Soil science
H. Auobi; J. Nabati; Ahmad Nezami; M. Kafi
Abstract
Introduction: The excessive use of chemical fertilizers devastates soil fertility and causes different types of environmental pollution. Therefore, using adequate eco-friendly fertilizers in agriculture enhances productivity but has no adverse effect on nature. Recently, there has been reported that ...
Read More
Introduction: The excessive use of chemical fertilizers devastates soil fertility and causes different types of environmental pollution. Therefore, using adequate eco-friendly fertilizers in agriculture enhances productivity but has no adverse effect on nature. Recently, there has been reported that beneficial soil microbes produce some volatile organic compounds, which are beneficial to plants. The amendment of these microbes with locally available organic materials and nanoparticles is currently used to formulate biofertilizers for increasing plant productivity. These bacteria are naturally present in soils, but their population decreases for a long time because of long-term environmental stress, improper use of chemical agents, and the absence of a suitable host plant. Adding these bacteria to the soil, before or during the growing season, increases the growth and production of agricultural products. Since available water is the main growth limiting factor in chickpea cultivation, it is useful to improve nutrition, especially using plant growth-promoting rhizobacteria, for accelerating the growth and development of plants at the end of the season.
Materials and Methods: In order to evaluate the effect of bio-nutrition and seed priming on growth and yield of chickpea genotypes (MCC463, MCC741, ILC8617, ILC72, FLIP02-51C) an experiment was carried in split plots based on Randomized Complete Block Design with three replications in 2019. Experimental factors included nutritional treatments as the main plots and chickpea genotypes as the subplots. Nutritional treatments were 1- seed priming with the use of free-living nitrogen fixing bacteria, phosphorus solubilizing bacteria and potassium solubilizing bacteria (P + BF), 2- free-living nitrogen fixing bacteria, phosphorus solubilizing bacteria and potassium solubilizing bacteria before sowing (BF), 3- seed priming with the application of free-living nitrogen fixing bacteria, phosphorus solubilizing bacteria and potassium solubilizing bacteria with foliar application of amino acid, potassium and silicon during growth stages (P + BF + F), 4- application of free-living nitrogen fixing bacteria, phosphorus solubilizing bacteria and potassium solubilizing bacteria before planting with foliar application of amino acid, potassium and silicon during growth stages (BF + F), and 5- control (without biological and chemical fertilizers). Free-living nitrogen fixing bacteria, phosphorus solubilizing bacteria and potassium solubilizing bacteria were sprayed five liters per hectare on the soil surface before planting with 107 CFU per ml and mixed with soil. Foliar application with amino acid (1:1000) was done in two stages (before flowering and 50% flowering stage), and foliar application with potassium (1:1000) and silicon (1.5:1000) was carried out in the 50% flowering stage.
Results and Discussion: Results showed that the highest concentration of chlorophyll a was obtained for BF and MCC463 with an increase of 3.1 times greater than control. The highest concentration of chlorophyll b was obtained for BF + F and FLIP02-51. The highest green area index was recorded for MCC741 in P + BF. The highest number of pods per plant in MCC463 and FLIP02-51 was observed in BF + F, with 88 and 30% more than the control, respectively. The highest biomass produced was obtained for ILC8617 and BF + F, by 24% higher than the control. ILC72 and MCC463 showed the highest grain yield in P + BF + F treatment, which increased grain yield by 35% and 4% (320 and 50 kg/ha), respectively, with respect to control. MCC741under BF treatment showed a doubled (810 kg/ha) grain yield relative to control. The highest grain yield for P + BF was found in ILC8617 and increased by 28% (340 kg/ha) as compared to control. In this genotype, grain yield in BF + F was also significantly greater than that in the control by 22%, (270 kg/ha). FLIP02-51 grain yield in BF increased by 12% (170 kg/ha) as compared with the control.
Conclusion: In terms of seed yield, ILC72 and MCC463 were more responsive to P + BF + F and ILC8617 and FLIP02-51 in the BF and ILC8617 in P + BF with respect to other treatments. It seems that despite the positive effect of biofertilizer, genetic characteristics of genotypes are influential in plant growth and yield; therefore, it is necessary to select the appropriate genotype for each region so as to make the most utilization of the nutrients and achieve high yield.
Abdolhossein ziaeyan; Ali Reza Farahbakhash; Hossein Besharati; lLadan Joukar
Abstract
Introduction: The most abundant of agricultural soils in Iran, are calcareous. In calcareous soils, phosphorus fertilizers use efficiency is low. The usage of soil microorganisms is one of the effective ways to increment the uptake of phosphorus in calcareous soils. This microorganisms using various ...
Read More
Introduction: The most abundant of agricultural soils in Iran, are calcareous. In calcareous soils, phosphorus fertilizers use efficiency is low. The usage of soil microorganisms is one of the effective ways to increment the uptake of phosphorus in calcareous soils. This microorganisms using various mechanisms, including the production of plant hormones or the production of organic and inorganic acids to dissolve the insoluble phosphorous compounds. Mycorrhizal symbiosis is also one of the most recognized and important symbiosis relationship found in the world. In a mycorrhizal symbiosis,plants can be able to absorb more nutrients and water from soil and fungus plays a protective role as a growth enhancer and make the plants more tolerable to biotic (pathogens) and abiotic (drought, cold and salinity) stresses .This research conducted to study phosphate solubilizing bacteria and mycorrhiza roles on sorghum growth and phosphorus availability to this plant.
Materials and methods: To achieve the desired goals, a pot experiment was conducted as a factorial in completely randomized design with sixteen treatments in three replications. The treatments were combination of four P levels of zero, 25, 50, and 75 mg kg-1 P2O5 from triple super phosphate source, the two treatments of inoculation and without inoculation of phosphate solubilizing bacteria and the two treatments of inoculation and no inoculation of mycorrizal fungus. Required fertilizers based on initial soil test results were supplied. Accordingly, the same amount of nitrogen, 80 mg kg-1 (30 mg kg-1 before planting and 50 mg kg-1 after planting twice) as urea source, 10 mg Zn kg-1 and 5 mg kg-1 Cu per kg soil as the forms of Zinc sulphate (ZnSO4.7H2O) and copper sulphate (CuSO4.H2O) were added to each soil sample. Required Phosphorus also was calculated based on treatments and added to potting soil. Each pot size was 5 kg. every sample was thoroughly mixed and then were placed in pots. At the same time the seeds were inoculated. In harvesting time, some parameters such as plant height and diameter, wet and dry foliage yield, and phosphorous uptake were measured and analyzed statistically. After harvesting time also soils phosphorous content were measured and analyzed.
Results Discussion: The results indicated that by utilizing the phosphate solubilizing bacteria, stem diameter, dry matter yield, phosphorous uptake, and soils phosphorous content after harvesting significantly increased. These findings indicated that the use of phosphate solubilizing bacteria affected plant growth. Such results have been previously reported. Ramezanian (31) reported that application of PGPR will be increase wheat stem height and diameter. Li et al (18) and Larsen et al (16) reported that soil microorganisms, including growth promoting bacteria through a variety of mechanisms such as ACC deaminase production or an increase in available phosphorus can stimulate plant growth and increase height and diameter of the stem. Glick et al (13) showed that plant growth promoting bacteria through the production of plants hormones increases plant height and stem diameter, and ultimately improve plants yield. Increases yield of plants through the use of phosphate solubilizing bacteria previously has been reported by other studies. Mycorrizal inoculation also had a significant effect (P
A. Fallah Nosrat Abad; Sh. shariati
Abstract
The high cost of fertilizers in farming systems, soil pollution and degradation of soil are factors that caused to full use of available renewable nutrient sources of plant (organic and biological) with optimal application of fertilizers in order to maintain fertility, structure, biological activity, ...
Read More
The high cost of fertilizers in farming systems, soil pollution and degradation of soil are factors that caused to full use of available renewable nutrient sources of plant (organic and biological) with optimal application of fertilizers in order to maintain fertility, structure, biological activity, exchange capacity and water-holding capacity of the water in soil. Therefore, in recent years, according to investigators biofertilizers and organic farming as an alternative to chemical fertilizers has been drawn. Through this study, we examined the effects of triple superphosphate, organic matters and phosphate solubilizing microorganisms on quantitative and qualitative yield of wheat and nutrient uptake. The experiment was carried out in the factorial based on randomized complete block design. The factors were: 1-phosphate solubilizing bacteria in three levels including control, Pseudomonas Putida and Bacillus Coagulans bacteria, 2- triple superphosphate in five levels of 0, 25%, 50%, 75% and 100% and 3-organic matter in 2 levels of 0 and 15 ton/ha in the soil with high phosphorous accessibility (13 mg/kg soil) but lower than sufficient limit for plant 15 mg/kg soil). The results showed that the highest amount of yield has been recorded in Pseudomonas Putida bacteria treatment with organic matter and 25% phosphate fertilizer. As a result, at the conditions of this experiment phosphate solubilizing bacteria and organic matter significantly had higher yield than control and their combination with phosphate fertilizer had significant effect on reducing phosphate fertilizer use.
