Abstract:
Hand weeding is still by far the most widely practiced cultural weed control technique in vegetable production throughout the tropics because of the prohibitive costs of herbicides and fear of toxic residues coupled with the lack of knowledge about their use. Also, fertilizer application has been designed to improve soil nutrients for adequate plant growth and productivity. Field studies were carried out at the Federal University of Technology, Akure, during the early and late planting seasons 2013 to investigate frequency of weeding and application of neem seed cake fertilizer for optimum growth and yield of okra in Akure, southwestern Nigeria. Okra seeds variety, NHAe47-4 were treated to four levels of neem seed cake fertilizer rates (0kg/ha, 100kg/ha, 150kg/ha, 200 kg/ha) and 200 kg/ha NPK as standards and five weeding regimes (weedy check, unwedded till 5 weeks after planting (WAP), weeding once each at 3 WAP and 4 WAP and once at 3 and 5 WAP). The treatment combinations were laid out in a randomized complete block design to give 25 treatments with three replicates giving a total of 75 plots. The growth attributes viz; plant height, number of leaves, stem girth and leaf area differed significantly due to different treatments. These attributes increased significantly owing to the application of neem seed cake which leads to continuous availability of nutrients to the plants as well as appropriate timing of weeding which reduced the influence of weed interference on the okra. Growth and yield components were influenced significantly by the application of neem seed cake and weeding regimes. The highest fruit yield was observed in plots that received 200kg/ha neem seed cake and weeded at 3 and 5 weeks after planting in both seasons. Application of 200 kg/ha of neem seed cake as well as weeding at 3 and 5 weeks after sowing significantly enhanced okra growth and fruit yield in both seasons.
However, plots with low rates of neem seed cake and infested with weeds until harvest produced the least okra growth and fresh fruit yield.
Keywords: NHAE47-4, neem seed cake fertilizer, southwestern Nigeria, weed interference, okra, growth, and yield
