نشریه نهال و بذر
سال نوزدهم شماره 4 (زمستان 1382)

In order to compare the yield, yield components, oil percent and vegetative characters of canola cultivars in Gonbad, 23 genotypes of spring rapeseed were planted at Agricultural Research Station of Gonbad during 2000-2002. The experiment was a randomized complete block design with 4 replications. The results of combined analysis showed that effect of year, cultivar and interaction between year and cultivar were significant on the number of days from emergence to flowering, physiological maturity, duration of flowering and seed yield at the 1% level. Cultivars Hyola 308 and Syn-3 had the lowest and Dakini had the highest number of days from emergence to flowering and physiological maturity. The interaction was significant because of different temperature in two years of the experiment. The effect of cultivar was significant on number of pods per plant and number of seeds per pod at the 1% level. Hyola 401 Hybrid produced the highest number of pods per plant and Profit and Rafaela cultivars produced the highest number of seeds per pod. The effect of year was significant on 1000 seed weight at the 1% level. Year did not significiant1y affect oil percent, whereas cultivars differed significantly in oil yield. Profit, Option 500 and Hyola 401 had the highest oil percent. The mean of seed yield in the second year of experiment was more than that of the first year. The seed yield in the second year and first year of the experiment were 3658 and 3015 kgha-1, respectively. Hyola 401 hybrid produced the highest seed yield (4479 kgha-1) and oil yield (2042 kgha-1).

The present research was conducted to evaluate effect of grafting two cultivars of greenhouse cucumber (Royal 24189 and Vilmorin), onto figleaf gourd (Cucurbita ficifolia), on their vegetative growth and yield. The obtained results showed that, yield of Royal 24189 cultivar, was significantly higher than that of Vilmorin cultivar. Grafting had an increasing effect on the both cultivar. Effect of grafting on the total number of fruits in both cultivars was different. While in Royal 24189 cultivar there was no difference between grafted and ungrafted treatments, grafted Vilmorin cultivar treatment produced higher number of fruits than ungrafted treatment. Grafting increased root fresh weight which indicates the effect of rootstock (c. ficifolia) on this parameter.

Because grapevine bud number (charge) and cane length affect different factors such as leaf area, plant growth rate, bud break percentage, fruiting shoots percentage, fertility coefficient, number and weight of cluster and fruit quality, therefore in this research, effects of 48 and 72-bud charges together with the cane length having 4, 6 or 8- bud length and their interactions in Bidaneh Sefid cultivar were studied using a factorial experiment in RCBD with 3 replications (each plot as a whole plant). Results showed that increasing the length of cane, charge and their interaction cause to increase the cluster number, fruiting shoots number and fertility coefficient significantly and had no undesirable effects on dimension and weight of cluster. In other words, results show that there is more fruiting in apical buds of cane in this cultivar than first 1-4 buds (which are mostly vegetative) and longe prunning in seedless cultivars appears to be necessary

The AFLP technique was used to investigate genetic diversity and assessing synteny relationships among canola cultivars. A total of 2145 bands were obtained using twenty AFLP primer combinations, which 1058 were polymorphic. Genetic similarity based on Jaccard coefficient ranged from 0.38 to 0.84 with average of 0.61. The dendrogram generated by complete linkage as well as principal coordinate analysis separated the cultivars from each other. Cluster analysis showed that the cultivars could be placed in four groups. These results indicated that the AFLP technique is both efficient and effective tool for determining genetic relationships among canola cultivars.

In order to determine the best sowing date and the best plant density of the local spotted bean (Phaseolus vulgaris L.), cultivar Khomein, an experiment was conducted in two years (1995-1996) at the Khomein National Bean Research Station. A split block design in randomized complete block with four replications was used. Three sowing dates (20 May, 4 June, and 19 June) were allocated in horizontal plots, and five plant densities (20, 25, 30,35, and 40 plants per m2)in vertical plots. The results indicated significant differences among plant densities for number of pods / plant, seeds / plant, 100 seed weight and seed yield. The highest number of pods / plant, seeds / plant and 100 seeds weight were obtained from 20 plants per m2 plots. However, the highest seed yield was obtained from 35 plants per m2 plots (about 3233 kgha-1). In sowing date treatments, plant height and days to maturity decreased with delay in planting. The seed yield was higher in the first sowing date (20 May) than the other dates. The results showed in general, that from desities of 30-40 plants per m2 planting in late May and early June the highest yield will be obtained.

In order to evaluate the effects of conventional, mechanized planting and direct drilling on soil moisture and grain yield of chickpea, this experiment was carried out in RCBD with 4 treatments and 4 replications at Maragheh Dryland Agricultural Research Institute. Field studies were conducted on a clay loam (fine mixed, mesic, veritc calcixerepts) soil on wheat stubble for 3 years (1995-1998). Results showed that there was significant difference in soil moisture content of treatments after planting and before harvesting times. Soil moisture content in direct drilling, after planting and before harvest were 34.75% and 16.25%, respectively. Direct drilling stored soil moisture better than other treatments. The results of combine analysis showed that there was a significant difference in yield in different treatments. Direct drilling and mechanized planting methods produced higher crop seed yield by 891 and 811 kgha-1 respectively. Conventional planting methods (broad casting and covering by diskharrow, broad casting and covering by mould board plow) had the lowest yields (627 and 555 kgha-1).

The method introduced in the present paper is use of biplots obtained from principal component analysis for selecting and screening of genotypes in preliminary experiments considering several traits. Data used in this study were obtained from a preliminary experiment in which 121 sunflower genotypes were tested and 10 superior hybrids were selected. The experiment was carried out for selecting high potential snflower three way cross hybrids in Khoy Aricultural Research Station in 2001. The main objective of this study was to determine if there is any conformity between conventional and PCA method for preliminary selection of genotypes. In the presented method, Based on values of two components that contained high percent of total variance of data and had high correlation with seed yield, oil yield, growth period, seed number per head, seed weight and oil content, each genotype located in a biplot in which two components were considered as X and Y axes. Considering position of genotypes in the diagram, it was found that selected hybrids mainly located at the left half of diagram nearby vectors of seed yield, oil yield, seed number per head and inverse direction of growth period. Logical orientation of genotypes under impression of agronomic traits could be used as effective tool for rapid selection of high yielding and early maturing hybrids. Because of considerable conformity with conventional method and by presentation bright view of genotype's potential, PCA method contributed for selection of 10 superior hybrids and could be used in cultivar development programs.

A study was conducted in Mahidasht Research Station to determine the effect of plant density on yield of late maturity hybrid corn (KSC 704), in 1997and 1998.Row spacing examined was 75 centimeter in four plant spacing in row (21, 19, 16.5 and 14.5 cm), and 60 centimeter in four plant spacing in row (25.5,23.5,20.5 and 18 cm) ranged from 63,000 to 93,000 plants per hectares. Experiments were carried out on randomized complete block design with eight treatments (plant density or planting pattern) in four replications including control treatment. The collected data were analysed statistically based on combined variance analysis on yield components and yield for two years. Effect of year was not significant for most of agronomic characteristics and showing that conditions of two years were the same. Effect of treatments for grain yield was significant at 5% level. According to the results, the highest grain yield of 9680 and 9960 kgha-1 were obtained from 75 cm row spacing in 19 cm plant spacing in row and 60 cm row spacing in 23.5 cm plant spacing in row, respectively. Grain yield of 60 cm row spacing and 75 row spacing were 9337 and 8883 kgha-1 respectively.

Potato early dying (Verticillium wilt), is an important disease all over the world. Both species, Verticillium dahliae and Verticilliumalbo-atrum are prevalent in potato fields of Fars province. V dahliae is more encountered regarding climatic factors. Using tolerant cultivars is an efficient way of control. In this study susceptibility of 19 potato cultivars and 32 selected clones obtained from symptomless plants in the fields, were evaluated toward V dahliae isolate no. 30 in the greenhouse and in field. In the greenhouse, single buds were transferred to the pots and inoculated with 50 ml spore mycelial suspension (the content of one Petri dish in 300 ml distilled water). For the control treatment, single buds were inoculated with sterile distilled water. In fields, whole tubers of the cultivars were inoculated with 50 ml of spore mycelial suspension. The results indicated that cv. Famosa and clone 27 which caused no reduction in the growth period and less than 20 percent yield reduction, were regarded as tolerant. Other cultivars such as Agria, Ajax, Arinda, Binela, Cardinal, Concord, Cosima, Eba, Estima, Herthea, Impala, Kondor, Marfona, Moren, Olivia, Picaso, Primier, Sandra and 31 selected clones were found to be susceptible or very susceptible.

Yellow (stripe) rust is the most serious disease of wheat in Iran. Total yield losses in epidemic years is estimated up to 15% . Most of released cultivars grown under intensive cultivation are usually damaged after few years. The widespread cultivation over thousands hectares of accepted cultivars such as Falat by farmers, known for their adaptation to abiotic stresses in irrigated wheat areas, was perhaps the major reason for stripe rust outbreaks of 1993 in Iran. Attila 50 (Attila CM 85836-50Y-0M0Y- 3M-0Y), released in Iran as c.v. Chamran, is cultivated more than a quarter million hectares. This cultivar has been release six years ago for warm to moderate temperature zone in Iran. This cultivar appeared to be susceptible in Yemen in 2002. Attila is believed to carry Yr27 and 2 or 3 minor genes, had 0-20 MR responses to yellow rust in the adult plant stage in the different parts of Iran. In 2003 the first symptoms of susceptibility of this cultivar was observed in several fields in Kermanshah and Fars providences indicating the appearance of a new race of the pathogen in those areas. At the moment the population of this race is limited, but its spread in future is not far from anticipation. After increasing spores, the new isolate was inoculated on lines of the standard set of stripe rust to determine the race of the isolate. The results showed that the new race was 166E134A+, which is reporting for the first time from Iran. This race has virulence on Yr2 Yr2+Yr7 Yr7+Yr2, 6+ Yr9 Yr2, 9+ Yr24 YrSD YrA genes. To retard and postpone the epidemics of the new race, it is recommended to reduce the grown areas of Charnran gradually, and limit it to dry and warm areas such as Khuzestan, where there is less chance for the disease to be epidemic.