红龙鱼鳃部肿瘤的初步研究

对红龙鱼(Scleropages formosus)鳃部肿瘤进行了病理切片研究。结果表明,该肿瘤是由外界不良因素长期刺激导致的腺体大量分泌,纤维素、蛋白、炎症细胞大量分泌纤维化而成的疏松结蹄组织囊肿性肿瘤。

Mutualistic fungal endophytes produce phytohormones and organic acids that promote japonica rice plant growth under prolonged heat stress

This study identifies the potential role in heat-stress mitigation of phytohormones and other secondary metabolites produced by the endophytic fungus Paecilomyces formosus LWL1 in japonica rice cultivar Dongjin. The japonica rice was grown in controlled chamber conditions with and without P. formosus LWL1 under no stress （NS） and prolonged heat stress （HS） conditions. Endophytic association under NS and HS conditions significantly improved plant growth attributes, such as plant height, fresh weight, dry weight, and chlorophyll content. Furthermore, P. for- mosus LWL1 protected the rice plants from HS compared with controls, indicated by the lower endogenous level of stress-signaling compounds such as abscisic acid （25.71%） and jasmonic acid （34.57%） and the increase in total protein content （18.76%-33.22%）. Such fungal endophytes may be helpful for sustainable crop production under high environmental temperatures.

Would behavioral thermoregulation enable pregnant viviparous tropical lizards to cope with a warmer world?

Sceloporus lizards depend on external heat to achieve their preferred temperature(Tsel)for performing physiological processes.Evidence both in the field and laboratory indicates that pregnant females of this Genus select body temperatures(Tb)lower than 34℃ as higher temperatures may be lethal to embryos.Therefore,thermoregulation is crucial for successful embryo development.Given the increase in global air temperature,it is expected that the first compensatory response of species that inhabit tropical climates will be behavioral thermoregulation.We tested whether viviparous Sceloporus formosus group lizards in the wild exhibited differences in thermoregulatory behavior to achieve the known Tsel for developing embryos regardless of local thermal conditions.We quantified field active body temperature,thermoregulatory behavior mechanisms(time of sighting,microhabitat used and basking time)and available microhabitat thermal conditions(i.e.operative temperature)for 10 lizard species during gestation,distributed along an altitudinal gradient.We applied both conventional and phylogenic analyses to explore whether Tb or behavioral thermoregulation could be regulated in response to different thermal conditions.These species showed no significant differences in field Tb during gestation regardless of local thermal conditions.In contrast,they exhibited significant differences in their behavioral thermoregulation associated with local environmental conditions.Based on these observations,the differences in thermoregulatory behavior identified are interpreted as compensatory adjustments to local thermal conditions.We conclude that these species may deal with higher temperatures predicted for the tropics by modulating their thermoregulatory behavior.