Environmental stresses are the most important factors that reduce plant growth in stages of development. The presence of aluminum in acidic soils as an environmental stress has an impact on different parts of the plant and reduces root growth, water absorption and nutrients and increases susceptibility to drought.  In order to evaluate the effect of aluminum stress levels on wheat at germinatio...

The numbers of greenbugs, Schizaphis graminum (Rondani), and bird cherry-oat aphids, Rhopalosiphum padi L., per wheat tiller (stem) were estimated in 189 production winter wheat (Triticum aestivum L.) fields located throughout Oklahoma. Taylor's power law regressions were calculated from these data and used to construct fixed precision sequential sampling schemes for each species. An evaluation...

The study object is wheat. Through the observation and analysis on the morphological structure of wheat plant, the concepts of macrostate, substate and microstate are put forward, the wheat growth mechanism model is established, and thus the description and control of wheat morphogenesis process could be realized. Based on the branch structure characteristics of plant, the wheat morphological d...

Albedo is a key component of the atmospheric, climatologic and remote sensing studies by means global warming, energy balance, evapotranspiration, climate models, hydrological cycle etc. For these reasons, accurate determination surface albedo has become more important. In this study, variation measured values winter wheat, barley sunflower cultivars according to phenological stages was investi...

Plant biomass and nitrogen status are important factors to consider when making in-season crop management decisions. Traditional sampling and analysis are time-consuming, labor-intensive and costly. It is desirable to estimate these parameters nondestructively using remote sensing technology. The objective of this study is to evaluate the potential of using an active crop canopy sensor, GreenSe...

The content of metal elements in plant tissues of 10-day wheat seedlings after seed pre-treatment and foliar treatment with non-ionic colloidal solution of metal nanoparticles (Fe, Mn, Cu, Zn) was determined by an atomic absorption spectrometer. It was shown that metal nanoparticles due to their physical properties (nanoscale and uncharged state) were capable of penetrating rapidly into plant c...

the crop simulation models are heuristic tools in order to determine optimal of management strategies and analyzing yield stability in agroecosystems. the objective of this study was to evaluate cropsyst model ability for simulating of development, growth and yield of wheat cultivars from golestan province in response to planting date. the results of model evaluation were acceptable so that, th...