Amir Lakzian; Vali Feiziasl; Ali Tehranifar; Akram Halajnia; Hadise Rahmani; Payam Pakdel; Seyyed Hedayat Mohseni; Arezo Talebi
Abstract
Dieback of trees is a serious problem in many different regions of the world and city authorities are concern about conserving and maintaining the green spaces in the big cites. This study was conducted to evaluate the early dieback and yellowing of sycamore trees (platanus sp.) by using a completely ...
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Dieback of trees is a serious problem in many different regions of the world and city authorities are concern about conserving and maintaining the green spaces in the big cites. This study was conducted to evaluate the early dieback and yellowing of sycamore trees (platanus sp.) by using a completely randomized block design (Split Split plot) in 15 replications (sites) in 2009. The main plot was plant sampling times (spring, summer and autumn), sub plot was the plant condition (green and yellow) and sub-sub plot was the place of sampling on the tree (down, middle and upper). After sampling, preparation and chemical analysis, total nitrogen, phosphorus, potassium, iron, manganese, zinc and sodium were measured by standard methods and the data was interpreted by using site regression model (GGE biplot analysis). The results showed that nitrogen deficiency was occurred with more intensity in the down layer in summer time compare to the spring time. The results also showed that iron deficiency occurred in the yellow tree groups and zinc deficiency also occurred simultaneously. However zinc deficiency was not proven in the spring time but it occurred in summer time. Iron deficiency was started in the spring time and then more deficiency observed in summer time. With regarding to the obtained results it dose not seem that nutritional deficiency is the main reason of dieback of sycamore trees in Mashhad. These symptoms also might be caused by drought stress and water deficiency, low temperature in winter or early spring. Fungi attack and other diseases can cause similar symptoms.
Payam Pakdel; Ali Tehranifar; Seyyed Hossein Nemati; Amir Lakzian; Seyyedeh Mahdiyeh Kharrazi
Abstract
Abstract
To study the effects of four types of mulches including wood chips, municipal compost, sawdust and gravel in three different thicknesses on growth of Platanus orientalis during two years, an experiment was conducted in Mashhad area with semi-arid climate. The research was conducted as split ...
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Abstract
To study the effects of four types of mulches including wood chips, municipal compost, sawdust and gravel in three different thicknesses on growth of Platanus orientalis during two years, an experiment was conducted in Mashhad area with semi-arid climate. The research was conducted as split plot based on a completely randomized block design with four replications. Treatments included control (no mulching) and four types of mulch including wood chips, municipal compost, sawdust and gravel in three thickness (5, 10 and 15 cm). During the study, soil moisture and temperature, total leaf number, fresh and dry weight of leaves, tree height, fresh weight of tree, trunk circumference at height of 20 cm from soil surface was measured. Sawdust mulch with 15cm thickness had highest soil moisture and lowest soil temperature. All factors in sawdust mulch with 15cm thickness showed the highest growth characteristics. In all factors (tree fresh weight, leave fresh and dry weight, tree height, total number of leaves and trunk circle at 20 cm height) increasing of mulch thickness led to increased rate of growth and the best results was observed at 15cm thickness of all kinds of mulches. There were no significant difference among mulch types on height of the tree but all mulch types had significant difference with control. In the other measured factors including total leaf number, fresh and dry weight of leaves, fresh weight of tree, trunk circumference at height of 20 cm from soil surface, the highest growth was related to sawdust, wood chips, compost, gravel and control, respectively. It seems that sawdust with keeping soil moisture and reducing drought stress could help better growth of the plants compare to other mulches in dry and semi-arid areas.
Keywords: Mulch, Plane, Soil moisture, Soil temperature, Growth factors
