04 December 2015, Volume 29 Issue 12
-
Select all|
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2253-2258. https://doi.org/10.11869/j.issn.100-8551.2015.12.2253In order to excavate more genes related to rice anther development, one rice male sterility mutant tda (tapetum degradation anther) was isolated from a japonica rice Songxiangzaogeng through 60Co-γ rays irradiation. The characteristic of tda cytological and genetic was investigated.The result showed that,there was no obvious phenotype difference appeared during tda vegetative development stage, the tda anther was small and white although the inflorescence and floral development was normal during the reproductive growth stage. The paraffin sections analysis exhibited that, until meiosis stage, there was no clear difference was observed between tda and wild type anthers. At the microspore stage, tda tapetum displayed aberrant predegradation and the microspore was irregular. Subsequently, the tda microspore was gradually shrinked and could not develop into mature pollen. The genetic analysis found that, tda phenotype was controlled by a single recessive nuclear gene. These results laid a basis for TDA gene cloning,functional analysis and the molecular mechanism research of rice anther development.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2259-2267. https://doi.org/10.11869/j.issn.100-8551.2015.12.2259For establishment of marker-assisted selection (MAS) system for breeding rice varieties with high resistant starch content, Jiangtangdao 1 was used as a high RS donor parent and crossed with three high yield rice varieties Miyang23, Xiushui123 and Hudao55 respectively. Grain chalkiness, amylose content (AC) and functional marker (CAPS/SpeI) we used as assistant markers for high RS content selection in the early generation. The results showed that grain chalkiness characteristics were positively correlated with RS content. Most of low RS content plants could be eliminated according to chalkiness degree and high chalky grain percentage. The high RS homozygous plants could be precisely identified by further utilization of a functional marker CAPS/SpeI of sbe3-rs. Through continuous self-fertilization and marker-assisted selection (MAS), three rice varieties RS23, RS123 and RS55 with high yield, good quality and high RS content were bred. In conclusion, it is feasible to efficiently eliminate most of low RS-content plants in early generations by choosing seeds with high chalkiness characteristics, moreover, the combination of utilization a functional marker could significantly improve the selection efficiency and accuracy. In this study, an efficient MAS system for breeding of high RS content rice varieties was established which paved the way for providing new theoretical basis and materials for RS breeding in the future.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2268-2275. https://doi.org/10.11869/j.issn.100-8551.2015.12.2268Polyphenol oxidase (polyphenol oxidase, PPO) activity is closely related to the wheat flour whiteness. In order to improve quality of local wheat varieties using Russian germplasm, Three STS markers linked with polyphenol oxidase (PPO) genes located on chromosome 2AL and 2DL were used to screening 250 wheat varieties derived from Russia and 125 wheat varieties from Heilongjiang Province. The results showed that PPO18, a co-dominant STS marker located on chromosome 2AL, could amplify a 685-bp and a 876-bp fragment related to PPO-2Aa (high PPO) and PPO-2Ab(low PPO) respectively. For the wheat varieties derived from Russia, PPO-2Aa and PPO-2Ab were detected in 182 and 68 varieties, with the frequency of 72.8% and 27.2% respectively. For that of Heilongjiang Province, PPO-2Aa and PPO-2Ab were detected in 76 and 45 varieties with the frequency of 60.8% and 36% respectively, and no bands were detected in 4 varieties with a frequency of 3.2%. Two complementary dominant markers located on chromosome 2DL, PPO16 and PPO29, could amplify a 713-bp and a 490-bp fragment in the genotypes with PPO-2Da (low PPO) and PPO-2Db (high PPO), respectively. For the wheat varieties from Russia, PPO-2Da and PPO-2Db were detected in 109 and 141 varieties, with the frequency of 43.6% and 56.4%, respectively. For that of Heilongjiang Province, PPO-2Da/PPO-2Db were found in 60 and 65 varieties, with the frequency of 48% and 52%, respectively. There were five different genotypes combinations between the two PPO markers, and the distribution of genotypes combination was different in varieties of Russia and Heilongjiang. For double low activity genotypes combinations PPO-2Ab/PPO-2Da, the distribution in varieties of Heilongjiang Province is 5.6% more than that of Russia. These results provide molecular genetic information for the utilization of Russian germplasm resources to improve wheat breeding in Heilongjiang Province.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2276-2286. https://doi.org/10.11869/j.issn.100-8551.2015.12.2276In this study, to learn the structure and function of the sucrose transporter gene (SUT1) of sweet sorghum, we first obtained the full-length cDNA of SUT1 by using homology-based cloning together with RACE technology. The cDNA sequence was then analyzed by using a variety of bioinformatics databases and software. The full-length cDNA of SUT1 contained 2472 base pairs, with a coding region of 1560 base pairs. This sequence encoded a protein of 519 amino acids in length with a molecular weight of 55kDa and a theoretical isoelectric point (pI) of 8.86. SUT1 was found to encode a hydrophobic membrane protein for which there was no signal peptide and corresponding cleavage site in its sequence. The SUT1 protein's topology featured 12 distinct transmembrane helices, 12 conserved domains, six serine phosphorylation sites, four threonine phosphorylation sites, two tyrosine phosphorylation sites, and a low complexity region. At the subcellular level, the SUT1 protein was mainly localized to the chloroplast thylakoid membrane, plasma membrane, Golgi body, and the membrane of endoplasmic reticulum. The secondary structure of SUT1 was mainly composed of alpha helix, consisting of 43.35% helix,34.68% random coil, 19.08% extended strand, and 2.89% beta turn. The SUT1 protein seemed to mainly play a role in the processes of transport and binding. The analysis of SUT1 gene expression indicated that it was expressed at varying levels in different tissues. The highest expression levels were found in the leaves, followed by the sheath, stem, and root, respectively, with the lowest expression in the tassel. By cloning the SUT1 gene and preliminarily predicting its structure, nature and functions, we have acquired valuable information which can be used to study the biological function of the SUT1 gene with respect to the relationship between source and sink in sweet sorghum.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2287-2293. https://doi.org/10.11869/j.issn.100-8551.2015.12.2287In order to clarify the change rules and inheritance of Vc content in pepper fruit, fruit Vc content in different pepper genotypes at different maturity levels, and adopted the joint segregation analysis method of major gene plus polygene for Vc content genetic analysis in red ripe fruits were studied. Results showed that the Vc content in the fruit of hot pepper genotypes was significantly higher than in sweet pepper genotypes. And in most varieties, significantly higher Vc content was found in ripe fruit than in mature green fruit, then decreased in the subsequent stages. The Vc content of red fruit was controlled by a pair of additive-dominance major genes and additive-dominance-epistasis polygene (D-0 model), with d value of 18.4276 and h value of-13.3018, indicating the obvious and positive main additive effect and the high-level dominant-negative major genes. The heritability rates for major genes and polygene in F2 generation were 25.97% and 17.13%, respectively. That the acquired genetic variation accounting for 43.1% of phenotypic variation, and environmental variation accounting for the remanent 56.9%, indicating that environmental variation was dominant. This study provided a scientific basis for pepper high quality breeding from the aspect of fruit Vc content.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2294-2299. https://doi.org/10.11869/j.issn.100-8551.2015.12.2294To confirm the role of miR1917 in plant response to microgravity, the ethylene level in the culture environment, the phenotypes responded to ethylene of tomatoes, as well as the expression quantity of miRNA1917 and its target gene LeCTR4 was detected . In the experiment, ethylene related phenotypes including hypocotyl bending geotropically and developing spirals were observed. The quantity of malonaldehyde (MDA) and superoxide anion in the environment increases along the time. These reactions are clearly affected by the microgravity treatment. The difference of ethylene level in the culture environments is significant only in the initial period (day 10 to day 20). After 20 days, there is almost no difference. The relative expression quantity of miRNA1917 increases along the time, while the relative expression quantity of its target gene keeps decreasing. Therefore, the phenotypes of hypocotyl bending geotropically and developing spirals are related to the ethylene level in the initial microgravity treatment period. In the later period (after 20 days), the accumulation of MDA and superoxide anion are related to the expression quantity of miRNA1917. This is because the increase of the expression quantity of miRNA1917 leads to the decrease of its target gene, which negatively controls the phenotype response to ethylene. Hence, the plant is more sensitive to the ethylene level in the environment. miRNA1917 play a role in plant microgravity response through reducing the amount of its target gene to increasing the sensitivity to ethylene,. The study laid a foundation for the establishment of plant microgravity response process mediated by miRNA.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2300-2306. https://doi.org/10.11869/j.issn.100-8551.2015.12.2300In order to investigate the reproductive features of Cymbidium faberi and clarify reason for the low seed germination, the reproductive features mainly on the aspects of ovule development and developmental events distribution were investigated. Results indicated that the embryo sac development of C. faberi followed a rarely bisporic pattern and the development of ovules showed hugely asynchronized. Megasporogenesis mainly occurred during 40 to 45 days after pollination (DAP). Approximately 40 DAP, about 22.33% archesporial cells differentiated into megasporocytes. After the first meiotic division, the megasporocyte polarized into two equal dyad cells. The chalazal one continued to enlarge via vacuolation and then was formed into the functional megaspore. During 45 to 55 DAP, megasporogenesis finished while embryo sac began to development. The megaspore first developed into uni-nucleate embryo sac directly. After the second meiosis, the two-nucleate embryo sac was formed showing two nuclei migrating to the opposite end of the sac. As a result of the mitosis of both formed nuclei, the four-nucleate embryo sac was formed and, the additional divisions resulted in an eight-nucleate embryo sac. Uni-(27.33%), two-(30.67%) and four-nucleate embryo sac (9.33%) were all observed at 45 DAP. About 32.33% of ovules, the highest probability, had developed into mature embryo sacs at 55 DAP. At 60 DAP, most of the ovules had finished megagametogenesis. The asynchronous development of ovules is probably responsible for the different embryo development in C. faberi which might results in the low ratio of seed germination in vitro . The study may provide important guidance for further researches on embryo development and determining the time for harvesting seed.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2307-2312. https://doi.org/10.11869/j.issn.100-8551.2015.12.2307In order to eliminate the interference effects of aldehyde and soluble saccharide in determination of MDA of final products of lipoxygenase isoenzyme, HPLC method was applied to study the differences in MDA contents in rice materials with different lipoxygenase isoenzyme activities under high temperature and high humidity, ambient temperature and humidity conditions. The results showed that the effect of LOX-3、LOX-1,2 to MDA reached its maximum in 4d and 2d separately, and by comparing the highest values and their production times, the contribution speed of LOX-1,2 to MDA was approximately 2 times higher than LOX-3.So it can be concluded that the process of LOX-1, 2 to attack membrane lipid and start membrane lipid peroxidation is higher than that of LOX-3. The study is to provide theoretical basis for the study of rice deterioration.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2313-2319. https://doi.org/10.11869/j.issn.100-8551.2015.12.2313In order to determine the microstructer of Salmonella biofilm and its transfer to food-processing surfaces. As compared to a standard growth media (TSB), a meat thawing-loss broth (MTLB) was used as a growth culture in biofilm formation. Based on evaluation of the microstructer of biofilm in the two growth culture, the ‘sandwich-transfer’ method was used to test the transfer rates of biofilm from stainless steel surfaces to other 5 food processing surfaces. The results showed that the cells number in biofilm grown in TSB were greater than that in biofilm grown in MTLB. The confocal laser scanning microscopy (CLSM) results showed that Salmonella grown in MTLB showed ‘cloud-shaped’ morphology in the mature biofilm, whereas when grown in TSB appeared ‘reticular-shaped’. However, there was no significant difference in microstructer of biofilm when grown in the two different media, confirmed by scanning electron microscopy (SEM). The transfer rates (RTs) of biofilm were significantly influenced by the types of processing surfaces, with stainless steel and glass surface showing higher RTs in MTLB biofilm, and polyethylene surface showing higher RTs in TSB biofilm. The study could provide useful data in quantitative microbiological risk assessment of Salmonella, and supply information in improving the control measures of Salmonella.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2320-2326. https://doi.org/10.11869/j.issn.100-8551.2015.12.2320In order to provide a theoretical basis for application of antimicrobial peptides (AMPs) obtained from prickly ash (Zanthoxylum bungeanum Maxim) seed protein by pepsin hydrolysis in food and other fields, the solubility, foaming capacity and emulsifying property of antimicrobial peptides were investigated with respect to pH and temperature. The results showed that the AMPs had a better solubility (NSI>80%) at pH≥6 and the temperature from 30 to 50℃. The AMPs had better foaming capacity in acidic and alkaline conditions than in neutral condition, and it had good foam stability (≥82%) within 10min and at pH≥6. The AMPs had certain foaming capacity (≥40%) at a certain range of temperature from 35 to 55℃, and it can maintain good foam stability (≥73%) within 10min. The emulsifying property of AMPs decreased with rising concentration, while the emulsifying stability increased with rising concentration. The emulsifying property and emulsifying stability of AMPs were worst at pH4.0, emulsifying property was 2.44m2·g-1 and emulsifying stability was less than 22 min. The AMPs had a highly hydrophilic and its hydrophilic lipophilic balance (HLB) value was greater than 16.7. This paper provide a theoretical basis in the field of food for the prickly ash seed protein AMPs.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2327-2333. https://doi.org/10.11869/j.issn.100-8551.2015.12.2327To scientifically breed more new tea cultivars to process white tea, seven different new Danxia varieties (lines) from Renhua (Guangdong Province), were studied in the project as the materials. The relationship between the content of main chemical components and the sensory quality of the processed tea was analyzed in two aspects: the biochemical difference among the varieties and the biochemical changes in the processing. The results showed that the main chemical components were significantly different among the varieties. The processed teas all had distinctively quality. Compared with the steamed samples, the tea polyphenols and soluble sugar content decreased significantly in processed tea. While the free amino acids just increased notably in made tea. Total catechins content, including both ester-and non ester-catechins, were lower than steamed samples. Based on the results of partial correlation analysis, the polyphenol-to-amino acid ratio (Pp/AA ratio) and the soluble sugar-to-caffeine ratio (Su/C ratio) had the significantly relevance with quality scores of the white tea. The Pp/AA ratio in steamed leaves and Su/C ratio in made tea gave positive effects on quality of white tea. The optimum equation on tea quality was established based on linear regression analysis. The researches provide new insights in evaluation the tea adaptability.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2334-2342. https://doi.org/10.11869/j.issn.100-8551.2015.12.2334In order to optimize the technology of combined osmotic dehydration and tunnel microwave drying of Pleurotus eryngii, the study was firstly conducted on the effects of immersion time, microwave power and transfer rate on the rehydration ratio, lightness (L*), polysaccharide retention rate and unit energy consumption indexes, with the method of three-factor quadratic orthogonal rotational combination design. The corresponding results showed that the effects of immersion time, microwave power and transfer rate on the rehydration ratio, lightness (L*), and polysaccharide retention rate were all significant. The unit energy consumption was affected significantly by immersion time, but not significantly by microwave power and transfer rate. On this basis,the quadratic regression models of four indexes were then deduced from obtained experimental data. Further, the variables were analyzed using response surface methodology (RSM). The optimized combined drying conditions were obtained with immersion time of 128 min, microwave power at 7.2 W·g-1 and transfer rate at 480 r·min-1. The research results may provide a theoretical basis for the industrial combined osmotic dehydration and tunnel microwave drying of Pleurotus eryngii.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2343-2348. https://doi.org/10.11869/j.issn.100-8551.2015.12.2343The comprehensive use of of peel and pomace of Citrus Paradisi cv.Changshanhuyou in China is of importance considering the increase of economy benefit and the decrease of environmental pollution, the objective of this experiment is to study the techniques for extraction, separation and purification of the active components, flavonoids and limonin, in the peel and pomace of Citrus Paradisi cv.Changshanhuyou, and to preliminarily assess their hypolipidemic effects. Optimized techniques for extraction and purification of flavonoids and limonin from the peel and pomace of Citrus Paradisi cv.Changshanhuyou was established, i.e. the dried peel and pomace was ground and extracted with 95% ethylthanol for 5 hours, then the extract passed through a column of macroporous resin, which was then washed with 40% ethanol. Finally the washing solution was dried with rotary evaporator to obtain the active products. The extraction rate was about 0.95% and the purity was about 86% to 99%. From the result of experiment on inhibition of the activity of pancreatic lipase, it was shown that the purified products presented obvious hypolipidemic effects. Finally, some small specimens with capsule shape had been prepared. The experiment would be providing a pathway for utilization of peel and pomace of Citrus Paradisi cv.Changshanhuyou.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2349-2354. https://doi.org/10.11869/j.issn.100-8551.2015.12.2349In order to improve the objectivity, reliability and repeatability of Mucoe-type Douchi on quality review, reduce human differences of evaluation, in this paper,all samples were analyzed and tested with an electronic nose and an electronic tongue; then principal component analysis was applied for evaluating the effect of differentiation and verified by sensory evaluation; then it was concluded that the electronic nose did not effectively differentiate samples under wet steam while effectively on samples under dry steam. The electronic tongue could differentiate samples under both wet steam and dry steam effectively; the Mucor-type Douchi samples wet steamed for 35 minutes under 121℃ were closer to Laba bean samples wet steamed for 25 minutes under 135℃ and their tastes were similar to certain extent; Mucor-type Douchi samples dry steamed for 25 minutes under 105℃ were considerable different from other samples, which means its taste was significantly different from those of other samples, so it has great relevance between the taste of Douchi and cooking conditions. The results of evaluation showed that the electronic nose and tongue had ahigher identification degree and more accurate and objective results than sensory evaluation. This study provided a theoretical basis for standardized production and optimization of production conditions for Mucoe-type Douchi.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2355-2359. https://doi.org/10.11869/j.issn.100-8551.2015.12.2355The yeast extract was irradiated by 60Co-γ of 0 to 10kGy dose range and the sensory quality,amino acid content and microbial survival rate of YE were detected before and after irradiation to study the maximum tolerated dose and the minimum effective dose.Results showed that when the three batches of YE (TB11,FB00 and FA03 )were irradiated of 1.5,3.0 and 4 kGy respectively,the microorganisms content was according with enterprise standard. There was obvious irradiation odor when irradiation dose was higher than 7kGy.The colority,taste and amino-acid content of the yeast extract had no obvious change when irradeation dose was lower than 8kGy.The bacteria D10 of yeast extract was 0.7kGy and the maximum tolerated dose was 7kGy and the absorption dose uniformity of the product box was 1.69,so the minimum effective dose of yeast extract was not more than 4.1kGy. So,the initial bacterial quantity must be controlled within 7.6×106CFU·g-1. The research for the application of yeast extract irradiation sterilization technology provide the process parameters.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2360-2365. https://doi.org/10.11869/j.issn.100-8551.2015.12.2360In this paper, cold-stored red-heart plum(P. Salicina Lindl.)total soluble solids (TSS) predicting method using electronic nose (e-nose) was studied in order to realize quality non-destructive analysis. TSS contents of plum samples from the same batch were examined according to the Chinese national standard method. E-nose responses were also measured. Non-linear stochastic resonance (SR) was used to extract e-nose signal-to-noise ratio (SNR) eigen values for red-heart plum TSS content non-linear Boltzmann predicting model development. Results demonstrated that the red-heart plum TSS content predicting model of correlation coefficent R2=0.9700, indicated that e-nose successfully predicted the TSS content of the plums. This model presented high forecasting accuracy and gave accurate predictions for tested samples. The proposed method presented some advantages, such as rapid response, high accuracy, and low cost, etc. This work provided theoritical reference for fruits and vegetables quality e-nose rapid and non-destructive analysis.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2366-2374. https://doi.org/10.11869/j.issn.100-8551.2015.12.2366Techniques for extraction the volatile compounds from the food matrix provide a prerequisite basis for food flavor research. The mechanism and principle of four kinds of extraction techniques, including solvent extraction, distillation, headspace trapping and sorptive extraction were described in this article. The advantages and disadvantages of these representative methods and their application in food flavor research are summarized,with particular focus on the solid phase micro-extraction and stir bar sorptive extraction techniques that have been widely applied in food flavor research in recent years. In view of the above knowledge, we proposed the development trend for volatiles extraction. The information collected here provided constructive suggestions for investigators engaging in the field of food flavor research.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2375-2384. https://doi.org/10.11869/j.issn.100-8551.2015.12.2375It is great significant for the reasonable application of Se fertilizer and the production Se-enrich rice to study of the relationship between soil Se content, growth and Se accumulation of rice. Effect of soil Se (total Se levels of 0.46 to 9.22 mg·kg-1; available Se levels of 0.11 to 0.73 mg·kg-1) and applying Se fertilizer on biomass, antioxidative responses and Se accumulation of rice were investigated under the condition of soil pot culture. Results showed that the rice had the range of 0.20 to 1.50 mg·kg-1 of Se contents, which could meet or surpass the national standard of Se-enriched rice, and application of Se fertilizer significantly increased the Se content of each part of the rice by 0.71 to 16.36 times. In addition, application of Se fertilizer increased rice yield by an average of 17.61%, SOD, POD, CAT activity and MDA content by an average-19.54%, 41.34%,1.83% and-0.59%, respectively, and the content of MDA. Correlation analysis showed that soil available Se content was positively related to the Se content of each part of rice of different stages (when Se was not applied), but negatively related to Se content increased by Se fertilizer application. However, soil total Se was only related to the Se content of shoot and husk at mature stage, not to the Se content in polished rice. Levels of both soil total Se and available Se content were positively related to MDA without Se fertilizer, but negative to the percentages of Se increase by Se application. The results showed that the level of soil available Se content was a good indicator of Se-enriched rice production.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2385-2393. https://doi.org/10.11869/j.issn.100-8551.2015.12.2385In order to obtain effects on molybdenum enzymes, carbon and nitrogen metabolism process of tobacco, the effects on molybdenum enzymes, carbon/nitrogen metabolism key enzymes and their related metabolites of Nanjiang 3 tobacco were studied under molybdenum deficiency stress(+Mo and-Mo)used by nutrient solution method. Results showed that, when cultured for 10d, the molybdenum enzymes and carbon/nitrogen metabolism enzymes (xanthine dehydrogenase, nitrate reductase, glutamine synthetase, amylase, sucrose phosphate synthase and invertase) of molybdenum deficiency tobacco-Mo were higher than those of 0d, but the difference between molybdenum application and molybdenum deficiency tobacco was observed insignificant; when cultured for 20d, except for sucrose phosphate synthase, other enzymes content or activities were declined,between the two treatments significant and difference was found. And the sucrose and protein content of molybdenum deficiency tobacco were lower than those of molybdenum application tobacco,but the nitrite content was significantly higher than that of molybdenum application tobacco when cultured for 30d, molybdenum enzymes and carbon/nitrogen metabolism enzymes content or activities were steady for molybdenum application tobacco,but those of molybdenum deficient tobacco decreased. It is suggested that molybdenum deficiency reduces molybdenum enzyme activity or content significantly in tobacco, inhibits the nitrogen metabolism, but promotes the conversion metabolism of nitrogen to carbon and makes the leaves turn yellow in advance. This study provides precise physiological and biochemical information of harmonizing nitrogen/carbon metabolism of tobacco.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2394-2401. https://doi.org/10.11869/j.issn.100-8551.2015.12.2394The aim of this study was to investigate effect of straw returning on crop yield and nitrogen uptake and utilization efficiency of wheat rice rotation system. There are low nitrogen use efficiency and the high production of crop residues and improper handling of straw caused a series of environmental pollution in wheat-rice rotation system of Chengdu Plain. A field experiment was conducted to study the effect of different amount of straw incorporation on grain yield, dry matter accumulation and nitrogen use efficiency in wheat wheat-rice rotation system. No fertilizer, chemical fertilizer and no straw incorporation (control), chemical fertilizer and total straw incorporation, chemical fertilizer and half of straw incorporation, and chemical fertilizer and 1.5 times straw incorporation were investigated. Results showed that compared with no straw mulching treatment, straw incorporation could increase the grain yields of wheat and rice, wheat yield increased by 8.4% to 19.6%, and wheat yield-raising range improved with the amount of straw increasing; rice yield increased by 4.3% to 17.1%, and rice yield-raising range reduced with the amount of straw increasing. Comparing with no straw incorporation treatment, the results also indicated that straw incorporation promoted the growth of wheat and rice, and increased nitrogen uptake and grain nitrogen accumulation. The N uptake and grain nitrogen accumulation of wheat improved with the amount of straw increasing; straw incorporation inhibited rice growth and nitrogen uptake before the jointing stage, but acted reversely after the stage. The N uptake and grain nitrogen accumulation of rice reduced with the amount of straw increasing. Straw incorporation increased grain yield, N fertilizer use efficiency, and agronomic N use efficiency in straw incorporation treatments were higher than control by 10% to 13.8%, 19.5% to 26.7%, and 6.71 to 8.21 kg·kg-1 in the wheat rice rotation system respectively; Half straw incorporation (CT+0.5S) was the most advantageously treatment to improve the yield and nitrogen use efficiency under the experimental conditions, and compared half amount of straw (CT+0.5S) with full amount of straw (CT+1S), both of yield and nitrogen use efficiency both showed no significant difference. Considering the stock of straw resources, the crop yield and nitrogen use efficiency, we suggest that the full amount of straw incorporation (CT+1S) is suitable for rice wheat rotation system in Chengdu plain. The research findings will provide references for avoiding the pollution of environmental pollution caused by large amount of crop straw.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2402-2409. https://doi.org/10.11869/j.issn.100-8551.2015.12.2402In order to provide scientific basis for high yield and efficient maize cultivation, a field experiment was carried out at Yanjin institution of agricultural sciences in 2013 growth seasons, using two high-yield maize cultivars, Zhengdan 958 and Xianyu 335. Four nitrogen application rates were arranged with 0 kg·hm-2, 180 kg·hm-2, 240 kg·hm-2 and 300 kg·hm-2, marked as N0, N1, N2 and N3, respectively. The objective of this study was to study dry matter accumulation and yield benefit of two maize cultivars under different nitrogen regimes. The results showed that with the increase of N application rate, grain yield and economic benefits in two maize varieties increased, and grain yield and economic benefit in N2 treatment was the highest for both cultivars. Under different N regimes, grain yield and economic benefit of Xianyu 335 was higher than that of Zhengdan 958. As the growing stage delayed, leaf area index decreased in both cultivars. With increasing of N application rate, leaf area index in two maize varieties were increased. Under different N regimes, leaf area index of Xianyu 335 was higher than that of Zhengdan 958. With the increase of N application rate, population dry matter accumulation in two maize varieties have no significant difference before anthesis, while significant difference was found after anthesis. Dry matter accumulation amount after anthesis in N3 treatment was highest in both cultivars, while distribution rate was highest in N0 treatment. Under different N regimes, dry matter accumulation amount and distribution rate after anthesis of Xianyu 335 was higher than that of Zhengdan 958. These results indicated that reasonal N regimes had higher grain yield and economic benefits. The above results will provide reference and induction for efficiently cultivation of maize in summer.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2410-2417. https://doi.org/10.11869/j.issn.100-8551.2015.12.2410In order to enhance production of potato as pillar industry in arid and semi-arid areas of Ningxia, and find a new way to solve drought and water shortage, especially at seedling stage of potato growth process, a field study was conducted to determine effects of super absorbent dosages on soil physical properties of dryland and potato yield by using two dosages of super absorbents (Wote and Microbe). The results showed that, the soil bulk density of the 0 to 30 cm depth was significantly decreased by 9.0% compared with no aquasorbent applying (CK) under using Wote super absorbent for 90 kg·hm-2, but it greatly improved total soil porosity of the 30 to 60 cm depth by 8.9% with using Microbe super absorbent for 90 kg·hm-2. The Microbe super absorbent treatments produced higher amounts of>0.25-mm macroaggregates compared with CK at the 0 to 30 cm depth. In contrast, the Wote super absorbent treatments produced higher amounts of>0.25-mm microaggregates at the 30 to 60 cm depth. The super absorbent treatments obviously increased the amount of soil water stored at the 0 to 100 cm depth during the critical growing stage of potato, and the Microbe super absorbent treatments improved soil water status best at early stage of potato. However, the Wote super absorbent treatments could significantly improve soil water status at expansion-maturity stage. Higher yield improvements were achieved with using two dosages of super absorbents compared with CK. The yield of potato was increased by 41.1% with using Wote super absorbent for 60 to 90 kg·hm-2, and the commodity rate improvements was 21.1% with using Wote super absorbent 60 to 90 kg·hm-2, when compared with no aquasorbent applying respectively. This study could provide some reference for rational application of super absorbent in potato production in dry farming region of Ningxia.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2418-2424. https://doi.org/10.11869/j.issn.100-8551.2015.12.2418Effects of foliar fertilizers with different acidities phosphorus (P) forms on P absorptions and root morphologies of peanut (Arachis hypogaea L.) were investigated in the present study. P foliar fertilization experiment was conducted under artificial climate chamber in the study. The P foliar fertilizers with pH 5, pH 7 and pH 9 were sprayed to study the changes in P absorption-allocation and root morphological characteristics on seedling stage of peanut. Results showed that P foliar fertilizer under pH 7 increased significantly the P concentrations in leaf and stem by 46.9% and 25.7%, respectively. The P concentrations in leaf and stem were also promoted under pH 9, but it was lower than pH 7. P foliar fertilizers with different pH changed P absorption-allocation rates in root-stem-leaf systems. High pH (7 or 9) significantly decreased the P absorption amount and rats in roots, whereas it promoted the P absorption amount and rate in stem and leaf of peanut. P foliar fertilizer with high pH restricted the growth of root (especially the root length and surface area under root diameter<1.0 mm, and volume under root diameter>0.5 mm), while root length, surface area and volume were decreased by 172.6 to316.0cm, 72.8 to 96.6 cm2 and 3.1 to 3.5 cm3 per pot under pH 7 and pH 9 compared with pH 5. Therefore, spraying the neutral or alkaline P foliar fertilizer improved the P absorptions by aboveground parts of peanut seedling, while restricted the growths of root systems and decreased the needs of P by changing the root morphology. This study will provide a scientific basis for the high-efficiency use of P nutrient resources and rational fertilization for peanut.
-
Journal of Nuclear Agricultural Sciences. 2015, 29(12): 2425-2432. https://doi.org/10.11869/j.issn.100-8551.2015.12.2425In order to study the effects of root exudates on the growth of flue-cured tobacco,by using three exogenous chemicals(benzoic acid, salicylic acid and nicotine)to simulate the effects of root exudates of flue-cured tobacco on the growth of flue-cured tobacco seedlings, these three exogenous chemicals' main components are the same with root exudates of flue-cured tobacco,and analyze the impact of differences among three exogenous chemicals. The results showed that these substances,including benzoic acid, salicylic acid and nicotine,their concentration range of promoting flue-cured tobacco seedling root growth mainly is in 0 to 200 μmol·L-1、0 to 400 μmol·L-1 and 0 to 800 μmol·L-1(Root surface area was 1000 μmol·L-1 stomatal conductance and transpiration rate reached 600 μmol·L-1), and the concentration range of promoting chlorophyll fluorescence parameters of flue-cured tobacco mainly is in 0 to 200 μmol·L-1、0 to 800 μmol·L-1 and 0 to 800 μmol·L-1.However, in the concentration of 200 μmol·L-1,the actual photosynthetic efficiency of PS(II) of three exogenous substances could reach a maximum. In the process of the growth of flue-cured tobacco, these three exogenous chemicals, including benzoic acid, salicylic acid and nicotine, had impacts on morphological structure,photosynthetic characteristics and chlorophyll fluorescence parameters, and the impact is mainly in the two situation:promoting in the situation of low concentrations and inhibition in the situation of high concentrations, and the higher concentration,the greater inhibition,but different components have different effect on the Flue-cured Tobacco Seedling Growth. The concentration range of promoting the growth of flue-cured tobacco show nicotine > benzoic acid > salicylic acid.The research can provide the theoretical basis for solving the continuous cropping obstacle of flue-cured tobacco.
