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Mechanisms aimed at recovering from heat-induced damages are closely associated with the ability of ectotherms to survive exposure to stressful temperatures. Autophagy, a ubiquitous stress-responsive catabolic process, has recently gained renewed attention as one of these mechanisms. By increasing the turnover of cellular structures as well as the clearance of long-lived protein and protein aggregates, the induction of autophagy has been linked to increased tolerance to a range of abiotic stressors in diverse ectothermic organisms. However, whether a link between autophagy and heat-tolerance exists in insect models remains unclear despite broad ecophysiological implications thereof. Here, we explored the putative association between autophagy and heat-tolerance using Drosophila melanogaster as a model. We hypothesized that (i) heat-stress would cause an increase of autophagy in flies' tissues, and (ii) rapamycin exposure would trigger a detectable autophagic response in adults and increase their heat-tolerance. In line with our hypothesis, we report that flies exposed to heat-stress present signs of protein aggregation and appear to trigger an autophagy-related homoeostatic response as a result. We further show that rapamycin feeding causes the systemic effect associated with target of rapamycin (TOR) inhibition, induces autophagy locally in the fly gut, and increases the heat-stress tolerance of individuals. These results argue in favour of a substantial contribution of autophagy to the heat-stress tolerance mechanisms of insects. [ABSTRACT FROM AUTHOR]

IntroductionHeat stress is one of the main threats for the seaweed aquaculture, leading to the decay of the blades and causing serious economic losses. A newly developed biostimulant, Sargassum horneri extract (SHE), can enhance the heat-tolerance in Neopyropia yezoensis, which can be applied in the seaweed aquaculture. However, the molecular mechanism underlying this acquired heat-tolerance is still unclear.MethodIn this study, we examined the transcriptional regulation of N. yezoensis under heat stress after the SHE pre-treatment by performing the RNA-Seq on illumina Novaseq platform and differentially expressed gene analysis.Result and discussionOur results show that, under heat stress, the SHE pre-treatment can alleviate the suppression of genes involved in normal cell activities, such as ribosome biogenesis, photosynthesis, respiration and cell cycle. On the other hand, SHE pre-treatment can also induce some key genes involved in the heat-tolerance. We also found that the combination of SHE pre-treatment and heat stress can induce some genes related to epigenetic modification, suggesting that SHE may facilitate the formation of heat stress memory in N. yezoensis. Our study provides information for understanding the molecular mechanism of heat-tolerance in N. yezoensis and for promoting the application of seaweed-derived biostimulants in the seaweed aquaculture.

Reproductive parameters of dairy animals are generally affected by meteorological factors. This study aimed to investigate the effects of heat stress (HS) on reproductive parameters Saanen and Saanen× Red Maradi (½S½RM) dairy goats reared on a private farm in a tropical sub-humid environment in Benin. To assess the reproductive performances 103 goats (46 Saanen and 57 ½S½RM) were followed up from January 2015 to December 2019. The temperature-humidity index (THI) was obtained during the same period using meteorological data such as ambient temperature (AT) and relative humidity (RH). Pearson correlation matrix analysis was then performed between the environmental variables and the reproductive parameters. Reproductive parameters of ½S½RM goats were better than those of Saanen goats. The conception (92.09%), prolificacy (156.54%) and fecundity (117.11%) rates of ½S½RM goats were significantly higher than those of Saanen goats (67.16%; 149.41% and 89.70%). The conception rate of Saanen goats was not affected by the level of THI. The conception, prolificacy, and fertility rates of ½S½RM goats decreased from 97.22%, 161.35% and 121.52%, at moderate THI to 83.89%, 148.86%, and 110.04% at extreme THI, respectively. In summary, although Saanen goats were very efficient in milk production, their reproductive performance was affected by the level of THI. On the contrary, the ½S½RM crossbred goats had a better conception, prolificacy and fertility rates in the sub-humid tropical climate of Benin.

Periods of high temperature and an expected increase in atmospheric CO2 concentration as a result of global climate change are major threats to wheat (Triticum aestivum L.) production. Developing heat-tolerant wheat cultivars demands improved understanding of the impacts of high temperature and elevated CO2 on plant growth and development. This research investigated the interactive effects of heat stress and CO2 concentration on pollen viability and its relationship to grain formation and yield of wheat in greenhouse conditions. Nineteen wheat genotypes and a current cultivar, Suntop, were heat stressed at either meiosis or anthesis at ambient (400 µL L–1) or elevated (800 µL L–1) CO2. Elevated CO2 and heat stress at meiosis reduced pollen viability, spikelet number and grain yield per spike; however, increased tillering at the elevated CO2 level helped to minimise yield loss. Both heat-tolerant genotypes (e.g. genotype 1, 2, 10 or 12) and heat-sensitive genotypes (e.g. genotype 6 or 9) were identified and response related to pollen sensitivity and subsequent impacts on grain yield and yield components were characterised. A high-throughput protocol for screening wheat for heat stress response at elevated CO2 was established and meiosis was the most sensitive stage, affecting pollen viability, grain formation and yield. Changing climate poses a threat to Australian wheat (Triticum aestivum L.) production. Hence, there is a priority for breeding heat-tolerant wheat varieties. In this study, several heat-tolerant wheat genotypes were grown in simulated warmer climate and elevated CO2 and analysed for pollen viability, grain formation and yield. We established a protocol where pollen viability is an important trait for screening heat-tolerant wheat progenies for sustainable wheat yield at projected climate change conditions. [ABSTRACT FROM AUTHOR]

Poly(m-phenylene isophthalamide) (PMIA) membranes are promising heat-tolerant separator candidates of lithium-ion batteries (LIBs), while their wettability toward carbonate electrolyte and corresponding batteries performance are not desirable. Herein, PMIA membranes coated with ultrathin mussel-inspired polydopamine (PDA) layer were fabricated as separators in LIBs. The introduced amino, quinonyl, and catechol groups in PDA coating could enhance the wettability of the resultant PMIA-PDA separator toward electrolyte. The PMIA-PDA separator had excellent thermal stability, showing a thermal shrinkage of 5.2% at 200 °C. The contact angle of the thermal-treated PMIA-PDA separator could maintain at 26.1°, which decreased by 42.7% compared with the pristine PMIA separator. The PMIA-PDA separator also displayed a high ionic conductivity (0.86 mS cm−1) and a low interfacial electric resistance (62.4 Ω). Consequently, the assembled LiCoO2/PMIA-PDA/Li battery achieved good cyclic stability with the capacity retention of 84.3% (121.1 mAh g−1) after 100 cycles under 30 °C. More significantly, the relevant capacity retention remained at 89.0% (127.5 mAh g−1) under 60 °C, which implied a great potential of PMIA-PDA membranes as separators of high-safety LIBs. [ABSTRACT FROM AUTHOR]

The macro “PollenCounter” in ImageJ was initially developed to assess pollen viability in grapevine. We set out to see if PollenCounter could be used to assess pollen number and viability in tomatoes. • We tested different optimization scenarios by adjusting the pollen size (100–900, 200–900 pixel2) and circularity of pollen grains (0.4–1, 0.5–1, and 0.6–1) on 31 microscopic images of stained tomato pollen. Both total pollen number and proportion of viable pollen were positively and significantly correlated with the outputs from manual counting. The scenario with 100–900 pixel2 pollen size and 0.4–1 circularity had the highest association for pollen number (r = 0.99) and pollen viability (r = 0.86). PollenCounter is 32-fold faster than manual counting. • We added a command to the macro to automatically save the outputs containing the number of total and viable pollen, avoiding transcription errors inherent to manual counting. • We successfully applied the optimized PollenCounter to discriminate tomato genotypes based on pollen number and pollen viability under heat stress. Our results show that PollenCounter, as an open-access macro, can be customized and improved to meet users’ needs. The use of PollenCounter can save time and money in pollen quality assessment. We outline the steps to optimize the macro for other samples or crop species. The optimized macro could allow efficient screening of a large germplasm collection for pollen thermo-tolerance and selection of best thermo-tolerant individuals in breeding programs.

Heat stress (HS) adversely influences dairy cattle welfare and productivity. This study aimed to investigate the effects of HS on production and physiological parameters of Holstein cows. Two experiments each lasted 6 weeks were conducted in four Tunisian farms, firstly during summer under HS (n = 80, THI = 77) and later during autumn under thermo-neutral (n = 80, THI = 54) conditions. Respiration rate (RR), skin temperature (ST), rectal temperature (RT) and milk yield were measured, and milk samples were collected on 2 days every week during each experimental period. Temperature and relative humidity were measured inside the barn to calculate the temperature-humidity index (THI). Mixed models were used to evaluate the effects of period and the relationships between THI and physiological and production traits. Reaction norm models were applied to quantify the individual responses of cows across the trajectory of THI during the HS period. A clustering methodology was developed to identify tolerant and sensitive cows to HS based on their slope for response of physiological and production traits during HS period. In summer, RR (61 breaths/min) and ST (37.7 °C) were 2.3- and 1.3-fold higher, whereas milk yield per milking was 24% lower compared with thermo-neutral conditions. Linear relationship between THI and RR, ST and RT was observed and showed increases by 2 breaths/min, 0.5 °C and 0.04 °C per increase in one THI unit, respectively. Inversely, milk, fat and protein yields showed a drop of 0.13 kg, 0.4 g and 0.3 g per milking per increase in one THI unit, respectively. Cows qualified to be heat tolerant by our work tended to have higher RR, ST, and RT and lower to almost no decay in milk yield compared to cows qualified to be heat sensitive. Specifically, RR could be used as a reliable indicator for thermotolerance. The results of this study deepen our understanding of different aspects of HS resilience. • Heat stress alter production and physiological traits of Holstein cows. • Large individual response variability has been identified for Holstein cows. • Skin temperature and respiration rate allow an early detection of Heat stress. • Tolerant cows tended to have higher physiological traits especially respiration rate. [ABSTRACT FROM AUTHOR]

High-temperature stress (HTS) at the grain-filling stage in spring maize (Zea mays L.) is the main obstacle to increasing productivity in the North China Plain (NCP). To solve this problem, the physiological mechanisms of HTS, and its causes and impacts, must be understood. The HTS threshold of the duration and rate in grain filling, photosynthetic characteristics (e.g., the thermal stability of thylakoid membrane, chlorophyll and electron transfer, photosynthetic carbon assimilation), water status (e.g., leaf water potential, turgor and leaf relative water content) and signal transduction in maize are reviewed. The HTS threshold for spring maize is highly desirable to be appraised to prevent damages by unfavorable temperatures during grain filling in this region. HTS has negative impacts on maize photosynthesis by damaging the stability of the thylakoid membrane structure and degrading chlorophyll, which reduces light energy absorption, transfer and photosynthetic carbon assimilation. In addition, photosynthesis can be deleteriously affected due to inhibited root growth under HTS in which plants decrease their water-absorbing capacity, leaf water potential, turgor, leaf relative water content, and stomatal conductance. Inhibited photosynthesis decrease the supply of photosynthates to the grain, leading to falling of kernel weight and even grain yield. However, maize does not respond passively to HTS. The plant transduces the abscisic acid (ABA) signal to express heat shock proteins (HSPs), which are molecular chaperones that participate in protein refolding and degradation caused by HTS. HSPs stabilize target protein configurations and indirectly improve thylakoid membrane structure stability, light energy absorption and passing, electron transport, and fixed carbon assimilation, leading to improved photosynthesis. ABA also induces stomatal closure to maintain a good water status for photosynthesis. Based on understanding of such mechanisms, strategies for alleviating HTS at the grain-filling stage in spring maize are summarized. Eight strategies have the potential to improve the ability of spring maize to avoid or tolerate HTS in this study, e.g., adjusting sowing date to avoid HTS, breeding heat-tolerance varieties, and tillage methods, optimizing irrigation, heat acclimation, regulating chemicals, nutritional management, and planting geometric design to tolerate HTS. Based on the single technology breakthrough, a comprehensive integrated technical system is needed to improve heat tolerance and increase the spring maize yield in the NCP.

Weed competition during spears harvesting reduces asparagus yields. The application of herbicides during this period is illegal, and alternative non-chemical practices are needed. This research tested the effectiveness and efficiency of a custom-built combined flamer-cultivator to control weeds (both in the inter- and intra- spears production bands) during the spears harvest season. It also analysed the effects of various liquefied petroleum gas (LPG) doses on total asparagus yield, mean spear weight, and total number of marketable spears. In both years, the asparagus spears were generally not damaged by flame weeding using LPG doses of between 43 to 87 kg/ha. The same LPG doses were effective in controlling weeds, showing the same total marketable yields as the weed-free control. At high LPG doses (e.g. 130 and 260 kg/ha), yields decreased as a consequence of the damage caused to the spears, resulting in a lower number of marketable spears. Flaming did not affect the mean spear weight, and can be applied repeatedly during harvesting to maintain the weeds at a level that does not lead to a yield reduction. The repeated use of the combined flamer-cultivator (every seven days) led to higher yields than plots where weed control was not conducted. The new machine can be used in a period when herbicides are not possible. Flaming could be introduced by asparagus producers as an alternative, or in addition to herbicides applied in the pre-emergence and post-harvest of spears.

Background: The free-living amoebae Acanthamoeba spp., have been recognized as etiologic agents of amoebic encephalitis, keratitis, otitis, lung lesions and other skin infections mainly in immuno-compro­mised individuals. In this study, morpho-physiological and biochemical characterization of Acanthamoeba strains isolated from the Egyptian aquatic environment were surveyed.Methods: some Acanthamoeba species were cultivated on non-nutrient agar. Isolated strains of Acantha­moeba were identification based on the morphology of trophic and cyst forms in addition to temperature and osmo-tolerance assays. Biochemical characterization of the isolated amoeba strains was performed using quantitative assay as well as qualitative determination of proteolytic activity in zymograph analysis.Results: Potentially pathogenic Acanthamoeba species were isolated from all of the examined water sources. Colorimetric assays showed protease activity in the heat-tolerant isolates of Acanthamoeba. All pathogenic isolates of Acanthamoeba exhibited higher protease activity than did the non-patho­genic ones. The zymographic protease assays showed various banding patterns for different strains of Acanthamoeba.Conclusio: The incidence and prevalence of the pathogenic Acanthamoeba species in the aquatic environment using parasitological and biochemical diagnostic tools will provide baseline data against which the risk factors associated with waterborne transmission can be identified.

High temperature in summer is a major limiting factor for the growth of snap bean in the subtropical islands of Okinawa, Japan. The effect of temperature on biomass production, yield components, and morphological characters were studied in five snap-bean cultivars and strains in the phytotron. Plants were initially grown at 24/20ºC (day/night temperature, 12/12hr) and transferred to 24/20ºC, 27/23ºC (control) or 30/26ºC at the onset of flowering (34 days after sowing). High temperature (30/26ºC) increased single pod weight and the number of flowers and branches, but reduced the number of pods/plant, pod set ratio, and plant weight. ‘Haibushi’, a heat-tolerant cultivar, had higher pod weight/plant, number of pods/plant, pod weight/pod, pod set ratio, number of branches, and rate of biomass allocation to pods, but lower rates of biomass allocation to leaves, stems, and roots than ‘Kentucky Wonder’, a heat-sensitive cultivar, in all temperature regimes. The number of flowers, biomass, and accumulative temperature affected both the yield components (number of pods/plant, single pod weight) antithetically. The yield components were estimated by a stepwise multiple regression analysis. The number of pods/plant was estimated from the number of flowers, leaf weight, pod set ratio per branch, and plant weight with a reasonable precision (R2=0.78). Single pod weight was determined (R2=0.69) from pod set ratio, number of branches, root weight, and accumulative temperature. The results indicated that higher biomass allocation to pods and higher pod set in branches, which were observed in heat-tolerant cultivars at all temperature regimes, were most effective for the estimation of heat tolerance in snap bean.

Lactobacillus kefiranofaciens M1 (M1) has been shown to possess many different beneficial health effects including anti-colitis activity. The purpose of this study was to develop a novel and easily scaled-up encapsulating technique that would improve the temperature tolerance of the bacterium and reduce the sensitivity of the organism to gastrointestinal fluid. A mixture of sodium alginate, gellan gum and skim milk powder was used as a coating material to entrap M1. The M1 gel was then directly freeze dried in order to dehydrate the covering and form microcapsules. The viable cell numbers of M1 present only dropped ten folds after the freeze-drying encapsulation process. The viable cell counts remained constant at 5 × 10 7 CFU/g after heating from 25 °C to 75 °C and holding at 75 °C for 1 min. The viable cell counts were reduced to 10 6 CFU/g and 10 5 CFU/g after 8-week storage at 4 °C and subsequent heat treatment with simulated gastrointestinal fluid test (SGFT) and bile salts, respectively. The effect of encapsulated M1 on the organism's anti-colitis activity was evaluated using the dextran sodium sulfate (DSS) induced colitis mouse model. An in vivo study indicated that administration of heat treated encapsulated M1 was able to ameliorate DSS-induced colitis producing a significant reduction in the bleeding score and an attenuation of inflammatory score. These findings clearly demonstrate that encapsulation of M1 using this novel technique is able to provide good protection from temperature changes and SGFT treatment and also does not affect the organism's anti-colitis activity. [ABSTRACT FROM AUTHOR]

Background: The free-living amoebae Acanthamoeba spp., have been recognized as etiologic agents of amoebic encephalitis, keratitis, otitis, lung lesions and other skin infections mainly in immuno-compromised individuals. In this study, morpho-physiological and biochemical characterization of Acanthamoeba strains isolated from the Egyptian aquatic environment were surveyed. Methods: some Acanthamoeba species were cultivated on non-nutrient agar. Isolated strains of Acanthamoeba were identification based on the morphology of trophic and cyst forms in addition to temperature and osmo-tolerance assays. Biochemical characterization of the isolated amoeba strains was performed using quantitative assay as well as qualitative determination of proteolytic activity in zymograph analysis. Results: Potentially pathogenic Acanthamoeba species were isolated from all of the examined water sources. Colorimetric assays showed protease activity in the heat-tolerant isolates of Acanthamoeba. All pathogenic isolates of Acanthamoeba exhibited higher protease activity than did the non-patho-genic ones. The zymographic protease assays showed various banding patterns for different strains of Acanthamoeba. Conclusion: The incidence and prevalence of the pathogenic Acanthamoeba species in the aquatic environment using parasitological and biochemical diagnostic tools will provide baseline data against which the risk factors associated with waterborne transmission can be identified.

The Buda Arboretum was initiated in the winter of 1893/94. Now it covers 7.5 hectares and is surrounded by the constantly growing city of Budapest. At present, the Arboretum is under very strong urban effect. Within the framework of a EU-project "Preservation and Restoration of Living Plant Collections and Historical Gardens" the Buda Arboretum was profoundly reconstructed and developed between 2010-2012. There were reconstructed selected objects serving to special purposes, e.g.: 1. Special biotypes (garden pond and the surrounding wetland, rock-gardens, pergolas for the climbing plants; a retaining wall giving shelter for the Mediterranean collections; greenhouse as a biotope for tropical and subtropical plants), 2. The historic geometrical garden part (called Parade Square), 3. Ecological solutions for water supply, 4. Suppression of invasive species and development of Laurocerasus, Malus, Potentilla, Prunus, Syringa collections, wetland-perennials, collection of Hungarian bred woody ornamentals introduction and trial of new Mediterranean species, etc. After reconstruction, the plant material includes over 1,900 woody species and cultivars, more than 240 kinds of bulb-flowers, 500 different perennials, 250 annuals and round about 300 tropical and subtropical (greenhouse) taxa. [ABSTRACT FROM AUTHOR]

Background: The free-living amoebae Acanthamoeba spp., have been recognized as etiologic agents of amoebic encephalitis, keratitis, otitis, lung lesions and other skin infections mainly in immuno-compromised individuals. In this study, morpho-physiological and biochemical characterization of Acanthamoeba strains isolated from the Egyptian aquatic environment were surveyed. Methods: some Acanthamoeba species were cultivated on non-nutrient agar. Isolated strains of Acanthamoeba were identification based on the morphology of trophic and cyst forms in addition to temperature and osmo-tolerance assays. Biochemical characterization of the isolated amoeba strains was performed using quantitative assay as well as qualitative determination of proteolytic activity in zymograph analysis. Results: Potentially pathogenic Acanthamoeba species were isolated from all of the examined water sources. Colorimetric assays showed protease activity in the heat-tolerant isolates of Acanthamoeba. All pathogenic isolates of Acanthamoeba exhibited higher protease activity than did the non-pathogenic ones. The zymographic protease assays showed various banding patterns for different strains of Acanthamoeba. Conclusion: The incidence and prevalence of the pathogenic Acanthamoeba species in the aquatic environment using parasitological and biochemical diagnostic tools will provide baseline data against which the risk factors associated with waterborne transmission can be identified. [ABSTRACT FROM AUTHOR]

The effect of colemanite additives on sintering and the properties and microstructure of spodumene ceramic is studied. It is found that to identify the sintering and formation processes of a higher-density structure of ceramic it is most effective to introduce colemanite in the amounts 5 - 7%. Spodumene ceramic with CLTE (9.8 - 12.9) × 10 K, heat-tolerance greater than 100 heat cycles (800°C - water), water absorption 0.7 - 5.0%, and mechanical strength under bending 33 - 44 MPa, which all obtain at the sintering temperature 1200°C, was obtained. [ABSTRACT FROM AUTHOR]

Abstract: The changes in chlorophyll a fluorescence, caused by high temperature (HT), have been used to study heat-tolerance in nine common bean (Phaseolus vulgaris L.) accessions (3 cultivars and 6 lines) available in the gene banks of Maritsa Vegetable Crops Research Institute and Institute for Plant Genetic Resources. The plants were grown in controlled greenhouse conditions until the blossoming stage, treated with HT (45°C) for 2h and returned for recovery for 4h at 23°C. The obtained results allowed us to differentiate four groups, among the studied bean plants, by their response to HT. The first group, includes a single cultivar – ‘Secuntsa’. The accession was considered heat sensitive, because it showed a decrease of its total performance index (PI total ), calculated by JIP-test, during HT stress and did not recover to the initial values. The second group, comprised of lines RH13, BBSR17, BBSR28, and ‘Starozagorski cher’, expressed an increase in PI total during heat stress, which however was followed by a decline in PI total values during recovery after HT treatment. The third group – RRR46 displayed a decrease in various JIP-test parameters during HT treatment followed by full recovery after returning the plants to 23°C. The accessions from the fourth group RH26D, ‘Ranit’, similarly to the control heat tolerant line 83201007 did not show significant alteration in PI total . We assumed that the accessions from the fourth group are heat-tolerant. The line RRR46 is also promising in terms of heat tolerance because of its flexible response to HT treatment. These genotypes will be used in our further breeding program. [Copyright &y& Elsevier]

The photosynthetic responses to moderately high temperatures (38 °C, imposed at 21% or 2% O2 in air and 1500 μmol m−2 s−1) were compared in wheat (Triticum aestivum L.) cultivars grown in northern regions of Ukraine and expected to be relatively sensitive to high temperatures (‘North’ cultivars) and in cultivars grown in southern regions and expected to be relatively heat-tolerant (‘South’ cultivars). Heating intact leaves in 21% O2 for 1 h decreased CO2 assimilation by c. 63% in ‘North’ cultivars and only c. 32% in ‘South’ cultivars, with a decrease in PSII activity being observed in only one of the ‘North’ cultivars. Carboxylation efficiency was decreased by about 2.7-fold in ‘North’ cultivars with no significant effect in ‘South’ cultivars. The maximum rates of carboxylation by Rubisco in vivo, Vcmax, estimated from Farquhar's model, increased more than 2-fold in ‘South’ cultivars and remained unchanged in ‘North’ cultivars while the maximum rate of RuBP regeneration, Jmax, decreased by 53% and 21% in ‘North’ and ‘South’ cultivars, respectively. Where the heat treatment was imposed in 2% O2 this increased (as compared with treatment at 21% O2) the inhibitory effect on CO2 assimilation in tolerant cultivars, but decreased it in sensitive ones. The results suggested that differences in tolerance of moderately high temperatures in wheat relate to the stability of the Rubisco function and to RuBP regeneration activity rather than to the effects on PSII activity or stomatal control. [ABSTRACT FROM PUBLISHER]

Abstract: The temperature induced changes in chlorophyll fluorescence induction parameters (F 0, F m, F v and their ratios) measured by a PEA analyzer were used to screen for heat-tolerance 12 cultivars and lines of common bean (Phaseolus vulgaris L.) available in the germplasm collections of Maritsa Vegetable Crops Research Institute, Plovdiv, and Institute of Plant Genetic Resources, Sadovo, Bulgaria. The experiments were carried out in a selection field of Maritsa Institute. The measurements were made on six different dates during the bean reproductive period (in June–July) when the temperatures were approximately 26°C in the morning to and 42°C at noon. Two lines, known earlier as heat-tolerant were used as controls. We found that most of studied cultivars and lines were heat-sensitive because upon day-course increase of temperatures from 26°C to 42°C they revealed statistically significant increase in initial fluorescence (F 0), simultaneous decreases in maximum fluorescence (F m), and in F v/F 0 ratio. Only two cultivars: Ranit and Nerine RS like the heat-tolerant lines preserved F 0, F m and F v values and F v/F 0 ratio at 42°C similar to those values at 26°C. We have considered these two cultivars as heat-tolerant. They have good productivity and been quality and will be used as parental lines in bean breeding program. [Copyright &y& Elsevier]

• Accelerometer-based ear tag sensors can monitor all phases of panting in cattle. • Heat-susceptible and heat-tolerant cattle exhibit contrasting behaviour profiles. • Cattle with high growth potential appeared to be more heat-susceptible. Cattle heat stress responses elicit behavioural adaptation in the form of elevated respiration rate and panting with phase shifts (with increasing severity from closed mouth panting to closed mouth with drool, open mouth, and to open mouth with tongue out) and from "rapid-shallow" to "slow-deep" breathing with increasing temperature. Accelerometer-based sensors can accurately monitor cattle behaviour under experimental and commercial conditions, however, the accuracy of such sensors to monitor the different phases of panting is yet to be determined. Also, despite panting duration diversity between individual cattle of the same breed in the same environment, little is known as to why this occurs. Here we assess the ability of ear tag accelerometer sensors to monitor cattle panting severity and the diversity in behavioural response between heat-susceptible and heat-tolerant cattle when exposed to high heat load. A pen of 99 feedlot heifers were fitted with ear tag sensors and individual cattle panting responses were visually monitored for three consecutive heat event periods. Minute-level panting and non-panting individual cattle data as recorded by sensors were tested against visual observations. Sensitivity (Se), Specificity (Sp), and Youden index (J = Se + Sp – 1) were calculated as test diagnostics for sensor-based classification of panting considering the visual observations as gold standard. Raw minute-level sensor data classified all panting phases with Se 0.30–0.33, Sp > 0.70, and J > 0. Data filtering methods were applied which resulted in systematic improvements in the test diagnostics. Cattle growth, visual panting score (PS) and sensor-detected behaviour duration data were obtained for two selected heat event periods from the same animals. Variability of sensor-detected behaviour durations for visually detected heat-susceptible (PS ≥ 1) and heat-tolerant (PS < 1) category cattle were evaluated by fitting linear mixed models. The heat-susceptible cattle category had greater panting and eating and reduced resting time per day which was most pronounced in the hotter periods of the day. Susceptibility to heat could be attributed to greater growth potential and increasing eating during hotter periods and the associated metabolic heat created. In light of this key finding, adjusting feeding time may reduce the susceptibility of cattle to heat by reducing the heat increment of feeding while environmental heat is at its peak. Overall, the duration of panting and other behaviours across 24 h could be commercially practical for autonomous monitoring of panting severity in cattle, and, from a research perspective, data filtering can improve minute-level accuracy. [ABSTRACT FROM AUTHOR]

Creating mouse models of human genetic disease (Gurumurthy and Lloyd, Dis Models Mech 12(1):dmm029462, 2019) and livestock trait (Schering et al. Arch Physiol Biochem 121(5):194-205, 2015; Habiela et al. J Gen Virol 95 (Pt 11):2329-2345, 2014) have been proven to be a useful tool for understanding the mechanism behind the phenotypes and fundamental and applied research in livestock. A single base pair deletion of prolactin receptor (PRLR) has an impact on hair morphology phenotypes beyond its classical roles in lactation in cattle, the so-called slick cattle (Littlejohn et al. Nat Commun 5:5861, 2014). Here, we generate a knock-in mouse model by targeting the specific locus of PRLR gene using Cas9-mediated genome editing via homology-directed repair (HDR) in mouse zygotes. The mouse model carrying the identical PRLR mutation in slick cattle may provide a useful animal model to study the pathway of thermoregulation and the mechanism of heat-tolerance in the livestock., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Hot season caused boar semen quality decrease. Therefore, ensuring the daily semen production and year-round, stable production of boar semen with superior quality become the basis for a successful reproduction scheme in pig breeding programs. The purpose of this study was to develop an evaluation and testing system of sperm quality traits for selection standards during hot season. The results showed that sperm membrane integrity, intact acrosome, oxidation degree in the Duroc, Landrance and Yorkshire pig of were decrease. Above all, the new technology of production performance verification during the breeding season can be introduced into the modern breeding system, it will be benefit to guide breeding animals to adapt to climate adversity (usually heat and drought) and improve their climate tolerance capacity. [ABSTRACT FROM AUTHOR]

'Solar Fire' is a heat-tolerant hybrid tomato (Solanum lycopersicum L. formerly Lycopersicon esculentum Mill.) with resistance to all three races of Fusarium wilt incited by Fusarium oxysporum f. sp. lycopersici Sacc. Snyder & Hansen. It has superior fruitsetting ability in comparison with most existing cultivars under high temperatures (>32 °C day/>21 °C night), and the fruit crack less under the rainy field conditions often present in the early fall Florida production season. Fla. 7776 is the pollen parent in 'Solar Fire', providing much of the heat tolerance in this hybrid, it has large fruit-providing breeders with a parent to produce heat-tolerant hybrids with two heat-tolerant parents. [ABSTRACT FROM AUTHOR]