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1.
To find out more about the biochemical aspects of seed-softness trait in pomegranate (Punica granatum L.), some of the phenylpropanoid pathway enzymes as well as their products were evaluated in the various soft- and hard-seeded genotypes during fruit development. Results showed that peroxidase (POD) activity decreased in all studied genotypes during fruit growth, while increasing at the last stages only in the hard-seeded genotypes. Although laccase (LAC) activity did not show high differences during fruit ripening and in different genotypes, but its general trend was increasing. Phenylalanine ammonia-lyase (PAL) activity decreased during the fruit development and approximately diminished for the hard-seeded genotypes. All genotypes had lignin components in their seeds and amount of lignin increased during the growth season. Total phenolic decreased drastically and antioxidant capacity increased gradually showing an opposite trend and probable competitive effect for the same substrate during fruit development. Considerable differences that were observed in the POD activity at the last sampling stage, and higher activity that was observed in POD than LAC, may indicate that POD is more important for polymerization of lignin in the pomegranate seed and this enzyme might have some role in the development of seed softness trait in pomegranate. Also, this is the first report about lignin detection in the seeds of soft-seeded pomegranate genotypes, and represents a different mechanism (such as monolignol conformation in the final polymer) from lignin content for development of the soft-seeded pomegranate genotype.  相似文献   
2.
This study evaluated the effects of gypsum on the release rate of potassium (K) and iron (Fe) from phlogopite to alfalfa under greenhouse conditions. The medium was a mixture of quartz sand as filling material, K- and Fe-bearing micaceous mineral (phlogopite) and different levels of gypsum (0%, 2%, 5%, 12% and 25%). During the 6-month cultivation period, the pots were irrigated and/or fed with distilled water and four different nutrient solutions. The results showed statistically significant effects of different levels of gypsum on dry weight and K and Fe concentration of shoots and roots. It seems that an increase in calcium (Ca) concentration, due to the addition of gypsum, changes the equilibrium of K and Fe in the root zone and plant tissues. The results of this study show that the rate of K and Fe release from micaceous minerals is extremely reduced in the presence of gypsum.  相似文献   
3.
The present study was conducted to evaluate the effects of a skip‐a‐day feed removal early in life on physiological parameters and ascites occurrence in broilers reared at a high altitude (2100 m above sealevel) under regular or cold temperatures. Three hundred 1‐day‐old male broilers were divided into two equal groups. One group was placed in an enclosure with standard thermal management. The other group treated for the induction of ascites was raised under cold temperature conditions. In each enclosure, birds were randomly assigned to one of two treatment groups (three replicate floor pens of 25 chicks per treatment group): (i) a control was fed a standard starter and grower diet according to the National Research Council; or (ii) a skip‐a‐day feed removal, which was similar to the control except for 24 h fasting intervals at 9, 11 and 13 days of age. Results indicate that live bodyweight following the feed removal at up to 42 days of age was significantly different between the control and skip‐a‐day restricted birds (P < 0.01). Skip‐a‐day feed removal resulted in decreased weight gain (P = 0.005) but did not influence feed conversion ratio. The heterophil : lymphocyte ratio was numerically higher for the cold environment and increased when birds were exposed to fasting, but these differences were not significant. Hematocrit was significantly higher (P = 0.0001) in broilers raised in cold conditions whereas it was not influenced by feed restriction. Circulatory thyroid hormone concentrations were not influenced by the feed restriction program under both environments. Birds subjected to cold had significantly lower (P = 0.0023) carcass yield compared to those reared at normal temperature. Breast yield and abdominal fat deposition were not influenced by cold or feed restriction. A reduction in mortality from ascites was noted in broilers who experienced early skip‐a‐day feed removal under both environmental conditions.  相似文献   
4.
The aim of this paper is to investigate vertical wicking in polyacrylonitrile (PAN) electrospinning nanofiber yarn using image analysis. Colored liquid rising phenomenon into the yarn and the distance of liquid rise were determined as a function of time. The kinetics of capillary rise follows the Lucas-Washburn equation. The results show that capillary rise rate coefficient is being reduced with increasing yarn twist, due to the reduction of continuity and size of capillaries. Increasing heat treatment stretch from 0 % (draw ratio=1) to 50 % (draw ratio=1.5) increases the capillary rise rate coefficient, due to the more homogeneity of capillary spaces in the yarn structure and increasing heat treatment stretch from 50 to 100 % (draw ratio=2) reduces capillary rise rate coefficient, because of the low capillary length. The present study indicates that an appropriate choice in production parameters of nanofiber yarn is all important in obtaining the desired properties of capillary rise.  相似文献   
5.
6.
Abstract

Many methods have been proposed to recommend phosphorus fertilizer, but none of them can quantitatively determine the plant phosphorus required. In this method, which is called “Integrated Plant and Soil System” (IPSS), the required phosphorus of the plant is calculated quantitatively, based off of the correlation between soil phosphorus, soil properties, and plant organs phosphorus. For this purpose, 39 Orange orchards were chosen in Jahrom (Iran). In each orchard during two consecutive years, samples were taken from the plant organs and soil of the root zone and phosphorus was measured. A multivariable regression was established between variables that had a significant correlation with soil phosphorus. The result of IPSS was two regression models between soil and fruit phosphorus. A regression model for high yield orchards (Y2?=?–121.3799?+?0.1256308X2), and the other for orchards that have a phosphorus deficiency (Y1?=?–96.4673?+?0.120549X1). According to these regressions, calculating the amount of phosphorus required for orange trees is possible.  相似文献   
7.
Fruit traits and molecular markers (RAPD) were used to survey genetic similarities and inheritance pattern of offspring, derived from self- and open pollination of pomegranate cv. Malase-Tourshe-Saveh (MTS) as well as progenies derived from cross between ‘MTS’ and ‘Narm-Daneh’ (ND) a soft-seed cultivar in the present study. Clustering based on fruit traits, divided the accessions firstly into two major groups, sweets and sour or sweet–sours. Members of sub-clusters were different in fruit characters, and seed softness also was affecting the grouping of individuals. Offspring of ‘MTS’ × ’ND’ showed somehow seed softness with varying degrees compared to other individuals. In RAPD analysis, by using 26 polymorphic primers, 325 fragments were produced from 39 individuals, among which 70 reproducible, polymorphic bands were scored for data analysis. NTsys and Bootstrap software were used for RAPD data analysis and respective dendrogram depicted by Jaccard's similarity coefficients using UPGMA method. The similarity coefficients were ranging from 0.2 to 0.94 and the lowest was obtained between pollen parent (ND cv.) and a genotype from open pollination of MTS cultivar. The highest similarity coefficient (0.94) was observed between two offspring both from self-pollination of MTS cultivar. In corresponding dendrogram, pollen parent was separated from other genotypes and laid individually in a sub-cluster, while the mother plant clustered with its progenies. In addition, some marker–trait associations were observed, especially for seed softness.  相似文献   
8.
This experiment was conducted to investigate the impact of foliar spraying salicylic acid (SA) and methyl Jasmonate (MJ) on the physiology responses of strawberry (Fragaria × ananassa cv. Camarosa’) grown under salinity stress. According to results, SA and MJ significantly reduced the injuries caused by salt stress, possibly through promoting K+ accumulation as well as decreasing the electrolyte leakage and Na+ contents in the leaves. The best protective effects resulted from 0.75 mM SA and 0.25 mM MJ treatments. These results indicate that SA and MJ can effectively improve the defense system and antioxidant capacity of strawberry in the salt affected environments.  相似文献   
9.
Macroelements in leaves and fruits, sugar of fruits, and yield of ‘Khatooni’ melon were compared with melons grafted onto rootstocks cvs. ‘Ace’, ‘Shintozwa’, and ‘ShintoHongto’, and trained into three methods: T1) no pinching and fruit thinning; T2) pinched to produce two lateral branches; and T3) pinched to two branches and all flowers and lateral branches from lower nodes thinned. Concentrations of nitrogen (N), phosphorus (P), and potassium (K) increased in leaves onto ‘Shintozwa’, whereas opposite trends observed for magnesium (Mg) and calcium (Ca). N, P, and K in leaves were significantly higher by 21.5%, 17.2%, and 18.6%, respectively in grafted. N, P and K in fruits onto ‘Ace’ and ‘Shintozwa’ were higher, with exception of Ca and Mg in non-grafted. ‘Ace’ and ‘Shintozwa’ resulted in significant increase in Khatooni yield. T3 showed the highest yield. Soluble solids concentration (SSC) was higher in non-grafted fruits. T2 produced fruits with the highest SSC.  相似文献   
10.
The aim of present study was to identify accumulator plants that are effective for phytoremediation. We chose a mine of Iron and Copper named Hame Kasi that located western north of Hamedan city as a polluted area. In this region concentration of heavy metals is several times more than non-polluted area. Seventeen plant species and 6 soil samples were collected from this region for determination of heavy metals content. Atomic Absorption Spectrophotometer (AAS) was used for analysis of heavy metals in soil and plant samples, then tested plant species were grouped on the basis of their accumulation capability of heavy metals. The results of this research showed that there are some hyper accumulator plants in this area that can concentrate heavy metals in their different parts thus they can be used for remediation of polluted area.  相似文献   
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