增氧对水稻根系生长与氮代谢的影响

 以国稻6号(杂交籼稻)和秀水09(粳稻)为材料,在水培条件下研究通气增氧对水稻苗期根系生长和氮代谢的影响。结果表明,增氧处理水稻根系干物质积累量、根长、根体积、根系活力以及吸收面积较对照均有不同程度增加。水稻根系硝态氮（NO3 N）含量、游离氨基酸和可溶性糖含量均增加。谷氨酸合成酶（GS）、谷草转氨酶（GOT）和谷丙转氨酶（GPT）活性均增强。在本试验条件下,增氧能显著提高粳稻秀水09苗期根系氮代谢相关酶生理活性;但增氧对杂交籼稻国稻6号根系氮代谢相关酶生理活性影响不显著,说明通气增氧对水稻根系氮代谢生理活性的影响可能与水稻基因型有关。     

高温对水稻灌浆期籽粒氮代谢关键酶活性及蛋白质含量的影响

 选用粳稻品种越光与籼稻品种IR72为材料,研究了高温对水稻灌浆期籽粒谷氨酰胺合成酶（GS）、谷氨酸合酶（GOGAT）、谷氨酸 草酰乙酸转氨酶（GOT）、谷氨酸 丙酮酸转氨酶（GPT）的活性及蛋白质与氨基酸含量的影响。结果表明,灌浆期高温下水稻籽粒GOGAT、GOT与GPT活性显著或极显著升高,但籽粒GS活性显著或极显著降低;籽粒蛋白质及氨基酸各组分含量极显著增加。高温下籽粒GS活性显著降低并未影响籽粒蛋白质的合成,认为籽粒GS不是限制水稻蛋白质合成的关键酶。     

Effects of Rhizosphere Dissolved Oxygen Content and Nitrogen Form on Root Traits and Nitrogen Accumulation in Rice

Dissolved oxygen and nitrogen form have important effects on rice root growth and nitrogen availability.An indica hybrid rice,Guodao 1,and a conventional japonica rice,Xiushui 09,were cultured in hypoxic nutrient solution with NH4NO3 or(NH4)2SO4 as the nitrogen source for six weeks in pools.A portion of the Guodao 1 seedlings after treatment in the pools for four weeks were transferred to a split-root system at different dissolved oxygen contents and cultured for an additional two weeks.Biomass,root morphol...     

根际溶氧量与氮素形态对水稻根系特征及氮素积累的影响

 为研究根际溶氧量和氮素形态对水稻根系生长及对氮素利用的影响,设计了两个试验：1)分别以铵硝混合营养（NH4NO3）和全铵营养[(NH4)2SO4]为氮源,在营养液中将杂交籼稻国稻1号和常规粳稻秀水09培养6周,在第4周和第6周时取样测定植株的生物量和氮素含量;2) 将上述铵硝混合营养下培养4周的国稻1号水稻植株,以分根培养的方式进行不同溶氧量处理,测定水稻生物量、根系形态和氮积累量的差异。结果表明: 1）根际溶氧量较低时(溶氧量0~1.0 mg/L),铵硝混合营养比单一的铵态氮营养显著提高植株的生物量,国稻1号生物量增加69%,秀水09增加41%;铵硝混合营养显著提高了水稻的根系数量、最长根长、根干质量和根系活力以及植株的氮积累量,国稻1号的地下部和地上部氮积累量分别提高60%和52%,秀水09则分别提高了41%和33%。2) 分根实验中,铵硝混合培养的国稻1号,其增氧(溶氧量8.0~9.0 mg/L)处理的根系生物量增加21.6%, 根系数量、最长根长和根体积分别增加27%、14%和10%,而氮积累量提高了11%。增氧和铵硝混合营养均对促进水稻根系生长和氮素积累具有正互作效应。     

花前氮亏缺对水稻叶片氮代谢酶活性的影响

以籼型杂交稻中浙优1号和籼粳型杂交稻甬优12为材料,试验分析了花前不同时期氮亏缺处理对水稻叶片氮代谢酶活性的影响。结果表明,花前氮亏缺导致植株上3叶氮浓度、NR、GS、GOGAT、GOT和GPT酶活性大幅下降,GDH活性显著增长,且各叶位对花前氮亏缺敏感度总体上表现为剑叶倒2叶倒3叶;破口期亏氮对籼型杂交稻中浙优1号上3叶氮同化酶活性的影响远小于减数分裂期处理,与之相比,籼粳杂交稻甬优12对破口期亏氮胁迫仍较敏感,表明中浙优1号植株氮代谢酶的亏氮敏感性由减数分裂期至破口期逐步下降,对土壤速效氮的需求同步降低,甬优12则对土壤供氮存在更高需求。     

灌浆前期高温对小麦籽粒氮代谢关键酶活性的影响

为探讨花后高温胁迫对小麦籽粒氮代谢及蛋白质合成的影响机制,以黄淮地区高产小麦品种郑麦366为材料,利用人工气候室模拟花后高温的方式,在盆栽条件下研究了灌浆前期短暂高温对小麦强势粒和弱势粒谷丙转氨酶(GPT)、谷草转氨酶(GOT)活性的影响.结果表明,灌浆前期高温显著提高了籽粒蛋白质含量,降低了籽粒蛋白质积累量和氮代谢关键酶GPT、GOT活性,其中强势粒GPT活性受高温胁迫的影响较大.小麦籽粒蛋白质含量与GPT和GOT活性均呈负相关,但相关性在不同时期间、强势粒与弱势粒间有差异,强势粒GPT活性与蛋白质含量的关系更密切.     

High Temperature at Grain-filling Stage Affects Nitrogen Metabolism Enzyme Activities in Grains and Grain Nutritional Quality in Rice

Rice plants would more frequently suffer from high temperature (HT) stress at the grain-filling stage in future. A japonica rice variety Koshihikari and an indica rice variety IR72 were used to study the effect of high temperature on dynamic changes of glutamine synthetase (GS) activity, glutamate synthase (GOGAT) activity, glutamic oxalo-acetic transminase (GOT) activity, glutamate pyruvate transminase (GPT) activity in grains and grain nutritional quality at the grain-filling stage. Under HT, the activiti...     

腐植酸浸种对不同耐盐性小麦品种幼苗碳氮代谢的影响

为了解腐植酸对小麦盐胁迫的缓解作用,以春小麦耐盐品种龙麦26和盐敏感品种克旱16为材料,分别用清水和腐植酸浸种,利用水培方式进行幼苗培养,在NaC1胁迫7d后,测定幼苗叶片硝态氮、铵态氮、可溶性蛋白质、蔗糖、可溶性糖含量,以及硝酸还原酶(NR)、谷氨酰胺合成酶(GS)和蔗糖磷酸合成酶(SPS)活性,分析腐植酸与盐胁迫对小麦碳氮代谢的互作效应.结果表明,盐胁迫抑制了春小麦茎叶的生长,降低了幼苗叶片硝态氮、铵态氮、可溶性蛋白质含量,以及NR活性和NR/SPS活性比.盐胁迫后,龙麦26的蔗糖、可溶性糖含量降低,叶片GS活性提高,但克旱16的蔗糖和可溶性糖含量升高.腐植酸浸种降低了盐胁迫下叶片硝态氮含量和NR、GS、SPS活性,提高了铵态氮、蔗糖和总可溶性糖含量,增加了龙麦26的可溶性蛋白质含量和NR/SPS活性比,以及克旱16的SPS活性,而降低了克旱16的可溶性蛋白质含量和NR/SPS活性比及龙麦26的SPS活性.推测腐植酸浸种可能是通过调控SPS活性和降低NR活性来增加蔗糖含量,从而影响小麦在盐胁迫下的碳氮代谢及平衡.     

抗草潜力不同的水稻品种混合种植对稗草的抑制作用

以秀水63（化感指数为0.24,竞争力弱）、PI312777（化感指数为0.61,竞争力强）、国稻1号（化感指数为0.55,竞争力强）为材料,采用盆栽试验和田间试验相结合的方法,研究了抗草潜力不同的水稻品种混种对稗草萌发和生长的影响。盆栽试验结果表明,PI312777和国稻1号对稗草萌发抑制作用显著,而秀水63对稗草萌发无抑制作用;秀水63与PI312777或国稻1号混合种植后,稗草的萌发均受到抑制。盆栽和田间试验均表明,在单种情况下,稗草的生物量在PI312777和国稻1号的试验小区均低于秀水63的试验小区。秀水63与PI312777、秀水63与国稻1号混合种植,稗草的生物量均显著降低。与抗草潜力高的水稻品种（PI312777和国稻1号）混合种植,在一定程度上能增强秀水63对稗草的抑制能力。     

增氧灌溉对水稻生理特性和后期衰老的影响

以常规粳稻秀水09、杂交籼稻国稻6号和两优培九为试材,于2007-2008年采用大田试验,研究了增氧灌溉对水稻生理特性和后期衰老的影响。结果表明,与常规灌溉水相比,超微气泡水的溶氧量明显提高而且下降速率慢。增氧灌溉处理土壤氧化还原电位显著或极显著提高,有效穗数、结实率和产量显著提高。进一步分析表明,增氧灌溉处理下秀水09和两优培九叶片光合速率分别较对照提高了4.13%和3.78%;而且增氧灌溉显著提高叶片叶绿素和可溶性蛋白质含量,气孔导度也有较大的增加;此外,增氧灌溉处理还增强了水稻生育后期的根系功能,提高了叶片超氧化物歧化酶活性,降低了叶片丙二醛含量,延缓叶片衰老,延长了叶片功能期从而促进籽粒灌浆结实。     

Effect of exposure to a country liquor (Toddy) during gestation on lipid metabolism in rats

The objective of this study was to determine theeffects of country liquor Toddy and its equivalentquantity of ethanol on lipid metabolism duringgestation in rats. Female rats weighing an average of125 g were exposed to Toddy (24.5 ml/body weight/day)and ethanol (0.52 ml/kg body weight/day) for 15 daysbefore conception and throughout gestation. On the19th day of gestation, altered liver function andhyperlipidemia was seen in both the treated groups.Altered liver function was evidenced by the increasedactivity of alcohol dehydrogenase, aldehydedehydrogenase, glutamic oxaloacetic transaminase oraspartate amino transferase (GOT), glutamic pyruvictransaminase or alanine amino transferase (GPT) andgamma glutamyl transpeptidase (GGT). Hyperlipidemiawas caused by increased biosynthesis and decreaseddegradation of lipids. The incorporation of ¹⁴Cacetate in lipids and activities of HMG CoA reductaseand lipogenic enzymes were elevated and activity ofLPL and bile acids contents were decreased. Toddytreated rats were more severely affected than thosereceiving an equivalent quantity of ethanol. Toddyseemed to potentiate the toxicity induced by alcoholindicating the role of the nonethanolic portion.Hepatic functions were also affected.     

Effects of Aerated Irrigation on Leaf Senescence at Late Growth Stage and Grain Yield of Rice

With the japonica inbred cultivar Xiushui 09,indica hybrid combinations Guodao 6 and Liangyoupeijiu as materials,field experiments were conducted in 2007 and 2008 to study the effects of aerated irrigation on leaf senescence at late growth stage and grain yield of rice.The dissolved oxygen concentration of aerated water evidently increased and decreased at a slow rate.The soil oxidation-reduction potential under aerated irrigation treatment was significantly higher than that of the CK,contributing to significant increases in effective panicles,seed setting rate and grain yield.In addition,the aerated irrigation improved root function,increased superoxide dismutase activity and decreased malondialdehyde content in flag leaves at post-flowering,which delayed leaf senescence process,prolonged leaf functional activity and led to enhanced grain filling.     

Transgene Flow from Glufosinate-Resistant Rice to Improved and Weedy Rice in China

The development of transgenic rice with novel traits in China can increase rice productivity, but transgene flow to improved or weedy rice has become a major concern. We aimed to evaluate the potential maximum frequencies of transgene flow from glufosinate-resistant rice to improved rice cultivars and weedy rice. Treatments were arranged in randomized complete blocks with three replicates. Experiments were conducted between 2009 and 2010 at the Center for Environmental Safety Supervision and Inspection for Genetically Modified Plants, China National Rice Research Institute, Hangzhou, China. Glufosinate-resistant japonica rice 99-1 was the pollen donor. The pollen recipients were two inbred japonica rice （Chunjiang 016 and Xiushui 09）, two inbred indica rice （Zhongzu 14 and Zhongzao 22）, two indica hybrid rice （Zhongzheyou 1 and Guodao 1）, and one weedy indica rice （Taizhou weedy rice）. The offspring of recipients were planted in the field and sprayed with a commercial dose of glufosinate. Leaf tissues of survivors were analyzed by polymerase chain reaction to detect the presence of the transgene. The frequency of gene flow ranged from 0 to 0.488%. In 2009, the order of gene flow frequency was as follows： weedy rice 〉 Chunjiang 016 〉 Xiushui 09 and Zhongzu 14 〉 Guodao 1, Zhongzheyou 1 and Zhongzao 22. Gene flow frequencies were generally higher in 2009 than in 2010, but did not differ significantly among rice materials. Gene flow frequency was the highest in weedy rice followed by the inbred japonica rice. The risk of gene flow differed significantly between years and year-to-year variance could mask risk differences among pollen recipients. Gene flow was generally lesser in taller pollen recipients than in shorter ones, but plant height only accounted for about 30% of variation in gene flow. When flowering synchrony was maximized, as in this study, low frequencies of gene flow occurred from herbicide-resistant japonica rice to other cultivars and weedy rice. Averaged across years, the risk     

镉胁迫对不同水稻品种种子萌发、幼苗生长和淀粉酶活性的

以镉耐性不同的两个水稻品种秀水110(耐镉型)和秀水11(镉敏感型)的种子为材料,采用室内培养方法,研究了水稻种子萌发、幼苗生长和淀粉酶活性对Cd胁迫的响应。结果表明,在水稻种子萌发过程中,胚根和胚芽对Cd要比种子本身敏感,而胚根较胚芽更敏感。 Cd胁迫能显著影响发芽指数、活力指数、根长、淀粉酶活性,其中对秀水11的影响更明显;在高于5 μmol/L Cd浓度下,秀水11植株内的Cd含量明显高于秀水110,造成后者根尖有丝分裂指数和淀粉酶活性明显降低,受到的毒害更严重。     

灌溉方式和施氮量对冬小麦籽粒氮代谢酶和蛋白质产量的影响

为探究不同灌溉方式和施氮量对冬小麦籽粒氮代谢酶活性及蛋白质产量的影响,以矮抗58为材料,分析了不同灌溉方式（滴灌和漫灌）和施氮量下小麦籽粒产量、蛋白质产量及灌浆期不同穗位籽粒谷丙转氨酶（GPT）和谷氨酰胺合成酶（GS）活性的变化。结果表明,与漫灌相比,滴灌处理可显著提高籽粒产量和蛋白质产量,施氮量220 kg·hm^-2下籽粒产量和蛋白质产量最高;各水氮处理下,小麦不同穗位籽粒GS和GPT活性均随籽粒灌浆进程的推进而降低,花后7～14 d下降迅速,之后下降缓慢;滴灌下,增施氮肥可显著提高灌浆中期中部和下部穗位籽粒GS活性及整个灌浆期各穗位籽粒GPT活性;漫灌下,增施氮肥可显著提高整个灌浆期中部和下部穗位籽粒GS活性及各穗位籽粒GPT活性。相关性分析表明,成熟期籽粒蛋白质含量分别与下部穗位籽粒GS活性、中部和下部穗位籽粒GPT活性呈显著相关,蛋白质产量分别与下部穗位籽粒GS活性和上部穗位籽粒GPT活性呈显著相关,籽粒产量与下部穗位籽粒GS活性及各穗位GPT活性呈显著相关。综合考虑籽粒产量、蛋白质产量及水氮投入认为,滴灌下施氮量220 kg·hm^-2可作为该地区小麦适宜栽培模式的参考。     

Effects of Cadmium Stress on Seed Germination, Seedling Growth and Seed Amylase Activities in Rice (Oryza sativa)

Two rice varieties, Xiushui 110 with high cadmium (Cd) tolerance and Xiushui 11 with low Cd tolerance were used to study the effects of Cd stress on seed germination, seedling growth and amylase activities. The low cadmium concentration had little effect on seed germination rate. However, cadmium stress could significantly inhibit plumule and radicle growth, especially for radicle growth. Germination index, vigour index, radicle length and amylase activities of Xiushui 11 decreased more significantly with the increasing cadmium level compared with Xiushui 110. The cadmium content in seedlings of Xiushui 11 was higher than that in Xiushui 110 when the cadmium concentration exceeded 5 μmol/L, which caused lower mitotic index in root tips and amylase activities, and more serious cadmium toxicity in Xiushui 11.     

芸薹素内酯对稻草基质育秧水稻秧苗生理特性及栽后生长的影响

【目的】筛选出机插水稻基质育秧芸薹素内酯(BR)适宜的施用方法及最佳用量。【方法】以中早39为供试材料,采用稻草基质旱育秧方式,探究BR不同处理方式和浓度对机插早稻秧苗生理特性及栽后生长的影响。【结果】施用BR可以提高秧苗的抗氧化保护酶活性,降低丙二醛含量,增加可溶性蛋白含量、总糖含量及C/N,秧苗根系活力提高了13.24%~48.31%,利于形成抗性强的健壮秧苗;喷施方式对提高秧苗超氧化物歧化酶、过氧化物酶、过氧化氢酶活性效果最佳,基施方式对降低秧苗丙二醛含量效果最好。施用适量BR也可促进秧苗机插后长出新叶、新根及返青,喷施方式效果最好;浸种、喷施方式还能增强秧苗机插后20~30 d的单株分蘖力。【结论】播种前和出苗后进行两次适量的BR处理,有利形成壮苗和栽后活棵返青及分蘖,以播前0.15 mg/L浸种和秧苗1叶1心期0.10 mg/L喷施效果为好。     

Effect of in utero exposure of Toddy (coconut palm wine) on liver function and lipid metabolism in rat fetuses

The objective of this study was to determine the effects of a country liquor Toddy (Coconut palm wine) and an equivalent quantity of ethanol on liver function and lipid metabolism in utero. Female albino rats with an average weight of 125± 5 g were exposed to Toddy from coconut palm (24.5 ml/kg-1 body weight/day) and ethanol (0.52 ml/kg body weight/day) for 15 days before conception and during pregnancy. On day 13 and day 19 of gestation, altered liver function and hyperlipidemia were seen in the fetuses of both the treated groups. Altered liver function was evidenced by the increased activity of alcohol dehydrogenase, aldehyde dehydrogenase, glutamic oxaloacetic transaminase (aspartate amino transferase (GOT)), glutamic pyruvic transaminase (alanine amino transferase (GPT)). Hyperlipidemia was caused by increased biosynthesis since the incorporation of 14C acetate into lipids and activities of HMG CoA reductase and lipogenic enzymes were elevated. Toddy treated fetuses were more severely affected than those exposed to an equivalent quantity of ethanol. Toddy seemed to potentiate the toxicity induced by alcohol suggesting the role of non alcoholic components. Hepatic functions of the day 13 fetuses were effected to a lesser degree than those in the day 19 hepatic liver.     

不同属性特征基质对早稻秧苗耐低温的影响

【目的】早稻育秧过程中易遭受低温冷害,引起水稻减产。因此,有必要研究不同类型的基质对早稻秧苗耐低温的影响。【方法】以水稻田自然表层土为对照,采用两种代表性基质(无土基质和发酵基质)培育早稻秧苗,在水稻出芽6 d后进行不同低温处理,3 d后测定水稻的基本理化性质指标和基因表达,明确不同基质对早稻秧苗耐低温胁迫的调节作用。【结果】1）无土基质和发酵基质容重均显著低于对照,电导率、通气孔隙、碱解氮、速效磷、速效钾和有机质含量显著高于对照;发酵基质育成的秧苗其根长、百株地上部干质量和百株根部干质量均显著高于对照,无土基质和发酵基质育成的秧苗根系和地上部的氮、磷、钾养分含量显著高于对照。2）随着温度的降低,水稻秧苗的生长和养分吸收均受到抑制。低温对发酵基质上生长的秧苗抑制作用较弱,无土基质次之,对照受抑制较强。3）在低温条件下(白天8℃/晚上4℃),无土基质和发酵基质中育成的秧苗丙二醛含量显著低于对照,说明在寒冷条件下的细胞氧化损伤较少。其中,无土基质和发酵基质育成的秧苗超氧化物歧化酶、过氧化氢酶活性,脯氨酸含量和可溶性蛋白含量均高于对照,发酵基质育成的秧苗过氧化物酶活性高于对照,无土基质育成的秧苗谷胱甘肽转移酶活性高于对照。同时,无土基质和发酵基质育成的秧苗OsCold1、OsCOIN、OsP5CS和OsSODB四个基因表达水平均显著高于对照,提高了水稻耐低温能力。【结论】以上结果表明,无土基质和发酵基质通过调控水稻秧苗的生理生化反应和相关基因表达,提高秧苗耐低温胁迫能力。     

环剥对毛叶枣叶片N同化能力和糖积累的影响

对当年春季抽生的毛叶枣(Indian jujube)枝条进行环剥,并以不环剥的枝条为对照,探讨环剥对毛叶枣叶片氮(N)同化能力和糖积累的影响.结果表明,环剥后能降低叶片硝酸还原酶(NR)、谷氨酰胺合成酶(GS)、谷氨酸合成酶(GOGAT)的活性,导致叶片总N含量降低;环剥使叶片可溶性总糖、蔗糖和淀粉含量增加.