Thai Agricultural Research Journal

Phylogenetic Characterization of Fusarium oxysporum f.sp. cubense Complex Causing Banana Wilt Disease in Thailand

2025-07-29T17:47:12+07:00

Fusarium wilt in bananas, caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc), colonizes the vascular system, leading to severe wilting and plant death. This disease poses a critical threat to global banana production. In Thailand, Foc race 1 has long been present, whereas Foc tropical race 4 (TR4)—a devastating emerging pathogen affecting Cavendish bananas—has been detected through surveillance activities. Due to reports of Fusarium-like wilt symptoms of uncertain etiology, accurate identification is essential for establishing effective disease control measures. This research aimed to identify the species of Fusarium collected from symptomatic bananas across major cultivation areas in Thailand and also the Fusarium isolates collected from a pest control area, where eradication measures were implemented and which are currently no longer present in Thailand. The isolates of Fusarium have been preserved at the Department of Agriculture, which serves as the National Plant Protection Organization (NPPO) of Thailand under the International Plant Protection Convention (IPPC). The methodology involved fungal isolation, DNA extraction, PCR amplification, and nucleotide sequencing of the tef1 and rpb2 gene regions. The phylogenetic analyses were conducted for species identification. The results revealed significant genetic diversity among Foc race 1 isolates in Thailand, identifying them as F. tardichlamydosporum, F. duoseptatum, and F. grosmichelii. Additionally, F. kalimantanense was identified within the non-race group. Notably, the isolates from Cavendish bananas were identified as F. odoratissimum (syn. TR4), a pathogen currently classified as "not present" in Thailand. This study concludes that these species are phylogenetically closely related. Accurate identification within these species complexes requires molecular diagnostics to ensure precise differentiation and biosecurity management.

Kluai Namwa Variety DOA Sukhothai1

2025-05-21T19:35:12+07:00

Kluai Namwa variety DOA Sukhothai1 (Sukhothai55-4) has been improved by creating mutations through tissue culture. The regenerated plants were established in a germplasm collection and subsequently selected at the Sukhothai Horticultural Research Center for high yield potential. The selected line exhibits high yield potential, producing no fewer than seven hands per bunch. The fruits are characterized by firm pulp with white to pale yellow flesh, a sweet taste, and good eating quality, making this variety suitable for commercial production and consumption. After comparing the plant lines and testing the varieties at three locations: Sukhothai Horticultural Research Center, Loei Agricultural Research and Development Center, and Phetchaburi Agricultural Research and Development Center, which have different geographical conditions and climates. The results showed that the Kluai Namwa DOA Sukhothai1 produced the highest yield in all three locations, with an average bunch weight of 16.1 kg and 9.8 hands per bunch. The fruit is relatively round, with light cream-colored flesh, a fine-grained, and sweet flesh without sourness. Nutritional analysis of flesh fruit showed higher vitamin B3 and potassium contents than the Mali Ong. The variety was officially certified as a recommended variety by the Department of Agriculture on August 15, 2019, under the name Kluai Namwa variety DOA Sukhothai1, for distribution to farmers. Evaluation of farmer and entrepreneur acceptance indicated the highest level of satisfaction regading yield, income from sales, production costs, and processing potential. The quality traits including size and weight, fruit shape, starch content, ripe flesh color, and taste were also highly rated. This variety demonstrated strong potential for supporting local economic development though both fresh fruit marketing and value add processing.

Comparison of High-yield Industrial Pineapple Lines

2025-08-06T18:58:21+07:00

The pineapple processing industry used the Pattavia variety as a key raw material. Long use of this variety for cultivation has led to genetic variation, resulting in decreased yields. This research aims to compare high-yielding pineapple lines as alternatives to the Pattavia variety. A comparison trial of six hybrid lines and Pattavia was conducted at Phetchaburi Agricultural Research and Development Center from October 2017 to September 2020. Results showed that line PBI49-03-004 has a yield comparable to Pattavia, followed by line PBI49-07-045, which also has the same yield quality as Pattavia. Moreover, a comparison trial of eleven Pattavia clones and the Pattavia variety was conducted from October 2017 to September 2020 at Phetchaburi Agricultural Research and Development Center. The result showed that clones PBIC54-04-252, PBIC54-05-334, and PBIC54-05-544 had flowering induction exceeding 70% and a fruit/plant ratio higher than that of Pattavia. However, their yield and quality were comparable to Pattavia. From the results of two prior experiments, six pineapple lines, PBI49-03-004, PBI49-07-045, PBIC54-01-161, PBIC54-04-252, PBIC54-05-334, PBIC54-05-544, including Patavia, were selected and tested in production areas from October 2021 to September 2024 at Phetchaburi Agricultural Research and Development Center and Fairtrade Pineapple Growers’ Group in Prachuap Khiri Khan Province. Results showed that line PBIC54-04-252 produced an average yield of 11.53 t/rai, which was 30.58% higher than that of Pattavia (8.83 t/rai), with quality equivalent to Pattavia. Therefore, the PBIC54-04-252 line is suitable as a replacement for the Pattavia variety.

Combining Ability of Maize Inbred Lines under Water Stress Conditions

2025-05-08T12:16:00+07:00

Cultivating drought-tolerant maize is an effective strategy for reducing yield losses caused by dry spells during the growing season. The study aims to evaluate the combining ability of maize inbred lines under drought conditions to develop drought-tolerant hybrids with relatively high yields. The first experiment was conducted using a factorial mating design, producing 63 hybrids from 16 inbred lines (7 lines in Group 1 and 9 lines in Group 2). These hybrids were subsequently evaluated together with elite hybrid varieties and commercial varieties, totaling 70 varieties, with DOA Nakhon Sawan 5 used as the check variety. The test was performed under conditions of withholding water from before flowering for 2 weeks until reaching 1 month, then watering as usual. The second experiment was done using a 7 × 10 alpha lattice design with two replications during the 2024 dry season. The result showed that five hybrids, namely Nei502007 x Nei542006, Nei502007 x Nei542018, TF7 x Nei542020, Nei502007 x Nei532003, and TF7 x Nei542006, gave yields of 1,146, 1,046, 1,037, 1,034, and 1,026 kg/rai, respectively. These yields were higher than that of the check variety, DOA Nakhon Sawan 5 (749 kg/rai), but were not significantly different from those of the commercial hybrid DK7212C and CP389, which yielded 1,066 and 1,059 kg/rai, respectively. In addition, four inbred lines with high positive general combining ability and values significant difference from zero, Nei502007, Nei532003, Nei542006, and Nei542020, were selected as testers to evaluate yield potential for new hybrid development. These inbred lines will be used for development of drought-tolerant maize varieties in the future.

Responses of Rice Varieties to the Pathogenesis of Burkholderia glumae Collected from Different Regions of Thailand under Screenhouse Conditions

2025-06-16T16:59:56+07:00

The bacterial pathogen, Burkholderia glumae, can cause severe damage in rice in many countries. The B. glumae disease causes rotting seedlings, rotting leaf sheaths, rotting seeds, burning ears, and significant yield loss. The B. glumae has multiple isolates, each responding differently to each rice line/variety. Thus, the responses of different rice lines/varieties to the bacteria can be used to classify the bacterial groups. This study aims to assess the response of rice lines/varieties to the pathogenicity of B. glumae in greenhouse conditions. The samples of B. glumae were collected from rice fields in 41 districts in 10 provinces in the central, northern, and northeastern regions of Thailand. Thirty-eight isolates of B. glumae were found. Twenty-six isolates were selected and grouped according to their ability to cause disease in 20 rice lines/varieties. The inoculation procedure was done by injecting suspended B. glumae cells (1 x 10⁸ CFU/mL, O.D.₆₀₀ = 0.2) into leaf sheaths of the 45-day-old rice planted in greenhouses to assess their response to disease. The phylogenetic tree was also analyzed using the Bay-Curtis method to group the B. glumae. The results from the analysis can classify the B. glumae into a total of four groups. The B. glumae isolates from Buriram province are the most diverse and were classified into three groups, followed by the isolates from Phrae and Roi Et provinces, which were each classified into two groups.

Identification of Yanagi Mushroom (Cyclocybe spp.) Using Morphological Characteristics and ITS Region Sequences

2025-05-06T18:19:42+07:00

The Yanagi mushroom (Cyclocybe spp.) is one of the important mushrooms widely cultivated. Species identification of this mushroom in Thailand was confused. The objective of this research was to investigate morphological characteristics and identify ITS region sequences of Yanagi mushroom strains for correct identification. Nineteen strains of Yanagi mushrooms were collected from 10 different locations for the study. The results revealed that 18 strains showed brown or light brown to cream on the cap, cylindrical stalk, and off-white surface. After the cap was open, the partial veil was quite short seeming like C. cylindracea. While the Yanagi mushroom strain Ya11 was different, the cap color was brown to dark brown with tiny white scales, the stalk was cylindrical, the surface was light brown, and the partial veil was thicker and larger, seeming like
C. chaxingu. Furthermore, the nucleotide sequence analysis of the ITS region and phylogenetic analysis separated 19 Yanagi mushroom strains into two groups according to the morphological study. Thus, the identification of the Yanagi mushroom using both morphological characteristics and ITS region sequences was an accurate and efficacious method for use in the species identification of this mushroom in Thailand.

Biodegradable Laminated Paper from Cocoa Pod Husk for Bakery Containers

2025-07-04T13:01:11+07:00

Paper derived from cocoa pod husk generally exhibits limited mechanical durability. This research investigates the use of cocoa pod husk, a waste material, to produce disposable paperboard containers for bakery products. The chemical pulping process utilized sodium hydroxide-anthraquinone (SAQ) for pulping cocoa pod husks. The resulting cocoa pod husk pulp, referred to as SAQ5, displayed the best overall properties for paper production. The characteristics of the SAQ5 pulp included a yield of 77.87±2.57%, a kappa number of 26.0±0.1, a lignin content of 3.38±0.01%, and a freeness of 802.67±63.79 CSF. Subsequently, modified starch was added to the paper as a binding material. The paper produced, known as pulp 10 g and modified starch 0.25 g, exhibited the best overall properties for paper formation. The paper had an air permeability of 12.6±3.3 Pa·s/m, and a basis weight of 67.33±12.92 g/m². Laminating paper with polybutylene adipate-co-terephthalate (PBAT) film improved its resistance to water and oil. Among the samples tested, the paper laminate (PBAT 4-layer/paper/PBAT 4-layer) exhibited improved resistance to water and oil. It had a basis weight of 119.70±7.94 g/m² and a density of 1.40±0.20 g/cm³. When formed into containers for bakery products, such as sausage and mayonnaise-filled bread, butter cake, almond mixed butter cookies, and milk-flavored croissants, demonstrated resistance to fats and oils after 180 minutes.

Foliar Application of Calcium-Boron to Increase Production Efficiency and Reduce the Quality Loss of Irradiated ‘Nam Dok Mai Si Thong’ Mango

2025-07-03T19:53:42+07:00

Regarding plant quarantine measures, ‘Nam Dok Mai Si Thong’ mango exported to the United States, Australia, and New Zealand must be treated with gamma irradiation. The irradiation causes loss of quality in most mangoes at destination markets, with the symptoms of brown skin, watery flesh, and short shelf life. This research aimed to study treating mangoes with calcium-boron to increase production efficiency and to reduce loss of quality in irradiated mangoes. The appropriate concentration of calcium-boron for yield and quality improvement was also investigated. It was found that foliar spray of calcium-boron at a concentration of 0.5% at 30, 45 and 60 days after flowering produced the highest amount of yields and fruit quality. According to the effects of calcium-boron on irradiated mangoes, it was found that when they were stored under 13°C for 28 days for export simulation, irradiated mangoes receiving calcium-boron lost 22.45% of their quality. In contrast, irradiated mangoes without calcium-boron lost 60.34% of their quality. After that, treating calcium-boron technology was tested in mango planting plots for export, i.e., the community enterprise of quality mango production for export, Phetchabun, Nakhon Ratchasima, and Sa Kaeo Provinces. It was found that calcium-boron could increase production efficiency for farmers, with high yields up to 1,292 kg/rai, higher than the current method by 19.09% (16,569 baht/rai). This research revealed that treating mangoes with calcium-boron improved production efficiency and could reduce loss of quality in irradiated mango, and creates the opportunity for export markets to the countries using the plant quarantine measures by irradiation in the future.

Development of SNP Marker in Piezo-type Mechanosensitive Ion Channel Homolog (Piezo) Gene and Efficiency Testing of the SNP Marker in Screening for Heart Rot Disease Resistance in Pineapple

2025-05-20T23:18:29+07:00

Heart rot disease caused by fungi Phytophthora spp. is a major problem in pineapple production. This research was conducted to develop a primer set specific for a nonsynonymous SNP marker in the pineapple Piezo-type mechanosensitive ion channel homolog (Piezo) gene, S13_8307911, which exhibits nucleotide sequence differences between heart rot disease-resistant and susceptible varieties. PCR conditions were optimized to detect this SNP marker using tetra-primer ARMS–PCR technique. The efficiency of the SNP markers for selecting heart rot disease resistance was assessed in a hybrid pineapple sample set of 22 lines exhibiting resistance under natural conditions, using genotype–phenotype concordance as a measure of prediction accuracy. The results showed that SNP marker S13_8307911, compared with S6_3252739 in the E3 ubiquitin-protein ligase MED25 binding RING-H2 protein 1 gene and S15_644992 in the Pathogenesis-related protein-4-like gene, exhibited marker prediction accuracies of 95.5%, 100%, and 81.8%, respectively. These findings suggest that the identified SNP markers have potential for application in marker-assisted selection of pineapple varieties resistant to heart rot disease. However, further validation in larger and genetically diverse populations is necessary to confirm their stability and predictive performance before implementation in breeding programs.