Nutrient use efficiency and nutrient uptake promoting of rice by potassium solubilizing bacteria (KSB)

The current study was carried out in both pot and field conditions to investigate the effects of three KSB strains of Pantoea agglomerans, Rahnella aquatilis and Pseudomonas orientalis on nitrogen (N), phosphorous (P) and potassium (K) uptake, nutrient use efficiency parameters and nutrients remobilization in rice (Oryza sativa L. cv. Pajohesh). The experiments included 15 treatments of KSB inoculations, commercial K biofertilizer and K chemical fertilizer. The results showed that the inoculums of all three KSB strains increased the K, N and P uptake by grain and straw, especially when applied in combination with ½ K chemical fertilizer (47.5 Kg/ha) as compared to the control treatment. The highest value of available K in the soil obtained from NPK chemical fertilizer equal to 140.1 and 134.6 mg K per kg of soil in the pot and field experiments, respectively, which were significantly higher than KSB inoculations treatments. Bacterial inoculums coupled with ½ K chemical fertilizer also enhanced the nutrient use efficiency (including agronomic efficiency (AE), apparent recovery efficiency (ARE), physiological efficiency (PE), agro-physiological efficiency (APE), internal utilization efficiency (UE), partial factor productivity (PFP), partial nutrient balance (PNB)) and nutrient remobilization. The results indicated that the bioinoculation with these KSB strains isolated from soil paddy could be considered as an effective way to increase potassium, nitrogen and phosphorus uptake by rice plant and enhance their use efficiency and remobilization to grains in the flooding irrigation conditions

The Growth Analysis of Corn (Zea mays L. cv. SC 604) With Different Fertilizers Application

To investigate the responses growth indices of corn (Zea mays L. cv. SC 604) to using plant growth promoting rhizobacteria (PGPR) and phosphate solubilizing microorganisms (PSM) and rhizobacteria, a field experiment was conducted during 2008. The study was arranged in split plot experiment based on randomized complete block design with three replications. Three levels of manures, consisted of 20 Mg.ha-1 farmyard manure, 15 Mg.ha-1 green manure and check or without any manures assigned to main plots and eight levels of fertilizer combinations (consisted of 1-NPK or recommended fertilizer application; 2-NPK+PSM+PGPR; 3-NP50%K+PSM +PGPR; 4-N50%PK+PSM+ PGPR; 5-N50%P50%K+PSM+ PGPR; 6-PK+PGPR; 7-NK+PSM and 8-PSM+ PGPR) to sub plots. Results showed that the maximum dry matter (13/2 g.m-2), leaf area index (3/8) and crop growth rate (34/5 g.m-2.day-1) were, produced by using both farmyard manure and application of NPK plus biofertilizers. Application of green manure and biofertilizer significantly increased dry matter by 11% compared to control. Meanwhile, farmyard manure and green manure application markedly increased the leaf area index by 17 and 10%, respectively. NPK treatment in farmyard manure plots and inoculation of PGPR and PSM significantly increased crop growth rate in corn plants compared to green manure and control plots. However, inoculation of biofertilizer and reducing P application by 50% did not significant influence growth indices such as total dry matter accumulation, leaf area index, and crop growth rate significantly. In conclusion, it seems that biofertilizers could be recommended as an effective option to reduce phosphate chemical fertilizers, improve the growth indices of corn plants, which ultimately result in grain yield increase

The Effect of Different Levels of Nitrogen Fertilizer on Yield and Agronomic Characteristics of Basil (Ocimum basilicum L.) Intercropped with Cowpea (Vigna unguiculata L.) and Affected by Weed Competition

In order to study the intercropping of basil (Ocimum basiilicum L.) and cowpea (Vigna unguiculata  L.) under different levels of nitrogen supply and weed competition conditions, a field experiment was carried out in split-split plot arrangement based on a randomized complete block design with three replications during 2010 and 2011 at Sari Agricultural Science and Natural Resources University. Experimental factors included weed treatment (weed free and weed infested), three levels of nitrogen fertilizer (0, 50 and 100 kg ha-1), and different planting ratios (monoculture of cowpea and basil, additive planting ratio 25, 50 and 75% basil). In weed control conditions, the maximum yield of cowpea (684 kg ha-1) and dry matter yield of basil (420 kg ha-1) were belonged to 20, 50 percent of basil ratio and 50 and100 kg ha-1 nitrogen fertilizers, respectively. The highest amount of essence yield in weed free and weed infested were 69.24 and 70.40 percent as compared to the basil monocropping which belonged to 50 and 25 percent of additive basil intercropping with 100 kg ha-1 nitrogen application, respectively. Also, the dry weight of shoot and oil yield in monoculture treatments were significantly higher than intercropping. The leaf percent and the ratio of leaf and flower to stem in basil plant were significantly lower in monocropping than intercropping. In weed infested conditions, the highest percentage of stem (62.18) and basil dry yield (160 kg ha-1) were recorded in 25 percent of basil ratio and 100 kg ha-1 of nitrogen application. Also, the highest system productivity index (1517) and land equivalent ratio (LER=1.31) were belonged to 50 percent of basil ratio and 50 kg ha-1of nitrogen fertilizer in weed free conditions which shows that intercropping is more efficient than monocropping

A taxonomy and review of the multiple criteria decision-making literature in chemical engineering

10.1504/IJMCDM.2011.043556International Journal of Multicriteria Decision Making14407-46

Effects of plant growth promoting microorganisms inoculums on mineral nutrition, growth and productivity of rice (Oryza sativa L.)

Two field experiments were carried out separately to evaluate the ability of three plant growth promoting microorganisms (PGPM, Pantoea ananatis, Enterobacter sp. and Piriformospora indica) as bio-fertilizer on rice (Oryza sativa L.) productivity under different levels of potassium sulfate fertilizer (PSF). The results clearly showed that the PGPM significantly enhance the dry weight of rice plant tissues as compared with the control. Uptake of phosphorus and potassium in rice plant tissues and also nutrient use efficiency (NUE) remarkably increased especially when the co-inoculation with P. ananatis and P. indica in experiment I and the combined (seed + seedling root) inoculation method in experiment II were used. Grain yield (GY) increased linearly with the addition of PSF up to 110kg ha−1 for the co-inoculation treatment (23% lower than the control), then remained constant at its maximum (5348kg ha−1, 32% higher than the control) up to 180kg ha−1 in experiment I. Similarly, the maximum value of GY (5330kg ha−1, 20% more than the control) was obtained at 100kg ha−1 PSF in experiment II. Consequently, both co-inoculation and combined inoculation methods could be selected as the best ways for improving NUE and plant growth of rice in sustainable production systems

Leaf photosynthetic characteristics and photosystem ii photochemistry of rice (Oryza sativa L.) under potassium-solubilizing bacteria inoculation

The current research was performed to investigate the effects of three potassium-solubilizing bacteria (KSB) strains (Pantoea agglomerans, Rahnella aquatilis, and Pseudomonas orientalis) on leaf photosynthetic characteristics in rice (Oryza sativa L. cv. Pajohesh). A pot and a field experiment were conducted in a paddy field. The results indicated that the KSB inoculums significantly enhanced chlorophyll (Chl) a, Chl a+b, SPAD value, and stomatal conductance as compared to the control in both experiments, especially when applied along with half the recommended dose of the potassium chemical fertilizer. KSB inoculations, alone or combined with K fertilizer, significantly increased the value of photochemical quenching, photosynthetic electron transport rate, and the effective quantum efficiency as compared to the control. In conclusion, these native KSB strains could be used as inoculants to reduce consumption of K chemical fertilizer and improve the efficiency of photosynthesis for rice production under the flooding irrigation conditions

Understanding farm-level differences in environmental impact and eco-efficiency: The case of rice production in Iran

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