Seed and Plant
Year:2000 | Volume:16 | Issue:1|Papers Count:13

Study of morphological and agronomic characters affecting forage yield of four local (Hamadani, Bami, Yazdi and Ghara Yonjeh) and three improved (Euwer, Pearce and Pioneer 581) alfalfa cultivars, was carried out in field at spn Experimental Station in Karaj in 1996-97 growing seasan. The design of the experiment was split plot in time which replicated 4 times. In general, at lower productivity potential, local cultivars showed priority to non local cvs. However, as procblctivity potential improved, improved cultivars showed better adptation and produced higher forage yield. The results of the experiment revealed that cultivars were statistically different in fresh yield, dry matter yield, yield per shoot, different plant organ dry matter, regrowth rate, first flowering node, plant hieght, number of nodes in main stem, length of internodes in the main stem, number of stems per area, length and width of leaflet, main and lateral branches of main stem. Forage yield was higher in first harvest and percentage of dry matter produced in first, seconde and third harvests were 36.30, 33.68 and 27.45 respectively. Among the cultivars, Pioneer 581 and Hamadani showed superiority, concerning many morphological and agronomic characteristics, which resulted in production of higher yields and could be recommended as suitable cultivars for karaj area.

The present study was carried out to identify Fusarium species causing head blight on barley in Mazandaran province during 1994-95. From 260 Fusarium samples, isolated from infected barley spikes, Fusw1um graminemum, F. culmorum F. avenaceum, F. graminum, F. lateritium, F. semitectum and F. reticulatum were determined. F. avenaceum, F. lateltium and F. reticulatum were species which are reported for the first time from barley spikes in Iran. F. gramineamm, with 112 isolates, was the most frequent species on barley spikes in Mazandaran. All of the isolated species could cause head blight on barley spikes in the greenhouse. The pathogenicity of F. graminum, F. reticulatum, F. semitectum, and F. lateritiUln on barley spikes was also the first report in Iran.

This study was designed in Karaj to investigate optimal allocation of outputs determine their effects on yield, to calculate the value marginal and average product, to determine elasticity of production of inputs and economic assessment of wheat farmers. After selection of villages, the requierd date werre obtained from 102 farmers from 11 villages who were selected by simple random sampling method. In this study, farmers were separated into two groups: 1) Those who used modern cultivars (Mahdavi and Almout), and 2) those who used old varieties (Ghods and Falat). The results indicated that: 1) for group (a), gross income and yield (per ha) were 16.7 percent higher than those of group (b), 2) for group (a), the production cost was 14.3 percent lower than group (b), 3) the farmers income had inceased considerably by using moder cultivars, 4) the effect of cultivar in yield was 20 percent, and 5) area planted, water, labour, phosphate fertlizer and chemicals were used on optimum but seed and urea were used higher than optimum level hy farmers.

An experiment was conducted to determine the responses of four hexaploied wheat cultivars (Ghods, Rassul, Kaveh and Moghan 1) and one derived doubled haploid line (DH19) from Ghods cultivar, to anther culture. The CHB liquid induction medium with two concentrations (90 g/1 and 145 g/1) of two carbohydrate sources (maltose and sucrose) were used. The experimental design was factorial on basis of randomized complete-block design with three replications. The plants were grown in a greenhouse with a photoperiod 16h /8h (day / night) at temperature 25oC /15oC (day / night). Each replication consisted of one pot with three plants. The number of embroys and total plants regeneration as well as the number of green and albino plants regenerated per 100 anthers, were measured. Overall, 15000 anthers were studied and results showed that genotype, induction medium composition and their interactions significantly affected the embryo formation, total, green and albino plants regeneration. Among the culture media and cultivars, 90 g/1 maltose and Moghan 1, respectively, had the highest frequency and the best performance for embryo production, total, green and albino plants regeneration. Also, Moghan 1 cultivar on induction medium of 90 g/1 of maltose, had the best responses for embryo production, and the total, green and albino plant regeneration of 72.47,36.73,22.70 and 14.03%, respectively.

In order to determine the effects of row spaces and planting dates on the yield of three hybrids of silage corn in Shahrekord region, an experiment was carried out for two years (1996-1997) in split - polt design with three replications in Chartakhteh Research Station in Shahrekord. Two row spaces (60 and 75cm) were considered as main plots, and three planting dates (21 May, 9 June and 29 June), and three hybrids, (SC704, SC301 and SCI08) in factorial form as subplots. The collected date were analysed statistically based on variance analysis on yield for each year and combined variance analysis for two years. Effect of year was significant at 1% level, and average yield in 1997 was 11 ton/ha more than that in 1996. Effect of row spaces was significant at 1% level, and average yield in 60cm row space was 7 ton/ha more than that of 75cm. Effect of planting date was significant at 1% level and highest yield was obtained in the first planting date (21 May). Effect of hybrids was also significant at 1% level and the highest yield was obtained from SC704. In the third planting date (29 June) hybrid SCI08, due to early maturity, was more suitable than other hybrids.

There is strong sink for carbohydrates during fruit growth period especially in the "on year" season of pistachio trees. This situation leads to a competition for metabolies between vegetative and fruit growth causing a reduction in nut quality. This experiment was conducted in order to study and evaluate the effect of carbohydrate spraying on fruit growth and quality of pistachio cv. Kalleh-ghoochi. Carbohydrate mixture was 3% sucrose, 2% glucose with a 0.5% fungicide (Copper Oxcy Cloro) which were applied during different times of fruit growth period of pistachio cv. Kalleh-ghoochi nuts. The experiment was carried out during 1997 season in the Pistachio Collection Orchard of Pistachio Research Institute (PRI) in Rafsanjan. Treatments were arranged in a randomized complete block design (5 treatments with 3 replications). Treatments were applied during fruit growth and high carbohydrate demand including 1) onset of endosperm rapid growth, 2) endosperm competition and onset of embryo rapid growth, 3) time of embryo and cotyledon completion and digestion of endosperm and 4) application in 3 dates as treatments 1,2 and 3. Some quantitative and qualitative fruit characters were measured and compared with control treatment. Results indicated that the best time for carbohydrate application for improving pistachio fruit quality was time of endosperm rapid growth. At this time treatment application improved some nut quality characteristics such as increased shell dehiscence and decreased percentage of blank nuts and fruit abnormalities. The effects of treatments on nut fresh and dry weights, protein percentage as well as absorption of some minerals were not significantly different in compared with control.

In order to study the effects of intercropping on cucumber and tomato and determine the best plant density for these crops, an experiment was carried out for one year (1996) at Behbahan Agricultural Research Station. A randomized complete block design with fifteen treatments and four replications were used. In this experiment cucmber and tomato were grown as pure stads and intercrops in three plant densities: high, medium and low (4.2, 2.8 and 2.1 plants / m2 respectively). Cucumber was grown in combination with 75%, 50% and 25% of tomato. The replacement series technique was used to form the intercrops. According to the obtained results, the optimum plant density for cucumber and tomato were 2.8 plants / m2. Computation of LER (Land Equivalent Ratio) showed that C50T50 (50% cucumber + 50%tomato) and C25T75 (25% cucumber + 75% tomato) combinations in all planting densities were greatar than unity. So, the advantage of intecropping cucumber and tomato were confrimed. Medium planting density of C50T50 combination with mean yield of 40.71 tons/ha and yield advantage of 34% was the best treatments. The differences between qualitative characteristics (percent of dry matter in cucmber and tomato fruits as well as vitamin C content in tomato fruits) in all treatments were not significant.

Effects of four planting dates on four maiz hybrids (SC604, SC647, TWC648 and SC704) were studied using a randomized complete block design in split plot arrangement in four replications for three years (1995-97) in Gorgan. Each hybrid was planted in 4 rows of 10m long. Two middle rows were used for date recording and assessment. According to the results, the highest grain yield of 7.883 ton/ha abtained from hybrid SC704. Hybrids had not significant interaction with planting dates which means delay in the planting, decreased the grain yield in all hybrids. The average hybrids grain yield decreased from 8.626 t/ha to 5.492 t/ha by delaying the planting date from 22 June to 5 August. The grain yield/ear, seed size and number of kernels/row were minimum in 5 August planting datye. The hihest mean grain yield/car, number of kernels/row and number of kernels/ear belonged to the high yielding hybrid, SC704, but this hybrid produced the lowest number of rows/ear (14.8 rows). There were no significant correlation between grain yield and number of rows/ear, but, the highest and lowest correlation of grain yield were with grain yield/ear (r= 0.58) and number of kernels/car (r= 0.30), respectively. Path analysis showed that seed size (p= 0.42) and number of kernels/row (p= 0.27) had the highest and number of kernels/ear (p= 0.03) the lowest direct effects on grain yield.

Olive (Olea europaea L.) is one of the fruit trees which is becoming an important fruit industry at the near future. It seems that olive tree has potential for resistance to drought conditions of semi-arid regions of Iran. So, there is a high production potential for olive tree in many regions of Iran. In this regard a substantial amount of suitable and vigorous rooted cuttings are essential for establishing new olive orchards. This experiment was conducted to study the effect of water stress and deficit irrigation on growth of young olive plants cv. Local Roghani Roodbar. The amount of irrigation water on vegetative growth of two years old olive plants was evaluated. Treatments were 20, 40, 60, 80 and 100% evapotranspiration (ETc). Generally root, leaf and shoot fresh and dry weight, leaf area, number of leaf, plant height, number of shoots, length of shoot and mineral content showed a positive correlation with the amount of applied water. The differences between treatments were significant in various measured characters. Plants received 20 and 40% ETc showed no significant change in their vegetative growth. Plant growth was increased with the other treatments (60,80 and 100% ETc), although this increase in growth was higher in 80 and 100% ETc treatments. In conclusion plants received 80 and 100% Etc showed better performance than the other treatments. In addition, response of plants to treatments were correlated with the time of growing season. Because of lack of significant differences between 80 and 100% ETc treatments in most of measured characters, 80% ETc might be replaced with irrigation based on 100% ETc without any undesirable effects on plants. So, it might be possible to save 20% on irrigation water.

This research was carried out to study cytology and ploidy level of Iranian Hordeum bulbosum genotypes as well as production of interspecific hybrids in crosses with H vulgar for barley breeding program. The collected H bulbosum genotypes 1180, 76063, TN-2-173 and accessions of Firoozkooh, Khorasan, Abyek and Kelardash were used as plant materials. For production of interspecific hybrids, F3 plants from crosses between the spring barley cultivars Trompilo x C.C.89(23216) and C.C.89 x Encldo"s" (23179) were used as females and the H bulbosum genotypes 1180, 76063 and TN -2-173 as male parents. Percentage of seed setting, embryos excised, embryos germinated and plantlest produced from the hybrids were studied. Chi-square test was used for comparisons among the bulbosum genotypes. Cytological studies showed that all Iranian bulbosum genotypes under study were tetrapoid (2n=4x=28). The progenies of interspecific hybridization between diploid Hordeum vulgar (2n=2x=14) and teraploidH. bulbosum (2n=4x=28) were all triploid (3x=21). Statistical studies showed that tetraploid Hordeum bulbosum genotypes 1180, embryos 76063 and TN-2-173 did not differ significantly in seed setting, excised, and germinated embryos and plantlest produced. Considering the possibility of existence of valuable genes in tetraploid bulbosum genotypes such as resistance to pests and diseases as well as environmental stresses, these hybrids seem to be promising for gene transferring into cultivated barley.

Variety Esteghlal is a facultative rapeseed which was obtained with name of Glolal from Swedish Research Institute, Svalof in 1990. This variety is in group of double zero improved varieties that erucic acid in its oil and glucosinolate in its oil-free meal are less than 2% and 30 µ mol g-1 of dry matter, respectively. Preliminary evaluation of this variety along with other rapeseed varieties began at Karaj, Orumieh and Sari Research Stations in 1990/91 cropping season and simultaneously multiplication of its seed initiated in isolated fields. This variety was further avaluated in yield trial at Karaj, Sari, Gorgan, Moghan, Orumieh, Kermanshah and Hamadan Research Stations. However because of frost hazard in cold areas, its cultivation was recommended in areas with mild winters such as Mazandaran, Gorgan and Moghan. Characteristics of the variety are presented in Table 1 (in Farsi text, Page 126). Planting date of this variety in Karaj, Kermanshah, Orumieh and Hamadan was in middle of September, and in Sari, Gorgan and Moghan in middle of October. This variety has moderate tolerance to Sclerotinia disease.

Initially the seeds of this open pollinated variety was received from the University of G6ttingen with the name Cobra in 1990. The adaptability and yield potential of the variety were investigated in preliminary and yield trial experiments under Karaj and Gorgan climatic conditions untill1995. The optimum sowing dates in Karaj and Gorgan regions were the last week of September and second week of October respectively. The cv. Talaye produced average of 2916 kg/ha and 1202 kg/ha seed and oil yields respectively during the year 1990-1994. This yield was a little lower than the cv. Azargol but superier to other varieties and was, therefore, recommended for growing in moderate cold regions as an alternate to cv. Azargol. The average seed and oil yield of this cv. under rainfed conditions of Gorgan region were 2146 kg/ha and 903 kg/ha respectively (Table 1, in Farsi text) superior to other varities and the check "O" cv. Belinda (Raeisi, 1994, 1998). Athough this variety was initetly recommended for Gorgan region, but its widespread use by farmers proved its adaptability for moderate cold regions. This cv. was grown over 100/000ha area during 1998-1999 and showed relative tolerance to Sclerotinia and Alternaria diseases. The Erusic acid of this variety was less than 2% and Glucosinolate content of its meal was less than 30 µ mol g-1 of dry matter (Ahmadi et al., 1996).