Comparative Study of Immunological Properties on Glutamine Synthetase Isozymes in Rice Plants

In rice (Oryza sativa L.) roots two glutamine synthetase (GS) isozymes, GSra and GSrb, were identified recently in the author's experiments, but the homology of both GSra and GSrb as well as their localization in the rice roots are unclear. In the present study, the purified GSra and GSrb from rice roots were used to immunize rabbits to obtain the respective antibodies. The immunodiffusion and immunoblotting experiments showed that the antibody against GSra or GSrb was specific for GS and its isozymes. The immunoprecipitation test indicated that the antibody of GSra or GSrb not only recognized its respective antigen, but also well recognized each other's antigen. GSra or GSrb antibody recognized also better cytosolic GS1 of rice leaves, but the recognization for chloroplast GS2 from rice or spinach (Spinacia oleracea Mill.) leaves was weaker. Our results indicate that GSra and GSrb from rice roots are quite similar in antigenicity and are extremely similar proteins and that both GSra and GSrb may also be a form of cytosolic GS just as the cytosolic GS1 of rice leaves.

Analysis of Gene Expression of Seven Isoforms of ADP-glucose Pyrophosphorylase in Rice Endosperm under Different Temperature Conditions

[Objective] This study aimed to analyze the effects of temperature on the expression of AGPase isoform genes in rice endosperm during milk stage. [Method] Different temperature treatments （33 and 25 ℃ of daily mean temperature for high and normal temperature treatments, respectively） and the real-time fluorescence quantitative PCR （ FQPCR） were used to analyze the expression patterns of seven isoforms （AGPS1, AGPS2a, AGPS2b, AGPL1, AGPL2, AGPL3 and AGPL4） of ADPglucose pyrophosphorylase （AGPase） which was the key enzyme in starch synthesis and metabolism in rice endosperm of two rice varieties Teqing and Thai Fragrant Rice. [Result] The AGPase isoforms AGPS2b, AGPL2 and AGPL3 had much higher expression than the other four isoforms, thus they were thought to be the main expression patterns of AGPase in rice endosperm. The relative expressions of AGPL2 was the highest among all the isoforms. The relative expressions of AGPS2b, AGPL2 and AGPL3 were higher in the normal temperature treatment than in the high temperature treatment in both rice varieties. The relative expression of the three enzyme genes in milk stages in Teqing was higher than those in Thai Fragrant Rice under different temperature treatments. [Conclusion] This study provides a theoretical basis for further use of molecular biology techniques to cultivate stable high-quality rice varieties.

遗传的基本规律热点关注

1．热点追踪 1．热点信息南方农村报2005年4月2日报道,由“杂交水稻之父”袁隆平院士亲自主持的深圳龙岗超级杂交稻育种基地,今年将向亩产900公斤的目标作最后冲刺!国家杂交水稻工程技术研究中心清华深圳龙岗研究所有关负责人日前透露。

Construction of a full bacterial artificial chromosome(BAC) library of Oryza sativa genome

We have constructed a full BAC library for the superior eaxly indica variety of OryZa sativa, Guang Lu Ai4. The MAX Efficiency DHlOB with increased stabilltyof inserts was used as BAC host cells. The potent pBelo BACII with double selection markers was used as cloning vector. The cloning efficiency we have reached was as high as 98%, and the transformation efficiency was raised up to 1Oo transformants / pg of large fragment DNA. The BAC recombinant transformants were picked at random and analyzed for the size of inserts, which turned out to be of 120 kb in length on average. We have obtained more than 20,000 such BAC clones. According to conventional probabillty equation, they covered the entire rice genome of 420,000 kb in length. The entire length of inserts of the library obtained has the 5- to 6- fold coverage of the genome. To our knowledge, this is the first reported full BAC library for a complex genome.

Rice industrial economy and its development strategy

On the basis of the analysis of the present situation of food grain and rice production in China, countering the beginning tendency to neglect rice production because of rice grain structural surplus and low market price after China’s agriculture entering the new development stage, this paper puts forward the concept of rice industrial economy, explains its attribute, connotation, key factors, etc., forms the basic idea of developing the rice industrial economy, and suggests some strategic measures such as regionalized layout of rice production,etc. to develop the rice industrial economy.

Quality Assessment of Different Industrial Effluents for Irrigation in Agriculture

A laboratory experiment was undertaken in Soil Science Division of BRRI （Bangladesh Rice Research Institute） during 2010 to assess the quality of industrial effluents and city waste as a source of irrigation water for agriculture. The treatments of the studies were the effluents of five different industrial sources like polyvinyl, dyeing, pharmaceuticals, beverage, tannery, mixed waste water （contaminated with effluents from many industries）, CWW （city waste water） and underground water as control. The industrial effluents, MWW （mixed waste water）, CWW and control water were tested for electrical conductivity, pH, and soluble ions such as Na^＋, Ca^2＋, Mg^2＋, K^＋, HCO3-, CO3^2-, NH4^＋-N and H2PO4^-. Micronutrients （Fe, Mn, Cu and Zn） and heavy metals （As, Pb, Cd, Cr and Ni） were analyzed from the samples. Beverage industry effluent showed acidic reaction, while the other industrial effluents showed alkaline reaction （pH 7.25-9.07）. Pharmaceutical, dyeing and tannery effluents showed EC of 3.40, 4.30 and 9.49 dS m^-1, respectively, compared to 0.54 dSm^-1 of the control. All the effluents except polyvinyl and beverage effluents and CWW recorded higher carbonate and bicarbonate content than that of control. Industrial effluents and CWW were higher in micronutrient content as compared to control. Dyeing, pharmaceutical and tannery effluents contained 2.51, 3.94 and 4.29 mg L^-1 lead, 0.15, 0.14 and 0.38 mg L^-1 chromium and 0.25, 0.24 and 0.16 mg L^-1 nickel, respectively which might be concemed for health hazard through food chain.

Molecular breeding of hybrid rice

This paper describes in a general way the objectives, contents and methods of molecular breeding, and the application of molecular breeding in hybrid rice.

Influences of the Paddy Rices with Different Moistures on the Head Rice Recovery

A major component rice variety of Xiangwanxian 9 (a late Indica variety) with 13.1%, 15.6% and 18. 3% of the moisture was respectively mixed with three ad-ditive varieties in 13% of moisture at ration of 7:3 for processing assorted rices. Head rice recovery of the treatments was determined 24 hours later. Analysis indicated sig-nificant differences exist in the effects produced by the component varieties, their moistures and the component variety moisture.

Process Optimization of Vacuum Fried Rice-Straw Mushroom （Volvariella Volvacea） Stem Chip Making

The study was aimed to obtain the optimum conditions for vacuum frying and predicting the moisture lost during rice straw mushrooms stem chip production. The raw materials were obtained from the local farmer around the campus. A completely randomized factorial experimental design and Duncan＇s multiple range tests were used to achieve the objectives. Three temperatures, i.e. 80, 90 and 100 ℃ and five frying time, i.e. 3, 6, 9, and 15 minutes with a 2 mm slice thickness were studied to determine the optimum condition and predict the moisture decrease. Results showed that the vacuum frying time in general affects the chips color and oil uptake significantly （p 〈 0.01） and correlated with the moisture decrease. The chips moisture content decline significantly after vacuum frying at 90 ℃ and 100 ℃ for 3 minutes. While for the 80 ℃ vacuum frying, the significant decrease of moisture occurred due to the increase of vacuum frying time from 3 to 6 minutes （p 〈 0.01）. The optimum conditions for a 2 mm slice thickness chips making are vacuum frying at 100 ℃ for 3 minutes. The chips moisture lost followed generally a two-stage of falling rate pattern during vacuum frying, and each could be well predicted by an exponential equation （R2 = 0.99）.

Long-Term Effect of Industrial Waste Water Irrigation on Soil Chemical Properties

A laboratory experiment was conducted in Soil Science Division of BRRI during 2011 aimed to determine the vertical distribution of soil chemical properties under long-term industrial waste water irrigated rice field. Waste water irrigated rice field seemed to create some differences in soil pH profile. The pHW and pHKCl in all soil depth was higher with waste water irrigated rice field. The surface charge of both the soils was considerably negative. Waste water irrigated rice field developed more negative charges in soils. Irrigation with waste water increased Electrical Conductivity （EC） in rice soils profile. The organic carbon content （%） started to decrease sharply with the increase in soil depth. Organic carbon content was higher with waste water irrigated rice soils Total nitrogen （%） was high with underground water irrigated rice soils in surface but at deeper, total N was similar in both soils. Olsen P （mg/kg） was higher with underground water irrigated soil at 0-5 cm depth but at 5-100 cm soils profile, it was higher with waste water irrigated rice soils. Micronutrients （Zn, Fe, Cu and Mn） and heavy metals （Pb, Cd, Ni and Cr） in soils were increased significantly through irrigation with waste water in rice-rice cropping pattern.

Amylose contents of cereals; influence of household processing on the amylose contents of these foods

Amylose is a food starch found in cereals, legumes and root vegetables. Keeping in view the importance of amylose for various food industries as well as its importance on domestic level, the current study was conducted to analyze the amylose content of common cereals e. g rice （sela, coarse and basmati）, maize yellow, Kisan and Azam varieties and wheat （Tatara, Fakhr-e-sarhad and Bakhtawar-92） varieties as well as quantifying the influence of cooking/boiling procedures on the amylose contents of cereals. The maximum amylose content were observed for wheat variety Tatara （24.28%） followed by Bakhtawar-92 （22.74%） and Fakhr-e-sarhad （19.77%）. Among maize and rice varieties studied, Kisan and course rice were rich in amylose content with values of 27.19 and 30.48% respectively. The chapti of Tatra wheat were scored highest for appearance （7.6）, flavor （7.5）, texture （7.6） and overall acceptability （7.55）. The roti of Kisan and Azam varieties got maximum appearance score of 7.6 as compared to 7.4 for maize yellow variety. Basmati rice was scored highest regarding appearance （8.4）, flavor （8.6）, texture （8.6） and overall acceptability （8.53. The moisture content ranged from 10.61 （Azam） to 8.01% （wheat variety Fakhr-e-sarhad）. Cooking reduced the amylose content of wheat bread from （19.77%-24.28%） to （15.47%-15.94%） with cooking time of 5 min, maize bread from （21.48%-27.19%） to （19.53 %-25.85%） with maximum cooking time of 10 min and boiled rice from （24.90%-30.48%） to （24.18%-30.19%） with cooking time ranging from 12 to 20 min. It can be inferred from these studies that the reduction in amylose content were more in chapti/roti preparation of wheat and maize varieties as compared to boiling of rice varieties and that significant varietals differences exist in amylose content of the uncooked samples.

Site-Specific Nitrogen Management in Dry Direct-Seeded Rice Using Chlorophyll Meter and Leaf Colour Chart

The need to maintain high rice yields and improve fertilizer nitrogen(N)-use efficiency has fueled the use of tools such as leaf colour chart(LCC) and chlorophyll meter(SPAD meter) in managing fertilizer N based on colour of the leaf. Field experiments were conducted during 2011 to 2013 at Ludhiana, India to assess the need for basal N application and to establish critical threshold values of leaf greenness as measured by LCC and SPAD meter for formulating strategies for in-season management of fertilizer N in dry direct-seeded rice(DDSR). Avoiding application of N at sowing did not adversely affect rice grain yield, indicating that basal N application in DDSR was not necessary and might lead to reduced N-use efficiency. Monitoring N uptake rate during the growing season of DDSR suggested that N uptake rate peaked at the two growth stages: maximum tillering(42 to 56 days after sowing(DAS))and panicle initiation stages(70 to 84 DAS). Using the Cate-Nelson procedure, critical LCC and SPAD meter values for fertilizer N application worked out to be 4 and 37, respectively. Real-time fertilizer N management strategy based on applying 30 kg N ha-1whenever SPAD meter or LCC readings fell below the critical values maintained optimum rice yields along with higher N-use efficiency than that observed by following blanket recommendation for fertilizer N in the region. The fixed-time variable-dose strategy consisted of applying prescriptive doses of 20 kg N ha-1at 14 DAS and 30 kg N ha-1at 28 DAS and corrective doses of 30, 40 or 50 kg N ha-1at 49 and 70 DAS depending upon LCC shade to be ≥ 4, 4–3.5, or < 3.5 and SPAD meter readings to be ≥ 40, 40–35, or< 35, respectively. This strategy also resulted in optimal rice yield along with higher N-use efficiency as compared to the blanket recommendation. This study revealed that in DDSR, fertilizer N could be managed more efficiently using the tools of LCC and SPAD meter than the current blanket recommendation.