9 research outputs found
Bananas, Laos and economic development: farming practice and farmers' perceptions
Banana is a crop that has long been important in traditional Lao culture and customs. In more recent times, banana has been identified as an agricultural product with export potential. Accordingly, there has been increasing land use for banana cultivation by local farmers and international investors. This reflects a strategic policy of the agriculture and forestry sectors in contributing to the reduction of rural poverty by generating more income for farmers. Any country seeking to trade agricultural products internationally is obliged to establish pest lists for those commodities. In Laos, however, the study of insect pests of banana and of traditional banana cultivation practices is very limited. This thesis provides the first detailed study on the status of banana growing in Laos as an initial step in developing the banana export market and helping farmers in management and planning.
Data was collated from reports of banana production areas in Laos, including both "grey literature" and published studies of banana pests in Laos and globally, as well as the surveys and field experiments outline in the thesis. Opinions and feedback on the status of banana growing in Laos was also obtained from a variety of forestry departments, research stations and agricultural staff in Laos. Although many studies on banana pests were found, only one, dating from 1978, had been based in Laos. This study listed insects found on economic crops of Laos, but lacked details such as insect biology, impact on crops, sampling methods and illustrations.
Based on an analysis of this data and input from government officials, suitable sampling locations to examine banana farm practices were identified, totalling 22 farms in two provinces Bolikhamxay (central Laos) and Saravan (southern Laos). Details of each farm (size, farm age etc.), and the approaches to banana cultivation practiced (banana species grown, pest status and pest practices etc.) were documented. Two classes of sampling methods were tried: (1) sampling on specific banana plants and (2) opportunistic sampling of non-selected banana plants and surrounding vegetation. The four types of sampling techniques used to collect insects from banana plants were: pyrethroid spray, sticky traps, visual scanning and pitfall traps. The three types of opportunistic sampling used were: scanning (direct observation), examination of cut stems and sweep netting. The field sampling was conducted during the dry season of 2012.
Parallel to field sampling, a questionnaire was designed to assess farmers' understanding and perceptions of banana pests on their farms. The questionnaires were administered in the Lao language to farmers in three provinces; Vientiane Capital, Bolikhamxay and Saravan. Farmers from the sites used for the insect surveys were among those chosen.
Insect specimens collected were transported to James Cook University (Queensland, Australia) for identification. Identifications were based on The Insects of Australia, other available sources and the advice of specialist entomologists (outlined in more detail in the relevant Chapters).
Insects were initially sorted into orders and families. The family-level identity of each taxon was taken as an initial indication of whether it might be a pest. Efforts were made to identify these, focusing on the recognized banana pests already reported from Laos and Southeast Asia. Some specimens were very small (less than two millimetres) and could not be identified. They were named a, b or c, according to their morphological characters.
Characteristics of banana farms in the two major banana-growing regions of Laos are reported. This is an important component of any strategic development of the banana industry. The two largest farms were large-scale commercial enterprises in Bolikhamxay, with a relatively sophisticated management system in place and growing only the Cavendish variety. On the other hand, the majority of farms in both Bolikhamxay and Saravan were small back-yard cultivations, surrounded by other kinds of vegetation and largely un-managed after planting.
A guide to the nine key pest taxa of banana in Laos is presented. These nine taxa were selected based on my field surveys (2 952 samples of insects were studied in detail), feedback from farmers and a study of the literature, both local and global. This guide represents a useful tool to improve the understanding of readers (farmers, agriculture staff and non-specialist users) in Laos. The nine pests were Cosmopolites sordidus (root borer), Odoiporus longicollis (stem borer), Basilepta subcostata (scarring beetle), Chrysomelidae, Acrididae, Erionota thrax (banana skipper), Tephritidae, Bactrocera dorsalis (fruit fly), and Stephanitis typica (lace wing bug). The guide includes useful illustrations, common and Lao names, information on lifecycle, distribution, damage caused, host range, monitoring and control options, as well as references and Lao government sources for further information.
An important element of this thesis was the development of a set of field sampling protocols for detecting the insect pest species determined to be the nine key banana pests of banana in Laos. Observation of cut stems was more likely to detect O. longicollis and C. sordidus than other types of pests. Scan methods showed a bias towards detecting Acrididae, Chrysomelidae and B. subcostata. Sampling using pyrethroid spray was more likely to yield Stephanitis typica on the banana plant and Tephrititidae were most easily caught on sticky traps. However, there was no sampling method that more likely to detect Erionota thrax (banana skipper) and B. dorsalis.
The survey questionnaire results revealed that a typical Lao banana farmer was aged between 41-61 years and that more than half had attended primary school. Banana farms were typically small-scale, around 0.25 hectares or less. Farms were generally on land owned by the farmers themselves. The most common banana variety grown in their farms was Kuay Nam (KN). Farmers perceived that the main pest on their farms was Erionota thrax (approximately 44.8% of total respondents), while other significant pests causing economic losses included scarring beetle, thrips, fruit fly, grasshopper and termites (group 1) (56.3% of total respondents). There was a relationship between the farm size and the type of pest management used by farmers in different locations. If the farm was larger than 0.75 ha, control methods were generally applied (especially against scarring beetle). Although farmers considered that harmful economic pests were present, more than half of the respondents (55.3%) did not try to control the pests. Only a small number of respondents (18.4%) used chemical controls, while the majority employed a variety of manual approaches. Farmers correctly recognized some banana pest taxa, but these were only a subset of the probable pest taxa found during the farm sampling.
The results of this thesis provides the first overview of the status of banana production in Laos, identification of the key insect pest species that impact banana production and the identification tools designed to allow farmers to detect and understand these nine pest species. Together, this information represents the first steps in the advancement of the farmer support network required to develop a long-term and sustainable banana production industry within Laos. Ongoing studies into the taxonomic status of some of the currently unidentified pest species, seasonal and annual changes in pest abundance and the further refinement of pest sampling techniques would all serve to enhance the banana growing industry
Bananas, Laos and economic development: farming practice and farmers' perceptions
Banana is a crop that has long been important in traditional Lao culture and customs. In more recent times, banana has been identified as an agricultural product with export potential. Accordingly, there has been increasing land use for banana cultivation by local farmers and international investors. This reflects a strategic policy of the agriculture and forestry sectors in contributing to the reduction of rural poverty by generating more income for farmers. Any country seeking to trade agricultural products internationally is obliged to establish pest lists for those commodities. In Laos, however, the study of insect pests of banana and of traditional banana cultivation practices is very limited. This thesis provides the first detailed study on the status of banana growing in Laos as an initial step in developing the banana export market and helping farmers in management and planning.
Data was collated from reports of banana production areas in Laos, including both "grey literature" and published studies of banana pests in Laos and globally, as well as the surveys and field experiments outline in the thesis. Opinions and feedback on the status of banana growing in Laos was also obtained from a variety of forestry departments, research stations and agricultural staff in Laos. Although many studies on banana pests were found, only one, dating from 1978, had been based in Laos. This study listed insects found on economic crops of Laos, but lacked details such as insect biology, impact on crops, sampling methods and illustrations.
Based on an analysis of this data and input from government officials, suitable sampling locations to examine banana farm practices were identified, totalling 22 farms in two provinces Bolikhamxay (central Laos) and Saravan (southern Laos). Details of each farm (size, farm age etc.), and the approaches to banana cultivation practiced (banana species grown, pest status and pest practices etc.) were documented. Two classes of sampling methods were tried: (1) sampling on specific banana plants and (2) opportunistic sampling of non-selected banana plants and surrounding vegetation. The four types of sampling techniques used to collect insects from banana plants were: pyrethroid spray, sticky traps, visual scanning and pitfall traps. The three types of opportunistic sampling used were: scanning (direct observation), examination of cut stems and sweep netting. The field sampling was conducted during the dry season of 2012.
Parallel to field sampling, a questionnaire was designed to assess farmers' understanding and perceptions of banana pests on their farms. The questionnaires were administered in the Lao language to farmers in three provinces; Vientiane Capital, Bolikhamxay and Saravan. Farmers from the sites used for the insect surveys were among those chosen.
Insect specimens collected were transported to James Cook University (Queensland, Australia) for identification. Identifications were based on The Insects of Australia, other available sources and the advice of specialist entomologists (outlined in more detail in the relevant Chapters).
Insects were initially sorted into orders and families. The family-level identity of each taxon was taken as an initial indication of whether it might be a pest. Efforts were made to identify these, focusing on the recognized banana pests already reported from Laos and Southeast Asia. Some specimens were very small (less than two millimetres) and could not be identified. They were named a, b or c, according to their morphological characters.
Characteristics of banana farms in the two major banana-growing regions of Laos are reported. This is an important component of any strategic development of the banana industry. The two largest farms were large-scale commercial enterprises in Bolikhamxay, with a relatively sophisticated management system in place and growing only the Cavendish variety. On the other hand, the majority of farms in both Bolikhamxay and Saravan were small back-yard cultivations, surrounded by other kinds of vegetation and largely un-managed after planting.
A guide to the nine key pest taxa of banana in Laos is presented. These nine taxa were selected based on my field surveys (2 952 samples of insects were studied in detail), feedback from farmers and a study of the literature, both local and global. This guide represents a useful tool to improve the understanding of readers (farmers, agriculture staff and non-specialist users) in Laos. The nine pests were Cosmopolites sordidus (root borer), Odoiporus longicollis (stem borer), Basilepta subcostata (scarring beetle), Chrysomelidae, Acrididae, Erionota thrax (banana skipper), Tephritidae, Bactrocera dorsalis (fruit fly), and Stephanitis typica (lace wing bug). The guide includes useful illustrations, common and Lao names, information on lifecycle, distribution, damage caused, host range, monitoring and control options, as well as references and Lao government sources for further information.
An important element of this thesis was the development of a set of field sampling protocols for detecting the insect pest species determined to be the nine key banana pests of banana in Laos. Observation of cut stems was more likely to detect O. longicollis and C. sordidus than other types of pests. Scan methods showed a bias towards detecting Acrididae, Chrysomelidae and B. subcostata. Sampling using pyrethroid spray was more likely to yield Stephanitis typica on the banana plant and Tephrititidae were most easily caught on sticky traps. However, there was no sampling method that more likely to detect Erionota thrax (banana skipper) and B. dorsalis.
The survey questionnaire results revealed that a typical Lao banana farmer was aged between 41-61 years and that more than half had attended primary school. Banana farms were typically small-scale, around 0.25 hectares or less. Farms were generally on land owned by the farmers themselves. The most common banana variety grown in their farms was Kuay Nam (KN). Farmers perceived that the main pest on their farms was Erionota thrax (approximately 44.8% of total respondents), while other significant pests causing economic losses included scarring beetle, thrips, fruit fly, grasshopper and termites (group 1) (56.3% of total respondents). There was a relationship between the farm size and the type of pest management used by farmers in different locations. If the farm was larger than 0.75 ha, control methods were generally applied (especially against scarring beetle). Although farmers considered that harmful economic pests were present, more than half of the respondents (55.3%) did not try to control the pests. Only a small number of respondents (18.4%) used chemical controls, while the majority employed a variety of manual approaches. Farmers correctly recognized some banana pest taxa, but these were only a subset of the probable pest taxa found during the farm sampling.
The results of this thesis provides the first overview of the status of banana production in Laos, identification of the key insect pest species that impact banana production and the identification tools designed to allow farmers to detect and understand these nine pest species. Together, this information represents the first steps in the advancement of the farmer support network required to develop a long-term and sustainable banana production industry within Laos. Ongoing studies into the taxonomic status of some of the currently unidentified pest species, seasonal and annual changes in pest abundance and the further refinement of pest sampling techniques would all serve to enhance the banana growing industry
Intestinal parasitic infections in HIV-infected patients, Lao People's Democratic Republic
HIV infection is an emerging problem in Laos. We conducted the first prospective study on intestinal parasites, including opportunistic protozoa, in newly diagnosed HIV infected patients, with or without diarrhea. The aims were to describe the spectrum of infections, to determine their prevalence and to assess their associations with diarrhea, CD4 cell count, place of residence and living conditions.; One to three stool samples over consecutive days were obtained from 137 patients. The Kato thick smear method, formalin-ethyl concentration and specific stains for coccidia and microsporidia diagnosis were performed on 260 stool samples. Baseline characteristics regarding relevant demographics, place of residence and living conditions, clinical features including diarrhea, were collected using a standardized questionnaire.; The 137 patients were young (median age: 36 years) and severely immunocompromised (83.9% at WHO stage 3 or 4, median CD4 cell count: 41/mm3). Diarrhea was present in 43.0% of patients. Parasite infection was found in 78.8% of patients, infection with at least two species in 49.6%. Prevalence rates of protozoan and helminth infections were similar (54.7% and 58.4% respectively). Blastocystis sp. was the most frequent protozoa (26.3%). Cryptosporidium sp., Cytoisospora belli and microsporidia, found at low prevalence rates (6.6%, 4.4%, 2.9%, respectively), were described for the first time in Laos. Cryptosporidium sp. was associated with persistent diarrhea. Strongyloides stercoralis was the most prevalent helminth following Opisthorchis viverrini (20.4% and 47.5% respectively). The most immunocompromised patients, as assessed by a CD4 count ≤ 50 cells/mm3, were more likely to be infected with intestinal parasites.; HIV infection was mainly diagnosed at an advanced stage of immunosuppression in Lao patients. Intestinal parasite infections were highly prevalent regardless of their diarrheal status. Opportunistic infections were reported. Improving the laboratory diagnosis of intestinal parasite infections and the knowledge on their local risk factors is warranted
Association of intestinal parasites with acute and persistent diarrhea in HIV-infected patients, Laos (n = 59).
<p><i>P</i>-value of Fisher exact test.</p><p>n.a., not applicable.</p
Demographic, clinical and laboratory characteristics of HIV-infected patients with regard to diarrhea, Laos (n = 137).
<p>OR, Odds Ratio.</p><p>CI, confidence interval.</p
Intestinal parasitic infections in HIV-infected patients by region of residence (Southern or Northern provinces), Laos (n = 137).
<p><i>P</i>-value of Fisher exact test.</p><p>n.a., not applicable.</p
Association of intestinal parasites with CD4 cell count in HIV-infected patients, Laos (n = 137).
<p>OR, Odds ratio.</p><p>CI, Confidence interval.</p