运用现代生物技术防治作物病虫害

简要介绍了防治作物病虫害的现代生物技术的最新研究进展，包括一种转基因水稻新品种、激活抗性基因增强作物免疫力、人工合成杀虫基因以及含有蝎毒基因的杀虫病毒等。     

微生物降解稻草制取多种糖的研究

采用固态发酵的方式利用黑曲霉、康宁木霉、里氏木霉、绿色木霉、宇佐美曲霉5种真菌对稻草进行降解，利用高效液相色谱对降解产物中多种糖的种类与数量进行测定，为这些糖的继续利用提供参考价值。研究表明，稻草的降解产物中含有葡萄糖、阿拉伯糖、木糖、半乳糖和纤维二糖，其中葡萄糖占总糖的比例最大。     

有机肥对水稻的肥效试验分析

水稻生产每1／15公顷施用等量N(11．15kg)、P2O5(3．13kg)、K2O(9kg)的丰都有机肥(养分含量为11，3，7)、挪威复合肥(15，15，15)、百康通用肥(12，5，8)，在相同管理水平下，肥效差异不明显。     

Ni在水稻各部位累积规律的研究

通过盆栽试验，研究了吉林省砂质水稻土中Ni的单元及复合污染时水稻对Ni的吸收累积规律。结果表明，单元污染下Ni在水稻根、茎和糙米部位的分配比为200：9：1，而复合污染下分配比为107：9：1，说明在其他金属的作用下Ni易向水稻的地上部分转移，通过统计分析可以看出，Pb能促进水稻根和糙米对Ni的吸收，降低水稻茎对Ni的吸收；As能促进水稻各器官对Ni的吸收，Cu能降低水稻根和茎对Ni的吸收，促进糙米对Ni的吸收,在向可食部位转移过程中，As，Ni和Pb之间及Cu和Ni之间都是协同作用。     

用ELISA检测稻飞虱的捕食性天敌

利用酶联免疫吸附试验（ＥＬＩＳＡ）方法测定了不同种类的捕食性天敌的阳性反应率．发现稻飞虱不同发育阶段的蛋白质组成一致，所有捕食性天敌种类中以食虫沟瘤蛛、拟水狼蛛的阳性反应率最高     

三系杂交稻博优64和两系不育系HUTB2S组培快繁的研究

本文报道了利用组织培养手段快速繁殖三系杂交稻博优64和两系不育系HUTB2S的研究结果.由剥去了内稃和外稃的米粒经无菌发芽获得实生苗,以实生苗为外植体,成功地实现了快速繁殖.在组培条件下,水稻无菌实生苗可以反复分株继代增殖.试验了N6、MS、H、1/2MS、BS、SJ-1等6种基本培养基,用于促进分蘖的效果依次为N6>MS>H>1/2MS>BS>SJ-1.在被试的KT、6-BA和ZEA等3种细胞分裂素类激素中,KT最适合用来促进分蘖.促进分蘖的最适蔗糖浓度范围9%~12%.在高蔗糖浓度(9%~12%)和高KT浓度(8~10mg/L)条件下,水稻无菌苗不仅分蘖多,植株健壮,而且根系发达.水稻组培苗移栽至大田后长势旺盛,长相一致,目前尚未发现明显的性状变异.     

响应面法对Neutrase蛋白酶酶解燕麦麸的优化研究

以燕麦麸皮为原料,采用Neutrase中性蛋白酶对其进行水解,以蛋白水解度及氮溶指数为评价指标,在反应时间、加酶量、料液比等单因素实验的基础上,采用Box-Benhnken响应面分析法系统探讨了燕麦麸蛋白酶解的最优条件,当水料比为15∶1,加酶量为底物的5%,酶解反应时间为4 h,水解度可以达到12%,氮溶指数达到59%.     

β-Glucosidase treatment and infestation by the rice brown planthopper Nilaparvata lugens elicit similar signaling pathways in rice plants

β-Glucosidase has been reported to induce the production of herbivore-induced plant volatiles. However, how it works remains unclear. Here, we investigated the levels of salicylic acid （SA）, jasmonic acid （JA）, ethylene, and H2O2, all of which are known signaling molecules that play important roles in induced plant defense in rice plants treated with β-glucosidase, and compared these to levels in plants infested by the rice brown planthopper Nilaparvata lugens （Stal）. Results showed that wounding and treatment by β-glucosidase increased the levels of SA, ethylene, and H2O2, but not JA, in all plants compared to control plants. The signaling pathways activated by β-glucosidase treatment are similar to those activated by an infestation by N. lugens, although the magnitude and timing of the signals elicited by the two treatments are different. This may explain why both treatments have similar volatile profiles and are equally attractive to the parasitoid Anagrus nilaparvatae Pang et Wang.     

Genetic dissection of a thousand-grain weight quantitative trait locus on rice chromosome 1

Thousand-grain weight （TGWT） is an important factor affecting grain yield as well as grain quality in rice. A quantitative trait locus （QTL） qTGWTI-1 for TGWT was detected previously near DNA marker RG532 on the short arm of chromosome 1 in a recombinant inbred line （RIL） population derived from the indlca-indica rice cross Zhengshan97B （ZS97B）/Milyang46 （MY46）. In this study, two residual heterozygous lines （RHLs）, Chl and Ch2, derived from the ZS97B/MY46 RIL F7 population, were used to develop two Fe populations, RIL-1 and RIL-2. The genome of Chl and Ch2 contains a heterozygous region flanked by RM1--RM3746 and RM151--RM243 on the short arm of chromosome 1, respectively, but is homozygous in other regions. Two tightly linked QTLs, Gwl-1 and Gwl-2, with the same additive direction and similar effect on TGWT, were detected in the region of QTL qTGWTI-1 in population RIL-2. No QTL was detected in the population RIL-1. Four individual RHLs from the population RIL-2 carrying heterozygous segments flanked by RM151--RM10404, RM10381--RM243, RM10435--RM259 and RM10398--RM5359, respectively, were chosen to develop four F= populations. Ten maternal homozygotes and 10 paternal homozygotes were selected from each of the four F2 populations derived from the four RHLs. The four sets of near isogenic lines （NILs） were grown for phenotyping of TGWT and delimitation of Gwl-1 and Gw1-2. Results showed that Gwl-1 and Gw1-2 were located in the intervals RM10376--RM 10398 and RM10404--RM 1344 which cover 392.9 and 308.5 kb regions, respectively. The enhancing alleles were from ZS97B at both loci, and no significant interactions were detected. Genetic dissection of Gwl-1 and Gwl-2 has laid a foundation for their cloning and molecular breeding of grain yield and quality in rice.     

Southern rice black-streaked dwarf virus:A new proposed Fijivirus species in the family Reoviridae

For the past several years, a novel dwarf disease has been observed on rice (Oryza sativa) in some regions of Guangdong Province and Hainan Province, southern China. Infected plants showed stunting, dark leaf and small enations on stem and leaf back. Typical Fijivirus viroplasma containing crystalline arrayed spherical virons approximately 70―75 nm in diameter and tubular structures were detected in ultrathin sections by an electron microscope in parenchyma phloem cells of the infected plants. The virus was transmitted to rice seedlings by white-backed planthoppers, Sogatella furcifera (Hemiptera: Delphacidae), collected in the diseased fields. Analysis of dsRNA extracts from infected plants revealed ten linear segments, which were similar to the electrophoretic profile of Rice black-streaked dwarf virus (RBSDV). RT-PCR with a single primer which matched to a linker sequence ligated to both 3′ ends of the viral genomic dsRNAs resulted in amplification of genome segments 9 (S9) and 10 (S10) cDNA products. The complete nucleotide sequences of S9 and S10 were obtained from clones of the RT-PCR amplicon exhibited characteristic properties of Fijivirus including low GC content (34.5% and 35.6%), genus conserved 5′ and 3′ termini sequences and similar genome organization. Blast searches indicated that the sequences of S9 and S10 shared 68.8%―74.9% and 67.1%―77.4% nucleotide identities with those of viruses in the Fijivirus group 2, respectively. These values were similar to those among other viruses in the Fijivirus group 2 and considerably lower than those among RBSDV isolates. Phylogenetic trees based on S9 and S10 nucleotide sequences and their putative amino acid sequences showed that this virus represented a separate branch among other Fijiviruses. The virus was also detected by a nested RT-PCR assay in corn (Zea mays), barnyard grass (Echinochloa crusgalli), Juncellus serotinus and flaccidgrass (Pennisetum flaccidum) in and/or adjacent to the infected rice fields. It is proposed that this virus be considered as a new species, Southern rice black-streaked dwarf virus, in the group 2 of the genus Fijivirus in the family Reoviridae.