نشریه فنآوری تولیدات گیاهی
سال سیزدهم شماره 1 (تابستان 1392)

This research was conducted as two separated experiments based on a randomized complete block design with three replications at research farm of Agricultural Faculty of Bu-Ali Sina University، Hamedan. In both experiments، Alvand and Sayson cultivars were one of the experimental factors which were planted at 450 plants m-2. In the 1st experiment، feral rye (Secale cereale) plant densities of 0، 20، 40، 60 and 80 plants m-2 and in the 2nd experiment، wild mustard (Sinapis arvensis) plant densities of 0، 8، 16، 24 and 32 plants m-2 were the 2nd experimental factor، respectively. By increasing feral rye and wild mustard plant densities leaf area index، dry matter accumulation and weed growth rate، leaf area index duration and dry matter duration of weeds were increased. In each level of weed plant density، all above mentioned traits of weed in interference with Sayson were more than Alvand. Feral rye height in competition with both cultivars was not changed. But، wild mustard height in interference with Alvand was more than competition with Sayson. However in non-interference conditions، Sayson in traits of leaf area index duration، dry matter duration and grain yield has significant superiority than Alvan. But in interference condition with both weeds، these traits in Sayson were more affected than Alvand. Canopy height of Sayson was reduced in interference with both weeds. But canopy height of Alvand was increased in interference condition. Maximum leaf area index and growth rate، dry matter، leaf area index duration and dry matter duration of wheat cultivars were indicated positive and significant correlation with grain yield of both cultivars. In contrast، amount of above mentioned traits in each of two weed species had robust negative correlation with grain yield of two wheat cultivars. Generally، in interference with each two weed species، Alvand indicated better reaction than Sayson، and for sowing in spotty field to studied weeds is suggested.

Tomato is a climacteric fruit and its ripening can be completed after harvest. Provided that appropriate storage condition for a given harvesting stage is implemented، fruits are endowed with proper quality for the market. In order to study the effects of maturity stage on fruit storage life، tomato fruits were harvested at three ripening stages. They were stored at three storage conditions i. e. 5 ˚C، 13 ˚C، and a simulated condition (SC) of the interval between harvest and consumption by the consumer. Fruit color، lycopene، firmness، pH، titratable acidity (TA)، total soluble solids (TSS)، ascorbic acid، weight loss، and chilling injury (CI) were measured and evaluated during the experiment. Results showed that at the end of the storage at 13 ˚C، mature green fruits had relatively similar values of color، lycopene content، TA، TSS، and firmness compared to the red ones، with the exception of their ascorbic acid. While storage of different maturity stages of tomatoes at 13 ˚C developed normal ripening، storage at 5 ˚C and SC disturbed the normal ripening process.

Effects of nitrogen (100 and 200 kg/ha) and irrigation levels (water stress at 8-10 leaf stage، water stress at milk till dough ripening and full irrigaiton) on grain filling and yield of two corn (Zea mays L.) cultivars (SC 500 and SC 647) evaluated through conducting field experiment in research farm of Bu-Ali-Sina University. The experiment was established as a completely randomized block design in a factorial split arrangment with three replications in 2008 growing season. Fertilizer and irrigation levels allocated to main plots and corn cultivars conducted to the subplots. Plant growth rate at flowering per kernel (PGRflw-kernel)، grain filling rate (GFR)، effective grain filling duration (EGFP)، plant growth rate at milk till physiological maturity (PGRM-M)، kernel number، kernel weight، SPAD at grain dough ripening، correlation between these characteristics and indexes were measured. application of 100 kg/ha nitrogen and water deficit stress at grain milk till dough ripening stages lead to decrease in PGRM-M، reduction in grain filling rate and grain weight. Water deficit stress at 8-10 leaf stage، reduced duration of effective grain filling. Highest yield obtained from applying 200 kg/ha nitrogen and full irrigation. Least effect of water stress on yield obtained from application of 200 kg/ha nitrogen and water deficit stress at grain milk till dough ripening stage.

Ascorbic acid is one of the most important water-soluble antioxidant in plants، which involves in biotic and abiotic stresses as a nantioxidant molecule. This study was designed to investigate the effect of foliar spraying of ascorbic acid on physiological، biochemical and growth characterstics of strawberry cv “Selva”. A factorial experiment was conducted in completely randomized design with three levels of NaCl (0، 15 and 30 mM) and three levels of ascorbic acid (0، 1. 5 and 3 mM) with three replications in greenhouse. The results showed that the dry and fresh weight of leaves and roots decreased in stressed plants while ascorbic acid spray significantly increased these parameters. Salinity stress also significantly decreased some physiological characteristics such as leaf relative water content، chlorophyll a، b and total chlorophyll، but increased ion leakage. The foliar application of ascorbic acid significantly increased relative water content، chlorophyll a، b، total chlorophyll and decreased ion leakage. The rise in sodium chloride concentration، elevated proline and soluble carbohydrates in leaves. Spraying plants under salinity conditions with ascorbic acid increased soluble carbohydrates while had no significant effect on leaf proline content. Leaf soluble proteins showed a significant decrease under salinity treatments and with application of ascorbic acid increased. According to the results of this study، foliar application of ascorbic acid can be recommended in order to reduce the harmful effects of sodium chloride on strawberry plants.

Tulip (Tulipa spp. L.) is one of the most important flower bulbs worldwide with high distribution in many parts of Iran. This genus belongs to the family Liliaceae and consists of about 100 species of them 19 species are native to Iran. In this study، morphological diversity of 49 populations within 9 species of tulip، which had been collected from 12 provinces، were evaluated. The results of quantitative morphological traits (total stem length، plant height، stem diameter، leaf length، leaf area، leaf number، petal length، petal area، stamen length، pistil length، bulb length، bulb diameter) showed، effect of species and populations were significant in all traits، and also characteristics of petal area and petal length، showed the highest and lowest coefficient of variation، 47. 09 and 6. 77 respectively. The cluster analysis in the four distance divided populations into seven groups. A high correlation coefficient was observed in most of the traits. The results of the correlation coefficient indicated، the highest correlation (97%) between total stem length and plant height which was significant at 1% level. Evaluation of flower color as a qualitative trait observed، high color variation between species and showed high variation in color intensity within populations. The results can be used for germplasm management and also to determine the relationship between species.

In order to study the effects of rhizobium and plant growth promoting rhizobacteria on yield and yield components of bean (Phaseolus vulgaris L. var. Sadri)، an experiment was carried out at Research Station of Ekbatan، Hamedan province during 2010-2011 cropping season. The experiment was conducted in factorial on the basis of randomized complete block design (RCBD) with three replications. Factor A، including 4 levels of Rhizobium legominosarum bv. Phaseoli (Rb 147، Rb 114، Rb 116 and no inoculation) and factor B، consisted of four levels of promoting growth plant rhizobacteria (Azospirillum lipoferum 21، Azotobacter chroococcum 5، Pseudomonas putida 168 and no inoculation). The result of analysis of variance showed that different races of rhizobium and promoting growth plant rhizobacteria (PGPR) had significant effects (p< 0. 01) on number of pods per plant، harvest index and seed yield. But there were not significant effects on number of seeds per pod، 100 seeds weight and plant height. The highest number of pods per plant was obtained by inoculation of RB116 along with Azotobacter which produced 43 percent higher than no inoculation. Inoculation by RB116 without promoting growth plant rhizobacteria could produce the highest harvest index which was 57 percent higher than check. The highest seed yield (3812 kg/ha) was achieved by inoculation of RB116 along with Azotobacter which produced 80 percent higher than no inoculation.

In order to study the effect of water deficit stress on growth، yield، essential oil content and composition of geranium (Pelargonium graveolens L.)، a greenhouse experiment was carried out based on a completely randomized design with four treatments and four replications. The water deficit stress treatments were 100%، 85%، 70% and 55% of field capacity. Results showed that as the soil water content decreased، plant height، stem diameter، number of auxiliary shoots، fresh and dry herb yield and essential oil yield decreased. Although the highest essential oil content (2. 04% based on dry weight) was found in plants treated with 55% of filed capacity، due to dramatic decrease in growth، their oil yield (0. 065 g plant-1) was the lowest compared with those of plants treated with 100%، 85%، 70% of field capacity. The highest oil yield with 0. 193 g plant-1were found in plants treated with 100% of field capacity. The amount of some of the main components of oil i. e. Citronellol، Citronellyl formate and iso-Menthone were not affected by water deficit stress treatments. However، as the soil water content decreased، the amount of α-Pinene and Linalool decreased، while the amount of 2-Phenylethyl tiglate and Germacrene-D increased. Moreover، the highest amount of Rose oxide (cis and trans)، Spathulenol، cis-Citronellyl tiglate and the lowest amount of Neral، Geraniol and Geranyl formate were found in plants treated with 55% of field capacity، while those of plants treated with 100%، 85%، 70% of field capacity were not significantly different. Due to the effect of water stress on herb yield، the yield (mg plant-1) of the main components decreased as the soil water content decreased.

Heavy metals are one of the most important environmental pollutants among dangerous pollutants. Turfgrasses are as lowest surface of landscape and close to these pollutant particles. Thus، they could absorb these mentioned pollutants. In this work، the effects of heavy metals including essential ones such as copper and zinc and non-essential such as silver (in two forms of silver nitrate and nanoparticles) on seed germination stage and callus regeneration in In Vitro of Bermudagrass were investigated. The metals concentrations which used were 0، 5، 10، 15 and 20 mg/L. The results showed that zinc and copper have important role on seed germination and somatic embryogenesis of Bermudagrass. Application of silver nitrate stimulated the adventitious rooting induction of calli and radicle growth in seed germination. Further، the toxicity effects of silver nanoparticles were evident in all stages of growth and development in In Vivo and In Vitro of Bermudagrss.

Microplants derived from tissue culture of two potato cultivars (Agria and Sante) were inoculated with two species of mycorrhizal fungi. Inoculation was being done when microplants transferred in to the greenhouse. A pot experiment was conducted using a factorial based on randomized complete blocks design with four replications. The factors were mycorrizal inoculation (non-inoculated and inoculated with Glomus mosseae، Glomus etunicatum and mixture of them) and two cultivars of potato. Eight weeks after inoculation، colonization percentage was assayed. In addition، plant growth regulators including Auxin، Cytokinin and Gibberellin were measured. After harvesting، minitubers were separated and total yield was estimated. In addition، dry matter of minituber was determined. Results showed that inoculants of mycorrhizae had significant effect (p≤0. 05) on colonization، minituber production and level of all plant growth regulators. Interaction effect of cultivar and inoculants in minituber size and weight was significant by probability of α= 0. 01 but was significant by probability of α= 0. 05 in Gibberellins levels and colonization percentage. By mean comparisons، it was demonstrated that inoculation with G. etanicatum and mixed inoculants had more positively effect on colonization severity، minituber production، and level of all plant growth regulators comparison with G. mosseae. The highest amount of minituber (13. 81 No and 40. 59 gr in mean weight per plantlet) was achieved in mixed inoculants that significantly (p≤0. 05) was different with two separated inoculants and control treatment. Dry matter of minituber was increased significantly (p≤0. 05) by application of mixed inoculant and separately mycorrhizal inoculants comparison with control treatment in two cultivars.