Jacinta Muiruri; Agnes Kavoo; Mwashasha Rashid Mwajita; Fredah K. Rimberia; Tofick B Wekesa
Abstract
Arbuscular mycorrhizal fungi (AMF) are associated with plant roots and exhibit beneficial impacts such as stress tolerance, better nutrient uptake, and water absorption. These functions have opened the door to research opportunities for considering other fungi associated with AMF on the root rhizosphere. ...
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Arbuscular mycorrhizal fungi (AMF) are associated with plant roots and exhibit beneficial impacts such as stress tolerance, better nutrient uptake, and water absorption. These functions have opened the door to research opportunities for considering other fungi associated with AMF on the root rhizosphere. This study aimed to characterize fungal isolates associated with rhizospheric indigenous AMF from different plant species, i.e., banana, grass, and papaya, in three agroecologies, i.e., Mwea, Mitunguu, and Juja in Central Kenya. A total of 30 fungal isolates were isolated from soil samples through the pour plate technique. The isolates had diverse microscopic morphological characteristics, describable in form, margin, color, size, and surface. Physiochemical parameters showed varied growth at different pH values, temperatures, and salinity levels. Optimal growth appeared at pH 7.0, 30-35 °C, and 0-0.5 M NaCl salinity. The internal transcribed spacer (ITS) and AMF subunit sequences showed a level of diversity similar to Aspergillus spp. Ajellomyces spp., Fusarium spp., Trichoderma spp., Penicillium spp., Glomus spp., and Diversispora spp. In conclusion, there was a symbiotic relationship between AMF and other fungal isolates.
Sloane Wairimu Mungai; Cornelius Mbathi Wainaina; Agnes Mumo Kavoo; Mwashasha Rashid Mwajita
Abstract
Potato is an important tuber crop that has a unique role in the food security of sub-Saharan Africa. Potato production faces several challenges, including limited sources of clean seed and the occurrence of nutrient deficiencies in plants. The availability of clean and viable seeds is the most prevalent ...
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Potato is an important tuber crop that has a unique role in the food security of sub-Saharan Africa. Potato production faces several challenges, including limited sources of clean seed and the occurrence of nutrient deficiencies in plants. The availability of clean and viable seeds is the most prevalent challenge which necessitates the development of new strategies for enhancing production. Understanding the link between in vitro nutrient enhancement and seedling vigor in field conditions can assist in mitigating the adverse effects of these challenges after micro plant transplanting. In vitro experiments were set up to investigate the effects of calcium (Ca) fortification on several potato varieties, i.e. ‘Shangi’, ‘Unica’, and ‘Dutch Robjyn’ regeneration and microtuberization. Cuttings were subcultured onto modified MS media containing five levels of CaCl2 8.8 g L-1, 10.4 g L-1, 12 g L-1, 13.6 L-1, and 15.2 g L-1. Microtubers were initiated on media with 60 g L-1 brown sugar and 6 mg L-1 6-Benzylaminopurine. The experiment was set up in a completely randomized design with three replications. The regeneration capacity of the tested varieties differed significantly, as evidenced by shoot (p=0.0002) and root count (p=<.0001). The response of plants to fortification was variably dependent. The application of 10.4-13.6 g L-1 led to a significant increase (p<0.05) in root count in all three varieties. Furthermore, 13.6 g L-1 CaCl2 led to an increase in root-zone and mid-stem Ca content by 45%, 202%, and 165% in ‘Shangi’, ‘Unica’, and ‘Dutch Robjyn’, respectively, compared to the control. The ‘Dutch Robjyn’ and ‘Shangi’ performed optimally in terms of regeneration and microtuberization, compared to ‘Unica’, under theeffect of 10.4-13.6 g L-1 CaCl2. The results confirmed the optimization of MS regeneration by Ca enhancement as a potential technology for scaling up the production of clean quality seeds.
