Search

Published After
Published Before

Search Results

  • The influence of nitrogen-fertilizer and harvest time on the productivity of Thymus vulgaris L.
    43-46.
    Views:
    237

    The influence of nitrogen-fertilizer applied in 0, 50, 100 and 150 kg/ha dosages, as well as the time of the harvest carried out in full flowering and early fruit set stages were studied on the herb and essential oil production of garden thyme (Thymus vulgaris L.). The small plot experiment was installed in the Experimental Field of Tarbiat Modarres University near Teheran, under sandy loam soil conditions. On the basis of the results the nitrogen-fertilizer had a significant effect on the dry-matter production of the species: the herb yield, calculated on one hectare, increased from 671.88 kg up to 1021.00 kg value as a result of 150 kg nitrogen dosage. The essential oil yield proved to have a similar tendency because neither the accumulation level of essential oil, nor the ratio of thymol were effected by the nutrient supply. Analyzing the effect of harvest time changes in both dry-mass production and essential oil accumulation were observed. The highest herb yield (1238.20 kg/hectare) was obtained in early fruit set, when about.50 per cent of fruits reached their full size in the inflorescence. The accumulation level of essential oil also reached its maximum at the sane development stage, showing 0.75 per cent value, which is about two fold higher comparing to the accumulation level was measured at the time of full flowering (0.41 %).

  • The effects of foliar nutrition containing various macro and microelements on the growth and development of young grafted walnut (Juglans regia L.) plants
    33-37.
    Views:
    165

    The Stopgril liquido (S), a foliar fertilizer containing nitrogen, calcium and magnesium was used to improve the spring and the summer growth of grafted walnut plants in the second year of cultivation in the nursery. To accomplish early termination of vegetative growth and good lignification, the composed mineral fertilizer Hascon M 10 AD (H) containing phosphorous, potassium and microelements B, Mn and Mo was applied on the same plants. Four treatments (S, H, SH, C) were applied three times in a growing season. Their effects on the height and the basal diameter of the plants in the nursery depended on the starting height of the plants and the time of application. During the first growth period in the orchard, the number of developed buds on the plant, the circumference of the plants and their height were influenced by the treatment in the previous year in the nursery. According to the results obtained through the investigation, three applications of Stopgril + Hascon in the nursery per year can be recommended in order to obtain high enough and well lignified two-year-old grafted walnut plants.

  • Comparison of the biogenic amine content of traditional and bio-wines
    115-118.
    Views:
    136

    There has been a growing tendency in organic farming in recent years, in which organic grape growing and the production of bio­wine are also significant. The literature on bio-wine is rather limited, that is why we consider it really important to contribute to the data. As a result of the special conditions in organic farming we can expect bio-wines to have a different composition of nitrogen compounds from that of traditional wines. Biogenic amines could thus specially characterize bio-wines. In our research we compared the biogenic amine content of wines produced using organic methods and of those where traditional procedures were used. Our measurements have proved that it is not possible to clearly distinguish bio-wines from wines produced with traditional methods on the basis of amine content.

  • Reducing nitrate content in lettuce using polyolefin-coated fertilizers
    35-38.
    Views:
    128

    Pot experiments were conducted in order to investigate the effects of the controlled-release characteristic, nitrogen form and application method of polyolefin-coated fertilizers on the nitrate content and yield of lettuce (Lactuca sativa L.). Comparing broadcast application of polyolefin-coated urea (POCU) and urea at four fertilization levels, it was found that application of POCU decreased the nitrate content and increased the yield, due solely to its controlled-release characteristic. Comparing band applications of POCU or polyolefin-coated diammonium-phosphate (POC-DAP) to broadcast application of ammonium nitrate, it was found that a band application of both urea and ammonium containing polyolefin-coated fertilizers can decrease nitrate content in lettuce, without causing any significant yield decrease. This was a combined effect of the controlled-release characteristic and realized ammonium nutrition. Comparing effects of broadcast, band and spot applications of POC-DAP, it was found that nitrate content, was the lowest in the spot application treatment. However, considering both nitrate content and yield, band application was found to be the most effective application method.