Biology subjects

Nthakanio, P. N.

Publications and source records attributed to Nthakanio, P. N..

2 recordsLinked to original sources

bioRxiv2020

FUNGI DIVERSITY IN THE RHIZOSPHERE OF Aspilia pruliseta Schweif . ext Schweif IN THE SEMI-ARID EASTERN KENYA

Semi-arid eastern Kenya is a fragile ecosystem with continuous cultivation of dryland pulses and grains. Farmers use artificial fertilizers most of which are deleterious to the environment. Previous studies have shown that soil microbes in the rhizosphere could be used to sustainably enhance levels of soil mineral nutrients and soil health. However, few studies have examined fungal diversity in the rhizosphere of wild and native Aspilia pruliseta shrub. In this study, amplicons of Internal Transcribed Spacer (ITS) region on Total Community DNA using Illumina sequencing were used to explore the fungal community composition within the rhizosphere. Operational taxonomic units (OTUs) were analyzed using QIIME 1.8.0, taxonomy assigned via BLASTn against SILVA 119 database. Hierarchical clustering was done using R programming software. 72,093, 50,539 and 43,506 sequence reads were obtained from samples MC1a, MC2a and MC3a respectively representing rhizosphere depth 0-20 cm, 21-40 cm and 41-60 cm. A total of 373 OTUs were realized at 3% genetic distance. Taxonomic analysis revealed that the genera Glomus was most prevalent in all soil depths with 85.60 % of the OTUs in depth 0-20 cm, 69.04 % in depth 21-40 cm and 48.45 % in depth 41-60 cm. The results revealed high levels of obligate arbuscular mycorrhiza fungi that if commercially cultured could enhance phosphates uptake in crops.

ecology↗

bioRxiv2019

Production of Hybrid Rice seeds using environment sensitive genic male sterile (EGMS) and basmati rice lines in Kenya

Photoperiod-sensitive genic male sterile rice (PGMS) lines IR-73827-23-76-15-7 S, IR-75589-31-27-8-33S referred to as P1 and P2, and IR-77271-42-25-4-36S, thermo-sensitive genic male sterile (TGMS) line referred to as T were obtained from International Rice research Institute. These lines, collectively known as environment genic male sterile lines, were sown under greenhouse growth conditions where temperatures were more than 34{degrees}C with an objective of inducing complete male gamete sterility in them. Results indicated that high temperature growth conditions induces complete male gamete sterility in both the PGMS and TGMS lines. The impact of this is that, it will be possible to produce pure basmati hybrid rice seed in the tropical regions without contamination with pure breed lines. The male sterile PGMS/TGMS were pollinated with pollen from basmati370 and 217 grown under natural conditions and some hybrid seeds were obtained. This shows that high temperature emasculated the male gametes but not female ones. The conclusion is that it is possible to induce complete male gamete sterility in PGMS and TGMS under greenhouse in tropical growth conditions, and to produce hybrid rice seeds. This makes basmati hybrid rice seed production in Kenya a viable venture.

plant biology↗