BACKGROUND HIV-1 drug resistance can be measured with phenotypic drug-resistance tests. However, the output of these tests, the resistance factor (RF), requires interpretation with respect to the in vivo activity of the tested variant. Specifically, the dynamic range of the RF for each drug has to be divided into a suitable number of clinically meaningful intervals. METHODS We calculated a su...

Oscillations in stomatal resistance to viscous air flow have been recorded in the juvenile and adult sclerophylls of Eucalyptus umbra R. T. Baker, in both controlled and natural environments. Under constant illumination, temperature, and humidity, irregular oscillations in stomatal resistance with a periodicity of approximately 20 to 30 minutes occurred spontaneously, when the soil water potent...

Stagonospora nodorum blotch (SNB) caused by Stagonospora nodorum is a severe disease of wheat (Triticum aestivum) in many areas of the world. S. nodorum affects both seedling and adult plants causing necrosis of leaf and glume tissue, inhibiting photosynthetic capabilities, and reducing grain yield. The aims of this study were to evaluate disease response of 280 doubled haploid (DH) individuals...

the influence of leaf pubescence of three wheat cultivars (pishtaz, ghuds and falat) on preference and biological parameters of sipha maydis (passerini) was investigated under greenhouse conditions (25 ± 2 °c, 70 ± 10% rh and 14: 10 h (l: d) photoperiod). the results showed that pishtaz had a greater density of trichomes compared to the other cultivars. in the preference test with whole plant, ...

Two classes of genes are used for breeding rust resistant wheat. The first class, called R (for resistance) genes, are pathogen race specific in their action, effective at all plant growth stages and probably mostly encode immune receptors of the nucleotide binding leucine rich repeat (NB-LRR) class. The second class is called adult plant resistance genes (APR) because resistance is usually fun...

pollen grains as well as whole plants of four olive (olea europaea l.) cultivars were screened for nacl salinity stress. different vegetative and physiological indexes of the cultivars were analyzed. leaf and root na/k ratio as well as stomatal resistance of plants exposed to salinity proved to be appropriate indexes of whole plant response to salt stress. whereas, in vitro pollen germination p...

the stripe (yellow) rust in wheat is one of the most important plant diseases in iran. since 1993 several epidemics have occurred in iran causing the breakdown of widely util-ized sources of resistance in wheat cultivars. twenty-seven pathotypes were identified during 2003 and 2004 in greenhouse tests. pathotypes 6e6a+, 6e22a+, 6e130a+, 6e134a+, 6e142a+, 6e158a+, 134e130a+ and 134e142a+ were mo...

Plant diseases are a serious threat to crop production. The informed use of naturally occurring disease resistance in plant breeding can greatly contribute to sustainably reduce yield losses caused by plant pathogens. The Ta-Lr34res gene encodes an ABC transporter protein and confers partial, durable, and broad spectrum resistance against several fungal pathogens in wheat. Transgenic barley lin...