氧化硫硫杆菌对水稻旱育苗床土壤调酸效果研究初报

利用硫磺粉以及土壤中的元素硫或硫的其它不完全氧化物在微生物氧化硫硫杆菌的作用下进行氧化生成硫酸,使水稻旱育苗床土壤pH=4.5—5.2之间。培育健壮秧苗,消除病虫害。试验结果表明,秧苗株高增长率是对照处理的64％,干物质积累比对照处理增加30％。     

中国裸燕麦β-葡聚糖含量的鉴定研究

对来源于中国13个省（区）1010份和国外引进的4份裸燕麦品种（系）进行了β-葡聚糖含量的鉴定研究。结果表明,中国裸燕麦β-葡聚糖含量为2．0％～7．5％,其中含量〈3．00％的占6．61％,3．00％～4．99％的占86．4％。5．00％～5．99％的占5．72％,≥6．00％的占1．18％。按品种类型划分,地方品种的含量低于育成品种（系）。按来源地划分,河北、山西、内蒙古的含量较高,云南、贵州、四川的含量较低,而陕西的含量最低。同年不同地点或相同地点不同年份种植的相同品种（系）,含量有一定的变化（0．27％～0．83％）。在鉴定中筛选出一批高β-葡聚糖品种（系）。本研究不仅为燕麦高β-葡聚糖育种提供了理论依据和物质基础,而且为降脂燕麦保健片的生产提供了优良品种。     

早晚季水稻精米和米皮硒含量的基因型差异研究

选用福建省生产上推广应用的水稻品种(组合)、特种稻和旱稻共45份种质资源为试验材料,在早、晚季分析不同基因型水稻精米和米皮中硒含量的差异.结果表明:①早、晚季水稻品种精米和米皮中硒含量表现均无明显差异.②水稻品种精米和米皮中硒含量分布遵循正态分布规律,表明水稻精米和米皮中硒含量属数量性状.③不同基因型水稻品种精米和米皮中硒含量差异很大,不同品种具有不同的富硒能力.其中早季精米硒含量最高的品种是罗旱紫谷(0.065mg/kg),最低的是84VE303(0.012mg/kg);晚季精米硒含量最高的品种是罗旱紫谷(0.068mg/kg),最低的是加州红米(0.009mg/kg).④早、晚季种植的精米硒含量达0.04 mg/kg以上的水稻品种有:罗旱紫谷、隆化大红欲、555-99、Ziukdo、矮血糯,其中罗旱紫谷精米中硒含量最高,早晚季平均达0.067 mg/kg.     

高寒地区四倍体刺槐引种栽培试验

通过对四倍体刺槐进行引种栽培试验。结果表明：(1)四倍体刺槐苗在高寒地区引种栽培。平均成活率达85％以上;(2)1年生四倍体刺槐比2年生苗的适应能力强,移栽成活率为95％以上;(3)1年生苗的萌芽期、晨叶期比2年生苗平均早6～9d;(4)该树种可适应西藏地区特殊的高寒气候紊件。且生长旺盛。枝叶繁茂。成活率高．有较强的开发潜力。     

UV-B辐射增强对水稻多胺代谢及内源激素含量的影响

研究表明,在处理前期（7－14d),增强的UV－B辐射能使供试水稻汕成63（Sy63）的精氨酸脱羧酶（ADC）、鸟氨酸脱羧酶（ODC）和s－腺苷蛋氨酸脱羧酶（SAMDC）活性分别平均增加165．74％、104．60％和89．60％,南川（NC）的这3种酶活性分别增加59．91％、41．30％和23．68％,IR65600－85只表现出ADC和ODC活性分别平均提高115．93％、14．45％,SAMDC活性却下降33．01％,在处理后期（21－28d）,Sy63的ADC－ODC活性分别对照平均增加89．72％、3．71％,NC则分别增加73．95％、27．38％,IR656000－85表现为ADC活性增加94．41％,ODC活性却下降13．57％,就SAMDC而言,处理后期（21－28d）,三者分别下降40．06％、19．20％和38．21％,多胺氧化酶（PAO）活性变化趋势恰好相反,从而引起多胺（PA）含量特别是腐胺（Put）含量明显上升,此外,UV－B辐射增强能使IAA和GA11／3含量在整个处理期间（7－28d）供试水稻品种（组合）Sy63分别平均下降58．92％和45．48％,NC分别减少43．31％和56．20％,IR65600－85则分别降低38．69％和47．33％,所有供试水稻品种（组合）的ZRs含量表现为处理前期（7－14d）有所降低,处理后期（21－28d）则明显提高,就ABA含量而言,整个处理时间（7－28d）,3个品种（组合）均比对照显著或后期（21－28d）则明显提高,就ABA含量而言,整个处理期间（7－28 d）,3个品种（组合）均比对照显著或极显著增加,三者分别提高了14．4%、99．6％和56．7％,从而显著降低IAA／ABA、GA1／3／ABA和ZRs/ABA的比值,影响水稻生长发育。     

阿月浑子栽培品种生长及结实生物学特性研究

对来自美国和新疆的6个阿月浑子(Pistacia vera L．)品种的生长及结实生物学特性进行了研究。分析结果表明：Kerman和26—18^#品种嫁接后3年开花结实。品种与50年生黄连木亲和力较高,嫁接成活侏率和成活穗率达70％～100％,但品种在5月20日后有“回芽”现象。枝叶生长呈S型曲线,叶面积指数(LAI)平均达3．98。Kerman品种每个接穗3年后产果穗最高达31个,坚果和核仁发育正常,每个果穗上具坚果88．5～116个。单果重0．81～1．89g,出核率和出仁率分别为54．32％～55．0％和48．08％～59．09％。     

水稻黄绿叶基因的克隆及应用

进一步提高水稻产量，最大限度满足国家对食物安全的需求是水稻遗传育种的重大任务。水稻干物质产量的90％-95％来自光合作用。目前高产水稻光能利用率也仅1．5％-2．0％。理论上，植物光能利用率可达13．0％-14．0％，水稻理想的光能利用率应达3．0％-5．0％。因此，培育高光效的超高产品种是提高产量的主要途径之一。长期以来，水稻光合作用的相关研究大多停留在生理水平上，同时，传统的杂交育种手段在改良水稻光能利用方面至今尚未取得令人满意的结果，而叶色突变体是开展光合作用研究的理想材料。     

布氏白僵菌菌丝制剂的贮存活力

本试验制备了布氏白僵菌（Beauveriabrongniartii）9405的几种菌丝颗粒剂和粉剂,并测定其贮存活力。当贮存6个月时,在4℃和室温贮存的藻胶颗粒剂的存活率比贮存1个月时分别下降了31．4％～76．8％和76．0％～92．6％。4个粉剂中,7号和10号在4℃的存活率比贮存1个月分别下降11.0％和8．5％,而其它两个的存活率却略有增加;在室温贮存的存活率下降8．2％～33．1％。颗粒剂在土壤中有一个恢复生长过程,然后逐渐衰落。     

水稻国外引种的探讨和建议

自1949年以来,中国共引进国外普通栽培稻品种(系)23890份和野生稻种质资源2201份,这些资源中许多已被直接或间接用于生产或育种.其中,年种植面积超过6.67万公顷的品种23个,年种植面积0.667～6.67万公顷的品种75个;直接利用于杂交水稻的国外恢复系或利用国外强恢复源培育的恢复系,已占我国恢复系总数的95.7%;众多国外品种成为我国高产、优质和多抗育种的骨干亲本.因此,加强国外水稻资源的引入、评价和利用,对于丰富我国稻种资源宝库和增加遗传多样性意义重大,也是应对各国激烈争夺生物资源的战略决策.本文根据水稻国外引种出现的新情况,重点阐述了我国的引种规律、引种地区和强化引种的建议.     

响应面法优化毛霉菌发酵培养基

采用响应面分析方法优化毛霉菌B的发酵培养基,首先通过单因素试验筛选出葡萄糖为最适碳源,酵母膏和玉米浆为最适氮源,用Plackett—Burman试验对葡萄糖、酵母膏、玉米浆、MgSO4、FeSO4、NILCl/、HPO4进行评估并筛选出具有显著效应的3个因素：葡萄糖、酵母膏、玉米浆,再通过最陡爬坡试验逼近其最大响应区域,最后采用Box—Behnken试验对其用量进行优化,得到毛霉菌最佳发酵培养基（g/L）：葡萄糖51．54,酵母膏5．22,玉米浆14．31,MgSO40．5,FeSO40．1,NH4Cl3,k2HPO43,pH6．0～6．5。培养基优化后,毛霉生物量由23．51g／L提高至31．13g/L,比对照组提高32．41％,腺嘌呤转化率由53．59％提高至59．97％,ATP产率由6．56g／L提高至7．34g／L,比对照组提高11．89％。     

不同水分管理方式下水稻的水分利用效率与产量

采用温室微区试验研究常规水作、裸地旱作、覆膜旱作和覆草旱作等土壤水分管理下水稻生长及其对水分的利用状况。结果表明,几种旱作水稻的需水量为349-473mm,常规水和水稻需水量为762.5mm。旱作水稻的水分籽粒和干物质生产效率为0.899-1.273g·kg^-1和1.655-2.321g·kg^-1之间,而相同条件下常规水作水稻水分的籽粒和干物质生产效率为0.766g·kg^-1和1.459g·kg^-1左右。覆草旱作水稻可以获得相当于常规水作水稻90％的经济产量。     

长期垄作稻田腐殖质稳定碳同位素丰度(δ13C)分布特征

研究了四川盆地丘陵区连续16年垄（宽垄）作稻田土壤稳定碳库腐殖质组分的稳定碳同位素(δ¹³C)分布特征.结果表明： 稻田土壤有机碳含量为宽垄作＞垄作＞水旱轮作.腐殖质碳以胡敏素为主,占土壤碳含量的21%～30%,提取碳以胡敏酸为主,分别占土壤有机碳和腐殖质的17%～21%和38%～65%.土壤有机碳的δ¹³C值介于-27.9‰～-25.6‰,20～40 cm和0～5 cm土壤有机碳δ¹³C值之差约为1.9‰.土壤胡敏酸δ¹³C值比土壤有机碳低1‰～2‰,更接近于油菜和水稻秸秆及根系的δ¹³C值.土壤富里酸δ¹³C值分别较土壤有机碳和胡敏酸高2‰和4‰.耕作层和犁底层胡敏素δ¹³C值分别介于-23.7‰～-24.9‰和-22.6‰～-24.2‰,δ¹³C值的变化反映了耕层中腐殖质的新老混合现象.各有机组分δ¹³C值递减顺序为：胡敏素＞富里酸＞土壤有机碳＞稻草（油菜）残体＞胡敏酸.长期水稻种植有利于增加土壤有机碳含量,同时,耕作方式影响土壤腐殖质δ¹³C在耕作层和犁底层中的分布格局.     

Host response of rice genotypes to the rice root-knot nematode (Meloidogyne graminicola) under aerobic soil conditions

Aerobic rice is a production system where adapted rice varieties are established via direct seeding in non-puddled, non-flooded, non-saturated fields and grown under conditions similar to upland conditions. On land cultivated continuously with aerobic rice, a yield reduction has been observed. The rice root-knot nematode Meloidogyne graminicola is considered one of the possible causes of these yield reductions. Resistance to and tolerance for M. graminicola are essential traits for aerobic rice cultivars in alleviating this problem. In our study, the host response of nineteen aerobic, seven upland and four lowland rice genotypes which are either being used in the International Rice Research Institute’s aerobic rice breeding programme or already cultivated by farmers in Asia was evaluated under aerobic soil conditions in an outdoor raised-bed experiment. Our study showed a large variation in susceptibility and sensitivity to M. graminicola infection among the rice genotypes examined. Resistance comparable to the resistant reference genotypes included in the experiment (CG14, TOG5674, TOG7235) was not found but in terms of susceptibility, the upland genotype Morobereken may be an interesting less-susceptible genotype. Tolerance was found and in terms of sensitivity, the high yielding aerobic genotype IR78877-208-B-1-2 may be an interesting tolerant genotype. Our study also allowed the identification of rice genotypes that are either highly susceptible or sensitive to M. graminicola infection and of which the cultivation should be discouraged. On average, M. graminicola caused an almost 30% reduction in yield. Excluding the two susceptible and three resistant reference genotypes included in the experiment, most affected was dry-shoot biomass (23.6% reduction) followed by root length, which was more affected than fresh-root weight (19.8 vs. 8%) and grain filling (17.3%), while plant height and the number of spikelets/panicle were less affected (10.2 and 8.1%, respectively). Neither tillering nor the number of panicles/plant were affected.     

Genotypic Variation in Root Growth Angle in Rice (Oryza sativa L.) and its Association with Deep Root Development in Upland Fields with Different Water Regimes

Deep root development, which is important for the drought resistance in rice (Oryza sativa L.), is a complex trait combining various root morphologies. The objective of this study was to elucidate genotypic variation in deep root development in relation to morphological indicators such as vertical root distribution and root growth angle. Two experiments were conducted: one on upland fields, and one in pots and fields. In experiment 1, the root systems of six rice cultivars on upland fields were physio-morphologically analyzed under different water regimes (irrigated and intermittent drought conditions during panicle development). In experiment 2, cultivar differences in root growth angles were evaluated with 12 cultivars using the basket method under irrigated conditions. No cultivar × environment interactions were found for total root length or deep root length between irrigated and drought conditions in experiment 1. This suggests that constitutive root growth, which is genetically determined, is important for deep root development under intermittent drought conditions during reproductive stage. Among root traits, the deep root ratio (i.e., deep root weight divided by total root weight) was most closely related to deep root length under both water regimes. This suggested that vertical root distribution constitutively affects deep root length. Significant genotypic variation existed in the nodal root diameter and root growth angle of upland rice in experiment 2. It was considered that genotypes with thick roots allocated more assimilates to deep roots through root growth angles higher to the horizontal plane on upland fields. This is the first report on genotypic variation in the root growth angle of rice on upland fields. It should prove useful for rough estimations of genotypic variation in the vertical root distribution of upland rice because root growth angle is rapidly and easily measured.     

桂西北喀斯特移民区土地利用方式对土壤养分的影响

利用典型喀斯特峰丛洼地主要土地利用方式（灌草地、次生林地、果园、牧草地、旱地）的土壤养分测定数据,研究土地利用变化对土壤养分的影响.结果表明：土壤有机碳、全氮、有效氮含量随土地利用强度的增加而降低,灌草地和次生林地比果园、牧草地和旱地土壤有机质含量高86%～155%、全氮含量高62%～119%、有效氮含量高66%～215%（P<0.05）;全磷和全钾含量主要受养分来源的影响,受土地利用方式影响较小;速效磷含量主要受施肥的影响,有效钾含量则主要受植被覆盖和水土流失状况的影响.土地利用方式是影响土壤有机碳、全氮、有效氮、有效磷、有效钾等养分含量变化的重要因素.粗放的农业耕作降低了土壤养分并引起土壤退化,而植被恢复等措施可以培肥土壤.因此,喀斯特区域应改变粗放的农业耕作方式,加强施用有机肥和平衡施肥,对坡度≥25°的坡耕地采取“退耕还林还草”措施,以恢复和重建喀斯特地区生态环境,实现土地资源的可持续利用.     

糜子抗旱节水相关基因PmMYB的克隆及表达分析

根据在糜子抗旱节水分子基础研究中获得的一个糜子MYB基因的EST序列, 以其序列及水稻MYB18基因的序列为基础设计引物, 扩增得到1 739 bp的全长基因组序列。序列分析表明, 其包含121 bp(347~467 bp)和93 bp(599~691 bp)的两个内含子, 3个外显子; 全长cDNA序列为1 525 bp, 其中3′非翻译区为212 bp, 5′非翻译区为41 bp, 编码区为1 272 bp, 共编码424个氨基酸, C-端存在一个丝氨酸(Ser, S)丰富区。该基因具有两个典型的MYB类转录因子基因的DNA结合区(DNA-binding domain), 分别为13~63、66~114位氨基酸, 属于典型的R2R3-MYB转录因子。对其与水稻、玉米、火炬松、拟南芥、辣椒、陆地棉、大麦及茄子等9种植物的MYB基因的R2、R3重复区的氨基酸序列多重比较, 表明R2R3重复序列在植物中具有较高的保守性; 基于氨基酸序列的编码区系统进化树分析表明, 不同植物的MYB基因遗传分化很大, 序列相似性为32%~84%, 其中糜子MYB基因与水稻的MYB18相似程度最高(84%), 与大麦和玉米的相似性分别为46%和41%。通过半定量RT-PCR对其表达模式分析表明, 该基因在水分胁迫和干旱后复水条件下上调表达, 与糜子抗旱节水紧密相关。该基因的克隆为进一步探讨利用该基因改良其他植物的抗旱节水性奠定了良好的基础。     

Diversity in the Content of Some Nutritional Components in Husked Seeds of Three Wild Rice Species and Rice Varieties in Yunnan Province of China

In addition to rice (Oryza sativa L.) cultivars, there are three wild rice species, namely O.rufipogon Griff, O. officinalis Wall and O. granulata Baill, in Yunnan Province, China. Each species has different subtypes and ecological distributions. Yunnan wild rice species are excellent genetic resources for developing new rice cultivars. The nutritional components of the husked seeds of wild rice have not been investigated thus far. Herein, we report on the contents of total protein, starch, amylose, 17 amino acids, and five macro and five trace mineral elements in husked seeds from three wild rice species and six O. sativa cultivars. The mean (± SD) protein content in the husked rice of O. rufipogon, O. officinalis, and O. granulata was (14.5 ± 0.6)%, (16.3 ± 1. 1)%, and (15.3 ± 0.5)%, respectively. O. officinalis Ⅲ originating from Gengma had the highest protein content (19.3%). In contrast, the average protein content of six O. sativa cultivars was only 9.15%. The total content of 17 amino acids of three wild rice species was 30%-50% higher than that of the six cultivars. Tyrosine, lysine, and valine content in the three wild rice species was 34%-209% higher than that of the cultivars. However, the difference in total starch content among different O. sativa varieties or types of wild rice species was very small. The average amylose content of O. rufipogon, O. officinalis,and O. granulata was 12.0%, 9.7%, and 11.3%, respectively, much lower than that of the indica and japonica varieties (14.37%-17.17%) but much higher than that of the glutinous rice cultivars (3.89%). The sulfur, phosphorus, magnesium, zinc, and ferrite content in the three wild rice species was 30%-158% higher than that of the six cultivars. The considerable difference in some nutritional components among wild rice species and O. sativa cultivars represents a wide biodiversity of Yunnan Oryza species. Based on the results of the present study, it is predicted that some good genetic traits, especially high protein and ideal amylose content, of Yunnan wild rice species may be useful in improving the nutritional value of rice. This is the first report regarding the amino acid, mineral element, protein and amylose content of husked seeds of some Yunnan wild rice species that have important genetic characteristics for rice quality and nutritional value.     

Comparison on physiological adaptation and phosphorus use efficiency of upland rice and lowland rice under alternate wetting and drying irrigation

As one of the most widely promoted water-saving irrigation strategies for rice, alternate wetting and drying irrigation (AWD) can not only save water but also increase mineral nutrient use efficiency. In this study, we compared the growth conditions of four rice varieties (two lowland and two upland varieties) under three irrigation regimes: continuously flooded (CF), alternate wetting and moderate soil drying (AWD15) and alternate wetting and severe soil drying (AWD30). AWD15 and AWD30 enabled the plants to receive fewer irrigation events and less irrigation water than CF, thereby saving both water resources and labor. AWD15 reduced redundant vegetative growth, promoted root growth, and increased the root-shoot ratio and harvest index. AWD15 increased the grain yield, water use efficiency (WUE) and phosphorus use efficiency (PUE) of upland rice and maintained the grain yield while increasing the WUE and PUE of lowland rice. More developed root systems under AWD helped upland rice to maintain a higher water status than lowland rice when plants were subjected to soil drying, which resulted in superior performance in grain yield in upland rice. AWD30 could not reconcile the demands of higher yield and the desire to reduce irrigation water use because it decreased grain yield. The results indicate that AWD15 irrigation of rice can not only increase rice yield and WUE but also enhance PUE, which can potentially reduce the use of phosphorus fertilizers. The results provide theoretical and technical support for improving rice cultivation.     

水、旱条件下稻米蒸煮和营养品质性状与土壤水分环境互作分析及其QTL定位

以旱稻品种IRAT109与水稻品种越富杂交构建的DH群体的116个株系及其亲本为材料,在水、旱2种栽培条件下种植,研究了稻米蒸煮和营养品质性状的变化规律,在水、旱2个土壤水分环境下对直链淀粉含量(AC)、胶稠度(GC)、碱消值(GT)和蛋白质含量(PC)4个蒸煮和营养品质性状进行QTL定位及QTLs与环境互作分析。结果表明,以上4个品质性状在水、旱2种不同栽培条件下差异较大,说明这些性状受水分条件影响较大,旱栽条件下稻米蒸煮和营养各品质性状均有不同程度的升高,其中蛋白质含量平均提高37.9%。QTL分析结果表明,4个稻米品质性状在2个环境中的表现型值都为连续分布,均存在超亲遗传类型,共检测到7个加性效应QTL与稻米蒸煮和营养品质性状4项指标有关,分别位于第1、2、3、6、8、11染色体上,单个QTLs对性状的贡献率在1.91%～19.77%之间。位于第3染色体上控制碱消值的QGt3,第6染色体上控制直链淀粉含量的QAc6,在2个不同土壤水分条件下均与环境存在显著互作,对环境互作的贡献率分别为8.99%和47.86%。控制直链淀粉含量的2对上位性QTLs与土壤水分环境显著互作,贡献率较大,分别为32.54%和11.82%。并筛选到5个主效QTL(QGt6b、QGt8、QGt11、QGc1和QPc2)在抗旱育种中可用于蒸煮和营养各品质性状MAS改良。     

辽宁章古台樟子松人工林水分动态的研究

 本文根据1979—1985年的观测资料,对辽宁省彰武县章古台沙地樟子松人工林水分因子的分布与变化规律及其数量关系进行了分析。结果表明,樟子松人工固沙林的土壤含水率逐渐降低,25年生林分比无林对照区低1.08%。樟子松的蒸腾耗水量占同期降水量的34.7一71.4%,占林地水分输出总量的60.8—71.7%,是水分输出的主要途径,也是发生水分亏缺的主要因素。林分进行适当的疏伐和中耕,对改善水分状况,调整水分关系起一定作用。试验的结果还表明,章古台地区干旱年的降水量大致相当于科尔沁沙地其它地区正常年的降水量。因此,在这些地区大面积营造片状人工林,会导致水分亏缺问题。但若空留沙丘的中上部不营造乔木林,而利用水分条件比较好的沙丘下部、丘间低地进行带状造林或块状造林,则可能保持水分平衡,促进成林。