Physiologic and molecular responses of indica-japonica subspecies tetraploid rice seed germination to ion beams.

Ionizing radiation can not only reduce the yield of rice but also cause rice toxicity, and consumption of this kind of rice threatens human health. Moreover, the production and application of freon has further caused a hole in the earth's ozone layer, increasing the amount of ionizing radiation from the sun affecting rice. To select and breed new radiation-resistant rice varieties, dry seeds of the indica-japonica subspecies of tetraploid rice subjected to different doses of ionizing radiation were investigated for their responses during germination. The results showed that the relative water absorption, seed vigour and GA3 content sharply decreased in response to three different doses of ionizing radiation, and the regulation of the expression of genes related to α-amylase synthesis and gibberellin metabolism was disrupted. Moreover, the degree of inhibition increased with increasing dose. Notably, under 3.0 × 1017 ions/cm2 radiation, an upregulation of OsGA3ox2 expression resulted in a sharp increase in GA3 content in the indica-japonica tetraploid rice, and upregulated expression of OsAmy3A and OsAmy3D resulted in sharp increase in α-amylase activity, water absorption, and sucrose and fructose contents, which resulted in the seed vigour being greater than that of its parents. The results indicate that additional research on the physiological and molecular features of indica-japonica tetraploid rice seed germination in response to ionizing radiation is needed.

Study of pre-treatment of quinoline in aqueous solution using activated carbon made from low-cost agricultural waste (walnut shells) modified with ammonium persulfate.

Activated carbon made from agricultural waste (walnut shells) was investigated as a suitable adsorbent for effectively removing quinoline from industrial wastewater. The activated carbon was treated with phosphoric acid and oxidized by ammonium persulfate and its ability to adsorb pyridine and quinoline in aqueous solution was investigated. Kinetic parameters for the adsorption process were determined through pseudo-first-order and pseudo-second-order kinetic models and intraparticle diffusion models. Equilibrium experiments and adsorption isotherms were analyzed using Langmuir and Freundlich adsorption isotherms. After reaching equilibrium, the activated carbon adsorbed quinoline in preference to pyridine: the equilibrium adsorptions from individual aqueous solutions (200 µL L-1) of quinoline and pyridine were 166.907 mg g-1 and 72.165 mg g-1, respectively. Thermodynamic studies of quinoline adsorption were conducted at different temperatures and indicated that quinoline adsorption was an endothermic and spontaneous process. The column-adsorption of quinoline and pyridine was consistent with the Thomas model and the Yoon-Nelson model. The removal efficiency of quinoline reached more than 97% for a velocity of 6 mL min-1 at the initial adsorption stage.

Screening of Probiotic Activities of Lactobacilli Strains Isolated from Traditional Tibetan Qula, A Raw Yak Milk Cheese.

In this study, 69 lactobacilli isolated from Tibetan Qula, a raw yak milk cheese, were screened for their potential use as probiotics. The isolates were tested in terms of: Their ability to survive at pH 2.0, pH 3.0, and in the presence of 0.3% bile salts; tolerance of simulated gastric and intestinal juices; antimicrobial activity; sensitivity against 11 specific antibiotics; and their cell surface hydrophobicity. The results show that out of the 69 strains, 29 strains (42%) had survival rates above 90% after 2 h of incubation at pH values of 2.0 or 3.0. Of these 29 strains, 21 strains showed a tolerance for 0.3% bile salt. Incubation of these 21 isolates in simulated gastrointestinal fluid for 3 h revealed survival rates above 90%; the survival rate for 20 of these isolates remained above 90% after 4 h of incubation in simulated intestinal fluid. The viable counts of bacteria after incubation in simulated gastric fluid for 3 h and simulated intestinal fluid for 4 h were both significantly different compared with the counts at 0 h (p<0.001). Further screening performed on the above 20 isolates indicated that all 20 lactobacilli strains exhibited inhibitory activity against Micrococcus luteus ATCC 4698, Bacillus subtilis ATCC 6633, Listeria monocytogenes ATCC 19115, and Salmonella enterica ATCC 43971. Moreover, all of the strains were resistant to vancomycin and streptomycin. Of the 20 strains, three were resistant to all 11 elected antibiotics (ciprofloxacin, erythromycin, tetracycline, penicillin G, ampicillin, streptomycin, polymyxin B, vancomycin, chloramphenicol, rifampicin, and gentamicin) in this study, and five were sensitive to more than half of the antibiotics. Additionally, the cell surface hydrophobicity of seven of the 20 lactobacilli strains was above 70%, including strains Lactobacillus casei 1,133 (92%), Lactobacillus plantarum 1086-1 (82%), Lactobacillus casei 1089 (81%), Lactobacillus casei 1138 (79%), Lactobacillus buchneri 1059 (78%), Lactobacillus plantarum1141 (75%), and Lactobacillus plantarum 1197 (71%). Together, these results suggest that these seven strains are good probiotic candidates, and that tolerance against bile acid, simulated gastric and intestinal juices, antimicrobial activity, antibiotic resistance, and cell surface hydrophobicity could be adopted for preliminary screening of potentially probiotic lactobacilli.

Metabolism of reactive oxygen species in cytoplasmic male sterility of rice by marking upmost pulvinus interval.

Reactive oxygen species (ROS) and malondialdehyde (MDA) in plant cell are thought to be important inducible factors of cell apoptosis if excessively accumulated in cells. To elucidate the metabolic mechanism of MDA production and scavenging in the cytoplasmic male-sterile (CMS) rice, CMS line and maintainer were employed for studying the relationship at different developmental stages by marking upmost pulvinus interval method of experiment. The results showed that the panicles and leaves of the CMS line had a noticeable higher MDA content than those of maintainer line at all five stages that had been investigated (p < 0.05). MDA content in the CMS line in the flag leaves of auricle in the distance 0 mm stage (the meiosis stage) was the highest of the five stages. The increase of MDA contents in sterile panicles and leaves had inducible effects on the enzymic activity of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). However, at the abortion peak stage, MDA was excessively accumulated and antioxidant enzymic activity reduced significantly, resulting in the generation and scavenging of MDA out of balance.

[Observation of the pollen mother cell meiosis of male sterile line in rice by using confocal microscopy].

In the present paper, meiosis of male sterile pollen mother cells and fertility of ripened pollen was observed in male sterile line (Xindao97200A) by using laser scanning confocal microscopy (LSCM), beside, the seed setting rate of selfing and artificial pollination was investigated. Abnormal chromosome behaviors during the meiosis of PMC were found with 15.8%, which included lagging chromosome, dragging chromosomes, three poles of spindles, chromosome bridge, micronuclei and asynchrony of the dyad. Typical, spherical and stained abortive rates were 6.15%, 10.26% and 80.77%, respectively. The pollen abortion might be attributed to abnormal pollen development, which resulted from chromosome pairing abnormally, abnormal division, chromosome breakage and unevenly distributed cytoplasm.

Effect of enhanced UV-B radiation and low-energy N⁺ ion beam radiation on the response of photosynthesis, antioxidant enzymes, and lipid peroxidation in rice (Oryza sativa) seedlings.

To understand the effect of enhanced UV-B radiation and low-energy N(+) ion beam radiation on the response of photosynthesis, antioxidant enzymes, and lipid peroxidation in rice seedlings, Oryza sativa was exposed to three different doses of low-energy N(+) ion beam and enhanced UV-B alone and in combination. Enhanced UV-B caused a marked decline in some photosynthetic parameters (net photosynthetic rate, transpiration rate, and stomatal conductance) and photosynthetic pigments, whereas it induced an increase in hydrogen peroxide (H2O2) accumulation, the rate of superoxide radical production, and the content of malondialdehyde (MDA). Enhanced UV-B also induced an increase in the activity of antioxidant enzymes (superoxide dismutase [SOD], peroxidase (POD), and catalase [CAT]) and some nonenzymatic antioxidants such as proline. Under the combined treatment of enhanced UV-B and low-energy N(+) ion beam at the dose of 3.0 × 10(17) N(+) cm(-2), the activity of antioxidant compounds (SOD, POD, CAT, proline, and glutathione), photosynthetic pigments, and some photosynthetic parameters (net photosynthetic rate, transpiration rate, and stomatal conductance) increased significantly; however, the MDA content, H2O2 accumulation, and rate of superoxide radical production showed a remarkable decrease compared with the enhanced UV-B treatment alone. These results implied that the appropriate dose of low-energy N(+) ion beam treatment may alleviate the damage caused by the enhanced UV-B radiation on rice.

Different responses to N(+) beam implantation between diploid and autotetraploid rice.

The objective of the study is to investigate the biological effects of N(+) beam implantation in different ploidy rice. N(+) beam implantation had increase effect in tillers number, spikelet fertility, grain yield per plant, si-phellem cell size, photosynthetic rate, transpiration rate, flag leaf dry weight, flag leaf culm dry weight, stomatal length, vascular bundle area, and protein and starch content and decrease effect in 1,000-grain weight, stomatal width and chlorophyll, calcium, sodium, and zinc content for all rice lines. N(+) beam implantation had opposite effect on diploid and autotetraploid rice lines in vascular bundle area, stomatal complexes areas, epidermal cell size, era length, area of air spaces, midrib length, papilla number, flag leaf length, flag leaf width, flag leaf area, and cadmium, copper, ferrum, magnesium and phosphorus content. Twenty traits of diploid line and ten traits of autotetraploid line are significantly increased by N(+) beam in this experiment, ranging from 6.8 to 362.7 % in diploid line and 7.9 to 131.7 % in autotetraploid line. Six traits of diploid lines and 15 traits of autotetraploid line are significantly decreased by N(+) beam implantation in this experiment, ranging from 8.9 to 87.4 % in diploid line and 5.6 to 88.5 % in autotetraploid line.

Effects of ion beams pretreatment on damage of UV-B radiation on seedlings of winter wheat (Triticum aestivum L.).

The seeds of winter wheat were pretreated with three different doses of low-energy N(+) beams, and its seedlings were subjected to UV-B irradiation (10.08 kJ m(-2) day(-1)) at three-leaves stage. The growth characteristic of seeds, the oxidative damage to membrane system induced by UV-B radiation, and the alleviating effects of N(+) beams pretreatment to radiation damage were investigated. The results showed that the germination rate and seedling rate, respectively, increased 14.09 ± 1.03 and 13.91 ± 1.21 % compared with control (CK) at the dose of 4.0 × 10(16) ions/cm(2). When seedlings were exposed to UV-B radiation, the pretreatment method under the dose of 4.0 × 10(16) ions/cm(2) made the activity of peroxidase and superoxide dismutase increasing, the content of chlorophyll enhancing, but the content of malondialdehyde reducing significantly compared with that of the single UV-B radiation. Whereas, the activity of catalase irradiated by UV-B improved notably under the pretreatment dose of 8.0 × 10(16) ions/cm(2). In addition, after being irradiated with UV-B, the content of soluble protein and glutathione whose seeds were pretreated by the dose of 6.0 × 10(16) ions/cm(2) were higher than that of the single UV-B radiation. It was suggested that the suitable dose of low-energy ion beams pretreatment to wheat seeds could change its physiological characteristics at seedlings stage to alleviate the damage effects from UV-B radiation.

[Differential expression of the proteins in endosperms of rice with different chromosome sets].

The present paper compared the major storage proteins in starchy endosperm of four autotetraploid rice lines with that of their corresponding diploid rice lines. The content of albumin, globulin, prolamin and glutelin in each sample was determined respectively. The structure and expression pattern of each storage protein was investigated using one-dimensional SDS-PAGE. Our results showed that the protein content of each fraction in endosperm of autotetraploid rice line is mostly higher than that of its corresponding diploid rice line. However, the SDS-PAGE analysis showed that the subunit types of each storage protein of autotetraploid rice line was generally homologous to that of its corresponding diploid rice line, except for one differential band observed on SDS-PAGE gels of total protein fraction and another on the SDS-PAGE gels of albumin and globulin fraction. These results indicated that duplicated genes in autotetraploid rice ac-quired the same expression patterns as that seen in its corresponding diploid rice. It was suggested that the doubling of chromosome sets did not change the protein expression profile but the protein expression level in the starchy endosperm of autotetraploid rice.