Open Access Original Research Article
Aims: A study was carried out in the field aims to study the response of a calcareous soil cultivated by soybean to the application of K-silicate (K-Si), K-humate (K-H), and compost at application rates 50% and 100% of the recommended dose.
Study Design: Complete randomized block design with three replicates.
Place and Duration of Study: At El-Nubaryia Agricultural Research Station (latitude of 30° 30°N longitude of 30° 20°E) Agricultural Research Center (ARC), Nubaryia, Egypt (Summer seasons of 2018 and 2019).
Methodology: Compost was mixed with surface soil a week before cultivation at application rates 3.75 and 7.5 kg plot-1 (3.91 and 7.81 t ha-1, respectively). Powder K-H was spread on soil at application rates 7.5 and 15 g plot-1 while aqueous solutions of K-Si; 8 and 16 mL L-1 for plot was sprayed on soil 30, 60, and 90 days after cultivation.
Results: Results showed that soil moisture(SM, %) was increased by the 100% application rate in the order compost (20.6%) > K-Si (19.3%) > K-H (19.1%). A significant increase was found in the seed yield (kg ha-1) by 129.5%, 84.8% and 70.6% by compost, K-H and K-Si, respectively. Compost at 100% application rate showed the most significant increase in the available nitrogen N (mg kg-1) in soil by 104.4% followed by K-H (by 81.8%) then K-Si by 23.4%. Compost also showed the most significant increase in the N uptake from soil (kg ha-1 soil) by seeds and straw followed by K-H then K-Si. The nutrient use efficiency (NUE, %) and agronomic efficiency (AE) values decreased in the order K-H > K-Si > compost at 50% and 100% application rates.
Conclusion: The quite smaller dose and ease of field application by spraying may make the K-H more agronomically efficient than K-Si and compost.
Open Access Original Research Article
Arbuscular mycorrhizal (AM) fungi occur over a wide range of agro climatic conditions and are geographically ubiquitous. Arbuscular mycorrhizal fungi are the medium of soil structure, they determine the flow of water, nutrients, and air, directs the pathways of root growth, and opens channels for the movement of soil animals. As the moderator of the microbial community, they also determine the metabolic processes of the soil. In other words, the mycorrhizal network is practically synonymous with ecosystem function. The tremendous advances in research on mycorrhizal physiology and ecology over the past 40 years have led to a greater understanding of the multiple roles of AMF in the ecosystem. The current study was informed due to the depletion of nutrients and poor soil microbiology in tea production whose production has declined in the recent years. The trial was conducted in the research and development greenhouse at the James Finlays Farm in Kericho County, Kenya. The experiment was laid out in a Randomized Complete Block Design (RCBD) with factorial arrangements of tea clones and mycorrhizae levels. The phosphorus treatments consisted of a standard rate of 107.66kg ha -1, two clones of the tea (S15/10 and SC 12/28) and two mycorrhizal strains (Funneliformis mosseae and Glomus intraradices) at two rates (50 kg ha-1 and 70 kg ha-1) and an untreated control without mycorrhizae. The soil pH was positively influenced by reducing the acidity content significantly where mycorrhizae strains were introduced with the highest unit change (1.3) was recorded on clone SC 12/28 at the 50 kg Mycorrhizae ha-1 rate. The same treatment also significantly increased the soil total phosphorus level (2.3 g/kg) compared to all other treatments with the least change observed on the control. Application of AMF strains Glomus intraradices and Funneliformis mosseae is recommended in tea production at the rate of 50 kg ha-1 which improves and enhances the general positive characteristics of soil health.