Journal of Agricultural Research and Communications

Optimization of Cellulose Production from Orange Pomace by Acetobacter xylinum

Supavej Maniyom, Sathian Boonkum, Siriwat Jinsiriwanit, Patcharee Pattanagul — Tue, 30 Sep 2025 00:00:00 +0700

The objectives of this study were to determine the optimum concentration of mannitol (3 - 7%) and yeast extract (0.3 - 0.7%) as well as the optimum shaking rate (0, 50, 100 and 150 rpm) for cellulose production from orange pomace by Acetobacter xylinum and to examine other qualities of bacterial cellulose and marinade. It was found that the cultivation of A. xylinum on medium made from orange pomace supplemented with 3 % mannitol and 0.66% yeast extract gave the highest cellulose yield of 25.31 g (from 30 g of orange pomace). The addition of different amounts of mannitol and yeast extract affected the changes in color values, L*, a*, b* and moisture content of cellulose sheets, as well as reducing sugar content, soluble solids and acetic acid content of the marinade. While the optimum shaking rate was 100 rpm, the maximum cellulose yield was 42.82 g and the maximum acetic acid concentration in the marinade was found to be 2.93 g/L at the shaking rate of 50 rpm.

Diagnosis of Candidatus Liberibacter solanacearum Associated with Imported Seed Potatoes

Tue, 30 Sep 2025 00:00:00 +0700

Zebra chip disease in potatoes is caused by the bacterium Candidatus Liberibacter solanacearum, poses a serious threat to potato production in Thailand. Although the disease has not yet been reported in the country, outbreaks have occurred in seed potato-exporting countries. Therefore, interception and preventive measures are essential to prevent the introduction of this pathogen and its potential damage on the domestic potato industry. In this study, a total of 134 imported seed potato samples from six countries — Australia, Canada, the Netherlands, New Zealand, Scotland, and the United States — were examined during 2021–2023. Diagnosis was conducted using accurate and rapid molecular techniques (nested-PCR) in combined with visual inspection for zebra chip symptoms on seed tubers. In addition, field surveys were conducted in potato-growing areas of several provinces in Thailand, including Chiang Rai, Chiang Mai, Tak, Phayao, Sakon Nakhon, and Nakhon Phanom. The results revealed no detection of either Ca. L. solanacearum or zebra chip symptoms in imported seed potatoes samples or in field surveys. These findings provide an important reference for establishing import regulations for seed potatoes, and contribute to the prevention and control the potential introduction and spread of this destructive pathogen in Thailand.

Evaluation of Quick Assessment Method for Mechanical Damage in Soybean Seed

Papassorn Wattanakulpakin, Kantima Thongsri , Paveena Ruk-Ak — Tue, 30 Sep 2025 00:00:00 +0700

Mechanical damage plays an important role in seed quality. According to high protein and oil components, soybean seed becomes fragile during harvesting and processing, resulting in reduced seed yield and quality. Mechanical damage to the seed is monitored after threshing and processing to reduce loss of quantity and quality. Although the Indoxyl acetate (IDA) test is recommended for mechanical soybean seed damage detection, it is complicated, expensive, and difficult to apply in the field. Therefore, quick assays were conducted on 15 soybean (cv. DOA Chiangmai 60) seed lots to detect mechanical damage to soybean seed, namely fast green (FG), ferric chloride (FC), and sodium hypochlorite (SDH), and the results were then compared with the IDA method. The germination and vigor—as measured by accelerated aging tests—ranged from 71% to 90% and 46% to 86%, respectively. The average mechanical damage to 15 seed lots tested by IDA equated to 7.9%, significantly different from FG (11.3%), FC (11.2%), and SDH (11.6%) methods determined by the paired t-test. The correlation coefficient (r) and linear regression (R²) among mechanical damage methods were analyzed, with the greatest significance found between IDA and SDH. Although the mechanical damage determined by SDH was significantly higher than IDA, this method revealed the closest relationship with IDA and exhibited the moderate negative correlation with germination, as well as being the easiest, cheapest, and most feasible for soybean seed cv. DOA Chiangmai 60 application in the field compared to other methods.

Development and Increasing Efficiency of Highland Rice Production by Ready-to-use Technology in Pang Mapha District, Mae Hong Son Province

Taparat Seeloy-ounkaew, Sarayoot Wongkum, Sangtiwa Suriyong, Suttakarn Jaikawin — Tue, 30 Sep 2025 00:00:00 +0700

The objective of this research was to develop and improve the efficiency of highland rice production using ready - to - use technology in Pang Mapha District, Mae Hong Son Province. The experiment compared the Rice Department’s technology package, managed by researchers, with farmer’s practices. Treatments were conducted in both lowland and upland rice ecosystems across six plots with two replications. The soils were classified as clay and sandy clay loam, with pH ranging from slightly acidic to very strongly acidic, and organic matter levels from medium to high. Comparison of fertilizer management methods showed that plots managed by researchers produced higher rice yields than those managed. Differences in tiller number and plant height were observed between upland and lowland ecosystems. Rice yields in the technology verification plots ranged from 372.2 to 492.5 kg/rai, with yield components including 1,000 - grain weight of 31.5 - 38.8 g and panicle length of 25.7 - 30.8 cm. In contrast, yields from farmer-managed plots ranged from 276.0 to 460.8 kg/rai, with 1,000 - grain weight of 29.8 - 37.0 g and panicle length of 25.3 - 29.6 cm. Notably, the rice variety Bua Mae Cha Tha, transplanted in all demonstration plots, produced higher yields than farmer fields. In Ban Mueang Pham (T1), panicle number was 220 panicles/m², lowland than in T2 (259 panicles/m²), but T2 still produced the highest yield (674 kg/rai) due to its longer panicles (about 3 cm longer). Therefore, increasing the efficiency of rice production in this area requires site-specific technological approaches tailored to each ecosystem to achieve maximum rice yield

Weed Seed Contamination in Imported Celery Seeds

Tue, 30 Sep 2025 00:00:00 +0700

In 2022-2023, a total of 83,532.4 kilograms of celery (Apium graveolens) seeds were imported into Thailand from the United States (29,647.2 kg), Mexico (28,897.5 kg), Italy (24,986 kg), France (1.2 kg) and China (0.5 kg). Twenty-seven consignments of celery seeds were randomly sampled according to the International Seed Testing Association (ISTA) standards and examined in the laboratory for weed seed contamination, followed by germination testing. Weed seeds of Polygonum bellardii were detected in four samples from the United States. Five weed species were detected in six samples from Mexico: Amaranthus viridis, Chenopodium murale, Echinochloa colona, Melilotus indicus and P. bellardii. Three weed species were found in fifteen samples from Italy: Helminthotheca echioides, C. album and Solanum ptychanthum. One sample from France contained P. bellardii, while no weed seeds was detected in sample from China. Among these, C. album is listed as a quarantine pest of Thailand, while C. murale, S. ptychanthum and H. echioides have not been previously reported in the country. Pest risk analyses may therefore be required to determine appropriate handling measures. All detected weed seeds were able to germinate under testing conditions. Field inspection in Tak and Chiang Mai provinces did not detect any quarantine pests.