نشریه روابط خاک و گیاه
پیاپی 31 (پاییز 1396)

Nitrogen (N) fertilizers are widely used in vegetable production, particularly in leafy vegetables such as sweet basil. Nitrogen fertilizers have high solubility and low efficiency rates and in cropping systems are applied in high amounts that result in different health and environmental problems. Despite their high application, however, the plant’s need of N may not be meet. In this study, growth and production of sweet basil was investigated under application of urea in pellet forms under greenhouse conditions. Treatments were control (without fertilizer application), urea, pellet with low compaction% urea, pellet with low compaction% urea, pellet with high compaction% urea, and pellet with high compaction% urea (w/w) with 4 replications in completely randomized design. Rotted cow-manure was used to make the pellets. Results showed that the highest leaf number per plant, as one of the main yield components in leafy vegetables, the highest plant height and chlorophyll index were in pellet with low compaction% urea treatment. The highest length and width of leaf as well as the highest plant fresh weight were obtained in pellet with low compaction% urea treatment, while the highest dry weight of plant was recorded for pellet with low compaction% urea treatment. The highest leaf N concentration was in urea treatment. Regarding the percentage of essential oil, plants in pellet with low compaction% urea as well as urea treatments showed the highest amount. In general, low compaction% urea treatment showed the best results and could be recommended to be applied in sweet basil production.

Optimization and management of energy in agriculture is one of the main factors to achieve sustainable development. The aim of this research was to evaluate the impact of improving energy use efficiency on CO2 emission reduction in the cucumber-production greenhouses in the central region of Isfahan province. Data were collected on a sample of 81 farmers using two-step clustering and proportionate stratification sampling through face-to-face interview, based on a structured questionnaire, and were analyzed by using data envelopment analysis (DEA) approach. Results showed that average input and output energy consumption was 3232.5 and 166.1 GJ/ha, respectively. Fuel and electricity contained the highest energy shares among input energy sources (74.8 and 16.6 %, respectively). Total CO2 emission was found to be 74941.2 kg /ha, which can be decreased by 45% by following the energy consumption pattern in the efficient greenhouses. In addition, the greatest potential for energy saving is in fuel and electricity consumption patterns. Therefore, adopting sound management and appropriate policies to encourage the farmers in following the efficient greenhouses could lead to a significant reduction in energy consumption and environmental pollution.

This experiment was conducted to determine evapotranspiration, crop coefficient and water use efficiency of cucumber and tomato for a period of six months in the Resarch Greenhouse of Urmia University. Daily evapotranspiration of cucumber, tomato and reference crop was measured using lysimeter method. Based on the results, cucumber evapotranspiration for growth period of 130 days was 272.4 mm and for growth period of 180 days for tomato was 358.6 mm. Based on the reference crop evapotranspiration, the average crop coefficients at the initial, development, mid-season and late season stages of tomato were calculated as 0.2, 0.65, 1.29 and 1.0, respectively, and for cucumber were calculated as 0.19, 0.64, 0.99 and 0.81, respectively. In order to investigate the effects of deficit irrigation on crop yield and water use efficiency, in addition to full irrigation treatment, two levels of deficit irrigation were considered (90 and 80 percent of full irrigation). Maximum yield of tomato and cucumber was obtained under full irrigation as 197.3 and 144.6 ton/ha, respectively. Evapotranspiration water productivity of tomato and cucumber was calculated as 55.04 and 53.1 kg/m3, respectively. Application of deficit irrigation caused a reduction in water use efficiency and crop yield of both crops. Water use efficiency of tomato and cucumber under 80% of full irrigation treatment was 43.7 and 36.2 kg/m3, respectively, which indicated a reduction of about 20 and 31 percent as compared to full irrigation treatment.

Scarcity of conventional water resources and high volume of wastewaters have increased the important role of crop residues to reduce evaporation from soil surface and optimal use of water, especially in greenhouse cultivation. In the present research, the impact of crop residues and fishery’s wastewater on yield, qualitative characteristics and water productivity of cherry tomato was studied. The experiment was carried out with two main treatments (tap water (from a well), w0, and fishery’s wastewater, w1) and four levels of crop residues (0, 5.5, 11 and 16.5 gram crop residue per kg of soil, as M1, M2, M3 and M4, respectively) based on a split-plot design with four replications, in Research Greenhouse of College of Agriculture, Shiraz University. Results showed that fishery’s wastewater increased the yield of cherry tomato more than well water. But application of crop residues in both wastewater and well water treatments increased the yield up to a certain level (11 gram per kg soil), and in 16.5 gram crop residues per kg soil (treatment M4) decreased the yield and evapotranspiration. Fishery’s wastewater did not have any harmful effect on fruit quality. Results also showed that water productivity of wastewater treatment, at all levels of crop residues, was more than well-water treatment. Maximum and minimum fruit yields (0.732 and 0.32 kg per plant) were obtained in W1M3 and W0M4 treatments, respectively. Maximum and minimum amount of net consumptive water use (434 and 348 liters) were obtained in W0M1 and W1M4 treatments, respectively.

Due to production importance and potato minituber sleep, this research was carried out as factorial based on randomized complete blocks design with three replications at the Research Greenhouse of Ferdowsi University of Mashhad, Iran, in 2013. Treatments included foliar application of growth regulators at two physiological growth stages (stolen initiation and tuber initiation) and growth regulator level (control, 100 and 200 mg/L paclobutrazol, 100 and 200 mg/L benzyl aminopurine). Results showed that paclobutrazol treatments significantly reduced number of minitubers per plant, minituber weight, and length and diameter of minituber. Benzyl aminopurine didn’t have significant effect on the mentioned traits. Also, the difference between paclobutrazol concentration levels in term of minituber yield was not significant. Application of 100 and 200 mg/L paclobutrazol at both the stolen and tuber initiation stages increased time of reaching the 5, 10, 50, 90 and 95% of maximum germination of potato minitubers, as compared to control, and most of this effect was at tuber initiation stage. In contrast, application of benzyl aminopurine treatments at tuber initiation stage reduced all germination traits significantly; but there was no difference between different concentrations.

Semperflorens begonia (Begonia semperflorens) is an ornamental house-plant which for its optimal growth and development needs a proper nutrition. Currently, cyanobacteria are sought after by plant growers as a growth bio-stimulant. Spirulina (Spirulina platensis) is an important cyanobacterium which has a vast range of nutritional organic and inorganic substances. This green-blue algae could be a new option of bio-fertilizers for organic cultivation of plants, which merits further investigations in different plants. In this regard, a research with a completely randomized design and five replications was carried out in the greenhouse of the Department of Horticultural Science at Shiraz University, to increase the quality and yield of semperflorens begonia. Spirulina treatments were studied in two forms of soil fertilization and foliar spray (concentrations of 0, 500, 1000, 2000 and 4000 mg/L). Results showed that soil fertilization has greater effect on morphophysiological traits of begonia than foliar spray. Soil fertilization with 4000 mg/L spirulina was the best treatment and compared to the control, significantly increased the vegetative growth, phosphorus, potassium and chlorophyll content of leaves and visual quality of semperflorens begonia. Also, in the abovementioned treatment, the sugar content of leaves, petals’ anthocyanin content and number of flowers were 3, 2 and 2 times higher than control treatment.

The industry of cut flower production is a branch of modern agriculture nowadays. One of the problems in this industry is post-harvest wastes. This research was performed to evaluate the interaction of nano silver and nano calcium particles with four concentrations (0, 10, 20 and 40 mg/L) on the quality and vase life of Alstroemeria cut flowers, cv. ‘Konst Coco’, in a factorial experiment based on a completely randomized design with 3 replications. The recorded traits included morphological and physiological factors as: Flower vase life, relative fresh weight, solution uptake, total dissolved solids, total chlorophyll, ion leakage, ACC oxidase enzyme activity and microbial proliferation. Results revealed that all treatments increased flower vase life of Alstroemeria in comparison to control. The 40 mg/L concentration of calcium and silver nano particles treatment was the most effective treatment in increasing the vase life. This treatment increased the vase life about 14 days as compared to control. Evaluation of microbial proliferation showed that all treatments decreased microbial population in the solution and there were not any microbial proliferation in the treatments with 40 mg/L of silver nano particles until 15th day of the experiment. Other measured traits such as solution uptake and total dissolved solids were also increased by applying calcium and silver nano particles. Reduction of chlorophyll, ACC enzymes activity and ion leakage decreased significantly in all treatments as compared to control. Therefore, the results suggest that 40 mg/L nano silver particles and 40 mg/L nano calcium particles can be used commercially to extend the vase life and keep the quality of Alstroemeria cut flowers.

This research was conducted to investigate the effects of external application of auxin and cytokinin on biochemical characteristics of Stevia (sweet variety), as a factorial experiment with randomized complete blocks design, in Shahed University, Tehran, Iran. Treatments were four levels of NaCl (without salinity (2 mM), 40, 80 and 120 mM) and hormonal factor (0.1 mg/L auxin (IAA) and combined treatment (0.1 mg/L IAA.5 mg/L PBA)), that were conducted as hydroponic culture. Results showed that salinity reduced the amount of biomass. Increased salinity, along with hormones, initially decreased the content of potassium and then showed a steady trend. The highest membrane electrolyte leakage, soluble sugars and protein content of shoots was measured at 120 mM salinity level with 0.1 mg/L IAA and the highest sodium content in shoots was measured in 120 mM NaCl with hormonal treatment of 0.1 mg/L IAA.5 mg/L PBA. Also, hydrogen peroxide reached its highest value in 80 mM NaCl. Proline accumulation increased with increasing salinity. Results indicated that using appropriate concentrations of auxin and cytokinin hormones (especially 0.1 mg/L IAA treatment) in Stevia can be effective in increasing plant resistance to salinity and its application in similar circumstances is recommended for Stevia.

Due to the importance of greenhouse products in Jiroft County, this research was carried out to study the factors affecting adoption of Integrated Pest Management (IPM) operations by greenhouse owners, using Ordered Logit model, in 2014. The studied population consisted of 1650 greenhouse owners and the sample size was determined as 160 farmers, based on Cochran formula. Sampling method was proportional stratified method and required data were collected using a questionnaire. Results showed that about 40% of greenhouse owners do not perform any of IPM operations in their greenhouse, which could eventually lead to environmental unsustainability and jeopardize the food security of the community. Based on the results, the variables including family labor, IPM knowledge level, environmental protection index, participating in extension classes, and type of ownership have had positive impact and greenhouse area and cucumber greenhouses have had negative impact on the adoption level of IPM operations. Therefore, it is suggested that training and extension classes in order to increase the level of IPM knowledge, long-term and low-interest payments for construction of greenhouses to increase greenhouse ownership, and providing inputs for sustainable agriculture in order to increase acceptance of IPM operations, with regard to the government support packages, should be executed.

Grafted rootstocks of fruit vegetables have been widely used in recent years. Due to the availability of local pumpkin germplasms, identification and selection of the landraces resistant to salinity and introducing for production of hybrid rootstocks is necessary. By grafting Spadana cucumber on 3 local landraces ofcucurbits (pumpkin, squash and bottle gourd), 3 imported hybrids of Ferro,19-64 and Shintoza, and Spadana cucumber as self-grafted and ungrafted, totally 8 treatments were compared with respect to NaCl salinity stress (0, 2, 4 and 6 dS/m) and saline agricultural well water (6.6 dS/m). The experiment was performed as factorial with randomized complete blocks design with three replications. Results showed that reduction of plant growth obviously started from 4 dS/m, such that in comparison to no-saline conditions (control), the vegetative growth was decreased by 22%. Salinity of 6 dS/m from NaCl source, interrupted the growth of plants. Saline well-water (6.6 dS/m) was less effective on plant growth than 6 dS/m saline water from NaCl source. Under salinity stress, the length of roots and roots/shoots ratio increased and volume and dry matter of roots decreased. The self-grafted Spadana cucumber had more vigorous growth than ungrafted plants. The local population of pumpkin was more tolerant rootstocks to salinity as compared to the imported landraces. Based on the results of vegetative growth, including plant length, leaf area, volume and dry matter of roots and shoots, the hybrid rootstocks of Ferro, Shinotza and 19-64, and pumpkin, were recognized as tolerant to salinity stress.