Browsing by Author "Hatibu, Asha Ally"

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    Challenges facing effective use of bat guano as organic fertilizer in crop production: a review
    (International Journal of Engineering and Applied Sciences, 2021) Marwa, Ernest Melkiory; Andrew, Twisege; Hatibu, Asha Ally
    Bat guano is excrements of bats and it is commonly used in agriculture as a soil amendment and sometimes as a pesticide in organic farming. Small-scale farmers nearby guano deposits use it for indoor and outdoor plants as well as for hydroponic crop production. Guano in soils acts as a source of carbon (C) and energy to drive microbial activities as well as a precursor to soil organic matter fractions. With all these benefits, bat guano should be used in crop production with some precautions. Chemical composition and properties of bat guano are not fixed and are changing with time depending on the maturity, reaction with the country rock and bat diet. The pH of guano changes from alkaline to strongly acid with maturity. Similarly, guano loses some essential plant nutrients on decomposition and sometimes acquires potentially toxic elements as it reacts with the host rocks. Amounts added to the soil also vary with maturity and composition of guano. Thus, utilization of bat guano as organic fertilizer requires a thorough and regular characterization at the time of using it as soil amendment for crop production
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    Tanzanian bat guano as an alternative source of phosphorus for organic rice production
    (International Journal of Plant & Soil Science, 2021-11-29) Hatibu, Asha Ally; Shitindi, Mawazo Jamson; Marwa, Ernest Melkiory
    Many tropical and subtropical soils are low in phosphorus. This is partly because of excessive weathering, high phosphorous (P) fixation rates, and low P levels in soil parent materials. Continuous removal of P from soils by crops, coupled with limited application of P fertilizers, is also among the contributing factors for low P in soils. Phosphorus is among the most limiting macronutrient in rice (Oryza sativa L.) production. This study was conducted to evaluate the suitability of bat guano collected from Kisarawe (BGK-A and BGK-B) and Sukumawera caves (BGS) in Tanzania. The screen-house experiment at the Sokoine University of Agriculture was designed as a 4 × 6 factorial experiment conducted as a randomized complete block design (RCBD). Guano and triple superphosphate (TSP) were used as standard fertilizer at six P application rates. The yield of rice in response to applied TSP was comparable to applied guano but in the order TSP > BGK-A > BGS > BGK-B. All parameters increased with an increase in applied amounts of P from guano and TSP. Besides this study revealed the significant (P = .05) interaction between P sources and P rates on plant height (PH), micronutrient concentration and dry matter (DM). The study showed the correlation between grain yield (GY) and other crop components of dry matter (DM), the number of panicles (NP), Panicle height (PAH), plant height (PH) and number of tillers (NT). A significant and positive correlation was found for the GY-DM (r = 0.58, P = .05), GY-PAH (r = 0.65, P < .001), and GY-NT (r = 0.420, P = 0.1). But strong positive correlation was found between GY-PH (r = 0.76, P < .001) and GY-NP (r = 0.84, P < .001). It was concluded that studied guanos can be used as an alternative source of P, especially for smallholder farmers.