Though the majority of people in Kenya and at Kopsiro Division in particular, rely on ethnomedicinal plant species to manage human ailments, the indigenous knowledge largely remains undocumented. Therefore, an ethnobotanical study was conducted on medicinal plant species used to manage human ailments at Kopsiro Division Mt. Elgon District Kenya. The objectives were to identify and document plants traditionally used for medicinal therapy by the Sabaots, to find out the method used for preparing and administering the drugs and to find out the conservation practices for the medicinal plants. Observations and semi-structured interviews were used to gather ethnobotanical data. 107 plants belonging to 56 families were identified and reported to be of medicinal value to the locals. Roots (47.3%) were the most frequently used parts of the plant followed by the bark (23.35%) then leaves (22.75%). The whole plant (1.8%), seed (1.2%), fruit (1.2%), sap (1.2%), flower (0.6%) and wood (0.6%) are least used in that order. The study revealed other hitherto undocumented medicinal plant species that may be new records for treating various ailments. Traditional medicine in Kopsiro division offers cheap, accessible and convenient remedy that suits the traditional lifestyle of the local community in comparison to the conventional medicine. Most medicinal plant species reported in this study were found to be under threat and this calls for urgent conservation measures so as to maximize the sustainable use of these vital resources in the study area.

Striga spp. is renowned for causing great losses in cereal production in sub-Saharan Africa. Crop competitiveness with parasitic weeds such as Striga is an important criterion for selection in an initiative to produce and release rice cultivars to farmers that are able to give high and stable yields under low-input conditions. The symptoms of Striga infected rice plants are chlorosis, wilting and stunted growth. Rice yield is reported to be reduced by more than 50% in areas that are infested by the weed. In addition, areas that are heavily infested have been abandoned and rendered unfit for crop production. Notable advances in Striga weed control technology have been made, yet the weed continues to be a major cause of low agricultural production. This is an indication of poor linkage between research institutions and agricultural extension which is a bottleneck to research findings to benefit farmers.

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Striga spp. is considered to be the greatest biological constraint to food production in sub-Saharan Africa, a more serious problem than insects, birds and plant diseases. They are among the most specialized root-parasitic plants inflicting serious injury to their host depriving them water, minerals and photosynthate. The greatest diversity of Striga spp. occurs in grassland. However, Striga hermonthica mainly occurs in farmland infecting grasses. The parasite devastating effect is accomplished prior to its emergence from the soil. It may cause yield losses in cereals ranging from 15% under favourable conditions to 100% where several stress factors are involved, thereby affecting the livelihood of millions of resource-poor farmers. Piecemeal approach to address one aspect of Striga problem at a time has been a setback in technology transfer to producers. Future Striga control programs should not be conducted separately, but should rather be conducted in an integrated approach that combines research talents of various institutions. This will facilitate collaborative research and achieve qualitative interaction between stakeholders, which can easily produce reliable technologies that are practical and available to farmers. Striga being a pervasive pest, time is of essence in controlling it. There is an urgent need for the establishment of policies to promote, implement, and ensure a long-term sustainable Striga control program.

Crops grown in salt affected soils may suffer from drought stress, ion toxicity, and mineral deficiency leading to reduced growth and productivity. The present study was conducted to determine how salinity affects growth, water relations, and accumulation of cations of nutritional importance in various organs of grain sorghum [Sorghum bicolor (L.) Moench]. Two Kenyan sorghum varieties, Serena and Seredo, were grown in a greenhouse in quartz sand supplied with a complete nutrient solution to which 0 (control), 50, 100, 150, 200, and 250 mM NaCl was added. The 250 mM NaCl treatment significantly reduced the relative shoot growth rates, measured 25 d after the start of salt application, by 75 and 73%, respectively, for Serena and Seredo, and stem dry weight by 75 and 53%. In a similar way, young leaves were affected, with leaf blades of both varieties being reduced by 67% while sheaths were reduced by 83 and 87% for Serena and Seredo, respectively. Leaf water potential, osmotic potential, leaf pressure potential, and relative water content significantly declined with increasing salt stress. Roots and stems accumulated substantial amounts of sodium, saturating at 150 mM external NaCl. Accumulation of K+ and Ca2+ in the roots, stems, and leaves was strongly inhibited by salinity. Magnesium concentration of the roots was minimally impaired but that of the stems and leaves was strongly affected. Leaves continuously accumulated sodium, which was preferentially deposited in the sheaths. Mature leaves contained more Ca2+ and Mg2+ than young ones. The two sorghum varieties appear to sequester Na+ predominantly in roots, stems, leaf sheaths, and older leaf blades sparing the growing tissues as a salt tolerance mechanism. Nevertheless, greatly reduced concentrations of Ca2+, K+, and Mg2+ in leaves under salinity could cause cation deficiency which reduces plant growth.