نشریه بوم شناسی گیاهان زراعی
سال دهم شماره 2 (پیاپی 35، تابستان 1393)

The study aim was identifying of effective factors on canola farmers’ adoption to sustainable agriculture. The research tools were the questionnaire, which panel of experts had confirmed its validity, and its reliability had been reported from 0.75 to 0.85. The target population of the study consisted of all canola farmers in Golestan province (N=7543), according to Cochran’ formula, a number of 365 people were selected using statistical sampling in a stratified randomization method. Finally, 296 questionnaires were gathered and analyzed (n=296). The knowledge and adoption of canola farmers majority about sustainable agriculture were at moderate and acceptable levels, respectively. The main practices of sustainable agriculture were observing proper time for cultivating, proper time for using chemical fertilizers, and amount of seeds, respectively. Furthermore, the main pushing factors of developing sustainable agriculture were management factor, attitude toward sustainable agriculture, and the amount of using information channels, respectively. In multiple linear regression analysis,social participation, extension-education participation, knowledge about and attitude toward sustainable agriculture”explained37.30 %of the variation of the adoption of sustainable agriculture bycanola farmers.In this regard, it is recommended that training sessions with providing the necessary incentives to farmers,besides increasing knowledge and improving their attitudes, the methods that contribute to the sustainability of crop production should be emphasized.

Recently, there is an increasing attention to plant pathogen’s biocontrol considering hazards and environmental threats of chemical pesticides. Therefore, using plant materials as safe and natural antimicrobes is going to be investigated in recent years. The current study’s projective was evaluation of plant materials obtained from purple coneflower effecting on Xanthomonas arboricola pv. juglandis bacterial walnut blight agent. Aqueous, methanol, ethanol, acetone and HCl extracts of coneflower root, stem, leaf and flower were extracted by rotary set and flower essential oils using clevenger apparatus. The antimicrobial activity of coneflower extracts and essential oil was evaluated in laboratory with disc diffusion and minimal inhibitory and bactericide concentration methods. The bacterium was more sensitive to flower essential oil than extracts. Ethanol acted successfully in antimicrobial material release from plant organs. Also, aqueous extract and also HCl and acetone extracts had very limited antibacterial activities on studied bacterium. All plant extracts and essential oils were inhibitive on bacterium. Leaf extract were more inhibitive than bactericide. Regarding the results plant materials obtained from coneflower could be a remarkable potential against walnut blight bacterium and might be considered as a promising biocontrol agent in the future.

To study the effect of sowing dates on yield and yield components of sunflower cultivars as a second crop, an experiment was conducted in Research Field of Education Center of Jihade-Agriculture of Hamedan. The experiment was carried out in factorial based on randomized complete block design with three replications. The first factor was sowing date including 20th May, 25th June and 10th July and the second factor was sunflower cultivar vic. Sirna, Euroflor and Armaviruski. Acoording to the results, there were significant differences in seed and biological yield, head diameter, thousand seed weight in P <0.01 level. Also, there were significant differences in harvest index, number of seeds in head, plant height in P <0.05 lrvel. Conventional sowing date (20th May) had the highest seed yield (495.45 g m-2) and both 25th June and 10th July had the minimum values. Conventional sowing date and 25th June were placed in similar groups based on harvest index, biological yield, number of seed per head and thousand seeds weight traits, but were more than 10th July. About plant height, the highest value related to 25th June. There were significant differences among cultivars about head diameter, 1000-seeds weight (P <0.05) and plant height (P <0.01). The highest head diameter and plant height related to Euroflor and Armaviruski cultivars, respectively. Armaviruski cultivar had the highest plant height in compared with the others. Delay sowing date of 25th June is suggested in this climate of region and it is possible to cultivate all three cultivars in this region after cereal harvesting (especially Barley).

Sirjan plain is one of main and potential areas of pistachio cultivation in Kerman province, Iran. A east to west transect perpendicular to Sirjan plain development was selected, and 15 profiles were described and sampled in the present physiographics under pistachio cultivation. Physical and chemical property of soil samples were determined and classified up to family level. The Ocric horizon was separated in surface layer and Salic, Gyosic and Cambic horizons was in lower layers. During transect, profiles from east to west classified of Entisols and Aridisols and at least development shown in East and greatest change was observed in center and west of transect. Physiography of the gravelly alluvial and colluvial fans (East and South- East) has been less affected by soil formation processes than in flood plains and low lands (West). The main parameters affecting pistachio production are soil texture and gravel in East of transect (profiles 1 to 4) and salinity, sodium adsorption ratio, gypsum, high groundwater levels and physical properties in the Center and West of transect (4 to 12). For efficient land use under cultivation exact study and monitoring information, correct salinity and alkalinity, management of gypsic soils and improvement of soil fertility and organic matter is recommended.

Root knot causing by nematodes is a major disease of tobacco in all tobacco-producing countries in subtropical and tropical zones. Resistant cultivars implementation is the preferable economic management method. Nematicides are expensive and may pollute the environment. Therefore, this study evaluated reaction of 100 flue-cured tobacco genotypes to Meloidogyne incognita based on completely randomized design with three replications in greenhouse at 25 ± 3oC of Tirtash Research and Education Center in 2010-2011 years. Each tobacco seedling was inoculated with 2000 eggs and second stage juveniles in 1.5 kg pot soil. After 60-70 days they have evaluated according to gall index, reproduction factors, number of egg masses and average of eggs per egg mass. Results of variance analysis showed that there were significant differences among cultivars. Genotypes of Coker 176, Mac Nair 944, S 392-3 S, TL33 and Bel 61-10 had the lowest gall index and reproduction factors. Eighteen susceptible and resistance genotypes were selected based on results of 2010 year and based on completely randomized design with five replications. The experiment was conducted in Tirtash Research and Education Center in 2011 year. Results of variance analysis showed that there were significant differences among the cultivars. Genotypes of Bel 61-10 with the lowest of gall index, reproduction factors, number of egg masses and average of eggs per egg mass, respectively 2, 1.1, 38.2 and 357 and Coker 176 by 1.6, 1.18, 38 and 354 as resistant genotypes were introduced. Genotype of Bel 61-10 as resistant parents in breeding work will be used in the future. Cultivar of Coker 176 for cultivation in the affected tobacco growing areas to root knot nematode is recommending.

This study during the year of 2011 and 2012 in horticultural research station and seed and plant improvement Institute, Karaj as factorial on the base completely randomized design was done. Factors include almond seedlings tested in 6 levels (supernova, Perlis, D 124, Marcona, Rabie, and k1-16) and osmotic stress of polyethylene glycol in 5 levels (0, 2-, 4-, -6 and 8-bar). The results showed that with drought stress on plants, plant height, number of leaves, the amount of chlorophyll a, chlorophyll b and total chlorophyll, the amount of glucose and fructose content, relative humidity content decreased and the amount of proline and the rate of ion leakage increased, but increase or reduce these traits in the cultivars with each other had significant differences. The results of investigation growth traits showed that Peerless and k66 cultivars had the most sensitivity to the drought so that the number of these plants leaves and their height under osmotic stress -2 bar are reduced in comparative with plant control significantly. The most resistance to drought was shown in D-124 and Marcona cultivars so that osmotic stress could endure up to -6 bars and only in osmotic stress -8 bars, the number of leaves and their height was significantly reduced compared with control plants. The results from physiological and biochemical characteristics were very similar with the results of the measurements on morphological traits. D-124 and Marcona cultivars had the highest level of production proline and the lowest ion leakage. They were diagnosed as the most resistance to drought stress, while cultivar k16 had the most sensitive to drought stress.

To study the effect of seed priming by salicylic acid and nano-iron chelate on germination and initial growth of lentil under salinity stress, a factorial experiment was conducted based on completely randomized design with three replications. Treatments was contained priming with salicylic acid and nano-iron chelate each with three levels (1000, 2000 and 3000 mg.L-1), hydropriming with distilled water and control (non-priming) and four salinity levels (control, 1000, 2000 and 3000 mg.L-1). The results showed that seed priming by salicylic acid and nano-iron chelate had significant effect on germination percentage and rate, emergence percentage and rate, mean of germination and emergence time mean, plumule length, fresh and dry weight under salinity stress. The sodium chloride salt with 3000 mg.L-1 rate caused significant decrement in seedling germination and initial growth characteristics, comparing to control. In the present study, salicylic acid showed positive effect on germination and growth characteristics of lentil seedling under salinity stress with and without nano-iron chelate, so that germination and initial growth characteristics of lentil seedling were increased by application of salicylic acid in sole and under salinity stress, comparing to control. Therefore, applying seed priming by salicylic acid with 3000 mg.L-1 to improve germination and establishment of seedling with or without salinity stress condition is going to be recommended.

To study the effects of ecological weeds management by some of companion crops on agronomic traits of corn (single cross 504), an experiment was carried out in 2011 in Research Farm of faculty of agriculture at University Tabriz. The experiment was carried out in a factorial arrangement with the base of randomized complete block design in three repetitions. The treatments of this experiment included type of medical and cover plant in 4 levels (Clover, hairy vetch, basil and dill) as first factorial and time of cultivating cover and medical plant in tow levels (synchronic cultivation with corn and cultivation 15 days after corn cultivation) as second factorial. The results showed that the among companion crops, the cultivation of clover with corn had highest amount in all traits compared to other treatments because clover could closer rapid canopy that due to better control of weeds in the early stages of growth and decreased competition of inter specific. Also, synchronic cultivation companion crops with corn relation to cultivation 15 days after corn cultivation in all traits had highest amount, and lowest mean of density and weed biomass was observed in synchronic cultivation corn with clover. Hence with the attention to importance of life environmental issues and the above cost due consumption of herbicide for weeds control has been recommend if possible for weeds control in farms has been used on the one of companion crops or medicinal crops instead of herbicide toxins.