فصلنامه زراعت و اصلاح نباتات
سال ششم شماره 4 (زمستان 1389)

Squash is one of medicinal plants that its juice is effective in remedy of cyst illness and increase of body tolerance for disease ingredient. In order to evaluation of distance cultivation effects and ethylene spry on fruit and seed production in squash, an experiment as split plot design on base of randomized complete block design was conducted in the field with 3replications in spring and summer of 2007 and 2008. This research was conducted in agricultural research farm of Islamic Azad University of Shahrekord. The factors were three dose of ethylene (0, 50 and 100 ppm of 2-Chloro-ethylphosphonic acid) and three density of planting (100×50 Cm, 150×50 Cm and 200×50 Cm). Due to prevention of infection between different dose of foliar application of ethylene and convenience of conduction, dose of ethylene was spread in main plots and densities of planting in subplot. Each replication included three main plots (every main plot had three subplots): therefore whole experiment had 27 plots. Evaluated characters in this research were seed yield and yield components including number of fruit per plant, and number of seed per fruit, 100-seed weight. Although the combinations of 100ppm ethylene×100×50cm and 0-ppm ethylene×100×50cm made the most number of fruit in area but the most mean of weight of fruit, mean of weight of fresh seed made by 100ppm ethylene and 200×50cm density. Results showed that 100ppm of ethylene and 200×50Cm density was the best combination, also correlations between weight of fruit, weight of seed, number seed per fruit were positive, and between weight of fruit and number of fruits were negative.

Reducing of drought damage in plants by using of Bio fertilizers as plant growth promoting bacteria, silicic acid and amino acids and improving physiological parameters and thus raising the level of plant yield in arid and semi arid areas are emergency management for drought control agriculture and also in wheat agronomy. irrigation factor at two levels includes {a1 first level: Control, a2 second level: cut irrigation after flowering stage} anol the second experimental treatment at the five levels includes {b1 first level: control, b2 second level: seed inoculated with bacteria (Azospirillum, Azotobacter, Pseudomonase), b3 third level: seed inoculated with bacteria (Azospirillum، Azotobacter، Pseudomonase) and sprayed silicic acids, b4 fourth level: seed inoculated with bacteria (Azospirillum، Azotobacter، Pseudomonase) and sprayed amino acids, b5 fifth level: seed inoculated with bacteria (Azospirillum، Azotobacter، Pseudomonase) and sprayed silicic acids with amino acids} in randomized complete blocks design with four replicates using analysis of split plot. Analysis of variance showed that the Antioxidant enzymes in the 1 percent level is significant, so that the highest levels of super oxide dismutase, catalase and glutathione peroxidase related to cut irrigation after flowering. effect second experimental treatment that the Antioxidant enzymes in the 1 percent level is significant and highest levels of Antioxidant enzymes related to control and lowest levels Belonged to seed inoculated with bacteria and sprayed silicic acids with amino acids, while the interactions between level irrigation and the second experimental treatment showed that the lowest levels of super oxide dismutase, catalase and glutathione peroxidase belonged to normal irrigation and seed inoculated with bacteria and sprayed silicic acid with amino acids (235, 86. 3 and 54. 7 U/g protein), respectively. The results of this experiment can be inferred that the plant growth promoting bacteria associated with spraying silicic acid and amino acids in increased tolerance to drought stress in wheat because of lower production resulting the biochemical biomarkers there by reducing the oxidative damage caused by active oxygen speices that are under drought stress is created the plants spend lessenergy to produce antioxidant enzymes to counteract the biochemical biomarkers.

In order to evaluate the application of different levels of nitrogen and plant densities on agronomical traits of canola a split plot experimental design based on randomized completely block design (RCBD) in three replications was conducted during 2005-2006 cropping season. The canola plant was cultivated in paddy field in rotation with rice. The main plot consisting 4 levels of nitrogen fertilizer application: 0 (control), 46, 92 and 138 kg nitrogen and the sub plot comprising: 3 different levels of plant densities 65, 80 and 95 plants/ m2. The results drive from the experiment showed that number of sub-branch, pods in main stem and secondary stem, total number of pods per unit area, number of seed per pod, oil and seed yield all increased with an increase in amount of nitrogen application at 138 kg/h significantly. Maximum seed yield (3134 kg/h) gained at 80 plants/m2, therefore it was concluded that application of 138 kg/h at the density of 80 plants/m2was the most suitable treatment for increased canola seed yield in canola plant in paddy field at the situation of the experiment.

In order to determination plant density rice cultivars with machine transplanting in Tonokabon Rice Research Institute of Mazandaran in 2009.This experiment laid out as split plot in a randomized complete block design with 3 replication. The main plots were planting space with four (12×30, 14×30, 16×30 and 18×30) Cm and sub plots were rice cultivars (Shiroodi, Kados, Hashemei and Deylamani). During growth stage traits, plant height, Fertile tiller, panicle length, number of grains (filled, unfilled and total) per panicle, 1000-grain weight, biological and economical yield, harvest index and grain yield were measured. Anova showed non significant difference for all characters (except filled and total grains) measured. Effect of cultivars on filled and total grains was significant at 0.05 probability level, effect on plant height, Fertile tiller, panicle length, unfilled grains, 1000-grain weight, biological and economical yield, harvest index and grain yield was significant at 0.01 probability level. The highest grain yield (5787/3 kg.ha-1) was obtained in 18×30 cm planting space. The greatest grain yield (7374/1 kg.ha-1) was obtained for Shiroodi cultivar. Finally, according to the results, 18×30 cm planting space and Shiroodi cultivar was recommended.

In order to evaluate the interaction of rice genotypes to salinity Stress, responses of 4 rice genotypes were assessed to 4 salinity levels (0, 4, 8, 12, ms/cm) through a split plot experiment in yield stage by CRD in 3 replications in green house plots. In this experiment was carried out 4 genotypes with 4 salt levels (0,4,8,12 ms/cm). Varieties that were used contain: PSBRC88: international salt tolerant, IR58025A/ IR60819R: salt susceptible, Gerdeh and Anbarboo: indigenous varieties. when seedlings were 21 day old, salinity treatments were carried out. characters such as: time of flowering to ripping, plant height, number of effective tiller, main panicle length, length of another panicles, weight of crucible, weight of straw, distance of biggest panicle knot to flag leaf sheath, number of empty and filled grain and total biomass were measured. The salinity had a significant efficient on those characters. Effect of genotype × salt had a significant effect on 8 character with the exception of plant height, number of effective tiller, and length of another panicle. weight of crucible of PSBRC88 and IR58025A/ IR60819R almost was decreased 53 % and 73% to control respectively. Anbarboo after PSBRC88 was selected as a more tolerance variety.

Using plants for extracting metals have been discussed as a promising alternative in extracting extra metals from soil and water. The aim of plant extraction is therefore decrease in metal concentrations in contaminated soils for which the plant tolerance is of high importance. On this basis in order to predict and understand the ability of alfalfa in absorption and remediation of heavy metalslead and copper and the antioxidant behaviors of Superoxide dismutase and Catalase to such metals an experiment was conducted with alfalfa (Medicago sativa) cultivar Hamedani in the fall of 2009. Four levels of lead (Pb(NO3) 2) 0, 200, 400، 800 and four levels of copper (Cu(SO4) 2) levels 0, 150, 300 450 mg/kg soil were used. The experiment was carried out in factorial form as completely random design with 4 replicates. Results suggested more absorption of lead and copper in aerial parts than root system. The measured values of lead and copper transmition factor were clearly indicated more lead and copper absorption in aerial parts than root system. Copper was absorbed more in aerial parts than lead. Results for enzymes Superoxide dismutase (SOD) and Catalase (CAT) assay demonstrated with the increase in the level of lead and copper the antioxidant behaviors of the two enzymes increased significantly (P<0. 01).

A fild study was conducted at farm of Damavand in 2006 to find out the effects of different levels of nitrogen and potassium on oil and protein percent of canola(Brassica napus). A randomized complete block deisgn experiment was carried out with four replication that consisted of ten levels the results indicated that this levels had significant effection on protein, oil and 1000 seed weight on %5 level. But on the grain yield had no significant effectt. Increasing the nitrogen and potassium levels protein percent increased, but increased between N250K150 and N250K100 levels was higher all different fertilizer levels. Intraction of nitrogen and potassium fertilizer changed on oil percent so with almost increase of N on N150K100 levels in maximum. Meanwhile different fertilizer levels on grain yield and 1000 seedweight on the N200K150 was maximum.

Phosphorus is an important essential macronutrient required by all plants for growth, development and reproduction. Most agricultural soils in Iran have inadequate P for producing rapeseeds (Brassica napus L.). In these conditions we have two main sources of phosphorus fertilizers for winter rapeseed. Those are biological and chemical sources. In order to study of the influence of phosphor suloblizing bacteria as biological nutrient growth regulator and ammonium phosphate as chemical phosphorus fertilizer on rapeseed yield a field experiments was conducted during September 2007 to October 2008 at the experimental station of Arak Islamic Azad University, Arak, Iran. Phosphor solublizing bacteria at 4 levels (no use, one time use at seeding time, one time use at spring growth and dual use at seeding and also spring growth times) and ammonium phosphate at 3 rates of application (0, 50% and 100% recommended fertilizer according the soil test results used in sowing date) for rapeseed are made the treatments and arrangement as a factorial on randomize complete block design. The results showed grain yield and harvest index had significant difference for chemical fertilizers treatments at 5% levels. Generally, phosphorus contents at vegetative, reproductive and seed maturity stages showed significant increase with biological phosphate treatments.