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Litopenaeus vannamei postlarvae were exposed to 0, 6, 13, and 19 mg/L total ammonia nitrogen (TAN) treatments. After 45 days, shrimp weight and length were lowest under TAN concentrations o...

Plant growth-promoting rhizobacteria containing 1-aminocyclopropane-1-carboxylate (ACC) deaminase enzyme reduce the level of stress, ethylene and stimulate plant growth under various biotic and abiotic stress conditions. The present study aims at characterizing efficient salt-tolerant, ACC deaminase containing Pseudomonas fluorescens strains with plant growth-promoting activity isolated from the rhizosphere of barley plants and evaluating the influence of potent plant growth-promoting rhizobacteria (PGPR) isolates on growth and yield of five barley cultivars under salinity stress. Plant growth and yield in barley cultivars following inoculation with salt-tolerant, ACC deaminase producing PGPR strains under salt stress were quantified. Results indicated that under various levels of salinity (50, 100 and 150 mM NaCl) inoculation with PGPRs had positive impact on growth parameters and yield of barley cultivars including plant height, spike length, weight and number, peduncle length, number of grains per spike, 1000-grain weight and grain yield, comparing to uninoculated control plants under salinity stress. Inoculation of barley cultivars with bacteria ameliorated the negative effects of salinity and resulted in increase in growth and yield. Besides, as the salinity levels increased, growth and yield of barley cultivars decreased; however, cultivars showed different responses to salt stress. This study demonstrates the vital role of rhizobacteria containing ACC deaminase for increasing salt tolerance and consequently improving the growth and yield of barley plants under salinity stress.

The aim of this study was to assess the chronic effects of a bio-pesticide (NeemAzal) on some biochemical parameters of grass carp (Ctenopharyngodon idella) under laboratory conditions. At first, 96 h LC50 of the pesticide was determined using probit analysis software and was found to be 0.73 mg L � 1 of the active ingredient (azadirachtin) of the pesticide. Fresh fish were then divided into three treatments and a control and were exposed to sublethal concentrations (10%, 20% and 30% of the 96 h LC50 value) of the pesticide for a month. The biochemical examination of the blood showed a remarkable decrease in values of protein, albumin, AST, ALT, ALP and LDH (P < 0.05).

Contact: berville@supagro.inra.fr; The genetic base of sunflower elite lines is very narrow, due to many years of selection and breeding. To broaden the genetic diversity of the cultivated sunflower, in 1995 73 wild sunflower populations were crossed with 3 cultivated lines (Testers), and 219 hybrid offspring's were evaluated in the field. GCA and SCA effects were computed suggesting for all traits a genetic potential for improvement through selection. Study of the hybrids revealed that the wild accessions bear different genetic abilities to combine with the testers for traits of morphological architecture, phenology and yield (seed weight and seed oil). The variance due to GCA and SCA showed that gene action was additive for days to flowering, branching and plant height. Genotypes derived from the same geographic origin may have either good or poor general combing ability. The correlation between GCA and per se genotype performance was positive for all traits except for seed oil content. This was the first attempt to evaluate wild-cultivated hybrids in sunflower on a large scale and will be the starting point for the management of hybrid Helianthus annuus populations for breeding. GCA and SCA estimations will facilitate the definition of strategies to manage and exploit the natural diversity for this crop

Contact: berville@supagro.inra.fr; International audience; Seventy-seven wild sunflower accessions from USA were compared in France (Mauguio) for 13 quantitative characters using multivariate methods, including clustering, principal component and canonical discriminate analyzes to assess the patterns of morphological and climatic variation. Geographic and climatic data from their sampled sites such as latitude, longitude, elevation, rain fall, temperature, number of rain fall days, temperature range, and sunniness were also analyzed and we sought for correlations of climatic variables and morphological traits. Climatic data clustered the accessions into four groups. Principal component analysis was used to summarize the characteristic habits of annual wild sunflower sampled sites in terms of geography and climates, thus we characterized the ecogeographical profiles of wild sunflowers. As we studied the traits in a common environment we speculated whether local adaptation patterns are sustained by our data. Indeed traits shared by accessions that belong to climatic clusters are suggested to be due to local adaptation