IRANIAN JOURNAL OF AGRONOMY AND PLANT BREEDING
Year:2008 | Volume:4 | Issue:1|Papers Count:9

The Study effects of different level of nitrogen, pyridoxine and their interactional effects on physiology of growth, yield and yield component of seed corn (Zea mays L. var. SC.704) in year 1385. A field experiment was conducted on corn (Zea mays L. var. SC.704) in the form of split plot in three replication, for this purpose of nitrogen in three level (90, 140, 190 Kg/ha) along with pyridoxine in three level (0, 0.01%, 0.02%). the treatment of pyridoxine inoculation with nutriment for this reason, at first step corn seed soaking pre - sowing seed soaking treatment with pyridoxine for 8 hours and treatment of water - soaked seeds were control in lab. the resoults of this study show that nitrogen and pyridoxine have significant effect on the yield and yield components probabely it has positive effect on the process growing of root, lead to in crease absorb of nutriment, especially absorb the nitrogen and it lead to increase the wight of dry material in different organs of plan. In general 0.02 % Pyridoxine treatment and 190 Kg/ha nitrogen gave maximum value for growth and yield parameters. likewise use of prydoxine lead to improvement the situation of indices physiology of measurd growth in this experiment.

Potassium and zinc are two essential elements for different crops such as corn. Corn requirement to potassium and zinc is relatively high. In order to study role of potassium and zinc on grain production and growth parameters of grain corn, a field experiment were conducted in Karaj Soil & Water Research Station with soil K and Zn available 163 and 0.66 mg kg-1, respectively. In this experiment, interaction of four levels of potassium (0, 25, 50 and 75 kg ha-1 K2O), two potassium sources (chloride and sulfate) and two levels of zinc (0 and 10 mg kg-1 Zn as ZnSO4) were compared by factorial in completely randomized block design with three replications. All of agronomic operations carried out based on research recommendations.The results showed that Zn and K application caused significant increases at 1% levels(a=0.01) on grain yield and 5% levels (a=0.05) on the other plant parameters that measure, exception the protein content and percent of grain to wood stalk. The most effects of fertilizer treatments were on grain yield, the numbers and weight of grains in each stalk. Application of 50 kg ha-1 K2O as K2SO4 and 10 kg ha-1 Zn as zinc sulphat at the same time (K2S1Zn1 treatment) caused grain yield, the number and weight of grains in each stalk increases from 6834 kg ha-1, 510 and 177 g per stalk in control to 9167 kg ha-1 633 and 219 g per stalk, respectively. In general, there was no significant difference between to potassium sources.

In order to determine drought tolerance indices and the response of soybean genotypes to drought stress, a field experiment was preformed with 15 soybean genotypes using a split plot in randomized complete block design with three replication in 2006 at seed and plant improvement institute, Karaj. Three levels of irrigation 50 (normal condition), 100 (mild stress) and 150 (severe stress) mm evaporation from evaporation pan were considered as the main plot and commercial and promising varieties as the sub plot. In order to evaluation of genotypes to drought tolerance, 9 indices were calculated for yield in hectare. Results showed that genotypes had different response to normal and stress condition. Also, results of biplots analysis and correlation analysis between indices showed that STI, GMP and MP were most suitable indices. After selection of genotypes A and D area in biplots that in each two conditions which had high yield and low yield, respectively based on three introduced indices in three irrigation condition, genotypes as H301, L5P77, S2494G4, M9 and Hamilton had highest yield and they were resistance to drought stress and genotypes as Baj-Maj, Hy1, Br84bijelina and 9242 had lowest yield and they were sensitive to drought stress. Study of cluster analysis results indicated that genotypes in normal condition had low different and this subject made two groups in this trait. But in mild stress, four and in severe stress five groups were observed, that this is because of stress effects on genotypes and response of them to stress.

In order to evaluation of planting date effect on phenological, morphological and agronomic traits and yield and its components and compare different growing types of soybean, 364 soybean genotypes (35 determinate, 183 Semi determinate and 149 Indeterminate, most of them from 1-4 maturity groups) with 3 planting dates (30 May, 19 June and 10 July) were studied, based on an augmented design with 3 checks (Williams, Zane, Steel) and 6 blocks, in seed and plant improvement institute, Karaj, Iran during 2004 -2005. 17 traits such as days to beginning of flowering, days to complete of maturity, Plant height in complete of maturity stage, number of pods per plant, number of seed per plant, biological yield and seed yield per plant were recorded. The results indicated that number of days to beginning of flowering until days to complete of maturity, Plant height, Number of nod and number of sterile nod in complete of maturity stage were significantly reduced by delayed planting in each growing type but yield and its components were significantly increase from first planting date to third planting date, unexpectedly. Although number of pods per plant, number of pods per branch, number of seed per plant and seed yield of indeterminate genotypes was higher than determinate and semi determinate genotypes at first planting date but number of pods per plant, number of pods per branch, number of seed per plant and seed yield of indeterminate genotypes was lower than determinate and semi determinate genotypes at last planting date, so this result show that determinate genotypes will produce higher yield than semi determinate and indeterminate genotypes providing late planting. The discriminate functions for 3 planting date were also used. Two functions described about 100 percent of variance between data. The discriminate function showed planting dates are in different groups. Days to beginning of flowering, days to beginning of pod, days to beginning of seed, days to full seed, days to beginning of maturity, days to complete of maturity, plant height in complete of maturity stage, biological yield and seed yield per plant were the most important traits in these functions.

In the other to Study of drought stress and Selenium spraying on seed yield and yield components of winter rapeseed (Brassica napus L.) cultivars in Shahr-e-Rey region, An experiment carried out in Split factorial design in the basis of randomized complete blocks with 4 replications in 2006, that Irrigation in two levels: Normal irrigation and irrigation with drought stress when the soil electrical conductivity and Opera and selenium spraying at the beginning of flowering in 3 levels: 0, 16 and 21 mg/ha as sub factor.The results showed that the simple effect of irrigation, selenium and cultivars on seed yield and yield components had significant difference at 1% level. In this case Okapi with 3197 Kg/ha and Opera with 2497 Kg/ha produced maximum and minimum amount of seed yield in stress and non stress condition. Interaction effect of irrigation and cultivars on seed yield and its components had significant difference at %1 level. Normal irrigation in Okapi with 3869 Kg/ha and drought stress in opera with 2176 Kg/ha conducted to maximum and minimum seed yield amount and Zarfam with 2780 showed highest seed yield in stress condition.Interaction effect of irrigation, cultivar and selenium on seed yield had significant difference at %5 level and indicated that normal irrigation and 21 gr/ha selenium spraying in Okapi with 4083 Kg/ha gained to maximum seed yield amount.

In order to identification of superior genotypes for grain yield, 20 advanced genotypes of barely (Hordeum vulgare L.) were sown in two separate experiments under optimum and drought stress condition using Randomized Complete Block Designs with four replications in dry land research station, northern Khoorasan, Shirvan, Iran, during 2005-2006. Data were collected and analyzed for each experiment and combined over two experiments. The grain yield in optimum (Yp) and stress (Ys) condition for each genotype were used to estimate the five drought resistance indices as: tolerance index (TOL), stress susceptibility index (SSI), mean productivity (MP), geometric mean productivity (GMP) and stress tolerance index (STI). The data subsequently used in principal components analysis. Based on bi-plot of the first two principal component scores, genotypes were distributed into four groups. Results showed that genotypes 10, 11, 16, 18 and 19 with average values of 1670 kg/ha were recognized as the best varieties for dry condition. The genotypes 12, 13, 14, 17 and 20 with average values of 1300 and 1974 kg/ha for Drought and normal conditions, respectively introduced as the best genotypes for cultivation for both environments in semi arid regions. Genotypes 1, 5 and 15 with average values of 1450 kg/ha had moderate production for normal conditions. Distribution of genotypes based on the first two component scores was in agreement with Grouping of genotypes by Duncan means comparison method.

In order to study effect of nutrition elements application on agronomical characters of maize hybrid (KSC.704) under water deficit stress at different growth stages a field experiment was carried out in the Agricalture Research Station of Islamic Azad University, Arak Branch, Iran in 2006-2007. Experimental design was split plot factorial based on randomized complete blocks design with four replications. Four irrigation levels including: optimum condition (L1), water deficit stress in stage V8 (L2), water deficit stress in stage of blister (L3) and water deficit stress in stage of grain filling (L4) were assigned to main plot, and combination of selenium (with and without using) and microelements (with and without using) were randomized to sub-plots.Results showed significant differences on plant height, ear height from ground, ear weight, cob weight, ear length, biological yield, grain yield and biological water use efficiency under water deficit stress between treatments. The lowest effect of water deficit stress on grain yield and biological yield was in vegetative stage. Also the highest water use biological efficiency obtained from this stage. However using of selenium increased all agronomic traits but effect of selenium on measured traits was non significant. Interactions of water deficit stress and selenium on grain yield, biological yield and water use biological efficiency at 1% probability levels was significant. Using of selenium at different growth stages under water deficit stress increased this trait as compared without selenium. The highest grain yield (8159.330 kg ha-1) and biological yield (16728.76 kg ha-1) obtain from water deficit stress at vegetative stage, with selenium and without micro element that with control (non water deficit) stress, without selenium and micro element wan non significant.

In this study, after propagation and producing tissue-culture clones obtained from seed population Jot 18 (pollinator tetraploid resistant to bolting), these clones were incubated in cold condition of 4-7oC for 12 and 15 weeks, and then were transferred to the greenhouse with 20oC and percent of bolted plants was determined. A randomized complete block design in three replications was used for statistical analysis. Percentage of bolting was calculated in 1 and 2 weeks after cold treatment duration. The result of 12 week incubation at cold condition showed that genotypes have significant differences after one or two weeks at 5% and 1% level respectively. The result of 15 week incubation at cold condition showed that genotypes have significant differences after one or two weeks at 1% level. Results showed that in two cooling period, genotypes B29 and B16 are tolerant and susceptible to bolting respectively. Use of colons having same genotype, resulted in increasing of selection accuracy of resistant genotypes. In this study for decrease need cooling period, for screening tolerance genotype to bolting in sugar beet used GA3 treatment. For this, three concentrations 0, 10 and 50 milimolar GA3 were inoculated for six times onto shoot apices of seedling of one-month cold pretreated. Factorial experiment in randomized complete block design was used in three replications. Percentage of bolting was calculated in five times at one-week interval after final inoculation step. The results of second week were used for screening of bolting tolerant plants. A statistical level was 1% and result of the second week note- taking indicated that GA3 and genotype effects are significant at 1% level and GA3 genotype interaction did not have significant differences. As a result, Genotypes was classified in three groups: susceptible, semi tolerant and tolerant. As a result 50 concentration milimolar had more effective on bolting sugar beet and breeder can use GA3 as a substitution for part of cold duration and reduce breeding time for bolting screening and increase selection efficiency.