The ecoresponsive genome of Daphnia pulex

We describe the draft genome of the microcrustacean Daphnia pulex, which is only 200 megabases and contains at least 30,907 genes. The high gene count is a consequence of an elevated rate of gene duplication resulting in tandem gene clusters. More than a third of Daphnia's genes have no detectable homologs in any other available proteome, and the most amplified gene families are specific to the Daphnia lineage. The coexpansion of gene families interacting within metabolic pathways suggests that the maintenance of duplicated genes is not random, and the analysis of gene expression under different environmental conditions reveals that numerous paralogs acquire divergent expression patterns soon after duplication. Daphnia-specific genes, including many additional loci within sequenced regions that are otherwise devoid of annotations, are the most responsive genes to ecological challenges.     

Lavandula gibsonii: A plant with insectistatic potential

Phytoparasitica - The plantLavandula gibsonii (fam. Lamiaceae) has been found to possess various insectistatic activities against several insect pests. Acetone extracts of the whole plant exhibit...     

An approach to assessment of management impacts on agricultural soil carbon

Agroecosystems contain about 12% of the terrestrial soil C and play an important role in the global C cycle. We describe a project to evaluate the degree to which management practices can affect soil C in agroecosystems. The objectives of the project are to determine if agricultural systems can be managed to conserve and sequester C and thereby reduce the accumulation of CO₂ in the atmosphere, and to provide reference datasets and methodologies for agricultural assessments.     

Relationship of growth parameters and nutrients uptake with canola (Brassica napus L.) yield and yield contribution at different nutrients availability

A field experiment was conducted to evaluate the effect of different nutrients on canola (Brassica napus L.) growth parameters, nutrient uptake and ultimately on seed yield. For this purpose a split plot experimental design, with 10 treatments in 4 replications was carried out in 2004-2005, in silt-clay soil at Baiecola Agricultural Research Station, Mazandaran Iran. Canola seed yield, growth parameters (CGR, LAI, RGR and NAR), dry matter accumulation and HI and nutrient content of the leaf were examined. NPK fertilizers together with S and Zn, singly or in combination were applied. The results showed that at treatments T5 (NP), T8 (NPK), T9 (NPKS) and T10 (NPKZn) the higher seed yield (> 2600 kg ha(-1)) coincided with TDM > 880 g m(-2) the peak CGR > or = 13.9 g m(-2) day(-1) and the maximum LAI > or = 4.1. The higher seed yield at T5, T8, T9 and T10 coincided with higher concentrations of nutrients: N, P, K, S and Zn in leaf at flowering having > or = 3.40%, > or = 0.25%, > or = 1.53%, > or = 110 ppm and > or = 22.7 ppm, indicating substantial levels of translocation of nutrients at various stages of plant growth and higher number of pods per plant (> or = 179). Combined application of NPKZn at T10 resulted in maximum seed yield (3090 kg ha(-1)), coinciding with the maximum number of pods per plant (230), maximum TDM (1043 kg ha(-1)), maximum CGR (20.09 g m(-2) day(-1)) and maximum LAI (4.69).