Evaluation of highly starchy potato varieties by the intensity of starch accumulation and the size of starch grains

В 2018-2020 годах проведено сравнительное изучение высококрахмалистых сортов картофеля по интенсивности накопления крахмала и размеру крахмальных зерен. Полевые и лабораторные исследования выполнены на экспериментальных базах «Пышлицы» и «Коренево» ФИЦ картофеля имени А.Г. Лорха (Московская область). В качестве исходного материала в опытах использовали шесть сортов картофеля собственной селекции среднераннего (Артур, Садон) и среднеспелого (Авангард, Каскад, Накра, Синеглазка 2016) сроков созревания. Объект исследования – нативный крахмал, полученный по ГОСТ 7699-78 из клубней для определения размера крахмальных зерен безмикроскопным методом. Установлена вариабельность крахмалистости изученных сортов с учетом генотипических особенностей, сроков созревания и условий выращивания. Выявлены наиболее стабильные по уровню крахмалонакопления в клубнях сорта Артур, Каскад, Накра и Синеглазка 2016. Различия в крахмалистости между средними и мелкими клубнями одного и того же сорта более существенны в сравнении с различиями между средними и мелкими клубнями. В летней пробе по уровню крахмалистости клубней выделились сорта Накра (20,0%) и Каскад (19,2%) в сравнении с сортом-стандартом Зарево (19,6%), а также сорта Артур и Синеглазка 2016 с крахмалистостью 18,6% и 18,5% соответственно. При анализе высококрахмалистых сортов показано, что в составе крахмала наибольшее количество крахмальных зерен более 57 мкм содержится в клубнях сортов Накра (60,8%), Синеглазка 2016 (60,5%), Каскад (55,7%) и Артур (56,3%). In 2018-2020, a comparative study of high-starch potato varieties was carried out according to the intensity of starch accumulation and the size of starch grains. Field and laboratory studies were carried out at the experimental bases «Pyshlitsy» and «Korenevo» FPRC of named after A.G. Lorkh (Moscow region). Six varieties of potatoes of their own selection of medium-early (Artur, Sadon) and medium-ripe (Avangard, Kaskad, Nakra, Sineglazka 2016) maturation dates were used as the starting material in the experiments. The object of research is native starch obtained according to GOST 7699-78 from tubers for determining the size of starch grains by a non microscopic method. The variability of the starch content of the studied varieties was established, taking into account genotypic features, maturation periods and growing conditions. The most stable in terms of starch accumulation in tubers of the varieties Artur, Kaskad, Nakra and Sineglazka 2016 were identified. Differences in starchiness between medium and small tubers the same varieties are more significant in comparison with the differences between medium and small tubers. In the summer sample, according to the level of starchiness of tubers, the varieties Nakra (20.0%) and Kaskad (19.2%) were distinguished in comparison with the standard variety Zarevo (19.6%), as well as the varieties Artur and Sineglazka 2016 with a starchiness of 18.6 and 18.5%, respectively. When analyzing highly starchy varieties, it was shown that the largest number of starch grains in the starch composition is more than 57 microns contained in the tubers of the varieties Nakra (60.8%), Sineglazka 2016 (60.5%), Kaskad (55.7%) and Artur (56.3%).

Metagenomic analysis exploring taxonomic and functional diversity of bacterial communities of a Himalayan urban fresh water lake

Freshwater lakes present an ecological border between humans and a variety of host organisms. The present study was designed to evaluate the microbiota composition and distribution in Dal Lake at Srinagar, India. The non-chimeric sequence reads were classified taxonomically into 49 phyla, 114 classes, 185 orders, 244 families and 384 genera. Proteobacteria was found to be the most abundant bacterial phylum in all the four samples. The highest number of observed species was found to be 3097 in sample taken from least populated area during summer (LPS) whereas the summer sample from highly populated area (HPS) was found most diverse among all as indicated by taxonomic diversity analysis. The QIIME output files were used for PICRUSt analysis to assign functional attributes. The samples exhibited a significant difference in their microbial community composition and structure. Comparative analysis of functional pathways indicated that the anthropogenic activities in populated areas and higher summer temperature, both decrease functional potential of the Lake microbiota. This is probably the first study to demonstrate the comparative taxonomic diversity and functional composition of an urban freshwater lake amid its highly populated and least populated areas during two extreme seasons (winter and summer).

Study on Season Factor in the Preparation of PVA/RS Composite

The effect of season factor on the performances of poly (vinyl alcohol)/rice straw (PVA/RS) composites prepared by hot-pressing was studied. Two forms of RS, including shortcut RS and RS wires, were used to prepare composite. For PVA/ shortcut RS composites, samples of winter showed higher tensile strength and strength at tensile fracture at different PVA contents than that of summer. When PVA content is 50%, tensile strength of winter sample is 136% higher than that of summer sample and strength at tensile fracture of winter sample is 320% higher than that of summer sample. In addition, samples of winter showed lower tensile stretch and higher hardness at different PVA contents than that of summer. For PVA/RS wire composites, the comparison results are similar. These indicated that season is an important factor for preparing plant based composite with PVA as adhesive.

Chemical Composition and Biological Activities of the Essential Oil of Mentha suaveolens Ehrh.

Hydrodistilled oils of the fresh aerial parts of Mentha suaveolens Ehrh. cultivated in Egypt were prepared from samples collected along the four seasons. The percentage yields of these essential oils were 0.50%, 0.52%, 0.60%, and 0.47% of the dry weight for winter, spring, summer, and autumn samples. GC/MS analyses of all samples revealed a qualitative and quantitative variability in the oil composition. The total number of compounds identified was 46 among which 15 were common in all samples. The oxygenated compounds constituted about 45%, 46%, 63%, and 44% of the total composition of the oils for winter, spring, summer, and autumn samples, respectively. Carvone was the major constituent in spring, summer, and autumn samples (about 31%, 56%, and 35%, respectively), while limonene (ca. 26%) was the major constituent of the winter sample followed by carvone (ca. 25%). The essential oil of the highest yield (full-fl owering summer sample), with the highest oxygenated constituents and carvone contents, was screened for certain biological activities. It exhibited analgesic and acute anti-inflammatory activities (75% and 82% relative to indomethacin). It also showed a potent in vivo antioxidant activity (96% relative to vitamin E). In addition, it exerted moderate cytotoxic, hepatoprotective, and in vitro antioxidant activities. Moreover, the oil had a potent antifungal activity against Candida albicans (MIC = 4 μg/ml), Saccharomyces cerevisiae (MIC = 5.2 μg/ml), and Aspergillus niger (MIC = 6.8 μg/ml).

Morphometric comparisons of skulls of harbour porpoises (Phocoena phocoena) from the Baltic, Kattegat, and Skagerrak seas

The population structure of harbour porpoises (Phocoena phocoena) in Swedish waters was studied by means of morphometric comparisons of skulls from 103 specimens. The study was designed to investigate whether harbour porpoises in the Baltic Sea form a distinct population separate from animals found in the Kattegat and Skagerrak seas. The Kattegat–Skagerrak (K-S) sample was divided into summer and winter samples to account for possible migrational movements by Baltic Sea animals between breeding seasons. Both multivariate and univariate statistical analyses showed significant differences between three female samples from the Baltic Sea and the Kattegat and Skagerrak seas. Pairwise comparisons showed differences between the Baltic sample and the K-S summer sample in five characters and between the Baltic sample and K-S winter sample in one character. No differences were found between the K-S summer and winter samples. The multivariate analysis did not show separation of male specimens and only one character was significantly different in the univariate analyses. Pairwise comparisons of adjusted means of this character did not reveal significant differences between the samples. The results show that female harbour porpoises in the Baltic Sea are morphologically distinct from females in the Kattegat and Skagerrak seas and these differences probably would not exist if animals from the two areas interbreed. Harbour porpoises in the Baltic Sea should therefore be managed separately and measures should be taken to prevent bycatches of this likely endangered population.