Esther Kahangi

University · horticulture

The effect of inoculation of microorganisms-based commercial products on post-flask management and field establishment of tissue cultured (TC) banana plantlets was investigated. TC banana cv. Gros Michel plantlets were inoculated with Bacillus, mycorrhizal and Trichoderma based products in a Vertisol, Humic Nitisol, Rhodic Ferralsol and conventiona...

The impact of microbiological commercial products (PHC Biopak, Rhizatech and ECO-T) on the occurrence of mycorrhizae and Fusarium in the rhizosphere of tissue culture banana (Gros Mitchel cv.) was assessed. Tissue cultured banana plantlets were inoculated with PHC Biopak (Bacillus), Rhizatech (mycorrhiza) and ECO-T (T. harzianum) under greenhouse c...

The impact of microbiological commercial products (PHC Biopak, Rhizatech and ECO-T) on the occurrence of mycorrhizae and Fusarium in the rhizosphere of tissue culture banana (Gros Mitchel cv.) was assessed. Tissue cultured banana plantlets were inoculated with PHC Biopak (Bacillus), Rhizatech (mycorrhiza) and ECO-T (T. harzianum) under greenhouse c...

Endophytic colonization by the fungus Fusarium oxysporum can result in increased host resistance to pests and diseases, and greater biomass production. However, few studies have assessed the field performance of this fungus for biological control of pests and diseases in banana. Further to greenhouse assessment, studies were carried out to evaluate...

Rice (Oryza sativa L.) is the most important staple food crop in many developing countries, and is ranked third in Kenya after maize and wheat. Continuous cropping without replenishing soil nutrients is a major problem in Kenya resulting to declining soil fertility. The use of chemical fertilizers to avert the problem of low soil fertility is curre...

The use of tissue culture (TC) banana (Musa spp.) planting material is an effective method of providing pest and disease-free plants. Although there are many added benefits to using TC plants, the adoption of TC technology remains relatively low in East Africa. Currently, adoption is increasing under impetus from the private sector. Adopting TC ban...

The effect of inoculation of microorganisms-based commercial products on post-flask management and field establishment of tissue cultured (TC) banana plantlets was investigated. TC banana cv. Gros Michel plantlets were inoculated with Bacillus, mycorrhizal and Trichoderma based products in a Vertisol, Humic Nitisol, Rhodic Ferralsol and conventiona...

The root-lesion nematode Pratylenchus goodeyi is a common pest of banana in Kenya, which results in significant yield losses. An emerging option for the management of banana nematodes includes the use of endophytic fungi, which cause no damage to their hosts but often extend benefits, such as enhanced protection against various biotic and abiotic c...

The status of arbuscular mycorrhizal fungi (AMF) in banana and plantain (Musa spp.) farming systems was studied in central Kenya. Soils and roots were sampled from 50 farms. Mean colonization frequency and intensity of 56.9% and 36.8% signified presence of viable infective propagules. Total of 22 morphotypes were recovered and six identified to kno...

Macadamia is the most important nut crop in Kenya with an estimated annual production of about 13,510 metric tones with an estimated value of $ 4.8M. The cultivated macadamia is derived from two species; the rough-shelled M. tetraphylla and the smooth shelled M. integrifolia. The Kenyan macadamia industry relies on selection of superior trees from...

Laboratory studies have revealed great potential of entomopathogenic fungus Beauveria bassiana for use against the banana weevil, Cosmopolites sordidus, in banana. Adult banana weevils exposed to wet conidia of Beauveria bassiana suffered high mortalities ranging from 50-70% by 40 days post exposure when a concentration of 1×10 9 was used in the la...

Bananas and plantains are widely grown in tropical countries by smallholder farmers who depend on them for their livelihood. In Kenya the crop is harvested throughout the year and ensures food and income security thus playing an important role in poverty alleviation. In recent years there has been a rapid decline in banana production, due mainly to...

Fruit bagging during growth is practiced on some fruit crops in Australia and Japan to control damage by physiological and pathological disorders. This study was undertaken to investigate whether this treatment could be used to control lenticels discoloration, a physiological disorder unique to 'Apple' mango, a popular cultivar in Kenya, which has...

Banana is an increasingly demanded food and cash crop in sub-Saharan Africa. Reported yields in smallholder farms vary substantially. The importance and spread of yield constraints have not been properly quantified. A study was carried out in Central Kenya to (i) quantify the yield levels, the primary yield constraints, and the spatial production g...

The use of tissue culture (TC) technology to propagate banana plants gives growers several advantages over the conventional propagation. This technology is an indispensable tool for the facilitation of quick, and en masse, multiplication of adequate planting material of indigenous and exotic banana (Musa spp.) clones and production of disease-free...

Growth patterns of plant crop of banana (Musa spp.) cultivars 'Grande Naine' and 'Williams' (AAA genome), grown in Maragwa, Central Kenya in 2006 and 2007, were determined to establish the best maturity indices to determine harvest time. The banana plants were randomly selected from an already existing orchard where the farmer followed the recommen...

Macadamia, (Macadamia spp.) is conventionally propagated by grafting scions from selected superior cultivars onto rootstocks raised from seed, a process that takes about two years in addition to high inputs thus ending up with costly seedlings. A study was conducted to investigate the possibilities of applying tissue culture techniques in mass prod...

Three bioassays were conducted to investigate the antagonistic effect of secondary metabolites produced by 5 endophytic Fusarium oxysporum isolates from banana (Musa spp.) plants in Kenya, against Pratylenchus goodeyi. Percentage paralyses were recorded 3, 6 and 24 h after exposure to culture filtrates. Percentage mortality was evaluated after 48 h...

Macadamia (Family Protaceae) is the most important nut crop in Kenya, grown as a source of household income and foreign exchange. Kenya is the fourth largest producer of Macadamia nuts contributing about 10% of world's total production. However, its production, expansion and commercialization are hampered by various constraints, especially suitable...

The distribution of contaminated planting material (suckers) remains a major cause of spread of pests and diseases in banana. A traditional subsistence staple in East Africa, banana is becoming increasingly a commercialized commodity in the region. Essential for effective commercialization of this crop, however, is the supply and use of uniform and...

The distribution of contaminated planting material (suckers) remains a major cause of spread of pests and diseases in banana. A traditional subsistence staple in East Africa, banana is becoming increasingly a commercialized commodity in the region. Essential for effective commercialization of this crop, however, is the supply and use of uniform and...

Preharvest cultural practices affect the postharvest quality and behaviour of many fruits. In this study we compared the postharvest behaviour and quality of mango (Mangifera indica L. cv. 'Tommy Atkins') fruit from irrigated and non-irrigated trees. The trees were subjected to water stress (non-irrigated) up to 42 days after bloom (DAB) and contro...

This study aimed at understanding the quality characteristics of mango (Mangifera indica L. cv. 'Tommy Atkins') fruit from trees subjected to water stress (non-irrigated) during the first phase of growth (up to 42 days after bloom). Selected physico-chemical and physiological parameters were monitored at two weeks interval from fruit set up to 168...

Experiments were conducted to investigate the antagonistic effects of secondary metabolites produced by endophytic Fusarium oxysporum against Helicotylenchus multicinctus spiral nematode of banana. Endophytic F. oxysporum were isolated from healthy bananas sampled from Kilifi district in Kenya. Five endophytic isolates of F. oxysporum were selected...

A study was carried out to investigate the effect of culture medium factors that influence the shoot regenerative potential of Macadamia nodal segments in vitro. Explants were obtained from shoots of current growth flush of Macadamia integrifolia and inoculated onto different test media. Woody plant medium (WPM) gave results comparable to MS medium...

The ability to identify genetic variation is indispensable to effective management and use of genetic resources. Morphological traits are among the earliest markers used in germplasm characterization and management. Leaf and fruit morphological characteristics were recorded for 23 cultivars of Macadamia using a sample of 30 for each trait and repli...

The potential of cassava starch as an alternative and cheap gelling agent for potato in vitro culture micro-propagation media was investigated. A two-factor experiment in randomized complete block design was conducted. Four levels of gelling agents; 10% (w/v) cassava starch, 8% cassava starch mixed with 0.25% agar, 0.8% agar and a liquid medium, we...

Macadamia, a member of the family Proteaceae, is widely grown in Kenya as an alternative cash crop to tea and coffee, but varieties adapted to different agro-ecological zones are still lacking. Macadamia breeders require high genetic diversity to select and recombine favorable traits through cross-breeding and hence the need for in situ conservatio...

A polymerase chain reaction (PCR)-based approach, namely, random amplified polymorphic DNA (RAPD) was used to estimate the genetic relationships among 20 selected banana cultivars from different regions of Kenya. Nineteen random primers were used. The polymorphisms in PCR amplification products were subjected to the unweighted pair group method for...

Seventeen Musa cultivars that were rated highly by the small-scale farmers in Kenya were examined for random amplified polymorphic DNA (RAPD) genetic markers using PCR with ten 10-mer primers. The aim of the study was to sort out synonyms and enable in vitro production of true-to-type plants. The study included five reference cultivars of genomic g...

This study was carried out with the objective of determining the optimum reaction conditions for the polymerase chain reaction (PCR) in Musa germplasm. DNA was extracted from young leaves and purified. Amplification reactions were carried out with different concentrations of taq DNA polymerase, MgCl₂ as well as template DNA for the PCR....

Effect of natural chilling and artificial chilling durations of 2-8 weeks at 9°C on percentage bolting and flowering and on days taken from planting to the two events in carrot cv. Nantes was observed at four locations in Kenya in 1991/92. These were; Juja (1500 m above sea level in a warm Upper Midland (UM) zone) and Molo (2454 m), Kinangop (2558...

The effect of chilling alone or in combination with gibberellic acid (GA3) and benzyladenine (BA) on runner production in three strawberry cultivars was observed during the warm and cool seasons in a field experiment under tropical conditions in Kenya. Chilling alone promoted a significant production of 18 and 10 runners per mother plant in the col...

A survey was carried out to determine the locally available leafy vegetables in three locations of Machakos District, Kenya. The most common vegetables were analyzed for vitamin C, beta‐carotene calcium, iron and oxalate. Consumption of wild and semi‐wild leafy vegetables was found to be common in the three locations especially during the dry seaso...

In Kenya, at Kabete (1941 m), GA3 applications at 100 and 250 mg 1−1 promoted flowering in cabbage cvs Sugar Loaf and Giant Drumhead but cv Golden Acre did not flower. The same levels of GA3 promoted flowering in kale cv Collards, but failed in cv Thousand Headed. There was a small percentage of natural flowering in all cabbage and kale cvs that fl...

Effect of temperatures on bolting and flowering, measured as days to internode extension (bolting) and to flower bud visibility, respectively, were studied in carrot (Daucus carota) cultivar (cv.) "Nantes" grown in a controlled environment. All carrot plants raised from stecklings subjected to 10 weeks chilling at 3, 6 and 9 C bolted and flowered u...