Vegetables In Thailand Research Articles

A Plant Growth Promoting of Rhizobacteria and Endophytic Bacteria in Vegetable Rhizosphere and Root Samples

Rhizobacteria and endophytic bacteria are popular for its abilities in influencing plant growth and development. The strategy employed these bacteria as biofertilizer for planting is believed to bring several benefits such as low cost, eco-friendly, and feasible. One of the remarkable products for plant growth promoting provided by rhizobacteria and endophytic bacteria were the advantageous enzymes such as 1-aminocyclopropane-1-carboxylate deaminase, phosphatase, and cellulase. These biocatalysts then involve in several direct or indirect pathways of nutrient, growth factor, and/or defense factor synthesizes. From five different essential leafy vegetables in Thailand, this study aimed to investigate the plant growth promoting potentials of endophytic bacteria and rhizobacteria isolated from root tissue and rhizosphere, respectively, via IAA quantitative and enzyme activity assays. The selected bacterial strains were further identified using 16S rRNA gene sequencing and observed their interaction with plant root using scanning electron microscope method. Our study, thus far, has isolated two bacterial strains of Bacillus subtilis MSE5 and Bacillus cereus AVR1, respectively, with multifunctional traits of potential on the plant growth. Importantly, these two strains of MSE5 and AVR1 had shown the capacity to advance root colonization. Therefore, MSE5 and AVR1 are recommended for further studies in developing eco-friendly biofertilizer. In addition, some novel cellulose-degrading bacterial strains with significant potential on hydrolysis capacity were also isolated that might be valuable for industrial applications.

A Performance of Marketing Information System for Fresh Vegetables in Thailand

A Performance of Marketing Information System for Fresh Vegetables in Thailand

Current Status and Breeding Perspectives of Major Vegetable Crops in Thailand

The climate of Thailand is appropriate for year-round production of vegetables whose domestic market share has continuously increased and production contributes significantly to the export. However, technology of vegetable breeding and cultivation is still in its early stage of development, compared to developed countries. Information on the major crops and their leading cultivars or varieties is prerequisite for establishing appropriate breeding strategies and developing cultivation technologies for vegetables. This article provides the current state of five major vegetables in Thailand such as chili (Capsicum annuum L. and C. frutescens L.), cabbage (Brassica oleracea L. var. capitata), shallot (Allium ascalonicum L.), yard long bean (Vigna sesquipedalis L.) and lettuce (Lactuca sativa L.), with their leading cultivars or varieties and traits that consumers in Thailand prefer. Breeding perspectives of these major vegetables in Thailand were also discussed.

Cypermethrin resistance in Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) from three locations in Thailand and detoxification enzyme activities

The tobacco cutworm Spodoptera litura is one of the key insect pests of vegetables in Thailand. This study evaluated cypermethrin resistance in populations of S. litura collected from vegetable crops in Bang Len and Kamphaeng Saen district, Nakhon Pathom province and from Wang Nam Khiao district, Nakhon Ratchasima province, Thailand. Resistance of S. litura was determined using the topical application method and biochemical assays, and all three field populations exhibited a trend of increasing resistance to cypermethrin compared to the susceptible laboratory population, with median lethal dose (LD50) values varying from 10.98 parts per million (ppm) to 15.74 ppm. The activities of cytochrome P450 monooxygenase and carboxylesterase in field populations of S. litura were significantly increased compared to those in susceptible insects, but glutathione S-transferase activity was significantly increased only in the Kamphaeng Saen population. These results indicated that the three field populations of S. litura had developed resistance to cypermethrin and it is suggested that continuous application of cypermethrin to control tobacco cutworm should be avoided to prevent the development of high cypermethrin resistance in this pest.

Reduce Loss during Transportation: A Case Study of Fresh Vegetables in Thailand

The cold chain management is the temperature control process which is essential for maintain the quality of fresh produce from upstream to the consumer in the supply chain so that the loss is minimized. Our objectives are to monitor the temperature during transportation, analyses and identify the problem cause loss of fresh vegetables by using causal-loop diagram. We monitor the temperature during transportation of fresh vegetables from a farm in Northern Thailand to a packing house in the central Thailand around 750 kms. for 17 to 18 hours. The fresh vegetables are packed in a stereo foam box with the cool packs and pile up on the back of a truck. At the packing house, fresh vegetables are bruised and rotten and loss about 30-40 percent by weight. The temperature is monitored by the data loggers. The result showed that the temperature inside the box during transport is 20oC-30oC where the range of external temperature is 20oC-40oC. Then, we suggest how to reduce loss by using proper management such as suitable material to control the temperature during transportation, location of box in the truck and packing method. Keywords: Cold Chain Management; Fresh Vegetable; Loss Reduction; Transportation

Development and Validation of LC-MS/MS Method for Quantitative Determination of Adenosine, Guanosine, Xanthine and Uric Acid in Widely Consumed Vegetables in Thailand

In this study, a triple quadrupole LC-MS/MS electrospray ionization method was developed and validated for quantitative determination of adenosine, guanosine, xanthine and uric acid in fifteen widely consumed Thai vegetables. The method was successively developed by using caffeine as internal standard. The lower limit of quantitation (LLOQ) was 0.2 μg/g for adenosine and guanosine, and 1.0 μg/g for uric acid and xanthine. The method was fully validated according to USFDA guidelines and all performance characteristics were found acceptable. Subsequently, the developed and validated LC-MS/MS method was applied to determine the four interest substances in fifteen widely consumed vegetables in Thailand. The results showed that all vegetables included in the study could be classified as low adenosine, guanosine, xanthine and uric acid containing foods since the concentrations of these substances were less than 50 mg per 100 g. This finding was enormously valuable information for hyperuricemia and gouty patients.

Development and Validation of an UV-Visible Method for the Determination of β-Carotene in the Leafy Vegetables in Thailand

Determination of β-carotene content in four types of leafy vegetables, water morning glory, kale, lettuce and Chinese cabbage by using a simple, rapid and low cost of UV-Visible method. This study was in the concentration range of 0.5 to 12 mg/L, and showed the linear regression equation y = 0.0764x - 0.0008, and an excellent linearity with correlation coefficient (R2) was 0.9999. The accuracy of the method analysis was reported by percentage recovery of about 80-106%. The precision was reported by percent of relative standard deviation and varies for intra-day 3.92% and inter-day 3.99%. The limits of detection and limit of quantification were 0.004 and 0.013 mg/L, respectively. Acetone is the most suitable for extraction, ratio of weight of samples to solvent, and extraction time was 1:3 g/mL and 10 min. Moreover, the most appropriate storage temperature for leafy vegetable samples is 4°C. Evaluation of β-carotene content under the suitable conditions in the kale, Chinese cabbage, lettuce and water morning glory was found to be 27.96 ± 2.99, 19.35 ± 1.92, 18.78 ± 0.88 and 18.48 ± 1.86 mg/100 g, respectively.

Adoption of Improved Varieties of Vegetable Crops with Pesticide Use in Chiang Mai Province, Northern Thailand

The increasing urban demand for vegetables in Thailand has been met through peri-urban areas in the central plains, northern valleys and highland rural areas. Use of modern technology like improved varieties, fertilizer, pesticides, growth hormones, and modern cultivation practices is the common feature of commercial vegetable production in recent periods. Improved varieties of the vegetable crops are considered as the important bio-innovation that affects the livelihood and health aspects of the farmers.This study focused on various aspects related to the adoption of improved or hybrid varieties of vegetable crops in northern Thailand. We analysed the effects of hybrid varieties on household income, self-employment and human health aspect. In addition, we studied about farmers’ opinions of pesticide using in group of pesticide and non- pesticide use and expressed the gender role in different vegetable production activities.The paper is based on the study of commercial vegetable production areas around Chiang Mai city, which is covering two research sites: Mae Wang and Saraphi. Mae Wang is one of the rapidly transforming areas in Chiang Mai valley that provide the situation of fast growing commercial vegetable cultivation mostly in rural settings. Saraphi is the adjoining district to the Chiang Mai city that represents peri-urban commercial vegetable production both conventional as well as pesticide free vegetable production areas.Farmers are getting higher household income from the adoption of improved or hybrid varieties of the vegetable crops. In many cases local farmers have been able to embrace vegetable cultivation as self-employment opportunity as well. Since people are well aware about the negative effects of excessive chemical use in the commercial production, the production of vegetable without pesticide use is on rise in the selected study areas. But, interestingly, the farm-gate and market price was almost similar with or without pesticide use vegetable. However, the non-pesticide farmers confirmed that they still choose to produce the vegetables without pesticide because they believe they save money from the medical payment due to agrichemical poisoning, which generate higher income over all.There is not much difference in involvement of women and men farmers in different production activities. However, less women farmers are less motivated to promote their products to the market by marketing since they believe it would only increase their work, but the outcome from the promotion is low.Another crucial aspect in promotion of commercial production is the proper marketing management. Production areas near the Chiang Mai city are in relatively better situation for getting proper market and price for their produce. But the irony is that organic vegetable producers, despite working in groups, are not involved in organized marketing efforts and thus not been able to tap the market demand and better price for their pesticide free production.

Effect of Amount of Nitrogen Fertilizer on Early Growth of Leafy Vegetables in Thailand

Effect of Amount of Nitrogen Fertilizer on Early Growth of Leafy Vegetables in Thailand

A Study of Marketing Information and Communication for Fresh Vegetable in Thailand

This study is dealt with the marketing information in role and provision in marketing information service. Including, identify marketing information needs for fresh vegetable market which brings about development of fresh vegetable marketing information and communication in Thailand. The results were as follows. 1) The role of marketing information for vegetables in Thailand was designed to: ①provide local producers and traders information on wholesale and retail prices of vegetable on a regular basis; ②provide producers information on annual price trends of farm commodities for better production scheduling; ③assist producers in deciding where, when, how much, to whom and in what price to sell their current produce in order to lessen marketing risk; ④improve the bargaining position of producers; and ⑤help institutional buyer keep updated prices as bases for their procurements. 2) Vegetable marketing information is provided by Department of Internal Trade and Office of Agricultural Economics. They collects weekly and monthly data which are farm gate price and average market price and distributes them to market members. They will then provide price information to producers, traders, and consumers as a major service item. Reports are issued on a daily, weekly, monthly, and annual basis. The marketing information flash through the communication techniques by extension workers from Agricultural Extension Office, and main public media releases such as radio, television, and newspaper, as well as through government printed reports. 3) The marketing information needs of various stakeholders consist of: ①information on markets according to season and area; ②quality demands, efficient production, storage, processing methods; ③prices along the chain; ④Lists of buyers; ⑤market regulations and policies; ⑥meetings and workshops; ⑦size and location of sources of raw materials

Consumer perceptions of organic foods in Bangkok, Thailand

In response to food scares related to high levels of pesticide residues sometimes found on vegetables and fruits, consumers in Thailand increasingly demand ‘safe’ foods. This has resulted in a number of initiatives and labels indicating ‘pesticide safe’ vegetables. However, the pesticide-residue problem has proved enduring. This opens a market opportunity for organic foods, which are produced entirely without using synthetic chemicals. As little is known on consumer perception of organic foods in Thailand, a survey was conducted in Bangkok. More than a third of the 848 respondents reported having purchased organic vegetables or fruits in the past. The main reasons for purchasing organic products are that consumers expect them to be healthier, that organic products are environmentally friendly. The respondents who have bought organic vegetables tend to be older, have a higher education level and a higher family income than those who have not bought them. The main barrier to increasing the market share of organic vegetables is that consumers do not clearly differentiate between the various ‘pesticide safe’ labels and the organic labels. Informing consumers about unique characteristics of organic production methods, the strict inspection and required third party certification might be a promising strategy to develop the market for organic vegetables in Thailand’s urban centers.

DETECTION AND CLASSIFICATION OF SOFT ROT ERWINIA OF VEGETABLES IN THAILAND BY DNA POLYMERASE CHAIN REACTION

Detection and classification of soft rot Erwinia of vegetables in Thailand were conducted from ten varieties of vegetables; cauliflower, cabbage, chinese cabbage, pak-choi, spinach, carrot, chinese radish, cucumber, tomato and asparagus. To determine soft rot Erwinia, soft rot bacteria were isolated from rot symptom of these vegetables on pectate assay medium and identified by technique of DNA polymerase chain reaction. Using Y1 and Y2 primers are specific to amplify 434 bp open reading frames of pectate lyase (pel) genes of E. carotovora while ADE1 and ADE2 primers are specific to amplify 420 bp open reading frames of pectate lyase genes of E. chrysanthemi. The result showed that only Y1 and Y2 primers were able to amplify genomic DNA of all isolates. [...]

Biological Control of Crucifer Crop Pests and Participatory IPM in Thailand

Larvae of the diamondback moth (DBM), Plutella xylostella L. (Lepidoptera: Ypeunomutidae) and other crucifer pests cause severe economic damage to cabbage, Brassica oleracea L. var. capitata (Brassicaceae) and related vegetables in Thailand and elsewhere in Southeast Asia. Overuse of pesticides is a serious problem in most vegetable growing areas of the country. Six species of parasitoids were reared from DBM larvae and pupae collected in northern Thailand in 1989–90 and 2003–04. The larval parasitoid Cotesiaplutellae Kurdjumov (Braconidae) appears to be the most important parasitoid of DBM in Thailand; other native or naturalized parasitoids may play supplementary roles. These natural enemies can and should be conserved in well thought out, participatory IPM programs. Field experiments comparing local farmer practice (weekly sprays of synthetic pyrethroid insecticides) to a simple IPM protocol using Bt and neem demonstrated superior control and higher yields of undamaged cabbage from the IPM treatment. This information on DBM parasitoids and other natural enemies of crucifer pests has been developed into a poster and other extension materials currently used in national “training of trainer” (for vegetable IPM) programs throughout Thailand. Farmer-centered IPM programs focused on conservation of local DBM parasitoids and on greater implementation of biological control will help alleviate growing public concerns regarding the effects of pesticides on vegetable growers and consumers.

Hymenopteran Parasitoids of Diamondback Moth (Lepidoptera: Ypeunomutidae) in Northern Thailand

Larvae of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Ypeunomutidae), cause severe economic damage to cabbage, Brassica oleracea L. variety capitata (Brassicaceae) and related vegetables in Thailand. Overuse of broad-spectrum insecticides for diamondback moth control is a serious problem and has obscured the contributions of indigenous parasitoids. Our objectives were to identify indigenous diamondback moth parasitoids in northern Thailand and to assess their potential for natural control. Six parasitoid species were reared from diamondback moth larvae and pupae collected in 1990 and in 2003-2004. These included the larval parasitoid Cotesia plutellae Kurdjumov (Braconidae), a larval-pupal parasitoid Macromalon orientale Kerrich (Ichneumonidae), and pupal parasitoids Diadromus collaris Gravenhorst (Ichneumonidae) and Brachymeria excarinata Gahan (Chalcididae). Single specimens of Isotima sp. Forster (Ichneumonidae) and Brachymeria lasus Walker (Chalcididae) also were reared from diamondback moth hosts. C. plutellae was the dominant larval parasitoid and was often reared from host larvae collected from fields sprayed regularly with insecticides; parasitism ranged from 14 to 78%. Average parasitism by M. orientale was only 0.5-6%. Parasitism of host pupae by D. collaris ranged from 9 to 31%, whereas B. excarinata pupal parasitism ranged from 9 to 25%. An integrated pest management (IPM) protocol using simple presence-absence sampling for lepidopterous larvae and the exclusive use of Bacillus thuringiensis (Bt) or neem resulted in the highest yields of undamaged cabbage compared with a control or weekly sprays of cypermethrin (local farmer practice). IPM programs focused on conservation of local diamondback moth parasitoids and on greater implementation of biological control will help alleviate growing public concerns regarding the effects of pesticides on vegetable growers and consumers.

Hymenopteran Parasitoids of Diamondback Moth (Lepidoptera: Ypeunomutidae) in Northern Thailand

Larvae of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Ypeunomutidae), cause severe economic damage to cabbage, Brassica oleracea L. variety capitata (Brassicaceae) and related vegetables in Thailand. Overuse of broad-spectrum insecticides for diamondback moth control is a serious problem and has obscured the contributions of indigenous parasitoids. Our objectives were to identify indigenous diamondback moth parasitoids in northern Thailand and to assess their potential for natural control. Six parasitoid species were reared from diamondback moth larvae and pupae collected in 1990 and in 2003–2004. These included the larval parasitoid Cotesia plutellae Kurdjumov (Braconidae), a larval-pupal parasitoid Macromalon orientale Kerrich (Ichneumonidae), and pupal parasitoids Diadromus collaris Gravenhorst (Ichneumonidae) and Brachymeria excarinata Gahan (Chalcididae). Single specimens of Isotima sp. Förster (Ichneumonidae) and Brachymeria lasus Walker (Chalcididae) also were reared from diamondback moth hosts. C. plutellae was the dominant larval parasitoid and was often reared from host larvae collected from fields sprayed regularly with insecticides; parasitism ranged from 14 to 78%. Average parasitism by M. orientale was only 0.5–6%. Parasitism of host pupae by D. collaris ranged from 9 to 31%, whereas B. excarinata pupal parasitism ranged from 9 to 25%. An integrated pest management (IPM) protocol using simple presence-absence sampling for lepidopterous larvae and the exclusive use of Bacillus thuringiensis (Bt) or neem resulted in the highest yields of undamaged cabbage compared with a control or weekly sprays of cypermethrin (local farmer practice). IPM programs focused on conservation of local diamondback moth parasitoids and on greater implementation of biological control will help alleviate growing public concerns regarding the effects of pesticides on vegetable growers and consumers.