EFFECTS OF ORGANIC MANURES ON GROWTH, YIELD AND QUALITY OF GYPSOPHILA (GYPSOPHILA PANICULATA L.)
Abstract
Cost effective and environmentally friendly crop production using a variety of animal manures is possible for all horticultural production systems including floriculture. Efficient production of summer cut flowers like gypsophila is feasible under small-holder production system. The objective of this study was to determine the effect of different types and application rates of animal manures on growth, yield and quality of gypsophila cut flowers grown under field conditions. The experiment was carried out in the Horticulture Department Farm, Faculty of Agriculture, Luyengo Campus of the University of Swaziland to determine the growth, yield and quality of gypsophila when fertilised with kraal manure, poultry manure and inorganic fertilisers. The treatments were kraal manure applied at 10, 20, 40 and 80 t/ha; and chicken manure applied at 5, 10, 20, and 40 t/ha. A control of inorganic fertiliser (2:3:2 (22) + 5% Zn) was applied at 1,400 kg/ha. The design of the study was a Randomised Complete Block Design (RCBD). Data collected was subjected to analysis of variance (ANOVA). Where significant results were obtained, means were separated using the Duncan’s New Multiple Range Test (DNMRT). The results showed that chicken and kraal manure levels affected growth of gypsophila, with chicken manure at 40 t/ha inducing the highest plant height of 54.7 cm followed by kraal manure applied at 80 t/ha (52.6 cm). The lowest plant height of 38.4 cm was observed in plants applied with the inorganic fertiliser. Plants supplied with chicken manure at 40 t/ha had the highest cut flower length of 53.9 cm followed by kraal manure at 80 t/ha with 48.6 cm whilst inorganic fertiliser induced the lowest cut flower stem length of 37.5 cm. Gypsophila applied with chicken manure at 40 t/ha had the highest number of marketable cut flowers (7.1) followed by kraal manure at 80 t/ha with 6.7 cut flowers. Plants supplied with inorganic fertiliser had the lowest number of marketable cut flowers (5.1). The application of chicken manure at 40 t/ha induced the highest fresh and dry masses whilst inorganic fertiliser application resulted in the lowest values. There were no significant differences in the accumulation of N, P, and K in gypsophila plants due to the different treatments. It was concluded, therefore, that farmers should use chicken manure applied at 40 t/ha or kraal manure applied at 80 t/ha for profitable production of gypsophila under field conditions in Eswatini.