Morpho-Physiological and Biochemical Characterization of Soybean-Associated Rhizobia and Effect of Their Liquid Inoculant Formulation on Nodulation of Host Plants in the Cameroon Cotton Fields Zone

The aim of this research was to assess the diversity of the Cameroon cotton zone in soybean associated rhizobia in order to formulate the most efficient elite inoculant to boost both the cotton and soybean production. Therefore, soybean associated rhizobia were isolated and characterized morphologically, physiologically and biochemically on YEMA culture media. For each of the two soybean varieties (Houla1 and TGX1910 14F) used, the trials were laid out in two IRAD-fields of North Cameroon (Sanguere-Paul) and Far-North (Soukoundou) respectively, under a complete randomized complete block design, the isolate formulations representing the treatments. The six isolated strains (IS1, IS2, IS3, IS4, IS5, IS6) from which seven liquid inoculant were formulated were revealed to belong to the same slow growing group of rhizobia, with a high level of tolerance to temperature, pH, and salinity, with optimum growth at respectively 28˚C, pH (7 - 9), salt (1% - 5%). Not surprisingly, root nodules were formed by both inoculated and uninoculated soybean plants. However, the most efficient soybean-rhizobia symbiosis for nodulations were isolate IS6 associated to TGX1910 14F variety, and isolate IS5 associated to Houla1variety at Sanguere-Paul. Whereas isolate M was associated to TGX1910 14F variety, Houla 1 variety had affinity with native rhizobia isolates at Soukoundou. The present results suggest the adaptability of rhizobia isolates to a particular soybean variety at a particular cotton fields zone. These findings should be taken into consideration for commercial inoculant formulation.

Effect of Scurrula atropurpurea on blood pressure and angiotensin Ⅱ of deoxycorticosterone acetate-salt hypertensive rats

OBJECTIVE To investigate the effect of methanolic extract of Scurrula atropurpurea on systolic blood pressure and serum angiotensinⅡ concentration in deoxycorticosterone acetate-salt(DOCA-salt)hypertensive rats.METHODS Twenty-five male Wistar rats were divided into normal control group and four hypertensive groups by DOCA-salt for 6 weeks.Further,three hypertensive groups were orally administered with methanolic extract of Scurrula atropurpurea at a doses of 50,100 and 200mg·kg-1,respectively for 6 weeks and one hypertensive group without extract as positive control.At the end of research systolic blood pressure were measured by tail cuff methods.Serum angiotensinⅡ were measured by ELISA.RESULTS The systolic blood pressure increased significantly in the positive control hypertensive group compared to the normal control group(P<0.05).Administration of methanolic extract of Scurrula atropurpurea 50,100 and 200mg·kg-1 significantly decreased systolic blood pressure,respectively compared to the positive control hypertensive group(P<0.05).There was no different angiotensinⅡ consentration between positive control hypertensive group and normal group,while methanolic extract of Scurrula atropurpurea 50mg·kg-1 caused decreased angiotensinⅡ conscentration significantly compared to positive control hypertensive group(P<0.05).CONCLUSION Methanolic extract of Scurrula atropurpurea produced antihypertensive effect and decreasing angiotensinⅡ concentration at 50mg·kg-1 in hypertensive rat.Beside this,the concentration of angiotensinⅡ couldn′t increase in DOCA-salt hypertensive rats.

Resistance to the Whitefly Aleurotrachelus socialis(Hemiptera:Aleyrodidae) and SSR Marker Identification in Advanced Populations of the Hybrid Manihot esculenta subsp.Manihot flabellifolia

Genes resistant to Aleurotrachelus socialis were transferred to the F 1 from the interspecific hybrid wild species of Manihot flabellifolia to M.esculenta and two advanced generations of backcrosses（BC 1 and BC 2）.We characterized the resistance of A.socialis transferred to BC 2 parents（CW67-160,CW67-130,CW67-44）,MTAI-8（BC 1）,resistant（CMB9B-73） and susceptible（CMB9B-104） genotypes from contrasting pools,and resistant（MEcu-72） and susceptible（CMC-40） genotypes.Whitefly demography and biology were evaluated.SSR molecular markers associated with a phenotypic response of plant resistance were detected in segregating populations（BC 2）.Results showed that although female survival time was similar on all hosts,the lowest averages of longevity,fecundity and oviposition rate were observed in the resistant control MEcu- 72,only being significantly similar to the parent CW67-130.When the BC 1 and BC 2 populations were compared,it was found that A.socialis fecundity was eight times lower on CMB9B-73 progeny than on CW67-130,expressing the highest levels of resistance to the whitefly.Ten genotypes of CMB9A and CMB9B family had the best segregation.A total of 486 microsatellite primers were evaluated using bulked segregant analysis（BSA）,11 showed polymorphism between the contrasting pools and only one showed significant differences between resistant and susceptible individuals.In conclusion,fecundity was the parameter that impacted most on the intrinsic rate of A.socialis population growth.

Demographic Expansion and Contraction in a Neotropical Fish during the Late Pleistocene-Holocene

Demographic changes during the late Pleistocene-Holocene left signatures in the DNA of contemporary populations. These signatures reveal demographic phenomena like the increase or decrease in effective population size. In this paper we searched for signatures of demographic change in the DNA of the Neotropical freshwater fish Poecilia vivipara. Also, we investigated whether demographic changes are correlated with palaeoclimatic events of the late Pleistocene-Holocene, in particular, if changes in effective population size are correlated with expansion and contraction of available habitats, induced by global ice-volume changes and sea-level fluctuations. We used Bayesian Skyline Plot (BSP) analysis with sequences from the mitochondrial gene cytochrome b to estimate the ancestral demography of the Neotropical freshwater fish P. vivipara. To test the assumptions of neutrality and absence of population structure we used Tajima’s D and Spatial Analysis of Molecular Variance (SAMOVA), respectively. Effective population size of P. vivipara remained stable until 75,000 years ago, increased by 10-fold reaching a maximum at approximately 25,000 years ago, then suddenly declined at the Pleistocene-Holocene boundary. Variation in effective population size in P. vivipara correlates with expansion and contraction of habitats induced by sea-level fluctuations, caused by the advance and retreat of ice sheets during the Last Glacial Maximum (LGM).

伊朗青蜂科、锤角细蜂科、螯蜂科、环腹蜂科和细蜂科(膜翅目)的区系研究（英文）

报道了伊朗膜翅目Hymenoptera 5个科,青蜂科Chrysididae、锤角细蜂科Diapriidae、螯蜂科Dryinidae、环腹蜂科Figitidae和细蜂科Proctotrupidae的区系调查。采集和鉴定了青蜂科的6属12种、锤角细蜂科的4属5种、螯蜂科的5属7种、环腹蜂科的4属5种和细蜂科的3属3种。

Bio-fuel Production From Carbondioxide Gas Using S. elongatus PCC 7942 from Cyanobacteria

The aim of this study,is 1-butanol production using CO2 with S.elongatus PCC 7942 culture.The yields of 1-butanolproduced/CO2utilized have been calculated.The maximum concentration of produced 1-butanol is 35.37 mg/L and 1-butanolproduced/CO2utilized efficiency is 92.4.The optimum operational conditions were 30°C temperature,60 W intensity of light,pH=7.1,120 mV redox potential,0.083 m^3/sn flow rate with CO2 and 0.5 mg/l dissolved O2 concentration.Among the enzymes on the metabolic trail of the production of 1-butanol via using S.elongatus PCC 7942 cyanobacteria.At maximum yield;the measured concentrations are 0.016μg/ml for hbd;0.0022μg/ml for Ter and 0.0048μg/ml for AdhE2.The cost analyses necessary for 1-butanol production has been done and the cost of 1 liter 1-butanol has been determined as 1.31 TL/L.