水稻种子耐干性机理的研究

以籼稻C38、粳稻京21、杂交稻秋优3为材料,进行种子超干储藏特性的研究,进而探讨种子耐干性的机理。通过超干水稻种子生活力和活力的比较,发现籼稻C38耐干性较强。超干有利于保持种子抗氧化酶系统的完整性,因此超干能提高种子的耐储性。对超干种子可溶性糖含量与组分进行分析,结果表明随着种子含水量的降低,蔗糖含量增高,多糖和葡萄糖含量降低,籼稻C38的蔗糖含量明显低于粳稻京21和杂交稻秋优3。用热重仪测定的种子含水量与烘干法得到的数据相吻合,用差示热量扫描仪测定束缚水/自由水的比例和玻璃化转变温度Tg,发现籼稻C38的Tg高于粳稻京21和杂交稻秋优3,籼稻C38束缚水/自由水比例大于粳稻京21和杂交稻秋优3,而束缚水/自由水的比例与耐干性成正相关。由此表明,耐干性在不同的水稻品种间有明显的差异,籼稻C38的耐干性较强。     

旱作对籼粳稻产量及相关性状的影响

研究了旱作对籼、粳亚种间产量及其相关性状的影响,并用逐步回归分析法建立亚种间水稻旱作的产量回归模型。研究表明,旱作在生育期、分蘖数、有效穗、穗长、株高、总粒数、结实率、千粒重等性状上对籼型品种的影响较粳型品种的影响大。在旱作条件下,粳型产量总体表现比籼型品种高。     

Analysis of Vietnamese rice germplasm provides an insight into Japonica rice differentiation

Genetic differentiation among landraces of rice in northern Vietnam that lie in the centre of genetic diversity of Asian cultivated rice was analysed using DNA markers, and morphological and physiological traits to obtain an insight into the genetic differentiation of Asian rice. Principle coordinate analysis, based on nuclear RFLP data, divided Vietnamese rice varieties into three groups, designated A, B and C. Chloroplast DNA variation discriminated group A, which corresponded to the Indica rice varieties, from both groups B and C, which corresponded to the Japonica rice varieties. Physiological characteristics for Indica‐Japonica and tropical‐temperate Japonica discrimination suggested groups A and B consisted of typical Indica and Japonica varieties, respectively, while the characteristics of group C were distinct from those of the other two groups. This suggests that the genetic differences between groups B and C represent a new aspect of genetic variation that has not been previously reported in Japonica rice. Groups C and B corresponded with upland and lowland rice, respectively. Eight marker loci were associated with upland‐lowland differentiation in Japonica rice. Highlighted chromosomal regions might have been selected during the history of cultivation under different cultural conditions, and thus contain genes related to adaptation.     

嘉兴水稻海南育种的品质差异及育种策略

经过对嘉兴香米、苏95-22等7个非糯水稻品种(系)海南和嘉兴不同育种条件下成熟稻米品质分析,发现与稻米商品品质密切相关的同一品种的直链淀粉含量、外观品质、食味等性状嘉兴和海南截然不同。分析其原因是抽穗后温度条件不同所致,即灌浆时期气温升高或降低,其直链淀粉含量、外观、食味等性状也随之发生变化。无论是早籼稻,还是晚粳稻,这种变化趋势完全一致。根据这一情况,异地育种或不同季节选育品种时,应根据温度条件不同,建立相应的检测指标,以提高针对性、减少品种选育的盲目性。其次,对优质水稻生产来说,改善栽培条件便可进一步提高稻米的食用品质。     

生态条件对籼粳稻杂交F2代亚种特性分化与经济性状的影响

以籼粳稻杂交F2代群体(七山占/秋光)为供试材料,2010年分别在广东省与辽宁省同年种植,研究籼粳亚种属性和经济性状的分化规律以及两者之间的相互关系.结果表明,广东和辽宁2个生态地区群体,亚种特性呈相似正态分布,未出现偏分现象,说明在F2群体中遗传重组对群体的作用呈主导性.经济性状发生较显著的分化,穗数、千粒重、1次枝梗数及粒数辽宁地区显著高于广东,而产量、穗粒数及结实率呈现相应生态条件的偏向性,籼型及偏籼型在广东地区较高,粳型及偏粳型在辽宁地区较高,说明在籼粳交F2代中不同的籼粳类型存在较为显著的生态适应性,并且该结果在相关性分析也得了验证.此外,对进一步研究籼粳分化机制的相关问题进行了讨论.     

亚洲栽培稻的核DNA、线粒体DNA和叶绿体DNA籼粳分化的比较研究

本研究对来自１２个国家的７４份亚洲栽培稻进行了核ＤＮＡ,线粒体ＤＮＡ的ＲＦＬＰ分析和叶绿体ＤＮＡ的ＯＲＦ１００的ＰＣＲ分析结果表明参试的７４个栽培稻品种,除ＣＲ１４７的线粒体基因组的类型较为特殊外,其它７３个品种的细胞核基因组,线粒体基因组,叶绿体基因组均可分为籼粳两种类型,可见籼粳分化是栽培稻核ＤＮＡ,ｍｅｔ ＤＮＡ和ｃｐＤＮＡ遗传分化的主流,同一品种３个ＤＮＡ的籼粳属性即有一致的,又有不一致的     

Indica-Japonica differentiation of paddy rice and its relationship with heterosis

The Indica‐Japonica differentiation of three photoperiod‐sensitive and/or thermosensitive genetic male‐sterile rice (PGMS or TGMS, respectively) lines and 47 male parental lines from seven ecotypes were studied for their restriction fragment length polymorphism marker data to determine which ecotype crosses with the three PGMS and/or TGMS lines could lead to higher yield potential, and to estimate the relationship between the Indica‐Japonica differentiation of parents and heterosis in grain yield and its components. The results indicated that hybrids derived from ‘N422s’ and the early‐middle ripening Indica varieties from southern China, and hybrids between ‘Pei'ai64s’ and three Japonica ecotypes, including North‐eastern Japonica varieties, restoring lines of Japonica hybrid rice and north China Japonica varieties, showed the highest grain yields. There was less variation of yield among the F1s between ‘108s’ and the seven ecotypes than among the other F₁s. Highly significant positive correlations between heterosis of the F₁ yield and genetic distance of the parents were detected, although the correlation between F₁ yield performance and genetic distance did not reach a significant level. Considerable variation of correlation between heterosis and genetic distance was also detected in the Indica × Indica crosses and Indica × Japonica crosses. There was much higher correlation (r = 0.63) between the F₁ yield performance and the genetic distance of parents in the Indica × Indica crosses than in the others. It is proposed that a genetic distance of 0.4‐0.8 between the two parents of hybrid rice might be appropriate not only for F₁ performance, but also for heterosis.     

应用双单倍体克服籼粳交的不亲和性初探

通过对籼粳交Ｆ１体细胞愈伤组织的秋水仙素处理和四倍体花药培养，建成了水稻四倍体诱导及双单倍体分解系统。应用这一系统获得了４４个籼粳交组合的双单倍体及其自交４后代。对这些双单倍体及其后代的遗传分析表明，籼粳交育性可能受寡基因控制，双单倍体途径通过改变正常的世代交替过程，能部分克服籼粳交的不育性及倾籼或倾粳的偏态分离，并具有比Ｆ２更丰富的遗传多样性。在双单倍体一代群体中，育性正常的植株约占４０％，这是     

除草剂对转bar基因水稻抗性愈伤的筛选和早期苗的鉴定

设立不同的PPT浓度梯度分别对来自籼稻珍汕97B和粳稻台北309、日本晴成熟种子胚的愈伤组织进行天然抗性试验,并对转bar基因的幼苗进行了Basta涂抹试验,以便对转化苗早期初步鉴定.结果表明:籼稻和粳稻均表现出一定的对PPT的天然抗性,转bar基因水稻在筛选抗性愈伤时,以浓度为10mg/L的PPT较为合适;而粳稻则必须提高至20mg/L为宜.叶片涂抹Basta鉴定转化植株时,以0.125%的浓度方才有效,且籼、粳稻的反应无差异.     

栽培稻的基因型差异程度和分类

本文利用来自一个籼/粳交(圭630/02428)的双单倍体(DH)系和由多种类型的籼、粳品种(系)组成的对照组,从分子水平上研究亚洲栽培稻的基因型差异。结果表明,栽培稻中存在两种主要的差异类型,即质的差异和量的差异。前者主要存在于籼、粳分化程度比较高的对照组中,85%以上的有关位点已经发生了籼或粳的分化趋向;后者主要存     

几个美国光壳稻的亲和性分析

将５个籼粳两种类型的美国光壳稻ＲＡ７３,ＫａｔｙＭａｒｓ,Ｌａｇｒｕｅ,Ｎｅｗｎｏｎｎｅｔ和中国籼稻特青配成一组完全双列杂交,进行Ｆ１代结实率配合力分析,结果表明：籼型光壳稻ＲＡ７３的结实率一般配合力最高,与粳型光壳稻Ｍａｒｓ杂交特殊配合力也最高,结实率达８７．７％,有较好的亲和性,比前人报道的广亲和品种Ｎｅｗｂｏｎｎｅｔ与粳稻Ｍａｒｓ杂交的结实率（５６．５％）极显著地提高,ＲＡ７３可用于籼粳杂交     

水稻广亲和与非广亲和品种蛋白质的比较研究

本文对水稻广亲和与非广亲和品种种子蛋白质组分进行了单向和双向电泳分析，获得了较清晰而稳定的结果。发现籼稻和粳稻亚种间电泳图谱有明显差异，而广亲和与非广亲和品种间蛋白组分未发现规律性的差异。又用SDS-PAGE方法比较了广亲和与非广亲和品种水稻叶片、花药的蛋白组分，未现4个广亲和品种水稻花药蛋白质中均有一条共     

Morphological Classification of Traditional Philippine Upland Rice Cultivars in Upland Nurseries Using Cluster Analysis Methods for Recommendation, Breeding and Selection Purposes

Using eight morphological parameters with six cluster analysis methods, a set of 21 traditional and four improved Philippine upland rice cultivars (cvs) could be separated into five groups: (1) improved semi-dwarf plant type, (2) improved or 'moderately modified' (short) Indica plant type, (3) traditional tall Indica plant type, (4) traditional tall Japonica plant type and (5) traditional short Japonica plant type. The results emphasized the importance of the separation into Indica and Japonica plant types, but the cultivars could be classified more accurately using growth characteristics such as tillering ability, followed by plant height and leaf area parameters. The clusters containing Indica cvs consistently showed a higher tiller number per plant, a higher growth stage (DC classification) and narrower leaves than clusters with Japonica cvs. The parameters culm length, plant height, leaf area, leaf length and width were represented in subgroups with both long and short expression of the respective characteristic. Use of the existing variability of morphological traits within the group of traditional upland rice cvs should be beneficial in recommendation, breeding, selection and development of upland rice cvs for the different rice ecosystems as well as for the upland rice/rice blast pathosystem.     

Evaluation of CropSyst for simulating the yield of flooded rice in northern Italy

Research on rice cropping systems carried out in Europe has to face the great variability of pedo-climatic conditions, and the linked abundance of cultivated varieties, characteristic of the high latitudes-temperate areas where rice is traditionally grown.

Dynamic simulation models can provide an useful tool for system analysis needed to improve the knowledge, the agronomic management and crop monitoring.

For calibrate and validate CropSyst (never used for rice), a process-based simulation model, for Indica-type and Japonica-type varieties, data obtained from five field experiments, carried out in Northern Italy between 1989 and 2002, were used.

Plants were sampled during the life cycle from rice plots of five cv Loto, Cripto, Ariete, Drago, Thaibonnet and Sillaro, maintained at potential production, to determine some important crop variables and parameters such as aboveground biomass (AGB), leaf area index, specific leaf area, harvest index, the date of the main phonological stages.

At the end of the calibration process to the parameters (the others were set to the default value, taken from the Literature or measured) optimum mean daily temperature for growth, specific leaf area (for Japonica varieties), stem/leaf partition coefficient (empirical), leaf duration, were assigned the following values: 28 and 27 °C respectively for Japonica and Indica varieties, 27 and 29.5 m² kg⁻¹ respectively for Japonica early and medium-late varieties, 4.5, 3, 1.5 for Japonica early, medium-late and Indica varieties, 700, 850, 950 °C-days for the three groups of varieties.

The assessment of model performances has shown average RRMSEs of 20 and 22% at the end of calibration and for the validation process; the modelling efficiency is always positive and the coefficient of determination always very close to 1. General improvements will be achieved by the model by considering the thermal profile (strongly influenced by flooding water at mid latitudes) evolving in and over the canopy.     

Photosynthetic ability,grain yield and an esterase band in rice genotypes

Summary Four Indica and one Japonica (Tainung 67) of rice (Oryza sativa L.) varieties had an esterase band (tentatively designated as E₁), and also had higher photosynthetic ability than other five Japonica varieties without E₁ band. The F₁ plants of Tainung 67 × Mineyutaka (low photosynthetic ability, no E₁ band) showed E₁ band and a low photosynthetic ability. Of 34 F₂ plants, 28 had E₁ band, but 6 had no E₁ band of which 5 plants showed a low photosynthetic ability. These results suggest that an esterase gene and one of the photosynthesis gene are linked, and the gene for low photosynthetic ability is dominant.Among 42 new Japonica strains and 2 control varieties bred in Taiwan, most genotypes with E₁ band showed higher grain yield potential (grain field/growth days) in local test.Esterase band may be used as a marker for high photosynthesis and grain yield ability in breeding.     

转cry1C基因抗虫超级粳稻田间目的基因表达及抗螟虫性

为了研究转基因抗虫超级粳稻田间目的基因表达及抗螟虫性,将10个来自于不同独立抗性愈伤组织的转cry1C*基因抗虫超级粳稻品系种植于田间,利用实时荧光定量PCR方法检测孕穗期叶片、茎鞘和幼穗等器官目的基因mRNA,利用酶联免疫吸附(ELISA)法检测孕穗期叶片、茎鞘和幼穗及收获后糙米的Cry1C蛋白,利用田间目测调查二化螟危害的白穗率。结果及分析显示,转基因超级粳稻不同品系及不同器官cry1C*基因田间表达量明显不同,cry1C*基因mRNA表达量叶片＞茎鞘＞幼穗,蛋白质表达量叶片＞茎鞘＞幼穗＞糙米。转基因超级粳稻田间目的基因表达,在mRNA水平和蛋白质水平,不同器官间存在正相关关系,各器官Cry1C蛋白质含量和糙米Bt蛋白质含量呈正相关。在本研究范围内,不论转基因粳稻植株Cry1C蛋白质含量高或低的品系,田间均表现为高抗二化螟。培育转基因抗虫粳稻品种时,注意对目的基因适量表达的抗虫基因型的选择。     

Diversity analysis for resistance of rice (Oryza sativa L.) to blast disease [Magnaporthe grisea (Hebert) Barr.] using differential isolates from the Philippines

A wide variation in resistance to blast disease caused by Magnaporthe grisea (Hebert) Barr. ( Rossman et al. 1992 ) was found using 922 rice ( Oryza sativa L.) varieties collected mainly from Asia. These were classified into six varietal groups, termed clusters A–F, according to Ward's hierarchical cluster analysis, based on the reaction pattern to 20 standard differential blast isolates from the Philippines. The most susceptible two clusters, B and C, dominated in varieties from the Far East (Japan). Varieties from East Asia and Southeast Asia occurred less frequently in B and C clusters than those of Japan, and more frequently in E and F clusters, which were the most resistant of the cluster groups. Varieties from South Asia showed the widest variation, occurring in all clusters but less frequently in cluster B. The cluster B varieties dominated in Japan and showed a high frequency of isozyme type VI, corresponding to Japonica type. In contrast, the frequency of cluster B was low in the groups with isozyme types I, II, III and V, which dominated in South Asia. Isozyme type I corresponds to Indica type varieties. The distribution of resistance corresponded to the geographical distribution of rice varieties and might be related to differentiation into Indica and Japonica types. These findings will provide useful information for understanding the variation in blast resistance at the global level.     

Increased regeneration from NaCl-tolerant callus in rice

Summary NaCl-tolerant calli were selected from two Japonica and two Indica rice (Oryza sativa L.) cultivars on basal media containing 6,000, 9,000, 12,000 or 15,000 ppm NaCl. Frequency of callus formation decreased with the increase of NaCl in the medium, especially in Indica. About half of the calli of Japonica cultivars selected on NaCl-ammended media survived 20,000 ppm NaCl but none of the Indica callus survived. In Japonica, more plants were regenerated from calli selected on all concentrations of NaCl media than from NaCl-free medium. Concentration of Cl^- in callus increased dramatically with increased NaCl content but peroxidase activity decreased.     

水稻不同品种蛋白质亚基百分含量的差异性研究

摘 要：主要通过SDS-PAGE电泳检测方法,探讨水稻谷蛋白PB-II亚基和醇溶蛋白PB-I亚基含量的差异。试验结果表明,不同水稻品种的蛋白质亚基含量不同。龙粳8号的醇溶蛋白亚基含量为11.53%;富士光和松99-135的醇溶蛋白亚基含量为13.39%和13.61%,居同一水平,其谷蛋白亚基含量较高为72.87%和69.52%,是富含谷蛋白的PB-II蛋白质体;绥粳3号的醇溶蛋白亚基含量相对较高为15.25%。对水稻品种谱带进行13kDa单一亚基分析,绥粳3号和籼粳交的特优21在单一亚基分析中,其13kDa醇溶蛋白亚基含量明显高于其它几个品种。不同品种的13kDa醇溶蛋白亚基含量存在差异。     

水稻粳型恢复系 C57的选育

1.粳恢 C57具有较高配合力,杂种一代具有较强优势,花粉量大,有利于提高异交结实率,是当前较好的广谱恢复系。2.籼粳杂交复交与配子利用的“架桥”制恢方法,在杂种一代提供利用部分籼核的机率,丰富了遗传基础,为间接利用籼粳杂种优势及其优良性状开辟了途径。3.粳恢 C57对杂种一代的株型、叶型、高产的“库”和“源”以及适应