The effect of farmyard manure and calcium ammonium nitrate on vegetative growth, leaf yield and nutritive quality of Cleome gynadra (Cat Whiskers) in Keiyo District, Rift Valley Province

Abstract

African leafy vegetables (ALVs), which have been neglected by policy makers, researchers, extension workers and farmers, are receiving renewed interest as a possible intervention to food insecurity and malnutrition among resource-poor farmers. A study was carried out with the objective of determining the effects of various levels of farmyard manure and calcium ammonium nitrate (CAN) on vegetative growth, yield and quality (vitamins A and C and nitrates) of Cleome gynandra in Keiyo District, during long and short rains of the year 2002. The experimental layout was a RCBD with four replicates. The treatments were four levels of farmyard manure (FYM; 5, 10, 15, 20 t/ha) and four rates of CAN (100, 200, 300, 400 kg/ha). The addition of various rates of FYM and CAN that were tested significantly improved vegetative growth and increased leaf yields of Cleome gynandra. The yields obtained from plants grown with FYM were generally higher than from those with CAN. The incorporation of either FYM or CAN increased vitamin A content in both seasons. During Season 1, FYM increased vitamin C content in both young and older tissues, while CAN had no effect on the same. The application of 300 kg/ha of CAN increased the accumulation of nitrates in young and old tissues, while FYM had no effect on the same. In conclusion, fertilizer type and rate of application, season, plant age and management had a significant influence on vegetative growth, leaf yield and quality of Cleome gynandra.