This chapter focuses on the economic importance, damage symptoms, cumulative damage impact and some recommended integrated nematode management programmes of plant parasitic nematodes in smallholder maize cropping systems in East Africa. Information on the various improvements in the current nematode management methods and recommendations for future research are also discussed.

<p><strong>Background</strong>. Soil health assessment has been based on narrow disciplinary approaches that overlook the multiple and interacting biological processes that are the basis of sustainable crop productivity. <strong>Objective</strong>. Determine the influence of seasonal variations in nematode assemblages in different soil groups, sites and disturbance levels as an indicator of soil health. <strong>Methodology</strong>. Sampling was done in areas characterized by small scale subsistence agriculture in Kenyan Northern sites and Southern sites over three distinct seasons. The sampling points included disturbed (tilled) and the adjoining undisturbed (untilled) soils within three soil groups, namely Vertisols, Cambisols and Arenosols. Nematodes were extracted using the centrifugal-floatation technique, enumerated and assigned to their respective trophic groups. <strong>Results.</strong> Total nematode abundance in the three seasons varied significantly (p ≤ 0.05) with a mean of 68, 93 and 52 nematodes in 200 cm³ of soil in seasons I, II and III, respectively. Nematodes abundance in the undisturbed soils was significantly higher (98) compared to the disturbed soils (62) nematodes per 200 cm³). Mean abundance of nematodes was highest in Cambisols. In addition, nematode abundances, in all trophic levels across the three seasons, were significantly higher (p≤0.05) in the northern compared to the southern sites. Bacterivores (28%) had the highest percentage frequency of detection followed by herbivores (27%) and fungivores (21%) while omnivores (11%) had the least. <strong>Implications</strong>. Nematode communities do respond variably to different soil groups and seasonal changes. <strong>Conclusion. </strong> Nematodes can therefore be utilized as viable bio-indicators of soil health and quality.</p>

<p><strong>Background.</strong> Inappropriate agricultural practices such as use of heavy machinery, excessive tillage and unbalanced use of inorganic fertilizers, inappropriate irrigation practices and poor water <em>management</em> techniques, pesticide <em>overuse</em>, inadequate crop residue and/or organic carbon inputs, and poor crop cycling negatively affect soil characteristics. <strong>Objective.</strong> Determine the relationship between soil physical-chemical parameters and nematode assemblages, ecological suitability and nutrient recycling potential as influenced by their respective soil ecosystems. <strong>Methodology.</strong> A total of 576 soil samples were collected in areas characterized by small scale subsistence agriculture in Kenya’s Northern and Southern sites during the cold-dry (1), warm-rainy (2) and hot-dry (3) seasons. The sampling points included land under cultivation (disturbed) and the adjoining natural undisturbed land within three soil groups, namely; Vertisols, Cambisols and Arenosols. Nematodes were extracted, assigned to their respective trophic groups and correlated with analyzed soil chemical properties. <strong>Results.</strong> Omnivores and predators were positively influenced by an increase in Mg and soil organic matter content while an increase in soil pH, K and NH₄contenthad a linear relationship with bacterivores. Increase in Ca and N concentrations was associated with increased numbers of both herbivores and fungivores. Low ecological disturbance and nutrient cycling potential was favored in natural soils, northern sites and where the soils had an active root growth in season 2. <strong>Implications.</strong> Sustainable soil management practices are recommended in a bid to maintain the favorable soil structure through nematode assemblage. <strong>Conclusion.</strong> Changes in soil properties resulting from anthropogenic activities, have a significant impact on nematode assemblages in their respective food webs. <strong></strong></p>