Research Article
Effects of Organic Fertilizers on Growth, Yield and Quality of Strawberry (Fragaria × ananassa) VAR. Chandler in Nakuru, Kenya
Issue:
Volume 12, Issue 1, February 2026
Pages:
1-11
Received:
6 November 2025
Accepted:
17 November 2025
Published:
30 January 2026
Abstract: A field experiment was carried out during the 2024/2025 season at Baraka Farm in the Lanet area of Nakuru County, Kenya, approximately 10 kilometers northeast of Nakuru city center. The study aimed to evaluate the effects of different fertilizers, BSF frass (black soldier fly excreta), KUZA, and NPK 17:17:17 on the growth, yield, and postharvest quality of the Chandler strawberry variety under field conditions. A randomized complete block design (RCBD) with three replicates was used. Data were collected on the number of leaves and flowers, plant height, yield, total soluble solids (TSS), firmness and titrable acidity. Results indicated that the number of leaves and flowers per plant, plant height was significantly (p ≤ 0.05) influenced by both season and fertilizer treatment. NPK (17:17:17) consistently produced the highest leaves counts at all growth. High fruit firmness values were obtained in the strawberries subjected to NPK 17:17:17 followed by BSF frass. BSF frass also resulted in relatively high acidity suggesting it can maintain acidity close to that of NPK. Application of frass, particularly from BSF frass substrates, led to improved strawberry vegetative growth, higher yields, and enhanced postharvest fruit quality. The study offers important insights into the potential of BSF frass as a suitable organic fertilizer, its role in reducing synthetic inputs and its contribution to improving both productivity and quality of strawberry.
Abstract: A field experiment was carried out during the 2024/2025 season at Baraka Farm in the Lanet area of Nakuru County, Kenya, approximately 10 kilometers northeast of Nakuru city center. The study aimed to evaluate the effects of different fertilizers, BSF frass (black soldier fly excreta), KUZA, and NPK 17:17:17 on the growth, yield, and postharvest qu...
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Research Article
Quantification of β-Cyfluthrin Residues on Field-Grown Kale and Collards Greens
George Fouad Antonious*
Issue:
Volume 12, Issue 1, February 2026
Pages:
12-22
Received:
7 November 2025
Accepted:
12 January 2026
Published:
11 February 2026
DOI:
10.11648/j.ijaas.20261201.12
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Abstract: Pyrethroids such as β-cyfluthrin are synthetic analogues of the natural pyrethrins that are extracted from the flower of Pyrethrums (Chrysanthemum cinerariaefolium and C. coccineum). β-cyfluthrin is a commonly used insecticide on brassica leaves to control insects attack such as Lepidoptera, Coleoptera, Hemiptera, and Diptera families for better crop yield and quality. A field study was conducted to investigate the dissipation pattern of β-cyfluthrin on collard and kale leaves following spraying of the commercial formulation Baythroid® XL. The objectives of the study were to determine the dissipation constants and half-life (T½) values of β-cyfluthrin on kale and collard grown under field conditions and to determine the workers' re-entry time following β-cyfluthrin spraying for workers and consumer safety. Following spraying, residues of β-cyfluthrin were extracted from the leaves using ethyl acetate and cleaned up through an open glass chromatographic column packed with Florisil. Quantification and confirmation of the insecticide residues were carried out using a gas chromatograph (GC) equipped with an electron capture detector (GC/ECD) and a GC equipped with a mass selective detector (GC/MSD), respectively. The method successfully separated the 4 isomers of β-cyfluthrin, revealing the molecular ion fragments at m/z of 127, 163, 206, and 226, respectively. Following spraying, the initial residues (sum of isomers) of β-cyfluthrin were lower on collard (9.5 µg g-1) than on kale leaves (28.8 µg g-1 fresh leaves). The study revealed a greater T1/2 value of 8.2 days of β-cyfluthrin on collard than on kale leaves (5.1 days).
Abstract: Pyrethroids such as β-cyfluthrin are synthetic analogues of the natural pyrethrins that are extracted from the flower of Pyrethrums (Chrysanthemum cinerariaefolium and C. coccineum). β-cyfluthrin is a commonly used insecticide on brassica leaves to control insects attack such as Lepidoptera, Coleoptera, Hemiptera, and Diptera families for better cr...
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