فصلنامه زراعت و اصلاح نباتات
سال چهاردهم شماره 2 (تابستان 1397)

In this research was conducted to compare three methods of haploid production in hexaploid wheat through chromosome elimination (wheat ×maize cross) for use in the breeding programs. The three methods were A) classical B) detached and C) intermediate or sime-detached. Parental materials were 11 wheat F1 genotypes as female parents and BS572 hybrid as male parent. The traits studied were percentage of seed set, percentage embryo formation and percentage of haploid plantlet production. Among all the three methods, the intermediate C) method was significantly superior to others in which the seed set, embryo formation and haploid plant production were 84.98%, 21.73% and 49.52% respectively. Overall, haploid production from the initial number of pollinated florets was 13.80% in this method Among all the three methods, the intermediate C) method was significantly superior to others in which the seed set, embryo formation and haploid plant production were 84.98%, 21.73% and 49.52% respectively. Overall, haploid production from the initial number of pollinated florets was 13.80% in this method..

This study was conducted with purpose of investigate the effect of drought stress on different growth stages of 20 maize hybrids in farm of Seed and Plant Improvement Institute in 2016. Drought stress levels consisted of four experiments (normal irrigation, stress in vegetative stage, reproductive stress and irrigation interruption as compared to control) in a randomized complete block design. The results of analysis of variance showed that genotypes in terms of traits in each non-stress condition, stress in vegetative stage, stress at reproductive stage and alternate condition have a significant difference at levels of 1 and 5%. According to the results obtained from genetic parameters, in the normal experiment, the number of days to tassel flower initiation, in the vegetative stress experiment tassel branching out number, in the reproductive stress experiment the number of aborted seeds and in the alternate condition days to the drying of the tassel had higher heritability. The tassel branching out number showed the highest phenotypic variation coefficient (77.15) and number of seeds per ear row, the highest genotype variation coefficient (75.6) in normal experiment. Respectively, the number of aborted grains (47.7%) and peduncle outside flag leaf (29.10%) in the vegetative stress test, had the highest phenotypic and genotypic diversity coefficients. The highest phenotypic and genotypic diversity coefficients in reproductive stress test were observed in number of seeds inoculated trait with 45.8% and 37.2%, respectively.

In order to determine the vertical distribution of leaf area index and remobilization of assimilates to grain in mid- and late maturing hybrids of grain corn, an experiment was carried out in Randomize complete block design (RCBD) with four replications in Lorestan Agriculture Research Center in 2014. Average numbers of green leaves in investigated hybrids at flowering stage were 11. Vertical distribution of leaf area index curve was third-order polynomial as bell-shaped with highest leaf area density in the middle of canopy. A third-order polynomial accurately as S-shaped curve described the relationship between cumulative leaf area index (LAI) and plant height at tassel emergence stage. Maximum and minimum of total LAI were achieved from hybrids 4 and 9 respectively, but highest and lowest grain yield achieved from hybrids 11 and 3 (8675.5 and 6237.3 kg/ha, respectively). No remobilization was found between hybrids. Significant and negative correlation between remobilization and LAI (-0.54*), non significant correlation between grain yield and LAI and lack of remobilization indicates a high level of current photosynthesis in the grain filling stage with a severe physiological sink restriction in advanced grain corn hybrids.

Increasing germination percentage and growth indices is important by using methods such as biopriming. The present study aims to investigate effect of biopriming with a number of selected species of native Trichoderma fungi of Iran on yield, germination, vegetative and morphological components of Talash vriety bean seedlings. Also, the effect of induced-mutation by gamma irradiation on the Trichoderma genome and probebly increase in the efficiency of biopriming via using mutated Trichoderma isolates was studied. Experiments with three treatments: control (non-inoculation), Inoculated with wild type Trichoderma based bio-formulation and inoculation with mutants Trichoderma, at the Nuclear Agriculture Research Institute in the form of a completely randomized design with four replications were done. Evaluation of indices (Germination percentage; seedlings, stems and roots length ; their fresh and dry weight and vigor index) based on the ISTA standard method and yield in greenhouse was implemented. Results showed, bean seeds biopriming method with bio-formulations of Trichoderma species (wild type and mutant), plant's yield increased significantly compared to control. Germination percentage of seeds was significantly higher than control in fungal treatments. The important trait of dry weight has also increased compared to control and also had significant difference with control. The length of seedlings of bioprimed with Trichoderma was shorter than the control. Most of the indicators were significantly higher in the one percent level than control. Overally, the results of this study shows, in bean plants, the use of bio-priming seeds with Trichoderma, improves plant growth parameters especially in establishment and its early growth.

In order to investigate the effects of different irrigation methods on yield and some physiological characteristics and activity of antioxidant enzymes of milk thistle (Silybum marianum L.) under using of vermicompost and salicylic acid, a field experiment was conducted as split-factorial based on randomized complete block design (RCBD) with three replicates on Shahr-e-Rey station during 2014-15 growing seasons. Irrigation methods as the main factor were conducted on four levels (including drip irrigation, basin irrigation, furrow irrigation, and alternate middle irrigation) and using of vermicompost on two levels (0 and 15 ton/ha) and application of salicylic acid on two levels (0 and 1 mM) were performed as minor factors. The results showed the highest activity of antioxidant enzymes including catalase, superoxide dismutase, peroxidase, ascorbate peroxidase, and glutathione peroxidase were observed in alternate middle irrigation with the combined consumption of vermicompost and salicylic acid and the lowest them activity in drip irrigation. The amount of malondialdehyde was higher in alternate middle irrigation than drop irrigation and application of vermicompost and salicylic acid simultaneously was decreased amount of malondialdehyde. Also, the highest seed yield and chlorophyll content were observed in drip irrigation with the combined consumption of vermicompost and salicylic acid. The results of this study showed that consumption of vermicompost and salicylic acid has a role in eliminating the negative effects of stress, and can improve the activity of antioxidant enzymes and increase the yield of milk thistle plant.

Seeds that grow in root and stem conditions under drought conditions can be found more quickly and quickly, and in poor environmental conditions, they guarantee higher yields. The experiment was a factorial experiment with completely randomized design with three replications. The investigated factors were 8 levels of fertilizer treatment 1. Control (no spraying) 2. Pure iron (2 per thousand) 3. Pure manganese (2 per thousand) 4. Pure boron (2 per thousand) 5. Boron and manganese (4 In thousand) 6. Iron and boron (4 per thousand) 7. Iron and manganese (4 per thousand) 8. Manganese and boron (6,000) and five osmotic potential levels (0, 2-, 4-, 6-, 8-). Polyethylene glycol 6000 was used to create various osmotic potentials. With the occurrence of osmotic stress, germination speed, germination uniformity, germination percentage and traits related to root and shoot dry weight, root length and shoot length decreased significantly. Germination percentage is related to root length. The roots become green before other plant organs come out of the seed. Consequently, they are subjected to environmental stress before other organs. Therefore, root length trait is a suitable criterion for choosing drought tolerance. The highest root length was obtained in manganese and the least in iron treatment with manganese. Figures with more germination percentage, seedlings longer and more dry matter.

In order to evaluation of agronomical traits, grain yield and grain quality of rice mutants that were tolerant to salinity, one experiment was done in salinity condition the Feridonkenar, as a complete randomly block deign with three replicates in 2017. Ten selected lines from 7th mutant's generation (M7) with standard salt tolerance variety (FL478) and sensitive variety (Taqqing), and three parents ( Tharom Mahali, Hasani and Anbarboo), was used. The recorded traits was: 50% days to flowering, plant height, yield components and grain yield , milling recovery, full grain percent, grain elongation ratio, amylose content and gelatinization temperature. The results showed that deference between genotypes was mostly significant for all agronomic traits and grain quality. The plant height redused in mutants in compared with parents. All most of mutants were earlier maturity than parents. The panicle number per hill was different between 11-14 panicles per hill. The highest thousand kernel weight was devoted to line 1117, and the lowest it was belong to line 221 (23.7gr). The best milling recovery was 70 percent and four mutants had grain elongation ratio more than two in which it was super than parents and checks. The range of grain yield of mutants was different between 2500-7000 kg/ha. The highest grain yield was related to mutant 3218 (7091.5 kg/ha) and the lowest was devoted to mutant 126 (2565.8 kg/ha).

In order to study the effect of winter planting and zinc spraying on yield and yield components of canola (Brassica napus) cultivars, a factorial split plot experiment was conducted in a randomized complete block design with three replications for two years (2014-2015 and 2015-2016 cropping seasons) at the farm of Seed and Plant Improvement Institute Agricultural Research, Education and Extension Organization , Karaj, Iran.. In this experiment, planting dates ( 24th february, 6th, and 16th March) and Zinc factor in two levels , zinc sulfate spray application and non-application of zinc (spray with pure water) were factorial in main plots and spring cultivars including RGS003, Zafar, Julius, Jerry, Zabol 10, Hyola 4815 in subplots.The results of analysis of data showed that the effect of planting date, zinc spray, cultivar and interaction effect of planting date by cultivar on qualitative traits (grain glycosinolate content and fatty acids percentage) in different planting dates and cultivars had a significant difference at 1% level. According to the results, the highest (66.89%) and lowest (66.02%) oleic acid percentage was obtained in Zafar and zabol10 cultivars, respectively The interaction effect of planting dates by cultivar on the glucosinolate content indicated that the lowest glucosinolate content was obtained in Zafar (8.313 mg/g) and hyola4815 (8.567 mg/g) when they were sown on 16 MarchThe results of this experiment showed that delay in planting, decreased amount of palmitic acid, linoleic acid and oleic acid of seed oil, and increased percentage of linolenic acid, erosic acid and glycoinolate content