The feasibility of using NIR reflectance spectroscopy to estimate the FA composition of sesame seed (Sesamum indicum L.) samples from the National Institute of Crop Science of Japan and from Myanmar was examined. Multiple linear-regression analyses of NIR spectral data and chemical data for whole seeds were carried out to develop calibration equations for predicting the proportion of each of the four major FA in sesame seeds from the total FA composition. The SE of prediction (SEP) was 0.616% for palmitic acid, 0.348% for stearic acid, 1.051% for oleic acid, and 0.826% for linoleic acid. This NIR method provides a simple, rapid, and nondestructive means of estimating the FA composition of sesame seeds for breeding selection, regardless of the color of the sesame seed coats. However, the proportions of palmitic and stearic acids could not be reliably measured because their SEP were almost as great as the SD of their concentrations in the set of prediction samples. The relationship between NIR spectral patterns and the FA composition of sesame seeds also was examined. The correlation coefficient calculated for the standardized second-derivative NIR spectral readings at 1708 nm and the percentages of linoleic acid was −0.830. A rough estimate of the proportion of linoleic acid in the total FA composition of sesame seeds could be obtained even with single sesame seeds, except for those with a black coat, based on NIR spectral pattern analysis using the wavelength assignments of linoleic acid.

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Native chickens in Myanmar and Thailand have been being domesticated for generations and yielded a wide variety of chickens. The objective of the research is to analyze the genetic variation and relationships of native chicken populations in Myanmar and Thailand. A total number of 249 genomic DNA samples from a total nine populations including the commercial lines, were genotyped using 98 autosomal SNP markers. The average heterozygosity of each population was in the range of 0.181-0.262. The neighbor-joining trees constructed by pair-wise F ST estimates corresponded that the native chickens in Myanmar and Thailand were at a distance from the commercial chickens. The STRUCTURE analysis revealed that the nine chicken populations used in this study might be derived from six genetic populations (K＝6). The AMOVA showed significant value of F ST with 79-90% of the total genetic variation found within populations. The F CT value was significant but accounted for only 4.45% of the total variability among countries. Finally, the mantel test for Isolation by Distance result (r＝0.5964; P＜0.01) suggested the contribution of geographic distance to the genetic structure of native chicken populations in Myanmar and Thailand.

The genetic diversity of native chicken populations from Myanmar, Thailand, and Laos was examined by using 102 insertion and/or deletion (indels) markers. Most of the indels loci were polymorphic (71% to 96%), and the genetic variability was similar in all populations. The average observed heterozygosities (HO) and expected heterozygosities (HE) ranged from 0.205 to 0.263 and 0.239 to 0.381, respectively. The coefficients of genetic differentiation (Gst) for all cumulated populations was 0.125, and the Thai native chickens showed higher Gst (0.088) than Myanmar (0.041) and Laotian (0.024) populations. The pairwise Fst distances ranged from 0.144 to 0.308 among populations. A neighbor-joining (NJ) tree, using Nei’s genetic distance, revealed that Thai and Laotian native chicken populations were genetically close, while Myanmar native chickens were distant from the others. The native chickens from these three countries were thought to be descended from three different origins (K = 3) from STRUCTURE analysis. Genetic admixture was observed in Thai and Laotian native chickens, while admixture was absent in Myanmar native chickens.