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151.
以云烟87为试验材料,以小麦、黑麦草、豌豆、苕子、油菜、大蒜等作物以及冬闲作为烤烟前茬,研究不同前茬对攀枝花烟叶的产量及质量的影响。试验结果表明,前茬种植黑麦草、豌豆、油菜有利于种植出烤烟中棵烟;前茬种植黑麦草、苕子、油菜能收获更高的经济效益,但前茬冬闲和种植黑麦草、小麦更能彰显攀西烟叶清香型风格,生产上推荐烤烟前茬种植黑麦草。  相似文献   
152.
日光温室冬春茬番茄在我省是指10月中下旬播种育苗,12月下旬至翌年元月上旬定植,3月底始收,5月中下旬拉秧的一茬,是取得经济效益最高的一茬。现将定植后的管理技术介绍如下。1、温度管理定植后5-7天不放风,提高温度,促进缓苗;缓苗后,白天保持20-25...  相似文献   
153.
东方百合多茬栽培试验   总被引:2,自引:0,他引:2  
孙志文 《甘肃科技》2005,21(2):175-177
本试验在日光温室和现代温室中对东方百合荷兰进口种球于8月上旬定植,完成切花采收后,让种球在基质中渡过低温休眠期,然后升高温室内温度,让种球发芽、出苗、产花,观察记载有关指标数据。最后对两茬栽培情况进行统计分析比较。试验证明对东方百合的两茬栽培是可行的,降低了生产成本,提高了经济效益,具有实际生产意义。对个别品种进行了三茬栽培。  相似文献   
154.
稻纵卷叶螟迁飞现象的观察   总被引:4,自引:0,他引:4  
稻纵卷叶螟CnaghalocrocismedinalisGuenee自70年代以来上升为海南省水稻三大害虫之一.海南省澄迈县一年发生9代:第2、4、6、9代为本地虫源本地繁殖代;第5、7代为大部分外地虫源迁入代;第3、8代为本地虫源大部分迁出代.广东省阳春县一年发生7代:第1、4、6代为本地虫源,本地繁殖代;第2、5代为大部分外地虫源迁入代;第3、7代为本地虫源大部分迁出代.每当水稻正处在分蘖期迁入的世代为害较为严重.往往引起突发性猖獗为害;而迁出代则意外地为害轻微.  相似文献   
155.
Three genes encoding for fungal cell wall degrading enzymes (CWDEs), ech42, nag70 and gluc78 from the biocontrol fungus Trichoderma atroviride were inserted into the binary vector pCAMBIA1305.2 singly and in all possible combinations and transformed to rice plants. More than 1800 independently regenerated plantlets in seven different populations (for each of the three genes and each of the four gene combinations) were obtained. The ech42 gene encoding for an endochitinase increased resistance to sheath blight caused by Rhizoctonia solani, while the exochitinase-encoding gene, nag70, had lesser effect. The expression level of endochitinase but exochitinase was correlated with disease resistance. Nevertheless, exochitinase enhanced the effect of endochitinase on disease resistance when the two genes co-expressed in transgenics. Resistance to Magnaporthe grisea was found in all kinds of regenerated plants including that with single gluc78. A few lines expressing either ech42 or nag70 gene were immune to the disease. Transgenic plants are being tested to further evaluate disease resistance at field level. This is the first report of multiple of expression of genes encoding CWDEs from Trichoderma atroviride that result in resistance to blast and sheath blight in rice.  相似文献   
156.
To understand the antagonistic mechanism of the broad spectrum antagonistic Enterobacter cloacae B8,Tn5 transposon-mediated mutagenesis is performed using suicide plasmid pZJ25. Two mutant strains that lost antagonistic character are isolated. Tagging with kanr gene on Tn5,an antagonistic related DNA fragment, the F fragment, right of the Tn5 insertion site is cloned in a plasmid named pTLF,from one of the mutant strains B8F. The 733 bp F fragment is then sequenced after subcloning. Genomic DNA of the original B8 strain is isolated, digested with Pst I and ligated to Pst I cassette. DNA fragments left and right of the F fragment are amplified from the Pst I cassette library using cassette primer and specific primers designed according to known sequence. 1106 bp sequence left of the F fragment and 664bp sequence right of the F fragment are finally obtained. Bioinformatics analysis shows that the contig assembled from the sequences of the cloned antagonistic related DNA fragments of B8 encodes three ORFs and is homogeneous to admM,admN and admO genes of Pantoea agglomerans andrimid biosynthetic gene cluster (AY192157). The ORF, named anrF gene which encodes a polyketide synthase, knocked out by Tn5 insertion, is a homology of admM and the insertion site of Tn5 is at 214 bp upstream of the stop codon. It is concluded that the anrF gene is a gene related to the antagonistic activity of E. cloacae B8, and speculated that the antagonistic substance produced by B8 is an andrimid.  相似文献   
157.
Cytochrome P450 gene superfamily is widely involved in diverse processes of plant development and environmental responses including defense response to pathogens.We previously isolated a rice cDNA fragment in a DD-PCR screening for blast fungus-induced genes. In the current study, we isolated a CYP72A gene cluster consisting of 7 P450 CYP72A genes (CYP72A17-23) with the conserved cDNA sequence through the public rice genome data. There are total 14 putative CYP72A members in the rice genome, with high diversity at N-terminal sequences while high homology at C-terminal sequences of those 14 putative proteins. We analyzed expression profiles of the cloned 7 CYP72A genes during pathogen infection and development. The results showed that expression of CYP72A18, 19, 22 and 23 was differentially regulated in the incompatible and compatible interactions between rice and blast fungus. Except CYP72A20, a pseudogene, other 6 CYP72A genes also exhibited temporal and spatial expression patterns, respectively.These findings provide fundamental data for rice P450 gene function analysis.  相似文献   
158.
A rice male-sterile mutant OsMS-L of japonica cultivar 9522 background, was obtained in M4 population treated with ^60Co γ-Ray. Genetic analysis indicated that the male.sterile phenotype was controlled by a single recessive gene. Results of tissue section showed that at microspore stage, OsMS-L tapetum was retarded. Then tapetal calls expanded and microspores degenerated. No matured pollens were observed in OsMS-L anther locus. To map OsMS-L locus, an F2 population was constructed from the cross between the OsMS-L (japonica) and LongTeFu B(indica). Firstly, the OsMS-L locus was roughly mapped between two SSR markers, RM109 and RM7562 on chromosome 2. And then eleven polymorphic markers were developed for further fine fine-mapping. At last the OsMS-L locus was mapped between the two lnDel markers, Lhsl0 and Lhs6 with genetic distance of 0.4 cM, respectively. The region was delimited to 133 kb. All these results were useful for further cloning and functional analysis of OsMS-L.  相似文献   
159.
马拉硫磷对中华稻蝗等位酶基因型的致死作用   总被引:4,自引:0,他引:4  
将采自山西省代县阳明堡乡的中华稻蝗(Oxya chinensis)进行马拉硫磷急性毒性实验,并对所研究个体进行等位酶水平淀粉凝胶电泳,研究马拉硫磷毒性与中华稻蝗种群等位酶基因型之间的相关关系.结果表明:马拉硫磷毒性与中华稻蝗种群基因型之间存在相关关系,在所研究的磷酸葡萄糖异构酶(PGI)和苹果酸酶(ME)两种等位酶中,马拉硫磷对中华稻蝗等位酶PGI不同基因型个体有选择性致死作用.卡方分析显示,其中的一对基因型Pgi-ab和Pgi-bb之间存在显著的致死差异.  相似文献   
160.
"丰两优一号"是合肥丰乐种业公司与北方杂交粳稻研究中心共同育成的二系杂交稻新组合,具有优质、高产、抗性好等特点.经农业部稻米品质检测中心测定,该品种精米率、粒长、蛋白质含量等10项指标达优质米一级标准,长宽比、直链淀粉含量两项指标达优质米二级标准.该品种高抗白叶枯病,耐肥抗倒,生育期142天,在皖东稻区平均每公顷产量达9000~9300公斤,高产可达1.05万公斤,适宜推广种植.其高产栽培技术如下:  相似文献   
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