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Alopecia and gray hair are common hair abnormalities affecting physical appearance and causing psychological problems. Chemical treatments partially restore hair disorders but have distressing side effects. Bioactive plant compounds constitute promising sources of potential medicinal substances instead of chemical agents, producing high side effects. In this study, we focused on the waste of local rice cultivars: Bue Bang 3 CMU (BB3CMU) and Bue Bang 4 CMU (BB4CMU) from the north of Thailand. The rice bran oil (RBO), defatted rice bran extract (DFRB), and rice husk (H) were determined for in vitro hair revitalization in melanin production, nitric oxide (NO) secretion, and steroid 5α-reductase inhibition. The results indicated that BB4CMU-RBO with high contents of iron, zinc, and free fatty acids showed a comparable induction of melanin production on melanocytes (130.18 ± 9.13% of control) to the standard drug theophylline with no significant difference (p > 0.05). This promising melanin induction could be related to activating the NO secretion pathway, with the NO secretion level at 1.43 ± 0.05 µM. In addition, BB4CMU-RBO illustrated a significant inhibitory effect on both steroid 5α-reductase genes (SRD5A) type 1 and type 2, which relates to its primary source of tocopherols. Hence, rice bran oil from the Thai rice variety BB4CMU could be applied as a promising hair revitalizing candidate, from natural resources, to help promote hair growth and re-pigmentation effects. [ABSTRACT FROM AUTHOR]

This study evaluated the variation in bioactive compounds (anthocyanins, phenols, and antioxidants) among 22 rice varieties in the same growing locations and among four varieties collected from eight different provinces in Northern Thailand. Wide variation in anthocyanins, phenols, and antioxidant capacity was established, ranging from 1.6 to 33.0 mg/100 g, 249.9 to 477.7 mg gallic acid/100 g, and 0 to 3,288.5 mg trolox equivalent/100 g, respectively. The highest straw anthocyanin and phenol concentrations were found in KDK (a traditional photoperiod-sensitive variety with purple pericarp and leaves) and K4 (an advanced, photoperiod-insensitive variety with purple pericarp and leaves), while the highest antioxidant capacity was found in KH CMU (an improved traditional photoperiod sensitive variety with a purple pericarp and green leaves) and K4. The variation of the bioactive compounds was also found in the same variety grown at different locations, e.g., the KDMl105 grown in Prayao province had a straw anthocyanin concentration higher than when grown in Mae Hong Son province. The effect was also observed in phenol content and antioxidant capacity when the same rice variety was grown across various locations. A significant correlation between total phenol and antioxidant capacity was observed across rice varieties and growing locations but was not found between anthocyanin and antioxidant capacity. This study found that the bioactive compounds in rice straw varied among rice varieties and growing locations. Straw phenol acts as a major antioxidant that can be used as a characteristic for the selection of rice varieties with high antioxidant capacity for use at the industrial scale for the processing of food, pharmaceuticals, and medicinal products. [ABSTRACT FROM AUTHOR]

Heat stress, a regular risk to wheat in the subtropics, is a growing threat in other wheat producing regions as the global temperature rises. This paper reports on three experiments evaluating 49 entries of the 13th High Temperature Wheat Yield Trial (13HTWYT) from the International Centre for Maize and Wheat Improvement (distributed in 2014), with Fang 60 as the local check, at two locations at Chiang Mai, Thailand, a designated representative of the wheat mega-environment 5, in which temperature for the coolest month averages >17.5 °C and the crop is subjected to high temperature for the entire growing season. The wheat was grown in the lowland (elevation 330 m) at Chiang Mai University in (i) sand culture to simulate the condition of non-limiting nutrient and water supply and (ii) in the field and (iii) as an on-farm trial in the highlands (elevation 800 m) at Mae Wang district of Chiang Mai province. Heat tolerance in the wheat germplasm, recently developed for adaptation to high temperature, was indicated by longer pre-heading duration, and the positive correlation between days to heading and grain yield all three experiments. The longer time before heading enabled development of larger spikes that produced more seeds from more and larger spikelets and more competent florets. However, with the number of spikes that was either lower than or similar to Fang 60, none of the recently developed 13HTWYT entries out-yielded the local check from the 1970s. [ABSTRACT FROM AUTHOR]

Purple or black rice (Oryza sativa L.) is a culturally important germplasm in Asia with a long history of cultivation in northern Thailand. Purple rice is identified by the color of the rice pericarp, which varies from purple to black with the accumulation of phenolic acids, flavonoids, and anthocyanins. In the present study, we assessed molecular variation within and between wetland purple rice landraces germplasm from northern and northeastern Thailand using 12 microsatellite loci. All purple rice varieties surveyed showed high levels of homozygosity within varieties and strong genetic differentiation among varieties, indicating the fixation of genetic differences among them. This pattern is consistent with purple rice farming practices in northern Thailand, where a small portion of harvested seed is selected and replanted based on farmers' preferences. The reduced genetic diversity and high homozygosity observed for purple rice is also consistent with patterns expected for this inbreeding crop. Genetic differentiation among the varieties showed some degree of structuring based on their geographical origin. Taken together, these data highlight that the genetic diversity and structure of wetland purple rice landraces is shaped by farmer utilization and cultivation through local cultural practices, and that conservation should focus on ex situ conservation across its cultivation range, along with on-farm, in situ conservation based on farmers' seed-saving practices. In situ conservation may prove especially valuable for preserving the genetic identity of local varieties and promote adaptation to local environments. [ABSTRACT FROM AUTHOR]

Sprangletop ( Leptochloa chinensis L. Nees) is a serious grass weed in direct-seeded rice cropping systems in Thailand. One population of sprangletop, BLC1, was found to be resistant to fenoxaprop-p-ethyl at 62-fold the concentration of a susceptible biotype, SLC1. This study elucidated the inheritance of resistance to fenoxaprop-p-ethyl in this sprangletop BLC1 genotype. The reaction to the herbicide at 0.12-2.4 mg ai L−1 was determined in the seedlings of self-pollinated resistant BLC1, susceptible SLC1 and SLC1 that had been allowed to cross-pollinate with BLC1. At 0.24 mg ai L−1, all the seedlings of SLC1 were killed, while 99% of BLC1 survived, along with 5% of the cross-pollinated SLC1 seedlings, which were considered to be putative F1 hybrids. The root and shoot lengths of the F1 hybrids in 0.24 mg ai L−1 of fenoxaprop-p-ethyl, relative to those in the absence of the herbicide, were close to or the same as the resistant parent, indicating that the resistance is a nearly complete to complete dominant trait. One-hundred-and-forty-one of the F2-derived F3 families were classified by their response to the herbicide at 0.24 and 0.48 mg ai L−1 into 39 homozygous susceptible : 72 segregating : 30 homozygous resistant, fitted with a 1:2:1 ratio at χ2 = 1.21 and P = 0.56, indicating that the resistance to fenoxaprop-p-ethyl in the sprangletop BLC1 genotype is controlled by a single gene. [ABSTRACT FROM AUTHOR]

Androgenetic alopecia (AGA), a hair loss disorder, is a genetic predisposition to sensitive androgens, inflammation, and oxidative stress. Unfortunately, current treatments with synthetic medicines contain a restricted mechanism along with side effects, whereas the bioactive constituents of plant extracts are multifunctional, with fewer side effects. The massive amounts of rice husk and bran are agricultural wastes that may cause pollution and environmental problems. Owing to these rationales, the local rice variety, Bue Bang 3 CMU (BB3CMU), which is grown in northern Thailand, was evaluated for the valuable utilization of rice by-products, husk (BB3CMU-H) and bran (BB3CMU-RB) extracts, for AGA treatment regarding antioxidant, anti-inflammatory, anti-androgenic activities, and the characterization of bioactive compounds. Our study verified that BB3CMU-H had the highest level of polyphenols, contributing to its greater antioxidant activity. Conversely, BB3CMU-RB was the predominant source of tocopherols, resulting in better anti-androgenic activities regarding the downregulation of steroid 5α-reductase genes (SRD5A). Notably, anti-inflammation via the attenuation of nitric oxide productions was observed in BB3CMU-H (0.06 ± 0.13 μM) and BB3CMU-RB (0.13 ± 0.01 μM), which were significantly comparable to diclofenac sodium salt (0.13 ± 0.19 μM). Therefore, the combination of BB3CMU-H and BB3CMU-RB could be utilized in cosmeceutical and pharmaceutical applications for AGA patients. [ABSTRACT FROM AUTHOR]

Rice is among the 3 most important crops worldwide. While much of the world's rice harvest is based on modern high-yield varieties, traditional varieties of rice grown by indigenous groups have great importance as a resource for future crop improvement. These local landraces represent an intermediate stage of domestication between a wild ancestor and modern varieties and they serve as reservoirs of genetic variation. Such genetic variation is influenced both by natural processes such as selection and drift, and by the agriculture practices of local farmers. How these processes interact to shape and change the population genetics of landrace rice is unknown. Here, we determine the population genetic structure of a single variety of landrace rice, Bue Chomee, cultivated by Karen people of Thailand. Microsatellite markers reveal high level of genetic variation despite predominant inbreeding in the crop. Bue Chomee rice shows slight but significant genetic differentiation among Karen villages. Moreover, genetically determined traits such as flowering time can vary significantly among villages. An unanticipated result was the overall pattern of genetic differentiation across villages which conforms to an isolation by distance model of differentiation. Isolation by distance is observed in natural plant species where the likelihood of gene flow is inversely related to distance. In Karen rice, gene flow is the result of farmers' seed sharing networks. Taken together, these data suggest that landrace rice is a dynamic genetic system that responds to evolutionary forces, both natural and those imposed by humans. [ABSTRACT FROM AUTHOR]

This experiment examined variation of iron (Fe) concentration in grain of local Thai rice varieties from Huai Tee Cha village, in northern Thailand. Seeds of 17 named varieties were collected from farmers in 66 accessions. Brown rice from each accession was stained individually with Perls’ Prussian blue, with IR68144 (high grain Fe) and KDML105 (low grain Fe) as checks. A wide range of grain Fe contents were found among different varieties, different seed lots with the same name and within individual accessions, notably BB, BGU and BK. The Fe concentrations in these varieties were confirmed by chemical analysis. Two accessions of each variety with most intense staining and highest average concentration of grain Fe were selected, and 20–40 seeds from each were sown for subsequent progeny testing. There was morphological variation between plants in 5 out of 6 accessions in characteristics such as pigmentation of the apiculus, pericarp and seed coat, while the sixth was externally uniform. Analysis for Fe concentration in seeds of individual lines found that the highest Fe lines were 40% to 50% higher than the lowest Fe lines. This range of grain Fe was found in all six accessions that were progeny tested, including BGU5 which was externally uniform in appearance ( H′ = 0). We have shown that variation in grain Fe concentration in local Thai rice may be found between different seed lots bearing the same name and within individual seed lot as well as between varieties. This level of genetic variation may need to be considered when assessing for traits such as grain Fe for breeding programs. [ABSTRACT FROM AUTHOR]

Purple rice is a functional food with health benefits and industrial potentials. In northern Thailand, purple rice landraces are grown either as wetland or upland rice, in the lowlands and highlands, in small amounts along with the staple rice. This study examined diversity of 37 accessions of purple rice collected from farmers with InDel cytoplasm markers for subspecies differentiation, 16 SSRs markers for within and between accessions variation, and selected grain quality features, namely, anthocyanin, iron, zinc, and gamma oryzanol content, when grown together as wetland rice. Most of the purple rice, originally grown as upland rice in both the lowlands and highlands, were identified as tropical japonica, except the wetland accessions from the lowlands that almost all belonged to the indica group. A high degree of genetic differentiation was found between the upland and wetland ecotypes, but none between those from the lowlands and highlands. A highland origin of the purple upland rice populations in the lowlands, possibly with adaptation to the upland rice cultivation of the tropical japonica, is suggested by the close genetic affinity between the highland and lowland populations of the upland ecotype. Grown in a much smaller area than the staple unpigmented rice, purple rice landraces are also less diverse genetically. Identification of purple rice landrace populations with exceptional anthocyanin and gamma oryzanol contents demonstrates that purple rice landraces can be a source of agronomically useful traits, while being an important cultural heritage, and contributing to the genetic diversity of the local rice germplasm. [ABSTRACT FROM AUTHOR]

Fragrance, which plays an important role in determining the economic value of rice to growers and consumers, is known to be controlled by the Badh2 gene. This study evaluated the grain quality characteristics and allelic variation of the Badh2 gene in 22 fragrant rice landraces from Thailand. The rice seed samples from farmers' storage facilities in northern, northeastern and southern Thailand, plus two advanced breeding lines and three check varieties, were evaluated for seed morphology and grain quality, and their Badh2 genes covering intron 4 to intron 8 were re-sequenced. Almost all of the landraces were classified as large grain types, with medium to high gelatinization temperatures. The variation in the Badh2 gene by haplotype analysis correlated with grain aroma by sensory evaluation. The badh2-E7 was found in haplotype 1 with a strong aroma in KH, NDLP, and PLD, as in KDML105 and the moderately aromatic BNM-CMU, BNM4, and SKH, along with PTT1. Three haplotypes had different positions of SNP on the Badh2 gene with varying results in the sensory test. The present results suggest that some rice varieties could be potentially introduced as genetic resources for fragrant rice breeding programs or could be developed to highly palatable cultivars with geographical indications to increase the income of highland farmers. [ABSTRACT FROM AUTHOR]