The natural occurrence of entomophthoralean fungi pathogenic towards aphids on cereal and potato crops was investigated in the years 2009, 2010, and 2011. Infected aphids were sampled in three bioclimatic zones in Tunisia (Beja, Cap bon, and Kairouan) and fungal species were determined based on morphological characters such as shape, size, and number of nuclei in the primary conidia. Polymerase...

The application of DNA sequencing technology to the study of ancient DNA has enabled the reconstruction of past epidemics from genomes of historically important plant-associated microbes. Recently, the genome sequences of the potato late blight pathogen Phytophthora infestans were analyzed from 19th century herbarium specimens. These herbarium samples originated from infected potatoes collected...

In plants, it is possible to induce heritable transcriptional gene silencing (TGS) via RNA-directed DNA methylation (RdDM) using artificially synthesized small RNA (siRNA) homologous to the 5'-flanking region of the target gene. As the siRNA signal with a specific RNA determinant moves through plasmodesmata and sieve elements, we attempted to induce TGS of a transgene and an endogenous gene of ...

The paper addresses environmental concerns raised for transgenic potatoes with increased resistance to insects or viruses and discusses whether transgenic potato cultivars are different from traditionally bred cultivars. Iftransgenic potatoes are cultivated in regions with interfertile species, gene transfer to wild relatives will occur. This has implications on the potential for increasedfitne...

Sequences obtained from transcriptomes of the lady beetle Coleomegilla maculata were compared to those designed for incorporation into crops. Searches of the transcriptomes identified sequences as the most likely to be closely similar to the sequences described in RNAi plant incorporated products. Some proposed prime RNAi pest management targets were also used to identify predicted orthologs fr...

Sweetpotato (Ipomoea batatas (L.) Lam.) is the third most important root crop in the world, ranking seventh among all crops in global production and fourth in developing countries after rice, wheat, and corn (10). In Africa, sweetpotato plays a vital role in peoples’ ability to sustain their families, especially during periods of hardship. However, sweetpotato plants, like other crops, are sign...

An approach for estimating human exposure to pesticides via consumption of six important food crops is presented that can be used to extend multimedia models applied in health risk and life cycle impact assessment. We first assessed the variation of model output (pesticide residues per kg applied) as a function of model input variables (substance, crop, and environmental properties) including t...

abstract to find out how maize and potato can grow and develop in an intercropping system rather than each grown alone in a sole cropping system the following factorial experiment was performend in the frame-work of a randomized complete block three replications in the experimental farm of the faculty of agriculture, zanjan university in year 2004. different potato to maize ratios of (1:0), i.e...

Hydrologic climate change modelling is hampered by climate-dependent model parameterizations. To reduce this dependency, we extended the regional hydrologic modelling framework SIMGRO to host a two-way coupling between the soil moisture model MetaSWAP and the crop growth simulation model WOFOST, accounting for ecohydrologic feedbacks in terms of radiation fraction that reaches the soil, crop co...

Transgenic crops able to tolerate environmental stress are being developed throughout the world. However, little data is available on the impact of environmental stress-tolerant transgenic crops on soil microorganisms and biochemistry. Recently developed transgenic potato plants carrying an environmental stress-related gene, DREB1A, with a stress-inducible promoter, are being evaluated for grow...