Plant Productions
Year:2015 | Volume:38 | Issue:1|Papers Count:14

The utilization of organic fertilizer is an effective method in organic culture of medicinal plants. The aim of this study was to determine the effect of organic manure and compost application on growth, development, essential oil content, and microbial load in valerian. The experiment was conducted in randomized complete block design with 3 treatments and 3 replications. The treatments applied organic manure and urban compost compared with control. Morphological traits and essential oil content were recorded and compared in each treatment, and root samples were analyzed for mesophilic aerobic bacteria, total coliforms, yeasts and moulds, and E. coli according to the standard guideline. Results showed that the application of organic manure increased plant leaf area, plant height, and essential oil content significantly (p<0.05); whereas the application of compost could increase plant leaf area, fresh and dry plant weight, fresh and dry root weight, plant height, and essential oil content. Both fertilizers specially compost decreased root length significantly. The effect of treatments on essential oil content was also significant (p<0.05), both organic manure and compost could increase it in comparison to control. Results of microbial load analysis indicated that the effect of treatments on all microbial contamination was not significant; E. coli existence was not proved in any of, treatments and in other microbial contamination all treatments were in the same level. According to these results, the organic manure and compost application could increase essential oil content, and compost increased underground parts of plant weight more, thus increasing the essential oil yield. In microbial quality, organic manure and compost application did not increase product contamination significantly compare to control. So the application of this kind of fertilizers can be advisable in valerian culture.

In recent years, biological approaches such as mycorrhizal symbiosis have been used to alleviate the detrimental effects of drought stress. In a pot experiment the responses of three leek genotypes including Carantan 2 and two Iranian leek genotypes to drought stress and mycorrhizal colonization were compared at Ramin University of Agriculture and Natural Resources in 2010. The experiment was conducted in a completely randomized design consisting of a 3×3×2 factorial combination of three soil moisture levels (the pots were watered when 40, 60 and 80 percent of available water was consumed), two mycorrhizal status (with and without mycorrhiza) and three leek genotypes (Shdegan, Esfahan and Carantan 2). The treatments were replicated four times. The results showed that drought stress significantly decreased all growth parameters including plant height, root and leaf dry weights and total root length. However, mycorrhizal colonization increased all of these parameters at all drought stress levels. Drought stress significantly decreased root length colonized and the percentage of root colonization. Despite this decline in mycorrhizal growth, the response of three leek genotypes increased as drought stress was increased. Among leek genotypes, Shadegan genotype with short root length and low proliferation had the greatest mycorrhizal growth response compared with the two others genotypes. Leaf proline accumulation increased by increasing drought stress. However, this accumulation was lower for mycorrhizal leek genotypes which could be due to the alleviation of the effect of drought stress by mycohhizal fungus. The results of this study indicated that Shdegan genotype with a weak root system had the greatest mycorrhizal dependency.

In order to investigate the effect of seed deterioration (accelerated aging test) on germination and seedling growth indices, an experiment was conducted. The accelerated aging test was carried out at three different temperatures (30, 40 and 50oC) with four duration periods (24, 72, 120 and 144 hr) at 100% relative humidity on three cultivars of safflower (Soffeh, Arak2811 and PI) as a factorial experiment in completely randomized design with three replications in Agricultural Faculty of Yasouj University, in 2010. The results showed that accelerated seed aging or cultivar, temperature and duration period interactions have significant effects on germination percentage (GP) and rate (GR). Generally, by increasing temperature and time, characteristics of the seed germination and seedling growth of safflower such as length and weight of root and shoot and allometric coefficient decreased. According to the results, it seems, among the figures in long storage in hot and humid conditions, Arak-2811 had the most and Soffeh and PI, respectively, the lowest seed quality, including the percentage and rate of germination, root length and dry weight and seed vigor. Among the traits, shoot length, rootlet weight, allometric coefficient and seed vigor index were less affected by genotype and further reacted to deterioration. Consequently, it is advisable that in areas with lack proper facilities for seed storage (without temperature and humidity control) are lacking with more than 40oC for 72h and 100% relative humidity, it is better to use the Arak 2811 variety with the ability to maintain the seed vigor and germination in this condition than Soffeh and PI.

The duration of grain filling period and the rate of this period determines final grain weight in barley. In this study, in order to investigate the effect of final drought stress on rate and duration of grain filling and contribution of stem reserves in main spike yield, a trial was conducted as split-plot design with three replicates (blocks) at Shahid Chamran University in the duration of 2010-2011. The main plot consisted of two irrigation treatments (well-watered and droughted treatment after anthesis) and the split-plot consisted of nine barley cultivars. The results showed that drought had no significant effect on the effective duration of grain filling but reduced the rate of this period by 20%. There was a significant difference between cultivars considering duration of grain filling but they did not show any difference in the rate of grain filling period. Final grain yield ranged between 251 to 536 (g/m2). 25 percent decrease of grain yield by entering drought conditions is almost due and 19 percent decrease in grain weight, because other yield components did not show any significant changes. The yield of main spike showed 24 percent decrease by entering drought conditions. The contribution of stem reserves in the yield of main spike increased by 33% under drought conditions and did not show any significant correlations with maximum weight and length of stem in none of moisture treatments.

In the present research, the effect of paclobutrazol was investigated on mini-tuber production in potato (cultivar Savalan), in the aeroponic system in a factorial experiment based on a randomized complete blocks design with three replications. The first factor was paclobutrazol with 3 levels (0, 50 and 100 mg / l) and the second factor was time of treatment application in 2 levels (30 and 50 days after transplanting plants to the aeroponic system). Results showed that the interaction effect between paclobutrazol concentration and  treatment application time was significant in the number of mini-tubers, mini-tuber fresh and dry weights, plant height and internodes distance traits. Mean comparison for the treatment combination showed that the use of 50 mg/l paclobutrazol in 50 days after transplanting plants to the aeroponic system produced the highest number of mini-tuber (6.9), fresh weight (65 g), dry weight of mini-tuber (11 g), dry weight of root (3.2 g) and stem diameter (9.03 mm). Also, results showed that the use of 50 mg / l of Paclobutrazol during the early stage of mini-tuberization produced the highest number of mini-tuber / plant and mini-tuber yield in m2.

This research compared different characteristics of pollinated and unpollinated fruit of, Shahani, and, Piarom, date palms during fruit development. Physical and chemical characteristics of the pollinated and unpollinated fruits of two cultivars were studied during Kimri, Khalal, Rutab and Tamar stages. The results of variance analysis indicated that, in pollinated fruit, length and diameter increased strongly from Kimri to Khalal stages (17 to 37 mm in, Piarom, and 14 to 19 mm in, Shahani,). The fruit weight reached a maximum at the immature yellow (Khalal) stage during fruit development. Moisture pencentage decreased continually especially in the Tamar stage and rech to 22 and 20 in, Shahani, and, Piarom, respectively. Total soluble solids (TSS) increased progressively during fruit development. The concentration of flavonoid and phenol contents and ash percentage was highest at early stages and then gradually decreased during fruit development to lower concentrations during ripening. Unpollinated fruit did not changed in mineral, ash and fruit weight during fruit ripening. Although TSS increased during fruit development, it was not significant in comparison with pollinated fruit. In general, the fruit of two cultivars, show sigmoid curve. Compored to Unpollinated fruit, pollinated fruit has more phenol and flavonoid but their other characters were lower.

To investigate the combined effects of arbuscular mycorrhizae fungus and salicylic acid on nutrient uptake and distribution of Abareqi Pistachio seedlings under drought stress, an experiment was conducted using a completely randomized design with two mycorrhizae treatments (with or without mycorrhiza), three salicylic acid levels (0, 0.5, 1mM) and four drought stress levels (irrigation with 1, 3, 6 and 10 days intervals). The results indicated that drought strees increased total and shoot K, Fe, Zn, Cu and shoot Mn significantly but it decreased root K and Mn and shoot P. Mycorrhizal application increased total and shoot K, P, Fe, Zn and Cu but reduced root Fe and root and shoot Mn. Salicylic acid application increased total and shoot k but reduced root K, Cu and Mn and total and root Fe and Zn. Mycorrhizal symbiosis had the main role in elements uptake and distribution of K and P while salicylic acid application had a little effect on elements absorption and movement. The maximum amount of shoot K was obtained with mycorrhizae and salicylic acid at 1mM concentration. With respect to the role of K and P in drought resistance, it could be concluded that the use of mycorrhiza alone and in combination with salicylic acid, in part, played a positive role in drought tolerance of Abareqi pistachio seedlings.

In order to study the effects of deficit irrigation and application of biofertilizers on the growing characteristics and water use efficiency (WUE) of Borago officinalis L. a field experiment was conducted in Kermanshah, Iran, in 2011. The experiment was carried out as split plot design with 3 replications. Deficit irrigation was the main factor with four levels, deficit irrigation in vegetative stage, reproductive stage, vegetative + reproductive stages and without deficit irrigation (control), which was applied by interrupting irrigation in the specific stages. Fertilizers incloded three levels, 100% chemical fertilizer, 50% of chemical fertilizer + biofertilizers, 25% chemical fertilizer + biofertilizers. Results indicated that treatments had significant effects on total dry weight, seed, oil percentage, harvest index and water use efficiency. Deficit irrigation on vegetative and reproductive level in comparison with full irrigation decreased 10% and 39% WUE of total dry weight and 13% and 21% WUE for grain. Among the fertilizer treatments, application of 50% of chemical fertilizer + Nitroxin and Biophosphate biofertilizers improved the mentioned criteria in the deficit irrigation condition. And the highest value of seed yield (108/1 kg/ha) was achieved by using 50% of chemical fertilizer + biofertilizers in no deficit irrigation. This treatment (50% + biofertilizers) in no deficit irrigation condition enhanced 26% total dry weight in comparison with utilizing 100% chemical fertilizers.

In order to evaluate the heat tolerance of 11 wheat cultivars, an experiment was conducted during 2010-2011 under two conditions, normal (normal sowing) and heat stress (late sowing), in a randomized complete block design with four replications, in Ahvaz climatic conditions. Traits including chlorophyll content, stomatal conductance and cell membrane thermostability were estimated and also STI, HM, MP, GMP, SSI, TOL, YI and YSI indices were calculated based on grain yield in this research. Stress intensity (SI) equal to 0.59 which is indicative of a relatively severe stress was estimated in this experiment. The results showed a significant difference among genotypes for all traits. The stomatal conductance of heat tolerant cultivars increased significantly under heat stress. This showed the importance of this trait in acclimation of cultivars to heat stress. This trait has the potential to be used for screening the genotypes against heat. The highest quantity for stomatal conductance, 0.59 molm-2s-1 was recorded for Kauz as a tolerant cultivar. Although cultivars showed significant difference for cell membrane thermostability, this trait was not detected as a suitable trait for evaluating the heat tolerance of cultivars. No significant differences were observed for chlorophyll content under normal and heat stress conditions. The average of yield under normal and heat stress was detected as 6381 and 3769kg ha-1 respectively. STI, HM, MP and GMP indices were selected as the best indices based on the correlation with grain yield under normal and heat stress conditions. Results showed that Kauz and Chamran were tolerant cultivars to heat stress and had high performance under normal and heat stress conditions. In contrast, Montana, Niknejad, M6 and Durum-ch-89 cultivars were susceptible to heat stress and had low performance under both normal and heat stress conditions.

Spearmint (Mentha spicata L.) is one of the most important mint family that has numerous applications in food, cosmetical, and pharmaceutical industries due to its valuable medicinal properties. The essential oil content and composition are affected by genotype, climatic, edafic condition and agricultural practices. In this research, the effect of harvest time on plant fresh and leaf dry weights, essential oil content, yield and composition as randomized complete block design with twelve treatments and three replications was studied. Result showed that harvest time had a significant effect on plant fresh and leaf dry weights, essential oil content and yield. The highest plant fresh (2507.3 gr.m-1) and leaf dry (452.2 gr.m-1) weights recorded in July had no significant difference with that of June. Plants also showed the highest amount of essential oil content (2.75%) and yield (6.99 gr.m-1) in September and July, respectively. The main essential oil components were carvone, limonene, careen, a-pinene, myrecene, b-borbonene, cisdihydrocarvone, dihydrocarveol, dihydrocarvyl acetate, Pulgone and trans caryophylene. The highest (57.46%) and lowest (16.83%) amounts of carvone were observed in October and February, respectively. The highest (32.62%) and lowest (2.19%) amounts of limonene were observed in September and March, respectively. The maximum amount of careen (2.87%) was obtained in November. Cis dihydrocarvone, dihidrocarveol and dihydrocarvyl acetate were increased during winter. Overall, in regard to essential oil yield and carvone content, the best time to harvest is from June to September.

In order to investigate the effects of citric acid and salicylic acid as natural compositions on storage life and quality attributes of pear cv .Sardrod fruits, citric acid at 0, 0.25, 0.5 and 1 mmol L- 1 and salicylic acid at 0, 1 and 2 mmol L-1 and different combinations of these treatments, a factorial experiment was conducted in based on completely randomized design. After treatment, fruits were stored at 0±0.5oC for 90 days. The amount of ascorbic acid, total acidity, total phenolics, total antioxidant capacity and fruit firmness was measured in all treatments. The results showed that treated fruits with citric acid (1 mmol L-1) and salicylic acid (2 mmol L-1) had a significant effect on total phenolics, total antioxidant, total acidity and ascorbic acid. Citric acid and salicylic acid prevented fruit softening during storage. The results indicated that the use of citric acid and salicylic acid can be introduced as an effective and successful strategy in postharvest technology of the Pear cv. Sardrud fruit.