Postharvest losses of bulb onion (Allium cepa L.) in selected sub-counties of Kenya

Inappropriate postharvest practices such as unsuitable harvesting methods and inadequate curing in bulb onion lead to losses. Postharvest losses in bulb onion contribute to food and nutrition insecurity. Although Kenya has suitable environmental conditions for bulb onion production, its productivity is low, which is attributed to pre- and postharvest factors. Information on bulb onion postharvest losses and their causes in the country is scanty which limits development of postharvest losses reduction strategies. Therefore, this study was carried out in three major bulb onion growing sub-counties of Kenya namely Mt. Elgon, Buuri and Kajiado East to determine postharvest practices, causes and factors influencing postharvest losses of bulb onion. A multi-stage sampling design was used to select the study areas and a total of 166 respondents were randomly selected. Face-to-face interviews were conducted using a structured questionnaire to collect information on postharvest handling practices, postharvest loss levels and their causes at farm level. Data were subjected to descriptive and logistic regression analysis using Statistical Package for Social Scientists (SPSS) software version 2.0. Results indicated that 68% of the respondents were males and with an average age of 40 years in the three sites. Forty eight percent of the respondents used leaves toppling, and 25% used drying of upper leaves as maturity indices. About 42% of the respondents used machete (panga) as a harvesting tool which significantly (P<0.05) influenced postharvest losses. Seventy seven percent of the respondents indicated that up to 30% postharvest losses occurred at farm level. Forty percent of the respondents indicated that bulb onion rots caused 10 % loss at farm level. The level of education, and mode of transport (bicycles and donkeys) significantly (P<0.05) influenced postharvest losses. It was concluded that the postharvest losses at farm level was 30% and were mainly caused by rotting. Socio-economic characteristics and postharvest handling practices nfluenced bulb onion losses at farm level. Development of postharvest losses reduction strategies on bulb onions focusing on alleviating rotting through appropriate postharvest handling practices at farm level was recommended

Identification of Xanthomonas vasicola (formerly X. campestris pv. musacearum), causative organism of banana xanthomonas wilt, in Tanzania, Kenya and Burundi

Article purchased; Published online: 28 Feb 2010Xanthomonas campestris pv. musacearum (Xcm) causes a disease onbanana (Musa spp.) and enset (Ensete spp.) known as banana xanthomonaswilt (BXW). Recent studies have shown that Xcm is a strain of X. vasicola(Aritua et al., 2008). However, the status of pathovars within thespecies remains unclear. Prior to its discovery in Uganda in October 2001,the disease had been limited to Ethiopia (first reported 1968). Since thenthe disease has spread to the Democratic Republic of Congo and Rwanda(observed in May 2004 and September 2005 respectively). BXW cancause high yield losses and is a high priority concern within the GreatLakes region. A comprehensive review of the pathogen and diseasewas recently published by Smith et al. (2008). Thus far, outbreaks inTanzania, Kenya and Burundi have only been referred to in symposiumproceedings and on various websites. These new records are thus officiallyreported here for the first time.In Tanzania, the disease was first reported in the Kagera region of northwest Tanzania, bordering Lake Victoria, Uganda, Rwanda and Burundi,in September 2005 (Mgenzi et al., 2006). Spread has continued, but not toother major banana growing areas. In Kenya, the disease was firstreported in September 2006 in the Teso District, of western Kenya,bordering Uganda (Anon, 2006). Spread has since been reported as slow.In Burundi the disease was first observed during October 2006 (Anon.,2006). The current status of BXW in Burundi is unclear with no recentsubstantiated reports.Bacterial cultures were isolated from diseased racemes from Tanzaniaand Burundi at CABI, UK and from Kenya at KARI (NARL). All cultureswere identified to species level at FERA by fatty acid profiling (MIDI system)and DNA analysis using X. vasicola specific primers (Aritua et al.,unpublished data) and partial sequencing of the gyrase B gene (Parkinsonet al., 2007). Koch’s postulates were fulfilled for all strains at FERA bystem inoculation of banana plants (height approximately 30 cm) with abacterial suspension (200 lL with ~107 cfu ⁄ mL) under controlled environmentalconditions (minimum temperature 27ºC). Identification ofXcm isolates from Burundi and Kenya was further supported by OhioState University and KARI, respectively, using X. vasicola specific primers(Lewis-Levy Miller, unpublished data) that have a different target site tothose of Aritua et al. (unpublished data).Reference cultures are held by the UK National Collection of PlantPathogenic Bacteria, Accession Nos. NCPPB 4392-5 (Tanzania), 4434(Kenya) and 4433 (Burundi)