JOURNAL OF RESEARCH IN CROP SCIENCES
Year:2013 | Volume:6 | Issue:21|Papers Count:11

In order to study genetic variation for carbohydrate concentration soluble in water and its correlation with cold tolerance (LT50), 119 rain fed barley genotypes were cultivated in 3 replications in Maragheh Agricultural Research Station in a farm condition and their cold tolerant genotypes (measured by LT50) and its relationships to the amount and type of water-soluble carbohydrate were determined. The LT50 measurement results showed that there was genetic diversity among the studied genotypes and genotype tolerance varied from 9 - to 16 - degree Celsius. Soluble sugars ranged from 15 to 54 mg carbohydrate for genotypes of dry leaves in fluctuation. Furthermore, cold tolerance showed a positive correlation with water soluble carbohydrates (r=0.23*) (r=0.13). In summary, the results of this study showed that barley genotypes of winter growth together with higher water soluble carbohydrate generally had more cold tolerance and could endure the Hardening stage in the dry land farming in mountainous cold areas. So selection for cold tolerance can be determined by measuring the amount of carbohydrates in leaves and growth habit in barley breeding programs.

In order to evaluate the drought stress effects and seed pretreatment with cycocel as a plant growth regulator on forage yield and some vegetative characteristics of maize (Zea maize L.) cultivars, a field experiment was conducted on split split plot design by a randomized complete block design with three replications in Khoy Agricultural Research Center. In This experiment, irrigation as the main factor in four levels (complete irrigation as the control and eliminating one stage of irrigation at the beginning of stalking, tasseling and dough stages), cultivars KSC704 and KSC666 as the sub factors and application of pretreatment form of chlormequat chloride in three levels (non consumption, consumption with 0.4 and 0.8 g/lit dose) as the sub-sub factor were considered. Eliminating of irrigation in stalking stage reduced significantly the stem diameter, plant height, dry weight of the leaf and ear and totally dry weight of forage. Also, eliminating of irrigation in tasseling stage reduced the plant height, dry weight of ear and forage significantly. Between the two experimental cultivars, KSC704 (81.438 t/ha) had better performance than KSC666 (74/170 t/ha) in forage yield. The application of the cycocel in producing forage crops not only is illogical but also has little effects on the experiment results. The results of this experiment showed that the most sensitive growth stages of maize against drought stress were stalking and tasseling stages. Then by choosing the proper irrigation timing in water shortage conditions, the damages can be prevented.

Understanding of the phenological and morphological basis of seed yield has an important role in rapeseed prolific yield. To prove this, a field experiment was conducted as a randomized complete blocks design with four replications using 8 rapeseed cultivars (Okapi, Amika, Orient, Zarfam, Sarigol, Talayeh, Hayola308 and Hayola401) in research farm of Islamic Azad University, Pars Abad Moghan Branch in 2009-2010. The aim of this study was to detect the relationship between phenological phases with seed yield of rapeseed. Results showed that difference between cultivars was significant (P<0.01) and it concluded that cultivars could be divided into three groups based on grain yield: high, medium and low yielding cultivars. High yielding cultivar (Hyola401) with respect to phenological development pattern was earlier in flowering, pod development and physiological maturity stages and had also longer flowering period. Comparison of morphological traits between high and low yielding cultivars showed that traits such as biological yield, pod number per main raceme, pod number per plant, seed number per pod, length of main raceme and branch number per plant had the most effect on increasing of yield in the high yielding cultivars. So, the highest and lowest yield were recorded in Hyola401 (5.75 t/ha) and Orient (3.07 t/ha) respectively. Therefore, those traits are promised standards to choose for the prolific rapeseed cultivar.

Increasing the yield of crops, especially corn, as the third most important cereal in the world and our country in terms of economy and consumption is particularly important. Organic fertilizers, as a natural input that produces humus and other organic residuals with no harmful side effects on environment, can be effective in enhancing the yield of silage corn, especially in the different environmental conditions. In order to investigate the effect of nitrogen from both chemical and organic sources a study was conducted in a randomized complete block design with three replications at the Agricultural Research Station of Khoy in 2012. Experimental treatments were comprised of different types of fertilizers including urea in top-dress and spraying applications, micro-elements Librel BMX, liquid fertilizer developed for corn, and three types of organic fertilizers; KN25 HumTak, KN60 HumTak and KN30 HumTak with 2.5, 6 and 30% of organic matter, respectively, which were sprayed on the leaves. All treatments were applied at the recommended concentrations either in soil (urea) or on leaves three times in 10-day intervals. Five characteristics of the plants including plant height, stem diameter, and dry weight of whole plant, leaves and stem were measured. Significant differences were observed among the mean of all characters in all treatments with control at P≤0.05. The greatest effect was calculated in mixture of Humtak 6% and top-dress urea with 21.21ton/ha of whole plant dry matter. The lowest effect was observed in the control treatment with 16.52 ton /ha of dry matter. Treatment Humtak 6% + top-dress urea produced the tallest corn plants with height of 296.8 cm. Regarding the results attained it was concluded that using a combination of organic and chemical fertilizers yielded higher production of corn in comparison with using only organic or chemical fertilizers.

The effects of different concentrations of plant-derived smoke extract (0, 1:500, 1:100, 1:10, 1:5 and 1) and aerosol smoke on germination and seed vigor a medicinal Specie Sanguisorba minor were investigated in two separate experiments. The first experiment was conducted as a random complete block design (RCB) with three replications and second experiment was arranged as a completely randomized design (CRD) with four replications. Results of the first experiment showed that smoke extract dilutions of 0.002, 0.01, 0.1 and 0.2 improved germination speed, germination percentage and vigor index while the concentration of 1 decreased germination speed and vigor index. The concentrations of 0.2 and 0.1 were the best solutions improving the majority of the studied traits. In the second experiment, all the germination and seedling growth parameters except root length and root/shoot length ratio were improved following the exposure of seeds to aerosol smoke compared to control. Consequently, the application of plant-derived smoke either as smoke extract or aerosol smoke positively affected the germination and seedling growth of the salad burnet.

In order to study the effect of growth stimulants and Nano-fertilizers used as foliar application on nuts sunflower seed yield and yield of its ingredients, a field experiment was conducted in 2013 in suburbs of Khoy as factorial in completely randomized block design with 3 replications. The first factor was in 3 levels which included a1, without the usage of growth inducers a2, Fylloton foliar application containing 19 essential Amino Acids. a3, Ferti Buy foliar application which contained (sea weed, Nitrogen, phosphate and potassium). Second factor was Nano-fertilizers at 3 levels including b1, with no fertilizer, b2, foliar application of kalate sepehr1 containing Nano-fertilizer like (Mn, Cu and Mg) and b3, Nano-fertilizer foliar application of kalate sepehr3 which included nutrients like: (B and Zn). Results of analysis of variance showed that among head diameter, seed yield and biological yield, there was a considerable statistical difference at least in 5% probability level for one of the levels in factors and their efficiency on each other. Between treated combinations of efficiency on each one Ferti Buy growth inducer with Nano-fertilizer kalate sepehr 1 had the most seed yield 3067 kg/h. so that seed yield at this treatment showed 68% increase in comparison with control treatment.

To investigate the relationships between grain yield and some characteristics affecting the yield performance, an experiment was conducted in the 11 lines of winter wheat (Triticum aestivum L.) with 4 cultivars (Oroum, Zareh, Mihan and Zarrin) in completely randomized block design with three replications in research station of Miyandoab in 2010-2011. Analysis of variance showed that there were significant differences among all traits except of peduncle weight. Most lines studied, such as lines 5, 10, 11, 13, 14 and 15 with the mean grain weight had an average of 34/68 mg, lines 5 and 15 with an average of 4/698 pcs had more number of spikes per square meter, the greatest height with an average of 92.85 cm allotted to lines 4 and 9, the highest average spike weight, were allotted to lines 3, 9, 14, 4 and 6, the highest percentage HI, with an average of 06.42%, were allotted to lines 3, 11 and 14. Golden figure of the average yield of 8078 kg per hectare gave the highest grain yield. The correlation results showed that grain yield with plant height (r= 0.56*) and spike weight (r= 0.56*) had positive and significant correlation. The results of regression analysis 90.2 % of the variation in grain yield through plant height, number of spikelet per spike, grain weight per spike, spike weight, spike length and harvest index were justified. Based on the path analysis traits such as plant height (1.41), weight of spikes (1.95) and HI (0.93) as the most effective and positive direct effect on grain yield traits, and spike grain weight (-1.47), the largest negative effect on spike length (-0.57), had the least negative impact. Thus it can be concluded that traits under study can be used in breeding programs to select promising and high yielding wheat genotypes.

In order to attain suitable forage clipping and estimating nitrogen fertilizer for the most economical proficiency with the highest qualification of forage in triticale, an experiment was carried out at Saatlo station in 2010- 2011. A factorial experiment was done based on randomized complete block design with 4 replications. The first factor was three levels of clipping stages including non-clipping, clipping at tillering and booting stages. Different levels of nitrogen fertilizer including 0, 40, 80, 120 and 160kg/ha were arranged at second factor. Results showed that non-clipping and clipping at booting stage with 610.5 and 203.1g.m2 had the most and lowest grain yield respectively. The highest economical proficiency 3743.06$/ha resulted with using 80kg/ha nitrogen fertilizer and non-clipping. Considering both forage and grain yield, it is necessary that clipping be done at tillering stage with using of 120kg/ha nitrogen fertilizer. At regression of economical proficiency traits of grain yield, stalk and total dry matter remained at the final model. Economical proficiency had significant positive correlation with number of spike per m2 (0.87**), grain yield (0.64**), total dry matter (0.65**), plant height (0.52**) and 1000-kernal weight (0.54**).

In order to investigate the effect of micronutrients foliar application of B, Zn, Fe, Mn, Mo on qualitative and quantitative characteristics of six 2970, 261, A1-O-type, 7233-P.29, 191, ET5 sugar beet genotypes two experiments were carried out under field conditions in 2010 season. These experiments were conducted based on randomized complete blocks design with three replications in Uremia and Karaj agricultural research stations. Foliar application was done at 8-12 leaf stage. Combined analysis of variance showed that for traits of root yield, sugar yield and white sugar yield, sugar content, accumulations of sodium, potassium and nitrogen and purity percentage, there were significant differences between treatments, interaction genotype×location (P≤0.05). Tetraploied ET5 sugar beet genotype with 83.6t/ha roots yield and 11.4t/ha white sugar yield was more than other diploied sugar beet genotypes. With increasing accumulations of sodium, potassium and nitrogen in root, white sugar yield decreased. Amount of sugar content under Uremia conditions (18.5%) was more than Karaj (17.5%). Micronutrients foliar application increased purity percentage of sugar beet.

To study the effect of anti-transpiration application on forage corn in water deficit condition, an experiment was conducted during the 2013 in Khoy Agricultural Research Center; therefore, a Split Plot on the base of Randomized Complete Block Design was used in 3 replications. Main factors were irrigations in 2 levels including: irrigation after 75 mm evaporation (control) and irrigation after 150 mm evaporation from pan A. Sub factors were anti-transpiration in 7 levels including: Ascorbic acid application amount of 100, 200 and 300 ppm, Salicylic acid, application of 100, 200 and 300 ppm and control (non-application). Drought stress had significant effect on plant height, ear length, leaf fresh weight and forage fresh weight. Irrigation after 75 mm evaporation with the average of 76219.0 kg/ha had the most fresh forage and irrigation after 150 mm evaporation with average of 57490.6 kg/ha had the least fresh forage. Anti-transpiration materials had significant effect on leaf fresh weight and forage fresh weight. Salicylic acid foliar applications treatments of 100 and 300 ppm with average of 74463.7 and 60613.0 kg/ha were the maximum and minimum of fresh forage yield, respectively. Interaction of these factors had significant effect on the corn ear length.