日本超级稻在粤北地区的引种试验

日本超级稻在粤北地区试种的结果表明:该超级稻在粤北地区栽培的生育期适中,其生育期为127d,比对照品种优优4480的生育期130d,早熟3d,并且该超级稻还具有产量高、丰产性好等特点,其产量比对照品种增产12.6%,结实率比对照品种高12.6%,适宜在粤北地区作为早造种植,可以进行扩大试种.     

Two closely linked rice U14 boxC/D snoRNAs

By analysis of the conserved elements in yeast U14 boxC/D snoRNA. the conserved elements in rice U14 boxC/D snoRNA have been speculated. Through computer search of the international rice genome database, two rice U14 snoRNA gene candidates are obtained. These two putative U14 snoRNA genes are closely linked on rice chromosome 2. The coding sequences of these two snoR-NAs exhibit the hallmark structure of boxC/D antisense snoRNA. They both have conserved boxC and boxD sequences and a 14nt-long complement to the sequence between 414nt and 427nt of rice 18S rRNA (according to GenBank accession no. X00755). The experimental evidence shows that these two snoRNAs are involved in the methylation of the complementary sequence of rice 18S rRNA. The existence and localization of these two snoRNAs are proved by RT-PCR and Northern blot. Further analysis shows that both of the newly found rice snoRNAs have high homology with maize U14 snoRNA. and they are named rice U14.1 snoRNA and U14.2 snoRNA respectively. The gene sequence encoding these two snoRNAs has been deposited in the GenBank database under accession number of AF332622.     

Transformation of japonica rice with RHL gene and salt tolerance of the transgenic rice plant

Overexpression of the yeast HAL2 gene increases salt tolerance of yeast and plant. Rice HAL2-like (RHL) gene was introduced into a japonica rice cultivar HJ19 with Agrobacterium tumefaciens-mediated transformation. Transgenic plants in R0 generation were selected on the principle of GUS-positive, RHL gene PCR-positive and normal growth. Hygromycin-resistant plants of some transgenic lines in R1 generation increased salt tolerance during the seedling and booting stage, being less damaged in the cytomembrane and stronger in leaf tissue viability under salt stress during booting period. Southern analysis of transgenic lines tolerant to salt in R1 generation showed that the RHL gene expression cassette had been successfully integrated into rice genome. Moreover, gene engineering breeding methodology and really salt-tolerant rice cultivar were discussed.     

调整陕南农业产业结构的基本思路与对策

农业产业结构调整对促进农村发展，农民增收具有举足轻重的作用。本文通过对陕南自然生态条件，资源优势和农业现状的分析，指出传统农业产业结构是制约当前陕南农村农业经济发展的主要因素，并针对其问题提出了调整陕南农业产业结构的基本思路，方向及应采取的对策。     

稻粉虱若虫空间分布型和抽样技术的研究

稻粉虱若虫空间分布型测定结果表明 :(1)频次分布检验结果为负二项分布和核心分布 ;(2 )聚集度指标测定为聚集分布 ;(3) Iwao的线性回归方程为 m* =0 .76 5 5 + 1.6 778m,属于聚集分布。在空间分布型研究基础上 ,探讨了资料代换模式、Iwao序贯抽样模型和最适抽样数模型     

强苯赛对水稻幼苗根系生长的影响

强苯赛浸种对水稻幼苗的根长、根重和根系体积都有促进作用,能提高根尖细胞分裂指数,能使胚根尖切段伸长和发根力增强,并能提高胚乳中淀粉酶活性和根系的呼吸强度。     

野栽杂交花培育种探讨

采用花药培养技术对普通野生稻白叶枯病广谱抗源RBB16与水稻品种垦系3号等一批杂交后代进行花培育种。接种花药79080个,平均愈伤组织诱导率7.94％,绿苗分化率15.08％,从获得一批野栽杂交后代的花培绿苗中选育出T209-1、14-5两个高产、或高抗白叶枯病的稳定新品系。研究表明野栽杂交花培育种技术是克服野栽杂交后代稳定难,育种周期长与加速野生稻资源利用的有效途径。     

啮齿动物对水稻产量损失的模拟研究

在水稻的不同生长期进行机械损伤,模拟啮齿动物的危害.结果表明:产量损失的程度随破坏性的增加而加剧,速度与破坏程度呈协同趋势.不同的生长期所产生的影响各异.苗期啮齿动物的破坏不影响产量的减少.分蘖期具有轻度影响.孕穗期始表现明显,以后各期逐渐加剧.水稻生长期对损害有不同程度的补偿作用.依据有害动物管理经济学的观点,稻田灭鼠的理论时间定为孕穗期以后.     

差异展示法鉴定GA3诱导的水稻差异表达的mRNA

赤霉素是植物生长发育过程中一类重要的调节激素，在水稻不育系上喷施合适浓度的ＧＡ３（赤霉素的一种）可以克服其包颈现象。运用反转录和聚合酶链式反应建立了一套旨在分离差异表达ｃＤＮＡ的差异展示方法。