Alternaria leaf spot of cabbage, caused by the Alternaria brassicicola, affects leaves of cabbages and often results in head rots causing severe decline in yield. In this work, the effects of systemic and combination fungicides on A. brassicicola mycelia growth in vitro and disease severity in field trials were investigated. The results of in vitro evaluation revealed that both fungicides significantly inhibited (p < 0.05) the growth of A. brassicicola under in vitro conditions. However, metalaxyl-M 6% was less effective with 100 μg/mL having only 30 ± 3.5% inhibition. On the other hand, 100 μg/mL of mancozeb 63% + carbendazim 12% had 94 ± 3.5% growth inhibition of A. brassicicola, respectively, under the same conditions. Dose-response analysis of the efficacy of the two fungicides showed that the LC₅₀ of metalaxyl-M 6% and mancozeb 63% + carbendazim 12% were 125.52 ppm and 57.22 ppm, respectively, indicating the superiority of combination fungicide over systemic fungicide alone. Field studies showed that while manure type significantly impacted on biomass production (p < 0.001), it did not significantly affect disease severity. On the other hand, the frequency of fungicide application impacted on disease severity, with biweekly application leading to a significant reduction in disease severity after 10 weeks.

This study examined the effects of various growth conditions on the mycelial development of two fungal Pathogens and evaluated the nutritional makeup of the resulting infected pepper fruits. The study investigated the complex relationships between the nutritional makeup of the host plant and fungus growth. Using a variety of growth media (potato dextrose agar, carrot dextrose agar, cornmeal agar, oatmeal agar, cauliflower dextrose agar, and Sabouraud synthetic nutrient), the growth dynamics of two separate fungal pathogens (Colletotrichum truncatum and Fusarium verticillioides) were investigated. Various growth media had various effects on mycelia growth. For F. verticillioides, oatmeal, and cornmeal agar showed the maximum mycelia growth (90 cm) after 7 days in culture, while for C. truncatum, oatmeal agar and cauliflower dextrose agar produced the same results. In addition, an analysis of the nutritional makeup of pepper fruits infected with the two pathogens showed changes in proximate compositions, vitamins, minerals, and phytochemicals. Inoculated pepper fruits exhibited lower levels of ash, carbs, fat and protein, and higher levels of fiber and moisture. While healthy pepper fruits recorded higher 6.48%, 1.50%, 2.70% and 0.47% of alkaloids, tannin, flavonoid, and saponin respectively, fruits infected with C. truncatum and F. verticillioides recorded 1.8 and 1.60% alkaloids, 0.81 and 0.50% tannin, 0.59 and 0.40% flavonoid, and 0.26 and 0.36% saponin, respectively. Similar patterns were observed for vitamin and mineral contents. By providing insights that could affect agricultural practices and the management of plant diseases, this comparative study advances our understanding of the complex interactions among fungal pathogens, growth media, and nutritional value of infected plant hosts.

This study aimed at determining how different rates of poultry manure affected the growth and production of onions (Allium cepa L.) in wet and dry seasons. The experiment was conducted from July to October 2019 and from January to April 2020 at the Department of Crop Science teaching and research farm, University of Nigeria Nsukka, South Eastern Nigeria. The experiment applied a randomized complete block design with nine replications spread over three blocks. The treatments were four doses of poultry manure (0, 10, 20 and 30 t.ha^-1) tried in two seasons (wet and dry season). Prior to the investigations, soil analysis of the experimental site and poultry manure nutrient content were carried out. The growth pattern and yield was higher during the wet season. Poultry manure at amount of 30 t.ha^-1 gave the best growth attributes (number of leaves, leaf length, and leaf diameter) 14.22, 53.67 cm and 0.88 cm respectively while the 20 t.ha^-1 had the highest plant height and bulb fresh weight, 60.86 cm and 2 kg/plant respectively. The trend was not the same as in dry season planting because 20 t.ha^-1 poultry manure differs significantly from other rates of poultry manure considered. Plant height, leaf length, leaf diameter and bulb fresh weight (57.64 cm, 55.28 cm, 0.84 cm and 0.63 kg/plant respectively) were statistically significantly (p < 0.05) different at 5% probability level. Utilization of 20 t.ha^-1 of poultry manure and planting in wet season gave the best growth and yield of onion vegetable.