NEW FINDINGS IN AGRICULTURE
Year:2010 | Volume:4 | Issue:4 (16)|Papers Count:8

This research was conducted in order to effects of seed priming on germination traits of salt sensitive Triticale line (ET-82-8) under salinity stress conditions. Priming treatments were done by distilled water (Hydro primed) and different osmotic potential (-1, -1.5 and -2 Mpa) of NaCl and PEG6000 for 6, 12 and 24 hours compared with dry untreated seeds. The seeds were raised and dried after priming, then planted in petri dishes. Salinity treatments were applied by different osmotic potential of NaCl (0, -0.5, -1 and 1.5 Mpa) in germinator with 20oC temperature. Factorial experiment was used in CRD with three replications. Results showed that germination rate, root and shoot length and seed vigour significantly increased when seeds hydro primed for 6 hours in no salt stress conditions comparing to no primed seeds, while root and shoot weight and seed germination was not affected. Seed hydro priming for 24 hours negatively affected all traits in both no stress and salt stress conditions. Increased salt stress up to -1 Mpa hydro primed seeds for 6 hours showed better germination rate and vigour than no primed seeds. Seed osmopriming with NaCl and PEG6000 significantly increased length and weight of shoot compare to hydro primed seeds in moderate salt stress (-1 MPa).

This experiment was done to study the effect of sowing date on grain and oil yield, yield components and some characteristics of 6 rapeseed genotypes. It conducted as a factorial on the basis of RCBD with three replications in research field of seed and plant improvement institute during 2005-2007. Sowing dates factor were selected in 3 levels include of 6th September, 16th September and 6th October and cultivars factor were Talaye, SLM046, Okapi, Orient, Licord and Zarfam. The result showed that the sowing date and cultivar effects were significant on all criteria exception the seed numbers in silique and, plant height and biological yield, respectively. Two sowing dates were superior to third sowing date in the point of grain and oil seed yield, harvest index and biological yield. Among yield components, seed numbers in silique and silique numbers in plant were higher in the second sowing date and 1000 seed weight was greater in the first sowing date. Cultivars yield didn’t have significant differences because every one of them was superior to other in the point of one of the yield component. But the oil percentage difference among cultivars caused to create significant differences in the point of oil seed yield among them.

In order to determine best density of silo corn (zeamays L) for good competition with weeds and attainment of acceptable economical yield, an experiment was conducted during 2009 as second cultivation in research farm of Takestan. The experiment was carried out as RCBD in factorial with four replications. Treatments were included density factor (recommended density, 25 and 50% more than recommended one) and weed management (two time weeding, without weeding, nicosolforon herbicide in 2-4 leaved of corn, 1 time cultivation in 20 cm height, two times cultivation in 35 cm of corn). Results showed that corn density and weed management had no significant effect on plant height, diameter of corn with hide, the number of row in corn, the number of seed in row, the number of seed in corn, the grain yield and the weight of 1000 seeds. Corn recommended density together no weeding caused the most diameter of stem, the number of seed in row, the number of seed in corn and corn density 50% more than recommended cause the most biological yield. The density of corn had a significant effect on density and dry weight of Amaranthus blit oides two months after treatments, while weed management had significantly effect in 1% probability level on density and the weeds dry weight in all sampling steps. Corn density by 50% more than recommended caused mostcontro of density and dry weight of Amaranthus blit oides and most decrease in the density and dry weight of Chenopodium album... The most control of dry weight of Amaranthus blit oides and Chenopodium album and most decrease density in Chenopodium album in all samplings most control of density of Amaranthus blitoides in last sampling in response to the treatments, two times weeding and one and two times cultivation was obtained.

In order to evaluating of genetic diversity of sesame genotypes, screening the drought – tolerance quantitative indexes, determining and introducing the drought – tolerance genotypes and also having the economical performance, 24 sesame genotypes including internal and external cultivars were studied in Jiroft in the agricultural year of 2008. The tested genotypes were cultured in two separate experiments (normal and stress, irrigation after 100 and 240 mm evaporation from the basin of class A, respectively) based on RBD in 4 repetitions. In this study, the properties such as length of shrub, number of accessory branches in each shrub, number of capsules in each shrub, number of seeds in each shrub, weight of 1000 seeds, seed performance and the percentage of oil for each genotypes were determined. By using the seed performance in the normal experiment (Yp) and stress (Ys), the drought – tolerance quantitative indexes including (TOL) Tolerance index, (MP) Mean productivity, (SSI) Stress susceptibility index, (GMP) Geometric mean productivity, (STI) Stress tolerance index, (HM) Harmonic mean and (CV) Correlation varieties, were evaluated. The obtained results have shown hat there is a meaningful difference between the different genotypes in the normal and stress conditions and also, by considering the genetic diversity, there was possibility for choosing the drought – tolerance genotypes. The genotypes of JL-13Darab 14 and TS-3, due to the high performance of seeds in the normal and stress conditions and also obtaining the suitable place in the drought – tolerance indexes such as STI, MP, GMP and HM, were accounted as the tolerant genotypes. Analyzing the correlation between performance in the normal and stress conditions and also the drought – tolerance indexes was shown that indices of MP, GMP, HM and STI are the suitable indices for screening the sesame genotypes. In according to the above performance and four indices in two conditions (normal and stress conditions), the best drought – tolerance genotypes of sesame were determined as the genotypes of JL-13 and Ts-3.

To evaluate The planting pattern effects on phonological characteristics yield and yield components of tropical beans genotypes experiment was conducted in Jiroft Islamic Azad University research farm during 2009. The experiment used in split plot design based on RCBD with four replications. Plant arrangements were considered in three levels as one row on the stack with a distance between a plant 10 cm, two rows on the stack with a distance between plants 20cm and three rows on the stack with a distance between plants 30cm, as the main plot and genotypes at three levels (cowpea, cream tepary bean and black tepary bean) as sub plot were studied. Characteristics such as grain yield, straw yield, the number of pods per plant, seeds per pod, and average pod length, plant height, seed weight, and harvest index, number of seeds per plant, biological yield, and changes in dry weight were studied. The trait of black tepary bean with planting arrangement of three rows on the stack with a distance between plants 30cm with the maximum number of pods per plant (20.90) and maximum number of seeds per plant (266.5) and maximum harvest index (46.55%) to black tepary bean with planting arrangement of two rows on the stack with a distance between plants 20cm. Genotypes that studied of the number of pods per plant, seeds per pod, average pod length, seed weight and, number of seeds per plant in the 1% probability level were significant.

To study the effect of sowing date, plant density and different levels of nitrogen on yield and the among of essence in spring safflower an experiment was done in research farm of Arak Islamic Azad University during 2010. Experiment was performed as factorial split plot based on RCBD with four replications. Treatments were selected as two sowing date (10th of May and 10th of June as delayed planting), three different levels of nitrogen (46, 92 and 138 kg/ha based on used urea) and two plant density (400 and 800 thousand of plant/ha). The treatment sowed in 10th of May with 800 thousand plant/ha and 92 kg/ha nitrogen has the maximum essence by 267.431 g/m2. The Minimum essence yield was found in treatment sowed in 10th June, 46 kg/ha nitrogen and 800 thousand plant/ha by 163.54 g/m2. Maximum yield was related to trait with 10th May, 138 kg/ha nitrogen and 800 thousand plant/ha by 3101 kg/ha. Results showed that sowing date of 10th of May has better yield in Arak region in respect with delayed planting and using nitrogen can cause to increase essence.

In order to evaluate grain yield, protein and oil percent in Soybean (Clark cv.) under the condition of drought stress and also efficiency of Bradyrhizobium japonicum strains, the research was performed an experiment during 2003-2004 within split plot design based on RCBD with three replications in the Agriculture Research Institute of Borujerd. The treatment of irrigation was selected as the main plot with three levels of drought stress, namely low stress (85% plant water requirement), medium stress (70% plant water requirement), high stress (55% plant water requirement) and also the plot as complete irrigation as control. The subplot was Bradyrhizobium japonicum strains made use of three stains including, Helinitro, Rizoking, Nitragin and also a level without use of bacteria strain (control). The amount of irrigation water calculated with the help of plant water requirement and the atmometer. In time of planting were inoculated seeds with bacteria strains. And then biological yield, grain yield, grain harvest index and grain hundred weight determined. The results indicated which grain yield was different under two conditions, stress and control irrigations ones. In the optimal irrigation of maximum of grain yield and biological yield produced by Nitragin bacteria strain. In the stress conditions, the efficiency of bacteria strains were different as under low and medium stresses, grain and biological yield obtained by Rizoking bacteria strain; so this strain had a adaptation with drought stress, but in high stress no different within all of the bacteria strains were observed.

In order to study the impact planting season and moisture stress on the yield formation and yield components of spring cultivars of rapeseed an experimental field was performed during 2008-2009 in Qazvin research station, Iran. It was performed in form of Split-plot factorial based on RBD with three replications. The main factor was considered as the growing season condition in two levels including the autumn planting (10/02/2008) season and spring planting (03/02/2009) season. Irrigation was performed at two levels including usual irrigation as control and stop of irrigation when flowering stage onwards and four cultivars consist of RGS003, Sarigol, Hyola401 and Option500 were selected as subplots. In order to calculate traits such as main and sub pod length, the number of grain in main and sub- pod and yield formation. After sampling from different stages of growth parameters measurement, the results showed that tested traits due to field management operations such as growing season and moisture stress are corrected. Results showed that the simple effect of planting and irrigation season on the main and sub-pod length, number of grain in main and sub-pod and grain yield became meaningful and the interaction effect of planting and irrigation season on the main and sub-pod length, and the number of gain in main pod did not be meaningful but on grain number and grain yield in sub pod was meaning. Thus with increasing pod length and number of grain in main and sub pod, grain yield will be increased too.