Effects of Thickness Fraction Process on Physicochemical Properties, Cooking Qualities, and Sensory Characteristics of Long-Grain Rice Samples

A process of removing thinner kernels of rough rice, i.e., thickness fraction process, has been suggested as a method for increasing milling yields in the rice industry. This study aimed at determining whether physicochemical properties, cooking qualities, and sensory characteristics of rice samples could be changed by the addition of a thickness fraction into the rice process stream. Each of four long-grain rice cultivar lots was assigned into two groups: unfractionated and thickness-fractionated. For the thickness-fractionated group, thin rice kernels (<1.9 mm) of rough rice were discarded from unfractionated rice samples. Unfractionated and thickness-fractionated rice samples were compared with respect to physicochemical properties, cooking qualities, and sensory characteristics. The results showed that the removal of such thin kernels decreased the breakage and chalkiness rates and increased head rice yields. Fractionated rice samples exhibited lower amylose contents and crude protein contents but higher gelatinization temperatures than unfractionated rice samples. While the optimum cooking duration and width–expansion ratios of thickness-fractionated rice samples were higher than those of unfractionated ones, there was a negligible impact of the thickness fraction process on sensory characteristics of long-grain rice samples. In conclusion, the thickness fraction process affects physicochemical properties and cooking qualities more than the sensory characteristics of rice samples.

Determination of perchlorate and its distribution in unhusked rice in China

Perchlorate concentrations in 387 unhusked rice samples from 15 main producing provinces in China were investigated by HPLC–MS/MS. The results indicated that perchlorate displays a mean level of 17.17 μg/kg in unhusked rice samples. Intriguingly, we also found that perchlorate is mainly observed in rice husk among of these collected unhusked rice samples, while less observed in rice bran and milled rice. Specifically, the perchlorate levels in rice were found in the husks (73.61%), bran (10.09%) and milled rice (19.52%), respectively. Our results indicated that there is no significantly perchlorate exposure risk in edible milled rice. We suggested that perchlorate in rice can be greatly removed if deep processed unhusked rice and there is no perchlorate exposure risk in edible milled rice.

Detection of basmati rice using microsatellite markers

Basmati rice is a fine and aromatic rice grown mainly in certain areas of Punjab province in Pakistan. It has high demand in the international market and a source of earning foreign exchange via export. Adulteration of non-basmati rice grains is a major challenge to secure its export standards. Hence, the development of a simple and cost-effective method is necessary to screen the basmati and non-basmati rice samples. In this study, we have validated the efficiency of different molecular markers by screening seven unknown rice samples. Our results demonstrated that three markers namely RM1, RM19 and RM225 proved to be efficient microsatellite molecular markers that could be used to screen basmati and non-basmati rice samples. Further, these results are validated based on expression pattern of Badh2 gene among the basmati and non-basmati rice. Thus, this study provides a contribution towards development of a simple and cost-effective method for rapid screening of basmati rice.

Screening of blast resistance genes in rice breeding samples

Rice is one of the most widespread and cultivated crops in the world. It is necessary to increase the yield of crops or expand their sown areas to resolve a food security problem in Russia. Current impossibility of expanding rice cultivated areas in the Rostov region and the need to maintain and increase its yield require developing new disease-resistant varieties. Rice genotypes with multiple blast resistance genes avoid significant yield losses. Since pyramiding and selection of resistance genes in the same genotype through traditional selection methods are complicated, it is urgent to search for homozygous samples using marker-assisted selection methods. This study was aimed to identify Pi-1, Pi-2, Pi-33 and Pi-ta blast resistance genes in breeding rice samples by MAS-methods. The study used CTAB-method for DNA-isolation, PCR, electrophoresis on agarose and polyacrylamide gels. The resulting gels were stained in a solution of ethidium bromide and photographed in ultraviolet light. To control the presence of blast resistance genes the following parental cultivars were used: C104LAC for the Pi-1 and Pi-33 genes, C101-A-51 for the Pi-2 gene, IR36 for the Pi-ta gene; Novator and Boyarin as controls of non-functional alleles of all studied genes. The 446 selection samples of the seventh generation were analyzed. As a result of the research, 127 rice samples that combine 2 or 3 different blast resistance genes were identified. The Pi-2 and Pi-33 genes combination was identified in 43 samples (1128/1, 1149/3, 1171/2, 1177/3, 1177/4, 1186/4, et al.). Samples with three resistance genes are the most interesting for selection and further breeding. For developing new blast-resistant varieties, we recommend using rice samples with the following combinations of resistance genes Pi-1+Pi-2+Pi-33 (1197/1, 1226/2, 1271/1, 1272/2), Pi-1+Pi-2+Pi-ta (1197/4, 1304/2, 1304/3, 1482/3, 1482/4, 1486/1) and Pi-2+Pi-33+Pi-ta (1064/1, 1064/3, 1281/2, 1281/3, 1281/4, 1282/2, 1283/1, 1283/2, 1284/3).

Physical and Nutritional Properties of Local Hawm Gra Dang Ngah Rice Varieties

Information on the local rice varieties grown in each Tambon (subdistrict), community or part of Thailand is still outdated. The present pilot work aimed to determine physical characteristics (grain dimensions, 1000-grain weight and color parameters) of paddy and dehusked rice in order to enhance the nutritional quality of these varieties. Moreover, it further supports cultivation of local Hawm Gra Dang Ngah (HGDN) rice in Narathiwat to ultimately develop to commercial premium quality. The nutritional values of dehusked rice were also compared among Tambons, as well as between the dehusked rice of local HGDN versus pure line selection HGDN PTNC09002-59. The study analysed rice samples grown locally in 4 Tambons: Bangkhunthong, Phron, Praiwan and Salamai in Takbai Amphoe (district), Narathiwat, Thailand. The main findings in this study revealed that medium and long types of both paddy and dehusked rice were all found in each Tambon. Moreover, local dehusked HGDN grain was darker red-brown color. All Tambons were found to contain comparable nutrient levels. High levels of dietary fiber were detected in all Tambons. Overall, the dehusked HGDN rice grown in Bangkhunthong showed the highest levels of vitamin B2 and calcium. The dehusked HGDN (100 g/dry weight) in Bangkhunthong, Phron, Praiwan and Salamai contains protein; 8.73±0.01, 7.65±0.00, 8.22±0.03 and 6.83±0.03, iron; 8.73±0.01, 7.65±0.00, 8.22±0.03 and 6.83±0.03, ash; 1.19±0.00, 0.75±0.00, 1.10±0.00 and 1.34±0.00. These findings provide new information about local HGDN, and may be utilized to support the agricultural community in Takbai, enabling the selection of optimal HGDN varieties for local commercial use, as well as in breeding programs, to facilitate the promotion of local HGDN in the national Thai rice market.

Characteristics of Physicochemical Properties of Chalky Grains of Japonica Rice Generated by High Temperature during Ripening

Global warming has caused devastating damage to starch biosynthesis, which has led to the increase in chalky grains of rice. This study was conducted to characterize the qualities of chalky rice grains and to develop the estimation formulae for their quality damage degree. We evaluated the chalkiness of 40 Japonica rice samples harvested in 2019, in Japan. Seven samples with a high ratio of chalky rice grains were selected and divided into two groups (whole grain and chalky grain). As a results of the various physicochemical measurements, it was shown that the surface layer hardness (H1) of cooked rice grains from chalky grains was significantly lower, and their overall hardness was significantly lower than those from the whole grains. In addition, α- and β-amylase activities, and sugar contents of the chalky rice grains were significantly higher than those of the whole rice grains. The developed estimation formula for the degree of retrogradation of H1 based on the α-amylase activities and pasting properties, showed correlation coefficients of 0.84 and 0.81 in the calibration and validation tests, respectively. This result presents the formula that could be used to estimate and to characterize the cooking properties of the rice samples ripened under high temperature.

Identification of Saltol QTL in the breeding rice samples

One of the main problems in most of the world rice-growing regions is soil salinity. Rice is considered a saline sensitive crop, especially at the early stages of development and in the period of maturity. In the Rostov region, rice is grown in the south-eastern parts, where there are currently difficulties with the operation of the existing reclamation facilities. The problem of saline soils for this region is especially urgent, since a significant part of the arable lands has alkali complexes. In order to return the saline lands into exploitation, it is necessary to develop salt tolerant varieties, which, under crop rotation and maintenance, can contribute to soil desalinization. Due to the difficulty of determining salt tolerance only by estimating the phenotype, it is necessary to use molecular markers associated with this trait. Thus, the purpose of the current work was to identify one of the main Saltol QTL in breeding rice samples of the eighth generation (F8) obtained from hybridizing the donor variety NSYC Rc106 with Russian varieties. For that purpose, there have been used such marker-assisted selection methods as DNA isolation, polymerase chain reaction (PCR), electrophoresis on 2% agarose gels, gels’ coloring in ethidium bromide solution, photography in ultraviolet light and evaluation of the obtained electrophoregrams. As a result of the study of 398 breeding rice samples, there have been identified 67 samples with the functional allele of Saltol QTL (6865/3, 6874/2, Don 7343/4, Don 7343/5, Don 7343/6, Don 7343/7, Don 7343/8, Don 7343/9, Don 7343/10, Don 7337/1, Don 7337/3, Don 7337/4, Don 7337/5, Don 7337/6, Don 7337/7, Don 7337/8, etc.). There have been recommended to use these samples in the further breeding process in order to develop new salinity resistant rice varieties.

Genetic analysis of the hybrid rice population ‘Mavr × Kontakt’

Rice can form not only white-color kernels, but also of red, brown and black colors. In black-color rice kernels, the pericarp contains anthocyanin, which has antioxidant activity and therefore has a positive effect on human health. The purpose of the current study was to develop rice samples with black pericarp. The paper has presented the study results of the hybrid population ‘Mavr × Kontakt’ of the second generation. The variety ‘Mavr’ has a black pericarp, the variety ‘Kontakt’ has a white one. In the process of hybridological analysis there have been identified the patterns of inheritance of the main quantitative traits affecting productivity; there have been identified the best samples, in which formed compact erect panicles and black kernels; there has been selected the initial material for breeding work. The study was carried out in 2020 on the plots of the ES “Proletarskoye” in the Rostov region. There was established that the color of pericarp was inherited according to the type of complementary interaction of two genes. There was found an overdominance and interaction of two pairs of genes of different strengths according to ‘plant height’. There was also seen partial positive dominance, transgressions, and digenic differences of the initial varieties according to ‘panicle length’. According to the traits ‘number of spikelets per panicle’, there was identified overdominance of large values and positive transgression. There were found the forms with well-kerneled panicles. The trait ‘1000 kernel weight’ was characterized by negative dominance and dihybrid cleavage of 9:6:1. There have been selected the best morphotype F2 forms with black pericarp, which possessed optimal plant height, long panicles, larger kernel size, and an average 1000 kernel weight.

Justification of the choice of raw materials for the production of vegetable milk

The article presents the results of a study of the quality of rice of breeding varieties "Syr syluy", "Aikerim", "Marzhan" LLP "Kazakh Rice Research Institute named after I. Zhakhaev". During the study, rice samples were evaluated physico-chemical, biochemical, technological properties and safety indicators. All the studied samples of rice grains in terms of safety meet the requirements of the Technical Regulations of the Customs Union "On grain safety". The result of the implementation of this research will be the expansion of the range of beverages for healthy and safe nutrition of the population.