نشریه نهال و بذر
سال بیست و چهارم شماره 2 (تابستان 1387)

A field experiment was conducted to study the effects of planting date and pattern on grain yield of new corn hybrid (KSC 700) in Islamabad Agricultural Research Station for two years (2004-05). A randomized complete block design in split split plot arrangement with three replications was used in this study. Three planting dates (25 April 5 May and 15 May), three row distances (55, 65 and 75 cm) and three plant densities ( 65000, 75000 and 85000 plants/ha) were assigned to main plots, subplots and sub-subplots, respectively. The results showed that the best planting dates were 25 April and 5 May and the best row spacing was 65cm. Grain yield of 65 cm treatment was higher than those of the other row distances (55 and 75 cm). The best plant density was 75000 plants/ha. The highest grain yields were obtained in treatment combinations of 65 cm row spacing and 75000 plants/ha with 13388 and 12838 tha-1, in planting dates 25 April and 5 May, respectively. Therefore, planting of late maturing hybrids in early May with 70000-75000 plants/ha in 65 cm row spacing can be recommended for moderate regions of Kermanshah province.

Septoria leaf blotch of wheat (Septoria tritici) is one of the most important diseases of wheat in the world. To detemine yield reduction caused by this disease and the effects of infection in different growth stages on yield and yield components in three wheat cultivars, a field experiment for two years (2003-2004) was carried out using a factorial design in form RCBD with four replications. Artifical inoculation at different growth stages including tillering, stem elongation, flag leaf opening and ear emergence were levels of a factor and cultivars Tajan, Zagros and Kouhdasht were levels of other factor. A treatment without infection was considered as check. Grain yield, number of ears per squar meter ,number of kernels per ear and 1000 kernels weight were measured. The results showed that the effects of different stages of infection on grain yield, 1000 kernels weight and number of kernels per ear was significant, but on number of ears per square meter was not . The extent of yield reduction differed on wheat cultivar and infection at different stage. In this experiment, yield reduction were recorded from 9.07 to 28.95 percent .Daily yield reductions in cultivars Tajan ,Zagros and Kouhdasht assessed 0.30, 0.24 and 0.25 percent and total yield reductions were 28.95, 26.67 and 24.69 percent, respectively.

In order to determine the best cultivar and planting date of rice in Khorramabad area, this study was conducted in RCBD as split – plot with four replications in 2003 and 2004. Main plots were four planting dates (April 14, April 23, May 3 and May 13), and three cultivars (Domsiah , Binam and Hashemi) were used as subplots. Results of analysis of variance showed that the effects of planting date and cultivar and planting date × cultivar interaction on seed yield was significant. Domsiah cultivar with 2985.2 kgha-1 in second planting date (April 23) had more seed yield than others. Early and delayed planting dates decreased yield, because of short vegetative period in early planting and high temperature during flowering period in delayed planting date. Planting of Domsiah cultivar in second planting date (April 23) can be recommended for Khorramabad condition, because of its long growing period and phenological stages in optimum temperature.

In order to study the effect of different crop rotation systems on wheat grain yield and some soil properties, this experiment was conducted with seven rotation treatments in a randomized complete block design with four replications in Darab Agriculture Research Station. The experiment was repeated in two rotation frequencies: the first from 1999 to 2002 and the second one from 2002 to 2005 with the same crop treatments. Cropping systems were included 1. broad bean (Vicia sativa L.), corn (Zea mayse L.), chick ling vetch (Vicia villosa L.), and wheat (Triticum aestivum L.) (CS1) 2. clover (Trifolium sp. L.), cotton (Gossypium hirsutum L.), chick ling vetch, wheat (CS2) 3. broad bean, corn, sugar beet (Beta vulgaris saccharifera L.), wheat (CS3) 4. cotton, wheat, cotton, (CS4) 5. corn, wheat, corn, wheat (CS5) 6. wheat, canola (brasica compestris L.), wheat (CS6) 7. wheat, wheat, wheat (CS7). At the end of each rotation frequency, wheat grain yield and its components, soil organic carbon, phosphorous, potassium and bulk density was measured. At the end of second cropping cycle core index of soil different layers was also measured. Results of the experiment showed that CS2 had the highest amount of wheat grain yield in the first rotation frequency, without any significant difference with CS8, CS6 and CS4. The lowest wheat grain yield was for CS5 and CS3, respectively. In the second rotation frequency, wheat grain yield of CS6 was significantly higher than those of other crop systems, and the lowest was for CS5. The higher wheat grain yield of superior cropping systems such as CS2 and CS6 was due to higher kernel weight, more spike number per unit area and more kernel number per spike. The lower O.C. quality, lack of any follow and high nutritional requirements in CS5, resulted in lower wheat grain yield. Some soil chemical and physical properties, including O.C, P and K was also increased in high yielding cropping systems such as CS2 and CS7 in the first rotation frequency and CS6 in the second rotation frequency. Finally it could be concluded that presence of clover as a legume green manure in both short and long-term cropping cycle and canola with summer follow in rotation with wheat in long-term cropping cycle could result to increasing of wheat grain yield.

To assess the effects of microelements on quantitative and qualitative characteristics of 704 silage corn, an experiment was conducted in Khoy Agricultural Research Farm during 2003 and 2004. The experiment was arranged in split plot based on complete randomize block designe. Three foliar application stages T1: stem formation, T2: tasseling and T3: stem formation + tasseling, were considered as the main plots, and eight fertilizer application types, F1: no feritilizer, F2: iron, F3: zinc, F4: manganese, F5: iron + zinc, F6: iron + manganese, F7: zinc + manganese and F8: iron + zinc + manganese, as subplots. The results of mean comparison of different agronomic traits indicated that the highest dry and fresh matter yields, 58.60 and 18.34 tha-1, respectively were obtained from T3 treatments. Fertilizer spraying time affected some agronomic traits such as plant height, stem diameter, leaf number, stem dry weight, ear dry weight, protein and ash percentages. F8 treatment produced the highest dry and fresh matters, 20.18 and 65.86 tha-1, respectively. Fertilizer type had significant effects on all agronomic traits except on leaf number. Based on the btained results, foliar application of Fe, Zn and Mn at stem formation and tasseting stages can be recommended for increasing yield and improving qualitative features of 704 silage corn n Khoy region.

In order to evaluate the effects of irrigation regime and row spacing on seed yield of alfalfa cultivar Baghdadi, this experiment was conducted at Safiabad Agricultural Research Center Farm 2002 to 2004. The soil of the experiment site was silty clay loam.The experiment was arranged in a split plot based on a RCBD. Main plot was allocated to irrigation regimes based on evaporation from pan evaporation(including irrigation after 100,150,200 and 250mm evaporation from pan) and sub plot was allocated to row spacing( including 50,60 and 75 cm). The results showed that there were significant differences for yield and water use efficiency among irrigation regimes. Irrigation after 250 mm evaporation from pan had higher seed yield and WUE. The row spacing of 75cm with higher seed yield (178.7 Kgha-1) and higher seed germination (80.5%) was superior to other row spacings. The significance of years effect for most of the traits indicated the difference in changes of these traits in different years after alfalfa establishment.

In order to assess and compare the potential forage production of Crimsonclover with other clover species in different planting dates, an experiment was carried out in split plot arranged in a randomized complete block design with 12 treatments in four replications in Karaj during 2003-2005. In this study pkanting dates were considerd as main plot in four levels (d1: 23 Aug., d2: 6 Sep., d3: 23 Sep. and d4: 7 Oct.) and clover cultivars as subplot in three levels (v1: Crimson clover, v2: Berseem clover and v3: Persian clover). The results of combined analysis of the experiment demonstrated that effects of year, planting date, year × planting date, species, year × species, planting date × species and year × planting date × species (except dry matter yield) were significantly different for fresh and dry matter yield. Mean comparison of planting dates and cloverspecies showed that planting date d1 with 70.20 tha-1 fresh yield, 13.23 tha-1 dry matter yield, and Persian clover with 83.40 tha-1 fresh yield (the same group with Berseem clover), 15.23 tha-1 dry matter yield were the best treatments. Meanwhile, mean comparison of the interaction of planting date × species showed that d3v3 with 90.21 and 18.82 tha-1 fresh and dry matter was the best treatment.

  Lilium ledebourii (Chelcheragh lily) is a unique species of Lilium genus that is native of north Iran. This study was conducted to investigate the bulblet regeneration of microscales of Chelcheragh lily in vitro conditions and to examine the effect of growth regulators benzyladenine (BA) and naphthalene acetic acid (NAA) in different concentrations. Solid MS medium with three concentrations 0, 0.01, and 0.1 mgl-1 of BA and NAA was used. The experimental design was a 3×3 factorial. Results showed that microscales had good regeneration potential of bulblet, especially when growth regulators used in suitable concentration. The highest number of bulblets and roots obtained in 0.01 mgl-1 BA and 0.1 mgl-1 NAA. Some of regenerated bulblets produced scale leaf directly by increasing the concentration. This character affects negatively bulblet regeneration of L. ledebourii. The results of the present study showed the possibility of micropropagation of L. ledebourii by microscales. Considering the lack of plant material and low vegetation of this plant in natural habitat, these results may find practical application for propagation of this rare plant.

In order to study the kind and rate effects of vermicompost in pot media on Ficus benjamin growth, an experiment was carried out in the greenhouse of Flower and Ornamental Plant Research Station of Lahijan for two years (2003- 2004). This experiment was implemented in factorial based on randomized complete block design with two kinds of vermicompost (vermicompost of cow manure and vermicompost of cow manure + saw dust) in five levels (0, 10 ,20, 30 and 40%) and three replications. These materials were substituted to peat in peat + perlit media (2 : 1 volume %) with respect to the kind and rate of vermicompost, and transferred to 4 liter pots. Results showed that, the effect of cow manure + saw dust vermicompost on shoot and dry leaf weight, dry leaf weight, dry shoot weight and Cu of media was more than cow manure vermicompost. The vermicompost at the rate of 20% significantly increased the shoot and fresh leaf weight, shoot and dry leaf weight and dry leaf weight compared to control. The effect of 10, 30 and 40% vermicompost on shoot and fresh leaf weight, shoot and dry leaf weight, and dry leaf weight were not significant. With respect to the high EC in media of 40% vermicompost and high cost of peat for potting media, application of 20% vermicompost could be economical.

In most of the developing countries, legume plants are the main supply of protein. Since some of these crops are adapted with dry land farming, but their yield potential is almost low. To access high yielding lines in northwest provinces of Iran, an experiment was conducted with 36 chickpea lines in 2003-2004 cropping season in 6 × 6 squared lattice in Zanjan, West Azerbaijan (W.A) and Kurdistan provinces. During the experiment, traits such as days of flowering, days of maturity, plant height, 100 seed weight and yield were recorded. After separate analysis of variance, significant differences were found in the yield of studied lines. For Zanjan line no. 26, for W.A. line no.32 and for Kurdestan line no.30 were selected. For location results, experimental data were analyzed through combined analysis of variance with SAS 8. Significant differences were found among genotypes and genotype × location. The mean data over 3 locations was calculated and in addition to simple correlation, these coefficients were partitioned to direct and indirect effects. PCA analysis extracted two components which totally explained 77.23 percent of observed variations. According to this, among the traits, days of flowering and days of maturity had the largest direct effects on yield. Then with cluster analysis, studied lines were classified into 3 groups. Cluster 1 members had the most genetic distance with cluster 3, therefore considering the purpose, selection of lines from these clusters as parents for hybridization, complementary traits of parents and their maximum variations can be used in breeding programs.

A breeding hexaploid line named Bloyka (ICW84-0008-013AP-300L-3AP-300L-0AP) was introduced to Iran through international nurseries RBWYT-FA and RBWON-FA from International Center for Agricultural Research in the Dry Areas (ICARDA) in 1996 and evaluated at three research stations of temperate zone (Karaj, Islam-Abad and Zarghan). Due to its superior grain yield over check cultivars (7.014 tha-1 vs. 6.986 tha-1 of Mahdavi in Karaj, 8.246 tha-1 vs. 8.002 of Mahdavi in Islam-Abad and 8.111 tha-1 vs. 8.222 of Marvdasht in Zarghan) it was selected and forwarded to advanced trials. This line was tested in advanced trials of temperate zone breeding program during 1997-2000 and due to its qualifications including resistance to stripe and leaf rusts it was considered to be included in adaptation trials. Therefore as an elite genotype (encoded as M-79-7) this line was investigated in adaptation trial in 9 research stations of temperate zone along with check cultivar Marvdasht during 2000-2002. Based on results of two cropping seasons this line produced 6.914 tha-1 grain yield in average in comparison to 6.521 tha-1 of Marvdasht. This line with mean rank of 6.5 and standard deviation of rank equal to 4.8 was one of the most stable genotypes of investigated germplasm set. Drought tolerance of M-79-7 line was also assessed under water deficit conditions compared to Pishtaz check cultivar for irrigated farms and Sardari, Azar-2 and Cross of Alborz cultivars for rain fed conditions and it was found to be partially tolerant to terminal drought. In respect to disease resistance its reaction to a newly spread race of stripe rust in Zarghan research station was 25MR against 80MS, 80MS and 30MR/M for check cultivars Shiraz, Marvdasht and Pishtaz respectively. Bread making quality of M-79-7 was assessed to be moderate to good based on its 11% grain protein content, 83.5 kg hectoliter weight, 29 ml Zeleny sedimentation volume and 54 degrees of grain hardness. The high molecular weight glutenin subunit genotype of M-79-7 line was 2*, 7+8 and 2+12 for three loci of Glu-A1, Glu-B1 and Glu-D1 respectively. Validation trials in farmer's fields confirmed this line as a qualified genotype to be released as a new irrigated bread wheat for temperate regions of Iran.

Pegah is a new forage sorghum cultivar, improved in Iran. It is derived from progenies of a cross made between Early orange (Farian) and LFS56 (Local selected germ[lasm) cultivars. Its improvement took 15 years from crossing up to releazing time. All selections and evaluations were made in SPII and its associated research centers in Iran. Pegah is a pure line variety and its seed production is the same as other self fertilization crops. Green fodder and dry matter yield of pegah in 6 locations for three years were 128.38 and 23.52 tha-1 respectively which were 42.28% and 46.82% higher than those of check cultivar Speed feed. Protein contents of Pegah cultivar is 12%. Maximum green fodder and dry matter of pegah cultivar were obtained in planting densities of 208 and 287 thousand plants per hectare. As an example in Karaj at 208 thousand plants per hectare, it produced 156.39 and 29.32 tha-1 green fodder and dry matter, respectively. As an other aspect, Pegah cultivar has a high contents of sugar in stem, and it is a sweet sorghum cultivar too.