Changes in leaf yield and nutritive quality of the black nightshade (solarium nigrum) as influenced by nitrogen application
Date
1996Author
Murage, Ephraim N
Chweya, James A
Imungi, Jasper K
Type
ArticleLanguage
enMetadata
Show full item recordAbstract
The effect of nitrogen application rates on the leaf yield and nutritive quality of the black nightshade (Solatium nigrum L.), an indigenous Kenyan leafy vegetable was investigated. Application of 5 g N per plant gave the highest fresh leaf yield of 19 and 40 tons/ha after 10 and 12 weeks of growth, respectively. The dry matter and crude fibre contents decreased with increasing nitrogen rates. With a supply of 5 to 15 g N per plant, the dry matter and crude fibre contents were on average 8.3% and 17.8 g/100 g dry matter. The crude fat and protein contents increased with nitrogen supply. Plants treated with N fertilizer yielded about 60% more proteins than the control plants grown with zero g N. The level of (5‐carotene in the leaves increased by about 60% from 63 mg/100 g fresh weight with zero g N to 103 mg/100 g fresh weight with 5 g N per plant. Although, the ascorbic acid content increased by over 100% in plants grown with 5 g N per plant, thereafter, a declining trend was observed with higher rates of N supply. Nitrogen application had little effect on the levels of potassium, calcium and magnesium in the leaves. In addition, no major effect of nitrogen supply was observed on the levels of oxalates and phenolic compounds. However, the accumulation of nitrate‐nitrogen (NO3‐N) in the leaves was greatly enhanced by nitrogen application. In leaves of plants supplied with 5 g N, the amount of NO3‐N was ten times more than in the control plants. Important aspects on the dietary contribution of S. nigrum leaves are also discussed.
URI
http://www.tandfonline.com/doi/abs/10.1080/03670244.1996.9991484#.UbV9NpwkbfIhttp://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/30442
Citation
Murage, E.N, Chweya, J.A & Imungi, JK(1996). Changes in leaf yield and nutritive quality of the black nightshade (solarium nigrum) as influenced by nitrogen application. Ecology of Food and Nutrition, 35(2):149-157.Publisher
Department of Plant Science and Crop Protection, University of Nairobi Department of Food Science, Nutrition and Technology, University of Nairobi
Subject
Ascorbic acidP‐carotene,
Black nightshade,
Leaf yield
Nitrates
Nitrogen
Nutritive quality
Phenolics
Oxalates
Solanum nigrum
Description
Journal article