Influence of Lime and Fertilizer Application on Growth and Yield of Dry Bean (Phaseolus Vulgairs L.)

Abstract

Dry bean (Phaseolus vulgaris L.) is an important legume crop in the world. The crop is widely cultivated in both developed and developing countries. In Kenya, dry bean is a staple food crop, which comes second after maize as a source of calories, and its production is partially constrained by soil acidity and infertility. The study evaluated the effects of liming, farmyard manure, and inorganic fertilizers on the growth, nodulation, and yield of dry beans. The experiment was set up in a randomized complete block design with a split-plot arrangement, conducted over two rainy seasons at two locations, Kenya Agricultural and Livestock Research Organization (KALRO)- Embu and Mwea in Embu County and Kirinyaga County respectively. Two improved bean varieties namely KATB1 and TASHA were tested. The amendments used comprised the application of agricultural lime (5 t ha-1), goat manure (10 t ha-1), phosphorus (40 kg ha-1), potassium (60 kg ha-1), and nitrogen (20 kg ha-1) both singly and in combination while control plots had no external amendments. Data was collected on plant height, nodulation, pest incidence, disease incidence, shoot biomass, yield, and yield components. Soil samples (before planting and after harvest) and manure samples were taken and tested for total nitrogen, potassium, available phosphorus, calcium, magnesium, organic carbon, and pH. After harvest, plant tissue was taken and analyzed for P, N, and K content. Application of Lime, goat manure, P, N, and K had no significant effects on all the chemical properties of soil in Embu and Mwea, except that, the application of goat liming significantly increased soil magnesium in Mwea. Significant effects of agricultural lime and goat manure were detected on all plant parameters. A single application of lime and goat manure in combination with NPK fertilizers recorded taller plants and a higher number of formed nodules at vegetative and flowering growth relative to control and NPK treatments in both sites. Application of goat manure singly recorded a higher number of pods per plant and higher shoot biomass relative to control and NPK treatments. Seed weight and grain yield were higher in plots amended with sole lime and manure than in control plots and plots amended with NPK treatments. Application Lime increased the grain yield four-fold. Nitrogen, P, and K treatments showed no significant effects on plant height, nodule number, pod number, and shoot biomass. TASHA and KATB1 varieties had no differences in grain yield components in the two sites and seasons. The KATB1 variety recorded a higher number of seeds per pod, pod weight, pod number, and shoot biomass in KATB1 than the TASHA variety in Embu and Mwea during the long rains. During the long rains, variety and soil amendment interactions significantly 2 affected bean shoot biomass and grain yield in Mwea. KATB1 variety recorded higher shoot biomass and grain yield weight in plots treated with lime followed by plots treated with manure compared to control and P, K, and N treatment. The application of the treatments had no significant effects on root rot and bean fly incidences during the experiment. A positive relationship was identified between yield and seed weight linear relationship (R2 ranged between 0.663 and 0.889). The results demonstrate that a single application of lime and manure and their combination with NPK significantly affected all the collected data except, pest and disease incidents that were not significates affected. As per that, lime and goat manure can be used to develop nutrient and low pH management options to improve dry bean productivity