استفاده از شاخص هاي فيزيولوژيك رشد در بهره برداري مناسب از گل زراعي

Application of physiological growth indices lor suitable harvesting of Hypericum perforatum

Growth indices are useful for interpreting plant reaction to the environmental factors. Using Growing Degree Days (GDD) for estimating the phenological growth stages is more valid instead of calendar lime. Due to determining utilities of the physiological growth indices in suitable harvesting of Hypericum perforatum, a split plot design in complete randomized block design (CRBD) was used. The main plots were 3 densities and sub plots were 4 different fertilizers. Dry Matter, Leaf Area Index, Relative Growth Rate and Crop Growth Rate were measured in 8 sampling stages during the growth period of Hypericum perforatum. Polynomial equations were known as the best indicator for interpreting of growth indices fluctuation according to the ODD. The highest dry matter was accumulated in 2400-2800 GDD. Maximum leaf area index of Hypericum perforatum reaches to 2.8 in 10 plants mJ. Tops harvest regulation according to max leaf area index which occurred in 1800-2000 GDD, led to increasing the hypericin as secondary metabolite. Pure chemical fertilizer application and stimulating the vegetative growth, causes increasing the RGR and CGR in the (lowering stage and producing more dry matter. While application manure and mixed fertilizer decreases these growth indices in the flowering and increase the hypericin and quality.