جستجوی مقالات مرتبط با کلیدواژه "دگرآسیبی" در نشریات گروه "منابع طبیعی"

In order to investigation the effects of different concentrations of leaf aqueous extracts of walnut on seed germination and seedling growth of barley, arugula and corn, a laboratory experiment were conducted in the Faculty of Agronomy, Islamic Azad University of Isfahan, in 2013. In this experiment, walnut leaf extract including control (distilled water), 25, 50, 75 and 100% were studied to determine juglone sensitivity in three species based on completely randomized design (CRD) with four replications. Chromatography analysis showed that a highest rate of juglone was observed on walnut leaves in August. Increasing concentration of leaf extract lead to continuously decrease in germination percentage and germination rate, root and shoot length and seedling dry weight. Germination percentage of corn and arugula seeds on primary growth stage showed resistant to walnut allelopathy. The lowest germination percentage was observed on barley in %100 leaf aqueous extracts of walnut. Corn and arugula were more sensitive to walnut extracts than barley seeds, however, root and shoot dry weight in barley had no significantly different between treatments. The aqueous extract of walnut did not have a significant effect on germination components of barley, corn and arugula, so that corn and arugula in the early stages of germination and barley in seedling growth showed strong resistance. The insensitivity of the studied species showed that the aqueous extract of Iranian walnut leaves is a strong substance in controlling weeds of these species towards sustainable agriculture.

Germination and seedling growth is one of the important processes that affect different plants allelopathic properties.Leaving crop residue on the soil surface can be caused production of phtochemicals that prevent from crop growth. In order to study the allelopathic effect of the Peganum harmalaon seed germination and seedling growth characteristicsof four wheat cultivar included of Morvarid, Kuhdasht, Gonbad and lin17 an experiment was conducted by a factorial Randomized complete design with four replicationsin the laboratory of Agricultural Faculty of Gonbad university. The treatments were included 4 concentrations harmal extract (0, 25, 50, and 75 percent) and four wheat cultivar's (Morvarid, Kuhdasht, Gonbad and lin17). The analysis of variance showed that the effect of cultivar, harmala extract concentration and interaction effects treatments were significant at 1% probability on all studied traits to exception seedling dry weight. Increasing harmala extract concentration had negative effect on all studied traits in all wheat cultivars.Means comparison in control levels showed that germination rate, beginning and end effective germination, germination percentage were not significantly difference among cultivars but Gonbad cultivar had less uniformity germination than other cultivars. Gonbadand Morvarid cultivars with 37% and 85% of germination had the highest and the lowest germination respectively.According to the results in control treatment, Morvarid andGonbad had the most seedling length, seedling vigor index and coefficient Allometry, butin 75% harmala extract concentration, Morvarid and Kouhdasht cultivars were better than others cultivars.

Due toproblems arising from the use of natural methods acceptable herbicides for weed control has been identified. Allelopathyby releasing allochimical be one way to control weeds is worthwhile.  In order to show the effects of aqueous extracts of Tarrgon  and Savory on germination and growth of weeds Savory  Oats seed  in greenhouse, in College of Agricultural of azad university of shiraz, shiraz, Fars provenice, Iran wasconducted.experimentin a randomized complete block design with three replications and three factors were performed(The first factorin both savory and tarragon plant surface and the second factor and the third factor 4 levels in both leaf and stem). 7, 9, 11 and 13 days after sowing germinated seeds counted and the various parameters, was measured. resultsindicated that theuse ofsavory andtarragonleaves andstems of plantsmay reducethegermination andearly growthtraitsandoatsvehiclehas affected.SavoryTarragonplantdebriseffectwas moreandmoretraitshas reducedby 6%. A recentevaluationofallelopathiceffectsonweeds,crop residues, andothermaterialstoreduce reliance onherbicidesisnormaldamage. Future studies of this plant can be used to control weeds, oats .