摘要：In order to meet the agronomy demand for hybrid rice direct seeding,a novel precise pneumatic rice seed metering device was designed with groups of sucking holes plate,by which 3-4 seeds could be synchronously sucked and synchronously dropped into the paddy *** plate was divided into five sections:seed sucking,seed clearing,seed carrying,seed dropping,and blank *** seeds were sucked in sucking section by the vacuum,carried and rotated to the dropping section with the plate,blown away in dropping section by the positive pressure air,and thrown into the dropping *** influences of the hole diameter,vacuum degree,and clear-up equipment on precision of metering device were *** were conducted to investigate the seeding precision and simulate the field emergence rates on the indoor seeding *** subjects were pregnant Indic hybrid Peizataifeng under two kinds of moisture content(23.43%and 26.07%).Other experiment conditions included the vacuum degree of 2.60 kPa,the rotation speed of seed sucking plate of 30 r/min,three sucking holes with a diameter of 1.6 mm,and the seed layer thickness of 25 *** seeding results showed that,in condition of no more than two seeds per hill,the emergence probabilities under the two moisture contents were 11.82%and 11.95%,respectively,and in condition of 3-4 seeds per hill,the results were 64.81%and 65.84%,*** 2-5 seeds per hill,the results were 92.08%and 92.60%,*** the emergence probability was 80%,under the two moisture contents,the no seed per hill probabilities were 1.33%and 0.80%respectively;the probabilities with 3-4 seeds per hill were 56.13%and 56.40%respectively;the probabilities with 5 or more seeds per hill were 10.67%and 10.13%respectively;the probabilities with 2-5 seeds per hill were 87.60%and 88.13%*** results showed the simulated experiment was an efficient and economic method to assess the capability of pneumatic rice seed drilling metering

摘要：Over the past few years, three photorespiratory bypasses have been introduced into plants, two of which led to observable in creases in photos yn thesis and biomass yield. However, most of the experiments were carried out using Arabidopsis under controlled environmental conditions, and the increases were only observed under low-light and short-day conditions. In this study, we designed a new photorespiratory bypass (called GOC bypass), characterized by no reducing equivalents being produced during a complete oxidation of glycolate into CO2 catalyzed by three rice-self-originating enzymes, i.e., glycolate oxidase, oxalate oxidase, and catalase. We successfully established this bypass in rice chloroplasts using a multi-gene assembly and transformation system. Transgenic rice plants carrying GOC bypass (GOC plants) showed significant increases in photosynthesis efficiency, biomass yield, and nitrogen content, as well as several other CO2-enriched phe no types under both greenhouse and field conditions .Grain yield of GOC plants varied depending on seeding season and was increased significantly in the spring. We further demonstrated that GOC plants had significant advantages under high-light conditions and that the improvements in GOC plants resulted primarily from a photosynthetic CO2-concentrating effect rather than from improved energy balance. Taken together, our results reveal that engineering a newly designed chloroplastic photorespiratory bypass could increase photosynthetic efficiency and yield of rice plants grown in field conditions, particularly under high light.

摘要：The accomplishment of further optimization of crop productivity in grain yield and quality is a great *** size is one of the crucial determinants of rice yield and quality;all of these traits are typical quantitative traits controlled by multiple *** advances have revealed several molecular and developmental pathways that govern these traits of agronomical *** review provides a comprehensive summary of these pathways,including those mediated by G-protein,the ubiquitin–proteasome system,mitogen-activated protein kinase,phytohormone,transcriptional regulators,and storage product biosynthesis and *** also generalize the excellent precedents for rice variety improvement of grain size and quality,which utilize newly developed gene editing and conventional gene pyramiding *** addition,we discuss the rational and accurate breeding strategies,with the aim of better applying molecular design to breed high-yield and superior-quality varieties.

摘要：In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) were used to develop the mapping population. One hundred and fifty-eight microsatellite markers were selected to survey T65 and TISL2. RM13 on chromosome 5 was found to be polymorphic between them. Cosegregation indicated that RM13 was closely linked with locus S-b. Eleven RFLP markers were selected on the corresponding region from the genetic map of rice Genome Research Program (RGP) of Japan to convert into sequence-tagged site (STS) markers. Amplicon length polymorphism (ALP) was carried out, but none of them was found to be polymorphic between T65 and TISL2. Then PCR-based RFLP (PBR) was done using six 4-nucleotide recognizing restriction endonucleases. Polymorphism was detected when PCR products of R830STS and R2213SSTS were digested with Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 5.2 cM and 5.5 cM, respectively. These PCR-based markers could be directly used in marker-assisted selection. The technical system combining genetic mapping and PCR-based marker-assisted selection will facilitate the development of molecular breeding.

摘要：TAL （transcription activator-like） effectors from Xanthomonas bacteria activate the cognate host genes, leading to disease susceptibility or resistance dependent on the genetic context of host target genes. The modular nature and DNA recognition code of TAL effectors enable custom-engineering of designer TAL effectors （dTALE） for gene activation. However, the feasibility of dTALEs as transcription activators for gene functional analysis has not been demonstrated. Here, we report the use of dTALEs, as expressed and delivered by the pathogenic Xanthomonas oryzae pv. oryzae （Xoo）, in revealing the new function of two previously identified disease-related genes and the potential of one developmental gene for disease susceptibility in rice/Xoo interactions. The dTALE gene dTALE-xa27, designed to target the susceptible allele of the resistance gene Xa27, elicited a resistant reaction in the otherwise susceptible rice cultivar IR24. Four dTALE genes were made to induce the four annotated Xa27 homologous genes in rice cultivar Nipponbare, but none of the four induced Xa27-1ike genes conferred resistance to the dTALE-containing Xoo strains. A dTALE gene was also generated to activate the recessive resistance gene xa13, an allele of the disease-susceptibility gene Os8N3 （also named Xa13 or OsSWEETll, a member of sucrose efflux transporter SWEET gene family）. The induction of xa13 by the dTALE rendered the resistant rice IRBB13 （xa13/xa13） susceptible to Xoo. Finally, OsSWEET12, an as-yet uncharacterized SWEET gene with no corresponding naturally occurring TAL effector identified, conferred susceptibility to the Xoo strains expressing the corresponding dTALE genes. Our results demonstrate that dTALEs can be delivered through the bacterial secretion system to activate genes of interest for functional analysis in plants.

摘要：根据两个植物抗病基因N和RPS2中核酸结合位点 (NBS)和富亮氨酸重复区 (LRR)中的保守序列设计了一对特异引物 ,用PCR从具有水稻 (OryzasativaL .)改良所需要的许多优良性状的水稻近缘野生种菰 (Zizanialatifolia(Griseb .)***)的基因组DNA中扩增同源片段。PCR产物经克隆后 ,分别以菰和水稻的基因组DNA为探针 ,通过点杂交对所得克隆进行了分析。点杂交结果表明 ,在所分析的 6 0个克隆中有 2个克隆是菰专化的序列 ,即它们与水稻无杂交信号。基因组DNA的Southern杂交进一步证实了这 2个克隆的专化性。为了验证一些可能的“水稻_菰”渐渗杂交系是否确实含有源自供体菰的DNA ,以这 2个克隆为探针 ,与经EcoRⅠ酶切的 5个可能的渐渗杂交系进行了Southern杂交。结果表明 ,这 2个克隆均能检测出其中的一个系含有其同源序列。这一结果为曾经报道的经一种非常规有性杂交方法将菰DNA导入水稻提供了确凿的证据。

摘要：本文主要阐述一种无损数据压缩算法在网络传输方面的进一步研究,作为网络传输中的数据包,算法设计中不但要考虑方法的有效性,同时还必须充分考虑工程应用的可靠性,而防止误码扩散是算法可靠性设计中要解决的首要问题。本文在数据传输可靠性的阐述中,着重分析了有意义范围内的图像特征,利用可靠性自适应的预测方案,可得到较好的去相关效果,从而达到增强算法工程可靠性的特点。

摘要：[Objective] This study was to screen the economic or stable PCR system of rice and detect the generality of the selected system in different molecular markers based on PCR.[Method] With DNA extracted from rice leaves by CTAB method as the template,PCR system was optimized by L16(45)orthogonal design.[Result] Clear bands were amplified from 16 different combinations,but the amplification effects and yields had *** most economic and applicable system was as follows:20 ng DNA template,150 μmol/L dNT...

摘要：In order to investigate the change rule of rice seed germination rate dur-ing the storage, the effects of moisture content and storage temperature on Lianjing 7 rice seed germination rate were investigated. The 3×3 factorial design was adopt-ed. The test data was analyzed using SPSS. The results showed that after the Lianjing 7 rice seeds with moisture content of 14.5% were stored at 25 ℃ for 180 d, the germination rate stil reached 89%; after the rice seeds with moisture content of 11.5% were stored at 5 ℃ for 180 d, the germination rate was up to 96.6%; the rice seed germination rate was decreased gradual y with the prolonging of storage time; the moisture content and storage temperature were two key factors affecting the Lianjing 7 rice seed germination rate, and there was significant interaction be-tween moisture content and storage temperature.

摘要：Yihui1577 was bred after over 10 generations by crossing R16 and Yunan purple rice. Many new hybrid rice varieties have been bred with Yihui1577, of which Gangyou1577. Ilyou1577, Nyou1577 and Yixiang1577 were certified by Sichuan Crop Variety Release Committee, Gangyou1577 and Yixiang1577 were certified by National Crop Variety Release Committee. The series varieties bred with Yihui1577 have been used widely with accumulated area of 1,200,000 ha. By using Yihui1577 as breeding material, an excellent restore line Yihui3003 and some other restore lines, such as Yihui1979 and Yihui315 with good quality and combination ability have been bred. Analysis of combination ability and stability of restore line Yihui1577 was made by using agricultural experimentation and statistical approach. The combination ability analysis was made by not complete dual crossing method with 4 CMS lines and 6 restorer lines. It shows that the general combination ability effect value of Yihui1577 is 0.226, while Minghui63 is -0.113. So the general combination ability of Yihui1577 is prior to that of Minghui63. Stability analysis shows that the F value of Gangyou1577 is 1.81378, while Sanyou63 is 1.40327, both doesn＇t reach significant level. So Gangyou1577 has the same stability as *** same conclusion is got in the stability analysis of the breeds of II you 1577, Yixiang1577, Nyou 1577 and so on.