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Sang-Kuk Kim Shin-Young Park Kye-Ryung Kim Jong-Hee Shin Su-Yong Kim Hak-Yoon Kim In-Jung Lee 《Journal of Crop Science and Biotechnology》2012,15(4):305-310
This study was carried out to determine the pretreatment effect of proton beam irradiation on germination and pasting properties of starches in two rices. Mature and healthy seeds irradiated with 10 doses (0, 50, 100, 200, 300, 400, 500, 600, 700, and 800 Gy) for determination of LD50 and characteristics of germination were recorded at 14 days after irradiation. The rice seeds irradiated with five doses (0, 50, 100, 200, and 300 Gy) were used to evaluate the irradiation effects of pasting properties of starches. It showed that a lower survival rate in germinated rice seeds was observed above 300 Gy showing 31 and 35% in Ilpum and Hanmaum, respectively. The higher plant height and root length were also recorded in 50 and 100 Gy. Amylose content in proton beam irradiated with 50, 100, 200, and 300 Gy was significantly decreased in two rice cultivars. Peak viscosity, hot peak viscosity, cooling peak viscosity, and setback viscosity decreased with increasing proton beam dose levels. The degree of crystallinity was significantly increased with increasing proton beam dose levels. Consequently, it might be deduced that proton beam irradiation causes changes of starch properties affecting crystalline regions of starch granules, especially at high dosage irradiation. 相似文献
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采用不同浓度来自70%甲醇溶液的麦冬块根提取物对2种产自日本的稻瘟病菌生理小种菌株MAFF305480和MAFF101002的菌丝生长及其接种诱发水稻幼苗稻瘟病发生的抑制效果进行评价。试验表明:含有麦冬块根提取物的原液1/10,1/20,1/40以及1/80浓度都能明显抑制稻瘟病菌小种菌株(MAFF305480和MAFF101002)菌丝生长, 抑制率均56.4%以上, 对接种诱发稻瘟病的水稻幼苗处理发现, 幼苗植株发病级数为明显下降, 抑制率均38.4%以上, 并且都随着处理浓度提高抑制效果明显提高。本研究结果表明,麦冬块根提取物中含有抑制稻瘟病菌生长的化学物质, 并且能直接抑制稻瘟病菌发生和生长。 相似文献
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Guangjie Liu John L. Bernhardt Melissa H. Jia Yeshi A. Wamishe Yulin Jia 《Euphytica》2008,159(1-2):73-82
Recombinant inbred line (RIL) populations of rice are useful genetic sources for map-based cloning of agronomically important
genes. Zhe733 is a high-yielding indica cultivar from China conferring resistance to rice blast (RB), rice water weevil (RWW) and straighthead; whereas Kaybonnet
low-phytic acid 1-1 (KBNTlpa) is a mutant of a tropical japonica cultivar from the US containing low-phytic acid with average yield, and is susceptible to some RB races, RWW, and straighthead.
A 355 RIL F10−11 population derived from the cross of KBNTlpa × Zhe733 was recently released. Simple sequence repeat (SSR) markers were used to evaluate 269 RILs of this population. A
total of 107 polymorphic markers were mapped on all rice chromosomes representing a total of 1,016.3 cM of genetic distance.
Two hundred and thirty-five KBNTlpa × Zhe733 RILs (KZRILs) were clustered into seven groups based on allele frequencies of SSR markers. Twenty-three markers
(21.1%) on chromosomes 3, 6, 7, 9, and 11 were found to favor Zhe733 (χ
2 = 16.8−189.7 and P < 0.01) and five markers (4.6%) on chromosome 1 and 6 were found to favor KBNTlpa (χ
2 = 18.5−46.6 and P < 0.01). Marker segregations were observed to be normal for both parents except 26 (10.2%) KZRILs were found to skew toward
Zhe733 (χ
2 > 15.7 and P < 0.01). Furthermore, the average frequencies of heterozygosity and non-parental alleles per KZRIL were 1.3% (0.0−38.9%)
and 0.4% (0.0−15.0%), respectively. Thirteen heterozygous KZRILs were found at more than five markers loci and nine KZRILs
were found with more than five non-parental alleles representing 5.1 and 3.5% of 255 KZRILs. Overall, this KZRIL population
is a good population with relatively low frequencies of heterozygosity and non-parental alleles, and with relatively low percentages
of skewed markers and skewed KZRILs. The profiles of these SSR markers should facilitate molecular tagging critical genes
controlling yield, RB, RWW, and straighthead resistance. 相似文献
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Manuel Boissire 《Asia Pacific viewpoint》2002,43(3):293-309
The 1997 El Nio event severely affected the western part of the island of New Guinea. A group of highlands villages at Holuwon experienced drought, forest fires and disruption to food production. This article describes the reaction of the villagers to these natural disasters and to the humanitarian aid that they received. The social order was the first to be affected. Severe competition developed for the allotments of humanitarian aid and yet sharing of land and other help were offered to neighbouring ethnic groups. Reactions were also observed at the level of religion and were manifested in the Yalis search for an explanation of the events. Lastly, there was preservation and reconstruction in the form of the fighting of forest fires and the recreation of gardens following the drought. 相似文献
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Dante L. Adorada B. J. Stodart C. Vera Cruz G. Gregorio I. Pangga G. J. Ash 《Euphytica》2013,192(1):1-16
Sheath lesions, grain sterility and grain discolouration of rice caused by Pseudomonas fuscovaginae can cause yield losses of up to 100 %. The most sustainable method of managing this disease is the use of host plant resistance. To identify sources of resistance an inoculation method that is practical, rapid and reliable is needed. We compare three different inoculation methods. Results showed that the pin-prick method is appropriate for identifying sources of resistance to P. fuscovaginae, while the spray method could be useful for mass screening of rice genotypes. The seed-soaking method was also evaluated and has showed potential in detection of early disease resistance. A total of 16 Multiparent Advanced Generation Inter-Crosses and 20 OryzaSNP set varieties from the International Rice Research Institute were evaluated using the pin-prick and seed-soaking methods. All growth stages were susceptible to the pathogen and the 107 cfu mL?1 inoculum concentration was optimal for discriminating between resistant and susceptible genotypes. For the pin-prick method, a single point assessment of disease severity at 14 days post-inoculation could be used instead of the AUDPC values to classify genotypes. An index of reduction in seedling height 10 days after seed soaking was established for the classification of the genotypes reaction to the disease. Resistant varieties identified using both the pin-prick and seed-soaking methods could be verified for use in disease resistance breeding programs. Of the 36 genotypes evaluated 22 were found to be resistant at the late booting or early panicle exsertion stage by pin-prick method, while 25 were resistant at the seed to germination stage. No correlation was found between the resistance classification of varieties between the two inoculation methods, indicating that there could be different mechanisms of resistance to P. fuscovaginae in rice. 相似文献
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铜浸种对玉米幼苗生长和抗氧化酶的影响 总被引:3,自引:0,他引:3
利用不同浓度的CuSO4.5 H2O对玉米浸种,研究铜(Cu2+)对玉米幼苗生长和抗氧化酶的影响。结果表明:当Cu2+浓度小于10 mg/L时促进幼苗生长,高出这个浓度时则表现出抑制作用;当Cu2+浓度小于10 mg/L时,抗氧化酶SOD,POD和CAT活性及MDA含量下降,高出这个浓度时则相反;随着Cu2+浓度增大,叶片和根系吸收Cu2+逐渐增加。CuSO4.5 H2O胁迫对根的生长和抗氧化系统及Cu2+的积累比茎叶更为敏感。 相似文献
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本文研究哈密瓜自毒作用对幼苗生长和生理生化作用的影响。结果表明:以不同浓度的叶水浸液分别处理时,对幼苗根长和发根数具有抑制作用,随着浓度的增高,抑制作用逐渐增强,和对照相比,在浓度为50/L、90/L时达到显著或极显著水平;而对株高和幼苗鲜重则具有促进作用。经幼苗生理生化测定,叶绿素a、叶绿素b、类胡萝卜素含量随水浸液浓度升高而显著下降;过氧化物酶在水浸液浓度为50g/L时活性最高,之后随水浸液浓度增高而逐渐下降。 相似文献
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水分胁迫对水稻生长发育及产量的影响 总被引:2,自引:2,他引:2
选用抗旱性不同的3个杂交水稻品种,分别在正常供水和水分胁迫条件下,研究水稻产量构成因素及株高、穗长、叶面积、干物质积累等生育特性的变化。结果表明:水分胁迫下,水稻株高降低,叶面积及叶面积指数减小;各器官干物重、总干重均明显降低;前期干物质积累缓慢,后期植株衰老加速。水分胁迫引起各品种穗长、一次枝梗数、二次枝梗数、有效穗数、每穗粒数、结实率、千粒重均下降,最终引起产量降低。品种的抗旱性不同,其产量及其构成对水分胁迫的反应存在一定差异,表现为抗旱性强的品种下降幅度相对较小。 相似文献
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盐分对普通玉米种子发芽和幼苗生长的影响 总被引:1,自引:0,他引:1
选择4种中性盐(NaCl、KCl、Na2SO4和K2SO4)和4种碱性盐(Na2CO3、NaHCO3、K2CO3和KHCO3),设置Ommol/L(对照)、50mmol/L、100mmol/L、150mmol/L和200mmol/L 5个浓度,借助InfoStat软件中DGC方差分析法,分析了盐类型和浓度对普通玉米种子发芽率和幼苗生长的影响.结果表明,盐胁迫延缓了玉米种子的发芽时间,且随着盐浓度增加胁迫作用增强.硫酸盐对幼苗生长的胁迫作用大于氯盐,钠盐大于钾盐,碳酸盐大于硫酸盐,二价盐大于一价盐,碱性盐大于中性盐. 相似文献
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Genetic effects on Fe, Zn, Mn and P contents in Indica black pericarp rice and their genetic correlations with grain characteristics 总被引:2,自引:0,他引:2
Complete diallel crosses with 6 varieties of black pericarp rice and 1 variety of aromatic white rice were conducted to analyze
the seed, maternal and cytoplasmic genetic effects on Fe, Zn, Mn and P contents in kernels by using a genetic model for quantitative
traits of seeds in parents and their F1s and F2s. Seed, maternal as well as cytoplasmic genetic effects controlled the contents of all the mineral elements studied. The
seed genetic effects were found to be more influential than the maternal genetic effects on Fe, Zn, Mn contents. Seed additive
effects constituted a major component of the genetic effects whereas the seed additive along with maternal additive and dominant
effects formed the main part in the inheritance of P content. The heritabilities of seed effects on all the mineral contents
were highly significant (p< 0.01). The estimated values of narrow-sense heritabilites of seed genetic effects on Fe, Zn and Mn contents were high, while
those of seed and maternal effects on P content were intermediate. Single plant selection and single grain selection based
on the seed mineral element contents were advocated to improve the hybrid progeny. Genetic correlations showed that there
existed significant genetic correlations of seed additive, seed dominance, cytoplasm, maternal additive and maternal dominance
between grain characteristics such as 100-grain weight,grain length, grain width, grain shape and mineral elements Fe, Zn,
Mn and P contents. Indirect selection of grain characteristics may be one of the breeding methods to select for higher contents
of Fe, Zn, Mn and P in black pericarp indica rice.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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夏玉米玉米5叶期行间进行机械化深松表明,间隔120cm深松比间隔60cm深松增加株高、茎粗、根层数、茎节数、展开叶数、叶面积指数,降低穗位高。从深松深度看,拔节期深松对植株的生长有一定的抑制效应,尤其是深松20cm,株高降低,茎节数、展开叶、可见叶数及叶面积指数均比对照降低。间隔120cm深松30cm处理可以提高叶面积指数,增加株高、茎节数、茎粗和降低植株的穗位高度,土壤蓄水保墒效果较好,产量和水分利用效率最高分别比对照提高8.86%、6.59%。 相似文献
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为了深入研究生物防治菌棘孢木霉T4菌株小分子疏水蛋白hyb2的功能,基于已知小分子疏水蛋白基因hyb2部分cDNA序列设计引物,分别以棘孢木霉T4菌株菌丝体总mRNA和基因组DNA为模板,进行PCR扩增,克隆获得hyb2的全长cDNA和DNA序列,其GenBank接受号分别为JX014433和JX185070,cDNA序列编码区长度为321 bp,编码106个氨基酸。BlastP相似性分析表明该基因与深绿木霉的Tahyd5a (ABS59366)基因同源性最高为87%,SignalP信号肽分析表明N端第16和17个氨基酸中间有一个信号肽剪切位点(AFA||AP)。Pfam蛋白家族分析表明它属于hydrophobin_2 superfamily家族。将棘孢木霉T4菌株小分子疏水蛋白基因hyb2对深绿木霉ATCC74058基因组和绿色木霉Gv29-8基因组进行同源性搜索,在2个近缘种的基因组上分别获得9个和8个同源序列。其中,深绿木霉ATCC74058的hyb-a-7和绿色木霉Gv29-8的hyb-v-5疏水蛋白与棘孢木霉Hyb2相似性最高分别为87%和70%,2个序列分别位于深绿木霉ATCC74058染色体骨架5和绿色木霉Gv29-8染色体骨架22上。 相似文献
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为了探索包衣尿素养分释放规律和对育苗生长的影响,以普通尿素为对照,分别按等氮量设置了L30、L60和S60三种释放类型树脂包衣尿素处理并进行黄瓜穴盘基质育苗试验。在第15、21、29、36天测定了基质、肥料及幼苗中氮素含量变化情况,并在最后一天还测定了壮苗指数。结果表明:不同处理间基质中无机氮含量、幼苗吸氮量以及壮苗指数差异显著,其中L30处理氮素的释放与黄瓜幼苗吸氮趋势相吻合。幼苗株高、茎粗、单株干物重均优于CK处理,壮苗指数提高20.2%。因此,采用L30型控释氮肥,可以实现一次底肥投入,达到育苗期间免追氮肥的目标。 相似文献