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201.
Low phosphorus use efficiency (PUE) is one of the major reasons of poor wheat production worldwide. Among the various approaches used to enhance PUE, polymer coated fertilizers are relatively a new concept. Keeping this in view, a field study was conducted to evaluate polymer coated di-ammonium phosphate (DAP) to enhance growth, yield and PUE of wheat. Commercial DAP and polymer coated DAP (50%, 75% and 100% of recommended dose) were tested in wheat. Results revealed that application of 50% polymer coated DAP produced the same results or higher than 100% commercial DAP. However, the maximum increase in growth (plant height, root length, number of tillers m?2, inter-nodal distance), yield (number of grains per spike, 1000 grain weight, grain yield and biological yield) and phosphorus acquisition by wheat was observed with 100% polymer coated DAP. Moreover, 100% polymer coated DAP increased phosphorus recovery and agronomic efficiency compared to other treatments.  相似文献   
202.
Cellulolytic bacteria have a bio-activating role in the composting process. A study was carried out to isolate and identify cellulolytic bacteria from various sources. The isolates were cultured in the carboxymethyl cellulose (CMC) agar medium and incubated at 30°C for 3–7 days. Based on morphological characteristics of the isolates, maximum diameter of a clear zone around the colony and maximum cellulolytic activity, eight isolate were selected for further studies regarding composting experiments.

Molecular tests based on PCR amplification and sequencing of 16S rRNA gene of isolates showed the closest phylogenetic similarity with the species of Stenotrophomonas rhizophila DSM14405 (99.8%), Brevibacterium halotolerans DSM8802 (99.6%), Achromobacter marplatensis B2 (99.8%), Bacillus methylotrophicus CBMB205 (100%), Pseudomonas azotoformans IAM 1603 (99.7%), Bacillus sonorensis NBRC 101234 (99.8%), Bacillus subtilis KCTC 13429 (100%) and Ochrobactrum thiophenivorans DSM 7216 (99.3%). The study of the isolates impact on the composting of palm wastes in a randomized complete block design with 11 treatments in 3 replications showed that strain IB (B. methylotrophicus) caused a significant decrease in C:N ratio (58%). The increasing of microbial respiration compared with control after 30 days incubation at 37°C showed that the B. methylotrophicus strain IB with cellulolytic characteristics can be applied to hydrolysis of cellulosic biomass in the composting processes.  相似文献   

203.
Iran is amongst the countries in the world widely known for cultivation of Prunus spp. (or stone fruits). It is both a centre of origin and diversity of the stone fruits. Numerous wild species as well as many cultivars and landraces of these fruit crops are important genetic resources today in Iran and can be used for improvement and breeding of scion and rootstock cultivars which are resistant to many biotic and abiotic stresses through modern genomics and genetic technologies. This paper discusses the distribution, ethno-botany, diversity and utilization of wild and domesticated genetic resources of stone fruits including almond (Prunus dulcis (Miller) D. A. Webb.), peach and nectarine (P. persica Batsch), European and Japanese plum (P. × domestica L., and P. salicina L., respectively), sweet and sour cherry (P. avium L., and P. cerasus L., respectively), and apricot (P. armeniaca L.), all of which are members of the Rosaceae family. The goal of this paper is to highlight the importance of Iran as a main contributor to the diversity of Prunus genetic resources in the world, as well as, present major achievements regarding identification, collection, evaluation, conservation and utilization of this valuable genetic resource in Iran.  相似文献   
204.
The photo-Fenton oxidation treatment combined with a coagulation/flocculation process was investigated for removal of chemical oxygen demand (COD) from a refractory petroleum refinery wastewater. Scrap iron shavings were used as the catalyst source. A response surface methodology (RSM) with a cubic IV optimal design was employed for optimizing the treatment process. Kinetic studies showed that the proposed process could be described by a two-stage, second-order reaction model. Experiments showed that precipitation of iron ions can be utilized as a post-oxidation coagulation stage to improve the overall treatment efficiency. More than 96.9% of the COD removal was achieved under optimal conditions, with a post-oxidation coagulation stage accounting for about 30% of the removal, thus confirming the collaborative role of oxidation and coagulation in the overall treatment. A low-velocity gradient of 8.0 s?1 for a short mixing time of 10 min resulted in optimum post-oxidation coagulation. Comparison of photo-Fenton oxidation to a standard Fenton reaction in the same wastewater showed more rapid COD removal for photo-Fenton, with an initial second-order rate constant of 4.0 × 10?4 L mg?1 min?1 compared to the Fenton reaction’s overall second-order rate constant of 7.0 × 10?5 L mg?1 min?1.  相似文献   
205.
206.
The present study aimed to determine the effect of nephthyl acetic acid (NAA) on the physiological mechanism of drought tolerance in selected maize (Zea mays L.) varieties under induced drought stress at the vegetative stage. Maize seeds were sown in plastic pots (14 cm lower inside diameter, 18.5 cm upper inner diameter, 15.6 cm height, and 0.5 cm thickness) filled with 3 kg of air-dried soil and sand (3:1) in triplicate in the greenhouse of the Botany Department, Bacha Khan University, Charsadda in 2014. Results showed that the activities of antioxidant enzymes and proline accumulation were associated with the dry mass production and consequently with the drought tolerance of the maize varieties. It has been concluded that the inhibitory effects of water stress were ameliorated by exogenous application of NAA and were found to be significant for antioxidant enzymes at the vegetative stage in both varieties.  相似文献   
207.
208.
In recent decades, ambient gaseous pollution has increased due to anthropogenic activities worldwide. The studies to evaluate the adverse effects of ambient pollutants on commonly grown food crops are still limited, especially in Asian countries like Pakistan. The present study was conducted to measure the ambient pollutants in different sites of Faisalabad and their impact on growth and yield of wheat, mung bean and peas. Plants were grown in pots and placed at three sites named as control (Wire house of Government College University, Faisalabad), low pollution (LP) (Farm Area of Ayub Agricultural Research Institute) and high pollution (HP) (GT Chowk, Faisalabad) sites. Results showed that ambient ozone (O3) concentration was highest at HP site followed by LP site and was below AOT40 in control site. Ambient pollutants caused foliar injury in crops and decreased plant height, leaf area, biomass and grain yield. Pollutants caused a reduction in photosynthetic pigments, stomatal conductance and net photosynthetic rate and grain protein contents in all three crops. In conclusion, the ambient O3 level was highest at HP site, this current O3 level and other pollutants decreased the growth and yield of important food crops.  相似文献   
209.
The present work was carried out to study the potential of bacteria isolated from the seeds of rice plant for the biocontrol of five rice pathogenic fungi. Eleven endophytic bacteria isolated from rice seeds were evaluated for their antagonistic potential. Of five pathogens studied, only the growth of Magnaporthe grisea was inhibited by one bacterial isolate in an in vitro dual culture assay. Based on 16S rDNA sequence analysis, and biochemical and morphological characteristics, this strain was closely related to Stenotrophomonas maltophilia. We named this new isolate to be S. maltophilia SEN1 (seed endophyte). This isolate was further tested for the production of volatile and diffusible antibiotics against M. grisea, for plant growth-promoting (PGP) traits and colonization of some rice cultivars. In addition, S. maltophilia SEN1 was tested for its ability to promote plant growth and reduce the incidence of rice blast disease under greenhouse conditions. When applied to the soil, this isolate increased seedling growth and suppressed blast disease in plants of three studied cultivars. This study also showed this isolate could colonize the root interior of other rice cultivars. This study indicates that the S. maltophilia isolate studied has an excellent potential to be used as biocontrol agents of M. grisea or biofertilizer under in vitro and in vivo conditions.  相似文献   
210.
The effect of a combination of (-)-epigallocatechin-3-gallate (EGCG) with fish oil on intestinal tumorigenesis in Apc (Min/+) mice fed a high-fat diet was investigated in the present study. The combined treatment of EGCG and fish oil for 9 weeks reduced the tumor number by 53% as compared to controls while neither agent alone had a significant effect. Apoptosis was significantly increased in all treatment groups. beta-Catenin nuclear positivity in adenomas from the combination group was lower than control mice, implicating the modulation of Wnt signaling by the combination. Fish oil and the combination significantly reduced prostaglandin E 2 (PGE 2) levels in small intestinal tumors as compared to controls, suggesting modulation of aberrant arachidonic acid metabolism by fish oil. Akt phosphorylation in adenomas was significantly reduced in all treatment groups, which may have contributed to the observed increase in apoptosis. The results indicate that a combination of low doses of EGCG and fish oil can inhibit tumor multiplicity in Apc (Min/+) mice.  相似文献   
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