To obtain high yields of winter wheat, it is important to control the contamination crops with weeds. It known that yield losses can be 30% or more due presence segetal vegetation in wheat crops. With intensive technology growing chemical method protection against weeds an extremely element. The paper highlights data on species composition and class agrocenosis. effectiveness herbicides their t...

To determine the effect of salt stress on seed germination of Leymus species, seeds of Leymus racemosus (Lam.) Tzvel., Leymus angustus (Trin.) Pilger, Leymus multicaulis (Kar. et Kir.) Tzvel., Leymus duthiei (Stapf) Y. H. Zhou et H. Q. Zhang and Leymus secalinus (Georgi) Tzvel. were treated with NaCl solutions of different concentration: 0 mmol/L, 100 mmol/L, 200 mmol/L, 300 mmol/L, 400 mmol/L ...

A prominent goal of invasive plant management is to prevent or reduce the spread of invasive species into uninvaded landscapes and regions. Monitoring and control efforts often rely on scientific knowledge of suitable habitat for the invasive species. However, rising temperatures and altered precipitation projected with climate change are likely to shift the geographic range of that suitable ha...

Purpose – This paper aims to present and discuss cheat sites and cheating practices associated with Whyville.net, a virtual world with over 1.7 million registered players aged eight to 16 that includes game and science activities. The goal is to examine how the development of cheats can present learning opportunities for players and designers alike. Design/methodology/approach – The types of ch...

Subsequent chapters in this volume deal with populations as dynamic entities in time and space. Populations are, of course, made up of individuals, and the parameters which characterize aggregate behavior—population growth rate and so on— ultimately derive from the behavioral ecology and life-history strategies of these constituent individuals. In evolutionary terms, the properties of populatio...

A former lectotype for Bromus cincinnatus Ten. (Poaceae) has been superseded, as it is in serious conflict with the protologue. Another element of protologue designated effective lectotype. The new identified coespecific intermedius Guss., a Mediterranean species L. subg. Bromus. combination Helictochloa panormitana (Lojac.) Romero Zarco proposed originally described Avena australis Parl., nom....

negatively affected by disturbance. meadow barley (Hordeum brachyantherum Nevski) (Hickman 1993). Purple needlegrass, blue wildrye, bluegrass and California melic are droughttolerant species that typically occupy well-drained upland sites. In contrast, creeping wildrye and meadow barley are less drought-tolerant and typically grow in the moist soils of seeps, streams and wetland margins (Walker...

UNLABELLED PREMISE OF THE STUDY Phenolic compounds exuded by roots have been implicated in allelopathic interactions among plants. Root enzymes that destroy phenolics may protect plants against allelopathic inhibition and thus may aid in invasiveness. Phenolic-degrading enzymes are chiefly found in aboveground plant parts, but have also been previously reported in root tissues where the enzy...