Comparative Effects of Different Organic Manure on the Growth, Proximate, Mineral and Phytochemical Compositions of Launaea taraxacifolia (Wild.) Amin Ex. C Jeffrey (African Lettuce)

Background and Objective: Launaea taraxacifolia is one of the several leafy vegetables recently gaining more attention due to its numerous uses. Thus, this study assesses the comparative effects of different organic manure on the growth, proximate, mineral and phytochemical compositions of Launaea taraxacifolia. Materials and Methods: Seeds were obtained from Lagos State Agricultural Input Supply, pig manure, cow dung and poultry manure were collected from a local farm in Lagos State. Growth experiments on Launaea taraxacifolia were carried out in response to different organic manures at the Botanical garden, Department of Botany, Lagos State University, Ojo and harvested leaves were subjected to proximate, mineral and phytochemical analyses using standard procedures. Data collected were subjected to Analysis of Variance (p<0.05) with SPSS version 23. Results: The morphometric analysis revealed that seedlings of L. taraxacifolia grown with pig manure had the highest significant values, as the leaves were broader, lengthier and numerous except stem height which favoured seedlings grown with cow dung. Proximate analyses revealed that poultry manure improved significantly the carbohydrate (30.760.37%) and crude fat (1.890.10%) contents while cow dung improved protein (4.940.19%), Ash (4.290.09%), moisture (56.430.55%) and crude fibre contents (7.130.97%). Mineral analyses revealed that K (119.29 mg kgG 1 ), Mn (0.34 mg kgG 1 ), Na (66.35 mg kgG 1 ) and Ca (88.19 mg kgG 1 ) were significant for plants fertilized with poultry manure. Mg (23.73 ppm) and Zn (0.91 mg kgG 1 ) were significant for plants fertilized with pig manure while P (54.09 mg kgG 1 ) and Fe (0.83 mg kgG 1 ) were significant for plants fertilized with cow dung. Phytochemical analyses revealed the presence of tannins (34.36872.34 mg/100 g), phenols (48.871.42 mg/100 g), saponins (47.90871.81mg/100 g), steroids (26.71872.07 mg/100 g), flavonoids (58.97872.57 mg/100 g), terpenoids (27.8287 2.14 mg/100 g), cardiac glycosides (36.24873.27 mg/100 g) and reducing sugar (50.44872.64 mg/100 g) which are significantly higher in seedlings treated with cow dung. Conclusion: This study, therefore, concludes that pig and cow manure should be used for the probable growth and nutrient enhancement of this plant.