مجله علوم و فنون باغبانی ایران
سال شانزدهم شماره 3 (پاییز 1394)

The important problem of quince and pear orchards¡ in country¡ is sensitive of this trees on chlorosis that occurrence because of present of bicarbonate in soil or irrigation water. So tolerance to Fe deficiency of seedling rootstocks of quince¡ Q.B¡ Q.C and PQBA29 were evaluated by exposure to two levels of Fe (3 and 50 µM) in the presence or absence of bicarbonate (10 mM) in soilless culture in greenhouse condition. Results showed that in PQBA29 vegetative growing factors¡ relative leaf chlorophyll¡ chlorophyll fluorescence¡ leaf active Fe¡ leaf electrolyte leakage¡ relative water content of leaf and catalase activity was less influenced by low concentration of Fe or present of bicarbonate in nutrition solution¡ in comparison with other rootstocks. In this condition¡ seedling rootstocks of quince was more susceptible to iron chlorosis. Also Q.C showed better performance in comparison with Q.B¡ in iron deficiency condition.

Plant growth and photosynthetic rate are affected by water deficit and high temperature as environmental factors in many areas. Whereas most of the time¡ both of these stresses happen synchronous¡ few information has already been reported about their interaction effects on plants and also the role of mychorizal arboscular in these conditions. In this research the effects of mychorizal arboscular (Glomus etunicatum) on growth and physiological traits was considered in two grape cultivars („Perllet‟ and „Yaghouti‟) under two irrigation levels (water deficit for 9 days and field capacity regimes) and three temperature levels (25¡ 40¡and 40°C). This experiment was conducted on the basis of randomized complete block design with 4 replications in a greenhouse. Results indicated that fresh and dry weight were decreased in two cultivars („Perllet‟ and „Yaghouti‟) under drought stress¡ high temperature stress was not effective on photosystem II efficiency alone¡ but drought stress decreased photosystem II efficiency. However photosystem II photochemical efficiency was decreased more when drought and high temperature stresses were combined. The fungus improved tolerate of the perllet cultivar which were under drought stress and 40 °C temperature. Therefore¡ the fungus prevent decrease of the chlorophyll index in this cultivar. Both Perllet‟ and „Yaghouti‟ cultivars were recovered during 4 days. Generally these cultivars were resistant to high temperature stress but their growth rate decreased under combind drought and high temperature stresses.

This research aimed to achieve the most effective levels and the methods of iron fertilizer application to improve the quantitative and qualitative characteristics of date palm cv. „Kabkab‟. The experiment was performed as a randomized complete blocks design consisted of fourteen treatments and three replications on fourty two palm trees. The treatments included: control¡ soil application of iron sulfate at four levels (500¡ 1000¡ 1500 and 2000 g per tree)¡ application of iron chelat at three levels (50¡ 100 and 150 g per tree) and trunk injection of iron sulfate in six levels (0¡ 10¡ 15¡ 25¡ 35 and 45 g per tree). The results showed soil applications of 1500 g iron sulfate¡ 100 g iron chelat and 15 g injection of iron sulfate lead to increasing quantitative and qualitative traits of fruit such as percentage of total soluble solids of fruit¡ the percentage of fruit flesh and¡ nitrogen¡ phosphorus and potassium content of fruit. However¡ soil application of iron fertilizers in calcareous soils of south provinces in addition to high costs (chelated iron)¡ creates insoluble oxides and hydroxides of iron (ferrous sulfate). Thus by injection of 15 g iron sulfate treatment (in comparison with the two treatments mentioned above)¡ various parts of the plant directly received iron and overcome the problem of absorption and transport of iron in calcareous soils.

Lisbon‟ lemon is a tropical fruit which sensitivity to chilling and decay cause limitation for it‟s maintenance at low temperature storage. This research was aimed to apply salicylic acid for resistance to chilling and subsequent decay reduction and maintaining quality of the „Lisbon‟ lemon fruit during low temperature storage. The experiment was performed as a completely randomized design consisted of four treatments and three replications. Treatments included: application of salicylic acid at 0¡ 200¡ 400 and 600 mg l-1. The fruit immersed for five minutes in different concentrations of salicylic acid. After treatment¡ fruit were placed in plastic bags and stored at low temperature (5±1℃) and a relative humidity of 85±5% for two months. The results indicated that application of salicylic acid¡ especially at 400 and 600 mg/l could maintain the internal and external quality of the fruit and exert satisfactory effects on chilling resistance compared with the control. Overall¡ application of 400 mg/l salicylic acid caused the least amount of weight loss and electrical conductivity (ion leakage)¡ also chilling injury and decay¡ the protection of vitamin C¡ total soluble solids¡ acidity and pH in optimum range in „Lisbon‟ lemon fruit during low temperature storage.

This study was conducted to evaluate the effects of several kinds of bed substrates on growth characteristic of Monstera deliciosa. The cultivation of this plant was done in order to increase the use of agricultural wastes which are found around Caspian sea region and replacing them into peat (as a standard bed substrate). This experiment was performed in a randomized complete block design with 10 treatments and 3 replications. The bed substrates included leaf mould (Oak¡ Breech)¡ tea wastes¡ rice hull and peat moss with different ratios. The results indicated that the substrate treatment had significant effect on growth indexes. Results showed that the number¡ length and width of leaves and roots dry weight were high in plants treated with 50 % leaf mould 25% rice hull 25% peat. Plants treated with 50% tea waste 25% rice hull 25% peat had the maximum leaf length and wet and dry weights of root. Also¡ the number and length of leaves were appropriate. According to results¡ chemical and physical characteristics of bed substrates¡ the mentioned treatments are suggested as bed substrates which this plant have the most growth among other examined.

In this experiment¡ the effects of drought stress and different levels of shade was studied on growth characteristics of transplant dwarf cultivar „Matador‟ of Lisianthus in a factorial design with two factors of irrigation and shade. After germination and in the 2-3 leaf stage of plantlet¡ treatments were carried out such as irrigation (100%¡ 75%¡ 50% of FC) and shade (0%¡ 50%¡ 70% of natural light intensity). 100%¡ 75%¡ 50% of FC irrigation equivalent 1 day after¡ 2 days after and 3 days after irrigation and 0%¡ 50%¡ 70% shades equivalent full sunlight (an average of measured radiation of 1852 µmol m-2 s-1)¡ 50% (an average of transmitted radiation of 926 µmol m-2 s-1)¡ 30% (an average of transmitted radiation of 557 µmol m-2 s-1 ) of light intensity¡ have been carried out¡ respectively. 100% of FC irrigation (1 day after irrigation) and 0% shade (natural light intensity) were considered control. According to the results the number of flowers and flowering branches decreased significantly¡ by increasing the irrigation levels; while the number of days from planting to flowering was increased. With increasing shade level compared to 0% (no shade) flower number¡ flower diameter and number of flower branch were increased. Maximum wet and dry shoot weight¡ relative chlorophyll content¡ soluble carbohydrate and photosynthetic performance were obtained with 100% of FC and 50% of shade. This treatment is recommended to produce seedlings dwarf cultivar „Matador‟ of lisianthus in nursery for urban landscaping of the current experiment conditions.

This study was conducted to find a new and inexpensive way to improve postharvest life of strawberry fruitwhich were designed as factorial experiment in completely randomized design with 4 replications. The factors included: cultivars („Camarosa‟ and „Parus‟); salicylic acid (0 (control)¡ 0.5¡ 1 and 1.5 mM) and measuring time (0 and 11 days after storage). Foliar spraying was carried out in two stages (white and pink) and the fruits were harvested at commercial maturity and stored at 2±1
ºC and 90±5% (RH). The results showed that 0.5 mM of salicylic acid was identified as the best treatments for maintaining the strawberry firmness (0.39 kg) and delaying the weight loss and microbial activity at the end of storage. Total phenolic content and antioxidant activity of treated fruits by salicylic acid 0.5 mM was increased by 18.53 and 22.33%¡ respectively. Salicylic acid 0.5 mM showed the highest a*¡ L*¡ Chroma skin and anthocyanin content. In general¡ it could be concluded that preharvest salicylic acid application improved the quality and antioxidant activity of strawberry fruit (Fragaria ananassa cvs. „Camarosa‟ and „Parus‟)¡ and is very effective in increment of shelf life and nutritional value of fruit.

Bell pepper is on of the warm season crops. However¡ at temperatures above 30 ˚C in summer flower abscission are formed and reduce fruits yield. This experiment was carried out to investigate the effects of spermidine (0.1¡ 0.5 and 1 mgl-1 )¡ methyl jasmonate (0.001¡ 0.01 and 0.1 mM) and distilled water (control) to reduce the effect of high temperature on flower abscission of bell pepper plants. The experiment was done in a randomized complete block design in three replications. The plants were foliar sprayed at 5-6 leaf stage (before flowering) for two times with five day interval. Results showed that treatment with spermidine increased plant hight¡ number of lateral branches¡ relative chlorophyll¡ number of flowers¡ fruit set¡ fruit yield¡ ¡ antioxidant capacity¡ fruit vitamin C and reduced flower abscission significantly compared with control. Application of methyl jasmonate also led to significant increase of relative chlorophyll¡ fruit set¡ fruit yield¡ vitamin C and antioxidant capacity but reduced flower abscission and showed no significant effect on lateral branches¡ plant hight¡ the number of flowers compared with control. Application of spermidine on flower formation¡ increasing fruit yield and reducing flower abscission was more than methyl jasmonate. Finally¡ these plant growth regulators were able to reduce flower abscission increase flower formation¡ fruit set and yield.

To investigate the effects of mycorrhizal symbiosis on growth and some physiological and eco-physiological properties of almond rootstocks in drought stress¡ a factorial experiment in a completely randomized design with three factors including four mycorrhiza (without mycorrhiza¡ Glomus mosseae¡ G. intraradices and a mixture of two species)¡ three levels of drought (Daily¡ 3 and 6 days irrigation intervals)¡ two almond rootstocks (Shurab 2 and GF677) were performed in 3 replicate.The results showed that interactions of mycorrhizal fungi species¡ drought levels and almond rootstock had significant effect on growth parameters like root and shoot dry weight¡ length of root system¡ shoot height¡ leaf area¡ number of leaves and mycorrhizal colonization percentage. Application of mycorrhizae increased plants growth compared to control plants. In response to drought stress¡ osmotic regulation processes were actived in almond rootstocks. Proline and soluble sugars of plant leafincreased¡ but this process in leaves of mycorrhizal plants was less than mycorrhizal plants. In general¡ the results of this study showed that the Shurab 2 rootstock is more resistant to drought stress than the GF677. Plant mycorrhizal were less affected by the drought stress.

In plant breeding programs¡ polyploidy inductions have been used for producing new cultivars with improved vegetative organs in many plants. Polyploid plants typically associated with changes in anatomical¡ morphological¡ physiological and biochemical traits. In this experiment¡ 0.02¡ 0.04 and 0.06 % colchicines concentrations were applied to the cotyledon and two true leaves stages for investigating the effect of autotetraploidy induction on some stem and leaf anatomical traits of pot marigold. Cytometric studies showed that at two true leaves stage¡ sprayed plants with 0.06% colchicin concentration were significantly induced the highest levels of polyploidy (60.06% and 58% in the genotype of yellow and orange flowers respectively). While¡ the highest mortality rate was obtained in treated plants with 0.06% colchicines concentration at cotyledon stage. Results of leaf anatomic traits in diploid plants with tetrapolid plants showed that length¡ width and number of chloroplasts of stomata guard cells were increased in tetraploid plants compared with diploid plants¡ but stomata density per area was declined. Also¡ the vascular bundles length¡ the phloem and xylem thickness and stem diameter to pith length ratio were significantly increased (P