of chilli pepper, Capsicum annum vars. tartashi and tarugu and Capsicum frutescens var. Birds eye chilli, and three Poultry Manure (PM) rates: 0, 20, and 40 t ha-1 , in all possible combinations. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. Poultry manure (PM) used was found to be high in nitrogen (2%) but very low in available phosphorus (0.05 ppm) and potassium (0.24 meq/100g soil) as evidenced from the chemical analysis. Aphids (Myzus persicae Sulzer and Aphis gossypii Glov.), mirids (Helopeltis schoutedeni Reuter), flea beetles (Nisotra=Podagrica sjostedti Jacoby and Podagrica uniforma Jacoby), variegated grasshoppers (Zonocerus variegatus L.), white flies (Bemisia tabaci Genn.) and striped blister beetles (Epicauta albovittata Gestro) were the insect pests sampled from the plants in the field. Symptoms of Pepper Veinal Mottle Virus (PVMV) were also evident. All the varieties were susceptible to PVMV with a disease incidence of between 37 and 45%. Counts taken at 100 days after transplanting (DAT) showed that increasing rates of poultry manure significantly (P<0.05) increased aphid, mirid and grasshopper infestations as well as incidences and severities of Pepper Veinal Mottle Virus (PVMV) symptoms compared to where no manure was applied. The different varieties significantly (P<0.05) affected the infestations by insect pests as well as the incidences and severities of PVMV symptoms, such that PVMV symptoms and insect pests were found to be more on "Birds eye chilli", a local pepper variety, than any other given the same treatment. Poultry manure and variety interactions were significant (P<0.05) on some insect populations, incidences of PVMV symptoms and yield attributes. Counts of Bemisia tabaci at 100 DAT and number of aborted fruits, on the other hand, did not differ significantly amongst the manure levels, varieties and their interactions. However, there was a progressive trend of increasing Bemisia infestation with increasing manure rate. Poultry manure at 20 t ha-1 produced the highest fruit weight. These results are discussed in light of soil fertility on the susceptibility of chilli pepper to insect pests and disease in this agro-ecology.

Ecosystem engineers such as ants and termites play an important role in the fertility of tropical soils. Physicochemical analyses were thus carried out on some arboreal ant nests collected from mango (Mangifera indica), bush mango (Irvingia gabonensis), kola (Cola nitida), newbouldia plant (Newbouldia laevis), and oil bean plant (Pentaclethra macrophylla) and on ground nest of termite,Odontotermes sudanensisSjost. (Isoptera: Termitidae) in Nigeria. Arboreal nests, particularly those ofM. indica, were significantly richer in the chemical constituents sampled, compared to those of ground-termite nests or adjacent unaffected soils. Available water capacity of nests fromM. indica(60.0%) was significantly higher than those of other sites or locations sampled. While biogenic structures were sandy-loamy in texture, their corresponding adjacent soils were either sandy or sandy-loamy. Soils worked by ants and termites had greater proportions of silt-sized (17.9 versus 9.7) and clay-sized (19.2 versus 9.3) to the detriment of coarse-sized particles (51.2 versus 60.9) and fine-sand-sized particles (11.7 versus 20.1) relative to the adjacent soils. Generally, biogenic structures were about 348% richer in P than their corresponding adjacent soils; an attribute, which holds a strong promise in bioremediation and biofortification of soils especially during amendment.

The widespread adoption of cropping systems that are sustainable and environmentally friendly is vital for the macroeconomic survival of civilization. Intercropping could ensure stability of insect populations in a system. , and variegated grasshoppers (Zonocerus variegatus) were the crop's seedling pests and caused minimal damage. Clavigralla spp. infestations were high at the reproductive stage causing 24% and 29% seed damage in regular and ratoon pigeon pea crops, respectively. Maize slightly suppressed insect pest incidence and damage to pigeon pea pods and seeds but significantly (P < 0.01) reduced grain yield in the regular pigeon pea crops in 2005 and 2006, although not in the 2007 ratoon. The pigeon pea genotypes differed significantly (P < 0.05) in pest incidence at the podding stage in both the regular and ratoon crops and in grain yield (P < 0.01) for the regular crop. Grain yield of the pigeon pea ratoon crops was about 60% of the regular crop. Farmers were recommended to adopt the ICPL 161 and ICPL 87 genotypes based on pest tolerance and high grain yield or as idiotypes in pigeon pea hybridization programs.

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Nitrogen fertilization and spacing hold a strong promise in the integrated management of rice insect pest problem. Therefore, three levels of urea: 0, 80 and 160 kg N ha-1 and three spacings: 10-cm x 10-cm, 20-cm x 20-cm and 30-cm x 30-cm were evaluated for two years in Abakaliki, Nigeria, for the control of rice gall midge. The experiment was set up using split-plot arrangement in a randomized complete block design (RCBD) with three replications. Results of the trial showed that nitrogen significantly increased incidence by gall midge (P<0.05) with 160 kg N ha-1 recording the highest incidence of 50.95% and 36.01% in 2002 and 2003 trials, respectively. Similarly, incremental doses of urea n-fertilizer increased the grain yield of rice but only up to 80 kg N ha-1. Beyond this level further n-fertilization had no effect. Generally, increasing plant population significantly increased the incidence by the midge (r = 0.93 and 0.99 in both years). Conversely, grain yield was significantly reduced with increasing population. Differences among treatment combinations between nitrogen and spacing however did not produce any significant effect.