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This experiment was conducted at the Teaching and Research Farm of the Faculty of Agriculture and Veterinary Medicine, Imo State University, Owerri, between May and August 2019. The experiment investigated the effect of garlic (Allium sativum) extracts in the control of maize stem borer (Busseola fusca) in Owerri. The experiment was arranged in a Randomized Complete Block Design (RCBD) with four treatments and three replications. In this trial, various levels of treatments were used. (0ml, 50ml, 100ml, 150ml) and (0g, 50g, 100g, 150g) for crude liquid and crude powder extracts. Proximate analysis was carried out on Allium sativum which revealed the nutritional contents in percentages such as moisture content (62.86), Ash Content (0.90). Phytochemical analysis was carried out which revealed the presence of anti-nutritional constituents in percentages, such as Tannin (0.97), Phenol (0.15), Alkaloid (4.77), flavonoid (1.96), Saponin (1.44), oxalate (3.38), HCN (0.01) and Phytate (0.19). More so, infrared spectroscopy of Allium sativum revealed the presence of bioactive compounds and the different wavelength at which they were absorbed. Such compounds are amines (1032.36 and 3998.00), alkane and alkyl (2935.00), Alkene (1641.00), Aromatic compounds (1406.39), Alcohol (1126.14), Alkyl halides (532.36 and 593.00). data were collected on number of insects, number of plants infested leaf area, leaf area index, plant height, number of leaves, number of fruits per plot, stem girth and fruit yield and subjected to analysis of variance at 0.05% level of significance. The results of the trial revealed that the plots that received 50mls, 100mls and 150mls of crude liquid extracts suppressed number of insects (1.0, 1.3 and 1.0) also, plots that received 50mls, 100mls of crude liquid extract at 1WAT reduced the number of plants infested (0.3 and 0.3) than the crude powder extract (0.6 and 1.0) and these were significantly different (P= 0.05). The lowest mean (51.38kg/ha) and (2.67) in fruit yield and number of fruit per plot were recorded from untreated plots. The plant height showed no significant difference (P≤ 0.05). In this study, Allium sativum reduced the number of insect pests attack (Busseola fusca) on maize plant. This action might be due to the anti-nutritional or bioactive compounds inherent in Allium sativum. [ABSTRACT FROM AUTHOR]

In insect communities, the outcome of intra- and inter-specific competitions for food utilisation depend primarily upon density and duration even inter-specific competitions can occur when they are not sharing the same feeding niche such as between foliar feeders and stemborers. Experimental manipulations of larval densities and the durations of common diet feeding of fall armyworm (FAW), S. frugiperda, and the African lepidopteran stemborers, Busseola fusca, Sesamia calamistis and Chilo partellus, were conducted to determine how the density and the duration of resource utilization affected larval survival and the relative growth rate (RGR) in intra- and inter-specific interactions. The results showed both intra- and interspecific competitions were observed among all the four species and interspecific competition was significantly stronger between the stemborers than between the FAW and the stemborers. The results showed that multiple infestations of cereal plants with low larval densities of each species at optimum conditions will very likely prolong the coexistence between FAW and stemborers. In addition, the time partitioning of the resource use significantly influenced this coexistence. [ABSTRACT FROM AUTHOR]

Ecological intensification utilizes biodiversity to maintain agricultural yields while reducing negative environmental impacts. While pest management is a common goal of ecological intensification, studies examining ecologically intensified pest management systems over longer time scales are rare. Using the push-pull system in Western Kenya, we examine whether pest abundance (for both insects and parasitic weeds) and yield vary with time since a given push-pull field was established. With a total of 1880 data points from 476 unique farmers and 24 cropping seasons, we found that pests declined with time since establishment in both push-pull and nearby control fields, while yield improved with time since establishment in push-pull fields. Although this study did not directly address mechanisms, it seems likely that pests in the push-pull system are not successfully adapting to overcome its pest management effects given the continued declines in pest abundance over time. Our data suggest that ecologically intensified agriculture may be resilient against pest adaptation over time, maintaining consistently high yields. • An agroecological system for maize maintains benefits over several growing seasons. • Analysis included 1880 data points from 476 unique farmers and 24 cropping seasons. • The push-pull system's effects appear to become stronger with time. • Control fields near push-pull fields also have fewer pests as push-pull fields age. [ABSTRACT FROM AUTHOR]

Stem borers are major insect pests of maize in Uganda. A study was conducted in 2014–2016 to assess the performance of Bt hybrids expressing Cry1Ab (event MON810) against the two major stem borer species in Uganda – the African stem borer (Busseola fusca) and the spotted stem borer (Chilo partellus) – under artificial infestation. The study comprised 14 non-commercialized hybrids, including seven pairs of Bt and non-Bt hybrids (isolines), three non-Bt commercial hybrids and a conventional stem borer resistant check. All stem borer damage parameters (leaf damage, number of internodes tunneled and tunnel length) were generally significantly lower in Bt hybrids than in their isolines, the conventionally resistant hybrid, and local commercial hybrids. Mean yields were significantly higher by 29.4–80.5% in the Bt hybrids than in the other three categories of non-Bt hybrids. This study demonstrated that Bt maize expressing Cry1Ab protects against leaf damage and can limit entry of stem borers into the stems of maize plants, resulting in higher yield than in the non-transgenic hybrids. Thus, Bt maize has potential to contribute to the overall management package of stem borers in Uganda. • Bt maize hybrids significantly reduced stemborer damage. • Leaf and stem damage were significantly lower in Bt than in non-Bt maize hybrids. • Bt maize yielded higher than non-Bt maize hybrids by 29.4 to 80.5%. [ABSTRACT FROM AUTHOR]