Year:2006 | Volume:12 | Issue:1 (SUPPLEMENT)|Papers Count:22

Plant genetic resources are important and valuable for crop imporvment. genetic diversity is the base of plant breeding programs. Iran is rich in genetic resources specially for graminae family .unfortunately using of these resources have not been attended. Regarding to intensive use of Agropyron species, some researches planning to use of these diversity for breeding programs For example transferring some characteristics such as resistance to disease, increasing yield and grain quality from wild species to some crops (Triticum,Hordeum and etc). In this research five Iranian species of Agropyron including: Ag.tauri, Ag. desertorum, Ag. elongatum, Ag. trichophorum and Ag. cristatum were studied and karyotype analysis was conducted during mitosis division. for fixation Farmer, for pretreatmrnt colchicines(0.1 gr/lit) and staining was conducted by Feulgen for Mitosis division and Carmin for Meiosis. The results showed that two species are tetrapoloid (2n=28), two octapoloid (2n=56), and one is decapoloid (2n=70). The survey evoulation path, by symertical coefficient for every species was calculated and indicated that elongatum species is more modern.

Seed germination is one of important stages of growth which is a basic requirement for determining optimum plant density in farm. This character is affected by many biotic and abiotic factors including ability of genotypes to tolerate water stress imposed by environmental factors. The objective of this research was to investigate reaction of ten rainfed pea genotypes including seven natives and three improved ones to water stress at seed germination and to determine parameters and an appropriate water potential for screening tolerant genotypes. Experiment conducted as a split plot in a complete block randomized layout with four replications. Main treatments were five water potentials using PEG 6000 and sub-treatments were ten lines including seven natives (MCC13, MCC28, MCC37, MCC44, MCC235, MCC259, MCC258) and three improved ones (FLIP84-480, ILC482. ILC533). Seeds were placed on watman papers in petri dishes in a germinator at 21±1oC. After five and eight days germinated seeds were counted, rate of germination, length of radicle and coleoptyle were measured. Results indicated that with reduction of water potential from zero to-12 bar, seed emergece percentage, at both five and eight days after soaking, and length of coleoptile and radicle root significantly reduced. The reduction in all traits was maximum at changing water potential from zero to-3 bar. The highest differences among genotypes were observed at-6 bar. Among the ten genotypes, ILC533 had a considerable germination at-9 and-12 bar. Length of radicle was the most adverced affected trait from water stress, nevertheless length of radicle was a better parameter in screening genotype for drough tolerance. The best level of water potential for screening genotypes was found to be-6 bar.

To study the effect of plant density on yield and yield components of grain sorghum cultivars an experiment was conducted as factorial based on compeletely randomized block design with tree replications in research field of Birjand Azad university at 2004. In this study four varieties including "Sepideh, Saravan local, Payam and Kimia  and 3 density 100000, 180000 and 260000 plant / ha were investigated. The anova results indicated that varieties were significantly different for grain yield, biological yield, number of seeds per panicle, 1000 kernel weight and harvest index, the highest grain yield, biological yield, number of seeds per panicle and 1000 kernel weight were observed in Saravan local and the highest harvest index was belong to Sepideh. Characteristics such as grain yield, biological yield and number of seeds per panicle were affected by density, and increase of density cause to increase of grian yield, biological yield and decrease of seed number per panicle but were not affected density 1000 kernel weigth and harvest index. Also interaction between variety and density was significant on seed number per panicle. According to the results of this experiment, saravan in 260000 plant / ha density is recommended for maximum grain yield.

To determine the effects of pigweed density on yield and yield components and morphological characteristics of soybean cultivars, a factorial experiment in randomized complete block design form was carried out with three replications. The treatments included soybean cultivars (L11, Clark and Pershing) and pigweed densities (controlled plots, 4, 8, 16 & 32 pigweeds in a meter of row) in soybean plots and plots of pure pigweed. Results showed that between soybean cultivars were different in measured characteristics. Increasing pigweed density decreased grain yield, biological yield, harvest index, number of pods and branches in soybeans. But seed per pod, 100-seed weight, plant height, number of nod in main stem were not affected by pigweed densities. The most reduced grain and biological yields was observed in Pershing and Clark cultivars, respectively. Increasing pigweed density had also declined pigweed plant biomass. Pigweed biomass was affected by competitor soybean cultivars. In Pershing cultivar, this cractristic was less than other cultivars, significantly.

In 1998 ten new varieties of cotton (G.hirsutum & G.barbadense) crossed with two current commercial cultivars of Iran (Varamin and Sahel), these two cultivars used as female and tester parents. In 1999 F1 and parents seeds (20 hybrids and 12 parents) planted in field. The experimental design was randomized complete block with three replications. After analysis of variance for seed cotton yield, earliness, number of bolls and boll weight, traits which had significant F became Line x Tester analysis, then GCA and SCA calculated for each varieties and also we estimated heterosis for each crosses. Results showed that heterosis for seed cotton yield in interspecific crosses more than iteraspicific crosses. Among interspecific crosses, Varamin (G.hirsutum) T-14 (G.barbadense) cross had maximum heterosis (MP=72.3%, HP=71.6%) and in interaspicific crosses was for Varamin (G.hirsutum) B-557 (G.hirsutum) cross (MP=30.68%, HP=13.01%). Varamin cultivar for seed cotton yield and earliness, and Sahel cultivars for number of bolls and boll weight showed maximum and significant GCA than others. Varamin (G.hirsutum) T-14 (G.barbadense) cross showed maximum and significant SCA for seed cotton yield. Evaluation of components of genetic variance explained that were dominance variance more than additive variance for all traits (seed cotton yield, earliness, number of bolls and boll weight.

Present investigation carried out to study different weed control methods in spring safflower under rain fed condition.The experiment was conducted in Sararood Research Station located in west of Iran in 2002. the experiment caried out in Mixed Factorial based on RCBD witht four replications. Factor A was included 4 different herbicides Trifluralin at 960 g a.i./ha, Pendimethalin at 660ga.i./ha, Ethalfluralin at 1172.5 g a.i./ha ,Imazametabenz at 625 g a.i./ha. and Factor B was 4 different method including without mechanical control, hand weeding at the 6 leaves stage, cultivator at 6 leaves stage, hand weeding at the 12 leaves stage + cultivator at 6 leaves stage along with two checks namely without weed, and without anyweed control. The results showed that according to analysis of variance weeds chemical control did not significant effect on seed yield but mechanical control had significant at %1 level on grain yield and dry matter and have not significant interaction of chemical and mechanical control have on yield and related traits of safflower so have not significant difference seed oil percent. Among mechanical methods that used, a hand weeding at 6 leaves stage had highest yield. According to standard method EWRS, effect soil application herbicides on weeds that exite on the area experiment have placed in poor degree and Imazametabenz herbicide in fair degree. With due attention to high plan, number of heads per plant and number of grain per plant safflower had the highest tolerance to Trifluralin and Imazamethabenz herbicides.

For ascertaining the effect of planting pattern on growth indices, An experiment has been performed as Split-factorial design, in the form of complete randomize block with 4-replication on Research Filed of Kalavan in Eghlid in 1382.The main block is with two space row (50 and 60 cm) and secondary block is a composing of two cultivar (Br1, Afshari) and three distance of plant on rows (15,20 and 25 cm).With reducing the space row from 60cm to 50 cm, Root-yield, Content purity and White sugar yield increased significantly and Melas-sugar reduced significantly. Content of sugar and purity on 15 cm distance increased significantly in comparing with 20cm and 25cm. In planting pattern of 15x50 cm the amount of root yield, purity sugar impurity and white-sugar yield differs significantly from 25×60 cm planting pattern. The planting pattern hasnot affected significantly on amount of impurity (a-aminose, Na+, K+).

In order to investigate the effect of six different tempertures on percent of pollen germination and tube length in 17 inbred lines in corn (Zea maize), an experiment was carried out in 2001. To produce the necessary pollens, the lines were planted in three plantin date. pollens were collected between 9-10 a.m. Freshly collected pollen was placed in in 6x1.5 cm petri plates contain modified nutrient medium developed by Pfahler (1976) and Fraleigh (1985), and then immediately exposed to different temperature treatments.percent of pollen germination was investigated in 200 pollen using 5 microscope. tube length was measured in 20 pollen. results showed that some of the lines had greater resistance against heat tension. the best temperture for pollen germination was less than the temperture necessary for tube enlargement. also the difference between pollen germination and tube length in different lines, showed that these characteristics are genetically controled make it possible to produce resistant hybrids. in this study line number 11 showed the greatest percent of pollen germination and the line number 8 showed the longest tube length. according to the results the best temperture for germination was 20 C° while the best temperture for tube growth was 25 Co.

In order to research effect of density and row intercropping different ratios on yield two cultivars wheat, a factorial experiment based on randomized complete block design with three replications was conducted in Ardabil Agriculture Research station in 1999. Factors were: wheat cultivars (dwraf MV-17 almost 65 centimeters and tall Alvand almost 110 centimeters) with three densities (450 seeds m-2 or lower than standard, 500 seeds m-2 or standard and 550 seeds m-2 or higher than standard) and six levels of plating (0; 100, 20:80, 40:60, 60:40, 80:20, 100:0).Mean comparison of intercorpping using LSD method showed that MV-17 and Alvand components were significantly decreased and increased from their pure planting respectively. The number of spikes per square meter had the highest correlation with yield among the evaluated parameters. The competition models of reverse productivity for Alvand and MV-17 in pure planting analyzed using cayera equation and in intercopping were shenozoki and cayera equations. The reverse productivity of single plant in pure planting system of both cultivars had to linear relationship. The productivity of Alvand single plant was equal with 1.21974 of MV-17 and the single plant productivity of MV-17 was equal 0.8732 of Alvand. The intracultivar competition in Alvand was more than inter cultivar competition, while in MV-17 cultivar was vice versa. The differences between inverse productivity of single plant of Alvand in pure cultivation and intercropping was very low. But in MV-17 this difference was relatively high, which showes that Alvand cultivar is more competitive than MV-17.

A two years research was carried out on the impact of water deficiency on the yield of 3 types of oilsunflower in Khoy. The experiment was done in Split Plot of the basis of complete block design in four replications. The irrigation levels were chosen as the main factor in 6 levels (70-70-70, 90-90-90, 110-110-110, 90-70-90, 110-70-110, 110-90-90 mm evaporation from the class A evaporation pan-respectively, From shrub settlement stage to the appearance of head turning into yellow and finally to the physiological survey were put into action). Cultivars of Record, Hisun 33. and Armaverski were chosen as a secondary factor in 3 levels.The comparison of the average Functions indicated that the highest quantity of 100-seed weight the number of the seeds in head , percentage of the core to the entire seed and also the harvest index were attained in the Functions of 70-70-70, 90-90-90 evaporation from the class A evaporation pan. The maximum diameter of the tray with 17.2 cm. and the function of seed and oil, respectively with 5125.4 and 2382.6 Kg per hectare belonged to the function of 70-70-70 mm evaporation. The irrigation care of 90-70-90 mm regarding to the yield of seed and oil , didn’t show a meaningful difference with level 70-70-70 mm. The function of 110-110-110 mm evaporation, the least quantity of seed and oil and its components was attanined , but the percentage of hollowness of the seed in this level was higher than the others. The number of the seeds in the tray showed the utmost corelationship (r=0.711) with the seed yield. Record and Hisun 33 cultivars, concerning the qualities studied, were better than Armaverski cultivar and showed meaningful difference with it. The comparison of the interative averages of the factors showed that the two cultivars Hisun 33 with the irrigation level of 70-70-70 mm had the maximum diameter of the tray, the number of seed in it, and also seed and oil yield. The general results of this research shows that the plantation of oil-sunflower cultivars (Hisun 33 and Record) with the alteration of 90mm evaporation in the beginning and ending of the growth season are suitable for Khoy region. But because of the sensitivity for the water deficiency, the time of irrigation in the appearance of the tray till turning into yellow, must be regulated on the basis of 70 mm evaporation.

Considering the limitations of water resources in the second half of Ordibehesht which coincides the seeding stage of Wheat in W. Azarbaijan, made us carry out a test to distinguish the plant’s need for water at the end of growth season and survey the possibilities of reducing 1-2 irrigation between the cultivars of this product. The research was done in Split Plot of the basis of complete block design where the insufficiency of irrigation as the main factor in four stages: (stem elongation + earing, stem elongation + flowering, stem elongation + earing + flowering and stem elongation + earing + flowering + milk development of the seeds, stage as a witness) and the cultivars of C-73-5 (Sahand), C-73-20 (Shahriar), and the Dorum wheat of Simineh and Zarrin were in focus as the secondary Factors. The experiment was done in Khoy Agricultural Research Station, during the years of 81-82 and the result of the compound analysis of the data indicated that all the qualities surveyed except the quality of tillers in number and seed function were under the deficiency of irrigation and the cultivar. Length of the stem. number of the seed in the spike, length of the spike, Weight of 1000 seeds, biological yield, and harvest index were increased by the alteration of irrigation. The seed yield in the fourth irrigation level was two times more than the first and second level. It was deduced that the reason could be in the ease and creation of the suitable conditions for the transmission of hydrocarbons and the other products of photosyntheses. Since the aim of this research was to eliminate one or two stages of irrigation at the end of wheat growth season, the plantation of the C-73-20 cultivars and their irrigation in three phases: stemming, earing, and setting on flower were considered suitable. By the following of this procedure, level of the land under cultivation will be increased and so will the yield of production on the surface unit.

For evaluation of different irrigation regims on yield and yield component and other traits under drought stress of corn (zea mays L). In order, to study the effect of different irrigation regims on yield and yield components of corn hybrid (S.c704) an experiment was conducted in agricultural research station of Miyandoab during the 2001. Experimental design was split plot based on Randomized Complete Blocks (RCB) in four replications. The main plots were three irrigation regims including 100,160,130 mm. Evaporation from class a pan. The sub plots were different level irrigation consisting of 100, 75, 50 percentage of different level of water requirement. The results showed that grain yield of 100 mm are significantly greater than 130,160 mm. The yield achieved by 100% water requirement was 275 greater than (50%). Lesser kernel per ear and lighter kernels in 160 mm cused reduction in grain yield. Smaller length and diameter ears in 50% water requirement. Caused reduction of kernel number and reduction of kernel size resulted smaller kernels. The effect of three irrigation regims and water requirement on traits was significant. The all traits had a significant correlation between yield and yield components. Path analysis showed that (ASI) had the greatest negative direct effect on yield and 1000 grain weight had the positive direct effect on yield.

To identify drought resistant lines and screening quantitative indices of drought resistance, sixteen lines of barley along with two evidence (Sararood one and Mahalli) were tested in a randomized complete block design with two replications under two irrigated and rainfed conditions in rainfed research station sararood of kermanshah. Based on the potentail (Yp) and stress (Ys) yield, quantitative criteria of drought resistance as: mean productivity (MP), tolerance index (TOL) geometeric mean productivity (GMP), harmonic mean (HM), stress susceptibility index (SSI) and stress tolerance index (STI) were calculated. The results of mean comparision showed that the highest potential and stress yield were related to the line 14. The highest harmonic mean, geometric mean productivity, mean productivity and stress tolerance index were related to the line 14 and the highest stress susceptibility index and tolerance index were related to the line 17. The results of correlation analysis between indices, mean potential and stress yield indicated that the most suitable criteria for screening the lines under two irrigated and rainfed conditions were foure indices geometric mean productivity (GMP), mean productivity (MP), harmonic mean (HM) and stress tolerance index (STI) Based on these three criteria and high yield potential and stress yield, the best drought resistant lines were identified (14 and 11).

Apricot (Prunus armeniaca L.) is a species particularly prone to erratic fruit set. Several causes such as pollen germination and pollen tube growth involve in this behavior. Therefore, Pollen grain was collected from unopened-flowers of Shasti, Nasiri, Hosseini-e-Karimi, Nakhjavan, Shahroodi, Mirzaeai, 35 Shahrood, Shamsi, Noori, Ordobad and Gheisi- Isfahan apricot cultivars. Pollen was stored in dissecator at 3-5oC. Pollens were cultured in a medium including %15 sucrose, 100ppm boric acid and %0.6 agars in sterile petri dishes. The present research was conducted as factorial experiment based on CRD in 3 replications, with two factors: cultivar in 11 levels and counting time after culture in 3 level (10, 24 and 48 hours). Pollen tube growth measured after 48 hour. The results were showed wide range of percentage of germination and pollen tube growth between cultivars. 24 hours was enough for obtain maximum germination. The range of germination was % 18.51-61.23 (mean % 48.28). There were significant differences between pollen tube growth of cultivars. The highest and the least pollen tube length were observed in 35-Shahrood (1278mm ) and Gheisi-Isfahan (717.9mm ), respectively. There was not any significant relationship between germination percentage and pollen tube growth.

In order to evaluate the effects of seed tuber size on growth and yield of potato cultivars moren, an expriment was carried out in 1999 in Miyaneh located in eastern Azarbyjan province. In this experiment was used the randomized complete block design with three replications. In this investigation, was applied the five different sizes of seed tuber (35-45, 45-55, 55-65, 65-75 and 75-85gr). Tuber yield, phonological stages of plant development and many other traits were vary significantly by different size of seed tuber. All of the traits studied were affected by seed tuber size. When seed tuber size was increased, stand percentage; number of tem per unit area, number of days to emergnce and to tuber set and flowering was increased. Result indicated that increasing size of seed tuber increased yield of tuber, but best seed tuber for good yield production economically was seed tuber with 55-65gr.

Experiments were conducted to study the proliferation and rooting ability of Miniature rose. Single-node explants were sterilized and cultured on MS medium supplemented with various concentrations of BA and NAA. Also in different stages, ammonium to nitrate ratios in combination to hormones for number and length of shoot were used different. Combination of 0/5 mg/l BA with 0/05 mg/l NAA was the best treatment for establishment stage. Combination of 0/5 mg/l BA with 0/01- 0/1 mg/l NAA was optimal concentration for multiplication stage. In other establishment experiment optimal ratio of ammonium to nitrate and BA was 37/63 and 1 mg/l for proliferation and shoot length respectively. In the multiplication stage, ammonium to nitrate 0/100 without GA3 for shoot length was the optimal treatment. For rooting higher root formation and the number of roots was obtained using 30 mM Nitrogen than 60 mM. Quick-dip method using 500-mg/l NAA in vitro showed better rooting than other NAA concentrations. Effect of Ammonium to nitrogen on rooting was not significant.

One of the factors which increase cold tension in the plants is ice nucleation activity (INA) of bacteria that produce biological ice nuclei which leads to frosting at higher temperature. In this study four genotypes of almond trees were selected and examined in Zarghan agricultural research center, in Fars province. The four genotypes were 36 (early-flowering), 5 (too early flowering), 26 (mid-late flowering) and 8 (too late-flowering). First, the INA+ bacteria isolated from buds, blossoms, immature fruits & leaves were characterized according to standard bacteriological methods. There after their population densities were determined separately during the months of February, March, April and May, 2002-2003. The strains from Pseudomonas syringae, Pseudomonas fluorescens, Pantoea agglomerans and Xanthomonas spp. were identified as INA+ bacteria. To P.syringae was the most prevalent bacterium and P.agglomerans, P.fluorescens and Xanthomonas spp. were ranked second to the fourth, respectively. Bacterial population changed completely depending on the phenology of the plants and the temperature. Moderate temperatures of February and March, induced early flowering almond genotypes to blossom in Zarghan area of Fars province. Since population of epiphytic INA+ bacteria on almond trees will be increased by moderate temperature and adequate nutrition, any decrease in temperature will intensify on frost injury of almond trees. It was concluded selected almond genotypes, weather condition and population of INA bacteria are the most effective factors in frost damage of Zarghan area.

In a survery conducted in 2000, 184 bacterical is olates were collected from rhizosphere of different rice fields. To assess, Their antagonistic activities against Rhizoctonia solani To assess their antagonistic activities,all strains were screened against R. solani usingPark test in dual cultures. Results showed that 47 isolates mostly belong to Gram-posivtive bacteria and some fluorescent pseudomonads, the antagonistic bactera were identified as The strains encoded 5, 93, Ifu, B29 and T42 were identified as Pseudomonas fluorescens, strain 24 as Bacillus cereus, strains 29 and 120 as B. subtilits,on the basis of biochemical, physiological and morphologicaland characters. Of these, strains with strong and promising antagonistic activity were select for further studies. In total Strains 5, 93, T42, 24, 29, 120 inhibited normal mycelia growth of the fungus, whereas the strains 5 and T42 showed super antagonistic activities. In greenhouse trial, both bacterial strains as well as Tilt treatments did reduced variably sheath blight of rice plants. All strains infirst and second experiments could promote the plant height, whereas strains both of 5, T42 could increase the numbers of tillages. Increasing the root length by strain T42 and plant dry weights by strains 5, 93, T42, 24 were some othere promising results, otained in these experiments.

This research was carried out during 2000 in the research farm of Agricultural and Natural Resources Research Center of Qazvin. The aim was application of naturally born materials with the least effects on biological factors .Jhm was applied with four doses /05, /10, /15 and /20 percent on late fourth instar and early fifth instar nymphs. The design was based on randomized complete block in field and lab. Results showed that 100 percent of nymphs in lab treated nymphs showed morphologic changes when transformed to adults. According to analysis morphological changes in field showed significant difference with controlat %95 level. Five wheat spikes were dissected randomly from each replication and the percent seed damage was calculated. In all replications, the highest seed damages were recorded for control. The damages were decreasing when JHM doses were increased, and the least damage was recorded with 0/02% dose.

In this study antaginistic effects of some bacteria isolated from mulberry tress were assessed against Fusarium solani, Fusarium oxysporum and Lasiodiplodia theobromae under laboratory condition. Five bacterial isolates were able to suppress the fungal growth at the rate of 1-5 mm on PDA. Four of the bacterial strains (H1, H16, H24, H25) were identified as Bacillus spp. and the strain H4 was assigned as Pseudomonas fluorescence. The volatile metabolites released from antagonistic bacteria could inhibit the growth of fungi Fusarium solani, Fusarium oxysporum, Lasiodiplodia theobromae at the rate of 25 to 35, 36.11 to 47.35, 25.18 to 76.66 percent, respectively. H4 strain produced sidrophore on King B medium which contained 5, 50, 100 mmol Fecl3 which inhibited the mycelial growth of the Geotrichum candidum. The extracellular extracts of selected antagonists reduced the vegetative growth of pathogenic fungi by increasing the extracts concentration. In addition antagonistic bacteria could produce antibiotic substances which led to stop the fungal growth.