JOURNAL OF AGRICULTURE
Year:2007 | Volume:9 | Issue:1|Papers Count:9

To determine the general and specific combining ability of the parental lines, five restorers and four male sterility lines were selected as lines and testers respectively. Nine parental lines were crossed in a Line x Tester crossing system in year 2005 and the eight F1 hybrids and their six parents in Randomized Complete Blocks Design (RCBD) in two replications for yield, yield components and major qualitative characters. The effect of GCA was negative and significant for grain yield in line No.2 (Sepidrood), and in line SA14R, it was positive and significant for grain yield. The effect of SCA was positive and significant for grain yield in four hybrids of IR58025A/IR62030R, IR79124A1SA13R, IR79124A ISA14R and SA15A /Sepidrood. Two hybrids (IR79124A1 SA13R and IR79124A/SA14R) had the highest grain yield with 10.4 and 11.5 t/ha respectively. These combinations were recommended for hybrid seed production in of Gilan province.

In order to study the effect of water deficit effects on agronomic characteristics of sunflower hybrids, three separate experiments were conducted as randomized complete block design with three replications at the research field of seed and Plant Improvement Institute - Karaj. The first experiment conducted at optimum conditions and plants were irrigated after 60 mm evaporation from evaporation pan at germination stage till end of growing period, whereas the second and third experiments were irrigated after 120, 180 mm evaporation from evaporation pan, class A, respectively, and were considered as water deficit conditions. The results showed significant effects of water deficit on 75 percent flowering stage, 1000 seed weight, seed number per plant, seed yield, productivity effort, harvest index and seed oil content. Sever water deficit caused the decrease of seed yield to 500 Kg ha-1 (83 percent reduction) which was due to decrease of 1000 seed weight (50 percent) and seed number per plant (54 percent). Also, Allstar produced the highest yield in medium and severe water deficit and the Mehr was superior to other hybrids in normal condition.

Rice is one of the most important staple cereals in Iran and has a main role in providing the food security. Harvesting by hand postpone the rice harvesting stage, and facing late season rainfall, an increase of yield losses during harvesting. To determine the most suitable harvesting method in Gilan, three different harvesting methods (by hand, harvester and combine) were considered as treatments and four different cities as blocks. The effective farm capacity, percent of total losses, percent of harvesting losses, number of workers and harvest costs were determined. The difference of percent of total losses and other factors were significant in different harvesting methods. Effective farm capacity in harvesting with harvester was more than other methods. Harvesting by combine had the lowest losses percent (1.92%). In harvesting by hand 98.3 percent of harvesting costs were related to harvesting and collecting of crops. In lands that have been consolidated, using combine and in small scale the use of harvester are recommended.

Genetic manipulation and selection of favorable somaclonal variant from callus culture are supplementary tools for plant breeding. Immature embryos are the most frequently used explants source for in vitro culture. Response of 25 wheat (Triticum aestivum L.) genotypes to callus induction and plant regeneration from immature embryo culture was evaluated under in vitro condition. Basal MS medium supplemented with 2 mg/L 2, 4-D and 0.1 mg/L kinetin was used for callus induction.Callus induction rate and callus growth rate were used as callus induction criteria of cultivars derived immature embryo culture. Response of cultivars to regeneration from callus was evaluated using the percentage and rate of plant regeneration. Average percent of callus production ranged from 46 to 95 percent in "Sholeh" and "Cross Sorkh Tokhm" cultivars, respectively." Cross Sorkh Tokhm" in view point of callus induction and "Alvand" with considering the regeneration from callus at the shortest time, were ranked as the superior genotypes. Considering the total plants regenerated from the cultured immature embryos, "Alvand", was ranked as the superior genotypes.

This study was conducted during 2003-2004 and 2004-2005 growing seasons at Shirvan Agricultural Research Station, to evaluate the performance of eight winter chickpea seed lines. The experiment conducted in randomized complete block design with four replications. During the growing season, date of flowering, plant height, number of pod per plant, number of seed per pod and date of maturity were recorded. After harvesting, 100 seed weight and seed yield were measured. There were significant yield differences between genotypes. Combined analyses showed that line SEL 93TH 24477 with 958.4 kg/ha had the highest seed yield mean. The line ILC 8262 with 524.1 kg/ha had the lowest seed yield.

Six cultivars of hexaploid wheat (Hyrmand, Shiraz, Pishtaz, Marvdasht, Mahdavi, Roshan (susceptible check) and M-79-6) in subplots, and three seed treatments: I1- seed without treatment; I2-seeds artificially infected with bunt spores in 5/1000 ratio and I3-seeds treated with Carboxin thiram FS in main plots of a split plot trial within a RCBD with three replications and 3 locations of Karaj, Kermanshah and Neishabour were studied. Bunt efected was measured using spike counting for every experimental plot. The data transformed to Arc Sin [X1/2] and the means compared. In all locations seeds with bunt spores treatment produced higher percentage of bunt infection. The varieties Roshan, Mahdavi, Marvdasht and Shiraz showed high rates of bunt infection as susceptible varieties. The Hyrmand, Pishtaz and M-79-6 showed trace infection and designated as resistant varieties. The cultivation of M-79-6, which showed a high level of resistance to common bunt in temperate polluted areas, could lead to control disease and decrease operating cost of seed treatment.

Cyanogenesis in Prunus species produces cyanogenic glycosides such as monoglycoside Prunasin and digelicosede amygdalin. Despite the mechanism of almond bitteruess inheritance has been known, biosynthesis cycle of cyanogenic compounds among different genotypes is still unclear.Total soluble proteins of fruits was extracted from collected sweet and bitter almond genotypes and was studied using westeru immune blotting assay with Mandelonytril glycosidase and related polyclonal antibody, and products of this enzyme was studied by HPLC. Results showed that all of bitter and sweet genotypes had the ability of enzyme synthesis in the fruit and it is produced since mid stage of fruit development. Only bitter genotypes kept synthesis the enzyme and it was suppressed for sweet ones. The HPLC analysis of metabolites synthesized by the enzyme showed that the amount of cyanogenic content of bitter genotypes was much more than the sweet ones and merely in bitter genotype seeds prunasin content was reduced while amygdalin content was gradually increased. This means bitter genotypes could accumulate amygdalin in their seeds.