background: garlic is a valuable medicinal plant with variability in desirable morphological and physiological characteristics. the analysis of genetic diversity plays an important role in breeding programs. the rapd technique could be very effective in detecting genetic variation in garlic.  objective: the objective of the present work was to detect molecular polymorphism among iranian garlic ...

production of halophyte plants with saline water and soil and feeding them to livestock is one of the most sustainable methods of conservation in desert ecosystem regions. kochia is a high salt resistant plant that can widely use as forage for livestock in arid ecosystems with lack of appropriate water and soil resources. in order to investigate potential of forage production of five different ...

rapid exploratory field survey, to identify indigenous chicken ecotypes was conducted in north gondar zone of ethiopia. chicken ecotypes including necked neck, gasgie and gugut from quara, alefa and tache armacheho districts were identified, respectively. morphological variations among the three study populations and nine measurable traits were evaluated. general linear model, canonical discrim...

Hypothesis: Seasonal variation in availability of resources maintains co-existence between different ecological types due to frequency-dependent interactions. Organism: Escherichia coli. Methods: When populations containing two ecotypes of E. coli that evolved from a common ancestor under sympatric conditions grow in batch culture on a mixture of glucose and acetate, they first use up the avail...

Through microscopic analysis of veins and assessment of light- and CO2-saturated rates of photosynthetic oxygen evolution, we investigated the relationship between minor loading vein anatomy and photosynthesis of mature leaves in three ecotypes of Arabidopsis thaliana grown under four different combinations of temperature and photon flux density (PFD). All three ecotypes exhibited greater numbe...

Specialization in plant host-symbiont-soil interactions may help mediate plant adaptation to edaphic stress. Our previous field study showed ecological evidence for host-symbiont specificity between serpentine and non-serpentine adapted ecotypes of Collinsia sparsiflora and arbuscular mycorrrhizal fungi (AMF). To test for adapted plant ecotype-AMF specificity between C. sparsiflora ecotypes and...

Killer whales (Orcinus orca) currently comprise a single, cosmopolitan species with a diverse diet. However, studies over the last 30 yr have revealed populations of sympatric "ecotypes" with discrete prey preferences, morphology, and behaviors. Although these ecotypes avoid social interactions and are not known to interbreed, genetic studies to date have found extremely low levels of diversity...

Bacteria are profoundly different from eukaryotes in their patterns of genetic exchange. Nevertheless, ecological diversity is organized in the same way across all of life: individual organisms fall into more less discrete clusters on the basis of their phenotypic, ecological, and DNA sequence characteristics. Each sequence cluster in the bacterial world appears to correspond to an "ecotype," d...

Previous analysis of the PAI tryptophan biosynthetic gene family in Arabidopsis thaliana revealed that the Wassilewskija (WS) ecotype has four PAI genes at three unlinked sites: a tail-to-tail inverted repeat at one locus (PAI1-PAI4) plus singlet genes at two other loci (PAI2 and PAI3). The four WS PAI genes are densely cytosine methylated over their regions of DNA identity. In contrast, the Co...

Forces driving the evolution of reproductive isolation among natural populations, as well as the mechanisms involved to maintain it, are still poorly understood. Because sympatric ¢sh ecotypes mainly di¡er in phenotypic traits associated with occupying distinct trophic niches, it is generally believed that reproductive isolation is mainly driven by ecological divergent selection, excluding geno...