Root-zone temperature and salinity: Interacting effects on tillering,growth and element concentration in barley

The effects of root-zone salinity (0, 30, and 60 mmol L^–1 of NaCl) and root-zone temperature (10, 15, 20, and 25°C) and their interactions on the number of tillers, total dry matter production, and the concentration of nutrients in the roots and tops of barley (Hordeum vulgare L.) were studied. Experiments were conducted in growth chambers (day/night photoperiod of 16/8 h and constant air temperature of 20°C) and under water-culture conditions. Salinity and root temperature affected all the parameters tested. Interactions between salinity and temperature were significant (p<0.05) for the number of tillers, growth of tops and roots, and the concentration of Na, K, P in the tops and the concentration of P in the roots. Maximum number of tillers and the highest dry matter were produced when the root temperature was at the intermediate levels of 15 to 20°C. Effect of salinity on most parameters tested strongly depended on the prevailing root temperature. For example, at root temperature of 10°C addition of 30 mmol L^–1 NaCl to the nutrient solution stimulated the growth of barley roots; at root temperature of 25°C, however, the same NaCl concentration inhibited the root growth. At 60 mmol L^–1, root and shoot growth were maximum when root temperature was kept at the intermediate level of 15°C; most inhibition of salinity occurred at both low (10°C) and high (25°C) root temperatures. As the root temperature was raised from 10 to 25°C, the concentration of Na generally decreased in the tops and increased in the roots. At a given Na concentration in the tops or in the roots, respective growth of tops or roots was much less inhibited if the roots were grown at 15–20°C. It is concluded that the tolerance of barley plant to NaCl salinity of the rooting media appears to be altered by the root temperature and is highest if the root temperature is kept at 15 to 20°C.     

Postnatal growth in the Long-fingered Bat,Miniopterus schreibersii pallidus,in Iran (Chiroptera: Miniopteridae)

This study describes the postnatal development of body mass, forearm length and epiphyseal phalangeal gap in a free ranging population of the Long-fingered Bat, Miniopterus schreibersii pallidus Thomas, 1907, in a maternity roost in the Mahidasht cave in western Iran. The pups at birth had a mean body mass of 3.74?±?0.09 g and forearm length of 24.3?±?0.31mm. The length of forearm and body mass increased linearly during first two weeks, and thereafter maintained an apparent stability. The epiphyseal gap of the fourth metacarpal phalangeal joint increased until the thirteenth day, then decreased linearly until the 70th day and thereafter fused. The rate of body mass gain and forearm growth during the first 13 days was 0.54 g/day and 1.39 mm/day, respectively. Initiation of flight occurred three weeks after birth. A method of estimating age was derived from the values of the forearm length and the total gap of the fourth metacarpal-phalangeal joint during the pre-flight and post-flight periods.     

Salicylic acid improves podophyllotoxin production in cell cultures of Linum album by increasing the expression of genes related with its biosynthesis

Treatment of Linum album cell cultures with 10 μM salicylic acid (SA) for 3 days improved podophyllotoxin (PTOX) production up to 333 μg/g dry weight (DW): over three times that of the control cultures. qPCR analyses showed that in SA-treated cells, the expression of the genes coding for phenylalanine ammonia-lyase (PAL), cinnamoyl-CoA reductase (CCR) and cinnamyl-alcohol dehydrogenase (CAD), all involved in the first steps of PTOX biosynthesis, also increased reaching a peak 8–12 h after the treatment. Expression of the pinoresinol-lariciresinol reductase gene (PLR), which is involved in one of the last biosynthetic steps, was not affected by SA. The selective action of SA on these genes can be applied to control the biotechnological production of this anticancer agent.     

Evaluation of the Trophic Diatom Index for assessing water quality in River Gharasou,western Iran

Water quality, diatom species composition and biomass estimates were performed in the Gharasou River in western Iran. Five sites along the River Gharasou were sampled every month from April to September 2005. Physical and chemical factors (pH, NO₃–N, PO₄–P, dissolved oxygen, total suspend solids, total dissolved solids, conductivity, turbidity, chemical oxygen demand and biological oxygen demand) were measured along with biological properties of the periphyton including biomass, ash-free dry mass, chlorophyll-a concentration and the taxonomic composition diatom assemblages. Information from the diatom assemblage was used to calculate the Trophic Diatom Index and biovolume. The TDI was significantly correlated with measures of human disturbance at the sites (e.g. PO₄–P, NO₃–N and dissolved oxygen) as well as to biomass measures (chlorophyll a, ash-free dry mass and biovolume). The sensitivity of the TDI and its component metrics to environmental stressors supports the use of this index for monitoring ecological conditions in streams in Iran and to aid diagnosis of the cause of their impairment. Handling editor: L. Naselli-Flores     

Effects of Increased Salinity on Growth,Development and Survival in Early Life Stages of the Green Toad Bufotes variabilis (Anura: Bufonidae)

This study examined the effects of increased salinity on growth,development and survival of the Green toad,Bufotes variabilis during embryonic,hatching and early larval periods.Eggs from a single cohort of B.variabilis were subjected to acute and chronic toxicity tests for water salinity ranging from 0.20 to 10 g of salt per liter.Results obtained from this study showed that salinity over 3.70 g/l increased embryonic mortality and reduced percentage of hatching and survival rate of larvae.As larvae tolerated salinity 0.20 to 3.70 g/l with highest survival,but salinity of 10 g/l caused mortality of all individuals within 12 h,7.70–8.70(g/l)within 4.5 days,5.70–6.70 g/l within 10 days and 4.70(g/l)were tolerated within 14 days.Salinity less than 0.70 g/l did not affect survival and hatching success of the embryos.After a 3-week experiment,size of larvae exposed to salinities over 0.70 g/l was lower compared to larvae reared at lower salinity levels.Meanwhile increases in salinity more than 3.70 g/l caused extension in the hatching period.Larvae reared at salinity of 3.70 to 4.70 g/l had morphological abnormalities,such as distortion of tail.     

Ontogenetic changes in spot configuration (numbers,circularity, size and asymmetry) and lateral line in Neurergus microspilotus (Caudata: Salamandridae)

Coloration in three of four species of the genus Neurergus including N. microspilotus is characterized by the presence of yellow spots on a dark skin, but there is no available information about changes in spot configuration, speed of development and degree of association between melanophore‐free region and the lateral line. In this study, spot numbers, spot circularity, spot size and spot asymmetry were studied during larval to adult growth in N. microspilotus during July 2012 to June 2015. The mean numbers of spots increased during the late larval stage till postmetamorphic period from 13.33 ± 3.77 to 22.53 ± 4.09 and reached 42.62 ± 4.06 in adults. At the same time, the extent of spots gradually decreased in size from 5.80 ± 1.00 to 3.57 ± 0.97 mm² and reached 3.55 ± 1.42 mm² in adults, but the spot circularity increased from 0.48 ± 0.23 to 0.78 ± 0.49 and reached 0.80 ± 0.15 in adults. In adults, the numbers, circularity, size and asymmetry of spots remain stable with little but non‐significant changes during the study period. Histological study shows that formation of a melanophore‐free region correlates with the development of the lateral line receptors. This study demonstrates that the effects of lateral line on chromatophores persist through middle larval stages but diminish as metamorphosis completes.     

Variation in food availability mediate the impact of density on cannibalism,growth, and survival in larval yellow spotted mountain newts (Neurergus microspilotus): Implications for captive breeding programs

In this study, we examined cannibalistic behavior, growth, metamorphosis, and survival in larval and post‐metamorph endangered yellow spotted mountain newts Neurergus microspilotus hatched and reared in a captive breeding facility. We designed a 2 × 2 factorial experiment, crossing two levels of food with two levels of density including high food/high density, high food/low density, low food/high density, and low food/low density. The level of cannibalistic behavior (including the loss of fore and hind limbs, missing toes, tail, gills, body damage, and whole body consumption) changed as the larvae grew, from a low level during the first 4 weeks, peaking from weeks 7 to 12, and then dropped during weeks 14–52. Both food level and density had a significant effect on cannibalism. The highest frequency of cannibalism was recorded for larvae reared in the low food/high density and lowest in high food/low density treatments. Growth, percent of larval metamorphosed, and survival were all highest in the high food/low density and lowest in low food/high density treatment. Food level had a significant effect on growth, metamorphosis, and survival. However, the two levels of density did not influence growth and metamorphosis but showed a significant effect on survival. Similarly, combined effects of food level and density showed significant effects on growth, metamorphosis, and survival over time. Information obtained from current experiment could improve productivity of captive breeding facilities to ensure the release of adequate numbers of individuals for reintroduction programs. Zoo Biol. 35:513–521, 2016. © 2016 The Authors. Zoo Biology published by Wiley Periodicals, Inc.     

Effect of exposure to extremely low electro-magnetic field during prenatal period on mice spleen

Total body weight of newborns, the volume of spleen, and the number of megakaryocytes decreased following the exposure to ELF-MF (6 x 10(-3) T and 50 Hz) at 1-5, 6-10, 11-15, and 16-20 days of pregnancy of mice. The complete period of gestation was sensitive to ELF-MF exposure; the initial days were more prone to exposure. The results suggest that the use of ELF-MF producing instruments should be limited during gestation.     

Significant enhancement of lignan accumulation in hairy root cultures of Linum album using biotic elicitors

Linum album has been shown to accumulate some lignans with antiviral and anticancer properties such as podophyllotoxin (PTOX) and 6-methoxy podophyllotoxin (MPTOX). In this research, we examined the effects of fungal elicitors on the production of lignans in L. album hairy root cultures. The biosynthesis of lignans was differentially affected by fungal elicitors. Fusarium graminearum extract induced the highest increase of PTOX, 190 μg g^?1 dry weight (DW), and lariciresinol, 260 μg g^?1 DW, which was two-fold and three-fold greater than the untreated control, respectively, while Trichoderma viride extract enhanced the accumulation of MPTOX, instead of PTOX, up to 160 µg g^?1 DW, which was 2.4-fold greater than the control. The enhancing effects of fungal elicitors on lignans production was correlated with the increased expression of some key genes involved in the biosynthesis of these compounds, phenylalanine ammonia-lyase, cinnamoyl-CoA reductase, cinnamyl-alcohol dehydrogenase and pinoresinol-lariciresinol reductase.     

Vesiculated Hairs: A Mechanism for Salt Tolerance in Atriplex halimus L

The concentration of salts in the vesiculated hairs of Atriplex halimus L. was measured and was remarkably higher than that of the leaf sap and xylem exudate. In spite of their unusually high salt content, these hairs when immersed seemed unable to absorb water, in apparent contradiction to the previously held hypothesis that vesiculated hairs make it possible for such plants to absorb water from the atmosphere. Although growing the plants under saline conditions increased the salt content of the hairs from 2.3 m Na+K to 11.6 m, salt content of the expressed leaf sap from young leaves did not change significantly. This observation indicates that in A. halimus the vesiculated hairs play a significant role in removing salt from the remainder of the leaf and preventing the accumulation of toxic salts in the parenchyma and vascular tissues. Thus, a nearly constant salt content is maintained in leaf cells other than the hairs.