Biological traits of sled dogs of different breeds

Relevance. Recently interest in Siberian and Alaskan huskies has led to a sharp increase in their population, which has led to the relevance of the work carried out.The purpose of the research was to study and evaluate the biological characteristics of sled dogs of different breeds.Methods. The biological traits of sled dogs of Siberian and Alaskan Husky breeds have been carried out with using modern hematological and statistical research methods.Results. The dynamics of hematological indicators in dogs of different breeds before and after exercise has been established. The exercise affected the content of red blood cells — in both groups their decrease occurred (by 7.3 and 11.7%), a similar dynamics has been observed in the level of hemoglobin. The content of white blood cells in both groups, on the contrary, has been increased after exercise. Exercises during the race led to a slight change in the concentration of platelets in the blood of dogs: in Siberian huskies their content has been decreased, while in the group of Alaskan huskies has been increased. The adaptation coefficient of Siberian husky dogs was 4.4 and was higher than in Alaskan huskies by 0.6 or 13.6% (P > 0.999). The heat tolerance index for Siberian huskies was 79.0 and was higher than for Alaskan huskiesb y 8.0 or 11.3% (P > 0.99).

A novel tolerance index to identify heat tolerance in cultivated and wild barley genotypes

Thermal stress at the reproductive stage poses a substantial constraint on cereal production worldwide. A two-year field study was conducted to assess tolerance to terminal heat stress in cultivated (Hordeum vulgare ssp. vulgare L.) and wild (H. vulgare ssp. spontaneum L.) barley genotypes using phenological and agronomic traits as well as selection indices based on grain yield. A new heat-tolerance index was tested while a simultaneous study was also carried out of both phenological and grain yield-related variables as well as previously defined indices. Results of analysis of variance showed the significant genotypic and high-temperature stress (environment) effects on all the traits studied. In contrast to the cultivated genotypes, the wild ones were found less affected by high-temperature stress. Moreover, both cultivated and wild genotypes were observed to use the life cycle shortening as a mechanism to evade heat stress. In addition, supplementary tolerance mechanisms were also found likely to contribute to heat-stress evasion in the wild germplasm. Grain yield showed a strong relationship with both stress tolerance index (STI) and heat tolerance index (HTI) among the wild genotypes. However, multivariate analysis highlighted the feasibility of HTI to screen high-temperature tolerant wild genotypes under harsh environments with the most high-temperature tolerant wild genotypes identified originating from warm climates.

Indices and their Applicability under High Temperature in Potato (Solanum tuberosum L.) Cultivars

The increasing temperature is going to be more vulnerable for cool season crops like potato which requires an optimum productivity temperature of 18 to 20 °C. Thus, breeding for heat tolerance has become very important. Therefore, some previously used indices for abiotic stress tolerance have been used in our study for screening of high temperature stress tolerance in potato. Three high yielding (Kufri jyoti, Kufri megha and Kufri pokraj) and two local (Rangpuria and Badami) commonly grown potato cultivars were selected for our experiment. Potato cultivars were sown under normal condition and two high temperature conditions (polyhouse and early season) and indices such as HSI (heat susceptibility index), HTI (heat tolerance index), GM (geometric mean) and HII (heat intensity index) were used to evaluate the performance of the cultivars under all the three temperature conditions. The positive and significant correlation between HTI (heat tolerance index), and GM (geometric mean) as well as with tuber yield under all the conditions revealed that these indices were efficient in selecting the high temperature tolerant potato cultivars. We recorded the equal applicability of these two indices for both high yielding and local group of potato cultivars. Our study revealed that cultivar Kufri megha and Rangpuria showed higher heat tolerance between high yielding and local cultivars respectively.