كليدواژه :
كود آلي , عناصر غذايي پرمصرف , پلي فنل , كافئين , چاي ارگانيك
چكيده لاتين :
Background and Objectives: There is no scientific report, as an output of field study, related to
short or longterm effects of vermicompost on soil properties and quality of tea green leaves with
the aim of replacement of chemical fertilizers with organic manures and producton of organic
tea, but in trade level this activity has been started in small scale in Guilan province. In order to
study the short time effects of 3 levels of vermicompost on soil properties and quality of tea
green leaf with the aim of possibility of organic tea production, this research has been
counducted in one tea garden with 30 hectares area, located in the side of Foman–Maklavan
road, in Guilan province, in a completely randomized design with 3 treatments and replications.
Materials and Methods: First of all, prune floor has been done in the part of this garden and
plots were separated with 20 square meter area. Then soil samples were taken from surface and
combined and primary experiments have been done, in the end of winter, 2013. Then,
vermicompost, with suitable size (<4 mm), were provided and its important characterictics were
determind and then according to statistical design, it was added to soil surface of each plot in
three levels (0, 0.5 and 2%) and mixed with soil thoroughly by surface plow. During spring and
summer, weed growth has been controlled and sprinkle irrigation has been done. In the end of
summer, soil samples were collected by Auger again and tea green leaf includes a bud plus two
youngest leaves and also third leaf, picked up by mashin and samples were shifted to the tea
research center laboratory. Immediately in plant sample, third leaf was separated from bud pluse
of two youngest leaves, by hand. Then soil and plant samples preparation and soil test and plant
samples analysis include third leaf and bud plus two youngest leaves has been done, separately.
Results: Results indicated an increase in electrical conductivity, cation exchange capacity,
organic carbon, respiration, porosity and moisture content in soil by adding vermicompost in
both levels. The amount of nitrogen, phosphors and potassium in soil samples increased in
treated plots by vermicompost as compared to treatment without vermicompost, significantly,
but there was no difference between treatments of 0.5 and 2 percent. Organic manure
application in both levels (0.5 and 2%) decreased bulk and particle density in soil. In treatment
with 0.5% vermicompost, potassium content and in treatment with 2% vermicompost, K, N and
P content also improved in third leaves. In bud plus two youngest leaves, caffeine content
increased but poliphenoles, total ash and water extract, decreased.
Conclusion: According to the results of this research, it could be concluded that within six
months after application of vermicompost in the soil of tea garden, it improved soil properties
and quality of tea green leaf especially in 2% level and it could provide major part of
macronutrients for tea plant growth. These results, in short time, could be earned, if first class of
vermicompost used, secondly, organic manure mixed with soil thoroughly in application time,
in this sitioation, it is possible to produce organic tea green leaf, witout application of chemical
fertilizers. According to the availability of organic waste in Guilan, scientifically and
practically, production of organic tea green leaf is possible, in north of Iran.
