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The ultrastructure, neuroanatomy and central projection patterns, including the intercellular connections of the statocyst hair cells of the pond snail, Lymnaea stagnalis, were studied, applying different intra- and extracellular cellular staining techniques combined with correlative light- and electron microscopy. Based on the ultrastructure different hair cells could be distinguished according to their vesicle and granule content, meanwhile the general organization of the sensory neurons was rather uniform, showing clearly separated perinuclear and “vesicular” cytoplasmic regions. Following intra- and extracellular labeling with fluorescence dyes or HRP a typical, local arborization of the hair cells was demonstrated in the cerebral ganglion neuropil, indicating a limited input-output system connected to the process of gravireception. Correlative light- and electron microscopy of HRP-labeled hair cells revealed both axo-somatic and axo-axonic output contacts of hair cell varicosities, and input on sensory axons located far from the terminal arborizations. Our findings suggest (i) a versatile ultrastructural background of hair cells corresponding possibly to processing different gravireceptive information, and (ii) the synaptic (or non-synaptic) influence of gravireception at different anatomical (terminal, axonal and cell body) levels when processed centrally. The results may also serve as a functional morphological background for previously obtained physiological and behavioral observations.
higher elevation to find box tree reservoirs. Acknowledgments We thank Iranian Research Institute of Plant Protection and Agricultural Research, Education and Extension Organization of Iran for support. References Ahangaran , Y. ( 2016 ). The first
We examined the composition and spatial structure of the understorey vegetation at two sites with different fire histories in a mature Pinus sylvestris L. forest in eastern Finland. The entire study area had regenerated after a fire in the early 19thcentury. Besides, a part of the area was subsequently hit by a surface fire in 1906, which divided the study area into two parts. Vegetation and environmental variables measured from the these two parts, the 1800+ burn site and the 1906 burn site, have considerably different spatial pattern. Deciduous shrubs and ground layer, consisting primarily of bryophytes, had a more distinct patch structure at the 1800+ burn site than at the 1906 burn site, while with lichens the situation was the reverse. Cover of the field layer, dominated by evergreen shrubs, was significantly higher at the 1800+ burn site than at the 1906 burn site. At both sites, the spatial pattern of plant functional types was obviously strongly regulated by the spatial influence of living trees. Gradual formation of strong clonal patch structures of V. myrtillus, V. vitis-idaea and mosses, seems to be another important process affecting the properties of the understorey vegetation. The post-fire recovery of the understorey community was slow: in the 1906 burn site, the community composition and spatial structure were still in transition after almost 90 years since the last fire.
30 Llinás, R., Hillman, D. E. (1969) Physiological and morphological organisation of the cerebellar circuits in various vertebrates. In: Llinás, R. (ed.), Neurobiology of Cerebellar
, 3 ]. Guidelines recommended by the World Health Organization (WHO) to diagnose, treat, and prevent TB have been implemented in Côte d'Ivoire since 1995 [ 4 – 6 ]. There were an estimated 36,000 new cases of TB in 2016 [ 7 ]. The main method
Successful production and development of stable and adaptable cultivars only depend on the positive results achieved from the interaction between genotype and environment that consequently has significant effect on breeding strategies. The objectives of this study were to evaluate genotype by environment interactions for grain yield in barley advanced lines and to determine their stability and general adaptability. For these purposes, 18 advanced lines along with two local cultivars were evaluated at five locations (Gachsaran, Lorestan, Ilam, Moghan and Gonbad) during three consecutive years (2012–2015). The results of the AMMI analysis indicated that main effects due to genotype (G), environment (E) and GE interaction as well as four interaction principal component axes were significant, representing differential responses of the lines to the environments and the need for stability analysis. According to AMMI stability parameters, lines G5 and G7 were the most stable lines across environments. Biplot analysis determined two barley mega-environments in Iran. The first mega-environment contained of Ilam and Gonbad locations, where the recommended G13, G19 and G1 produced the highest yields. The second mega-environment comprised of Lorestan, Gachsarn and Moghan locations, where G2, G9, G5 and G7 were the best adapted lines. Our results revealed that lines G5, G7, G9 and G17 are suggested for further inclusion in the breeding program due to its high grain yield, and among them G5 recommended as the most stable lines for variable semi-warm and warm environments. In addition, our results indicated the efficiency of AMMI and GGE biplot techniques for selecting genotypes that are stable, high yielding, and responsive.
Drought is the major cause of durum wheat yield losses in the Mediterranean and many other regions where the crop is not normally irrigated. Over three years (2010–13), 24 durum wheat genotypes representing diverse genetic materials were tested under drought and irrigated conditions. The main objectives were to assess the degree of genotypic variation for drought tolerance, characterize genotypic differences in response to drought, and identify sources of germplasm with greater drought tolerance than old and new cultivars. The percent reduction in average grain yield under drought conditions as compared to irrigated conditions was maximum (69%) during 2012–13, followed by 2010–2011 (33%) and 2011–2012 (15%). The average yields of genotypes under drought conditions differed significantly, which ranged from 1174 (correspond to old variety) to 2086 kg/ha (correspond to breeding line G2). The maximin-minimax approach, yield tolerance index (YTI) and three-dimensional (3-D) plot were used to classify genotypes for drought tolerance and yield productivity. Based on the results, two genotypes were identified as resistant and high yielding (G3 and G20), and eight genotypes (G2, G22, G8, G11, G15, G1, G9 and G5) were found to be high yielding and tolerant to drought conditions. Among the methods, the maximin–minimax approach appears to be more useful in identifying high yielding and drought tolerant genotypes as it seeks to minimize percentage yield loss while maximizing yield potential. In conclusion, considerable variability in yield and drought tolerance was observed for the durum wheat genotypes, which could be exploited at improving drought tolerance in durum wheat breeding program.
. Temporal variability in the spatial and environmental determinants of functional metacommunity organization — stream fish in a human-modified landscape . Freshwater Biol. 57 : 1914 – 1928
The combining ability of four tomato genotypes (Lycopersicon esculentum Mill.) for salt tolerance was determined by investigating the progeny from a 4 × 4 diallel cross. Sixteen progenies (F1s, selfs and reciprocals) were evaluated at three levels of salinity (0%, 1.0%, 1.5%) in a complete block design with four replications under greenhouse conditions. The analysis of the genetic component revealed that the mode of inheritance of salt tolerance appeared to be different to that of plant characters and salinity levels as measured by plant height and fruit yield components. However, the fruit count was consistently controlled by additive gene effects. The specific crosses Moneymaker (MM) × Red Alert (RA) and Ailsa Craig (AC) × Gardener's Delight (GD) produced the highest yield. The small-fruited parents, Red Alert and Gardener's Delight, had higher general combining ability value for salt tolerance than the large-fruited, Ailsa Craig and Moneymaker, for fruit yield components. RA and GD were superior parents in transmitting salt tolerance. The study revealed that plant selection could be used to improve varietal performance for salt tolerance. It is also suggested that the potential variation in commercial cultivars could be exploited to improve adaptability to more saline growing conditions till resistant cultivars are developed through crosses with the wild species or genetic transformation with optimum management practices.
