硅肥对超级早稻产量形成和部分生理特性的影响

以超级早稻组合株两优819(倒伏敏感品种)与陆两优996(抗倒伏品种)为材料,研究了硅肥对超级早稻产量形成和生理特性的影响.结果表明:硅肥对超级早稻具有显著增产作用,株两优819与陆两优996增产幅度分别为6.71％～18.25％和9.32％～21.89％.增产的主要原因在于施硅肥提高了叶面积指数与干物质积累量及物质转换率,协调了库源关系；硅肥能改善超级早稻生理特性,主要表现在叶片叶绿素含量、可溶性总糖含量与硝酸还原酶活性的提高及根系体积的增大等方面；施氮150 kg/hm2条件下施硅肥的增产和改善生理特性效果更好,且陆两优996效果比株两优819更好.     

硅肥对超级早稻氮利用效率的影响

以超级早稻组合株两优819（倒伏敏感品种）与陆两优996（抗倒伏品种）为材料,研究了硅肥对超级早稻氮利用效率及氮累积的影响。结果表明：在不施氮和施氮条件下施硅,能使超级早稻氮素累积量、氮肥利用率、氮素吸收效率、氮肥效率及氮素利用效率提高,而氮生理效率略有降低;施硅对两个超级早稻品种叶、茎、穗含氮量的影响与施氮量有关;在施氮150kg/hm2条件下施硅,对两个超级早稻品种氮利用效率及氮累积的影响效果最大。因此,在超级早稻生产过程中,氮硅肥合理配施有利于提高肥料利用率。     

施氮量对超级早稻产量形成与氮利用效率的影响

以株两优819和陆两优996为材料,研究了施氮量对超级早稻产量形成、稻米品质与氮利用效率的影响.结果表明：（1）施氮使超级早稻显著增产,株两优819增产的原因是提高了每穗粒数,而陆两优996增产的原因是提高了每穗粒数和千粒重;（2）两组合N 225 kg/hm2处理较N 150 kg/hm2处理显著减产;（3）两组合稻米蛋白质含量随施氮量增加而升高,直链淀粉含量随施氮量增加而降低;（4）超级早稻产量与叶面积、干物质积累量呈正相关,与粒叶比呈负相关;（5）随施氮量增加,两组合的氮素累积量显著提高,氮肥利用率、氮肥效率、氮素吸收效率、氮生理效率、氮素利用效率显著降低.本试验条件下,施N150 kg/hm2能使超级早稻获得较高产量,同时获得较高氮肥利用率、氮素吸收与利用效率.     

超级杂交早稻陆两优996在湘北平湖区的表现及高产栽培技术

两系超级杂交早稻陆两优996在湘北平湖区种植表现出耐寒、耐肥、高产等特点,生产上采用旱育保姆育壮秧、宽行窄株移栽、平衡施肥等技术措施,早稻最高产量达到9 337.5 kg/hm2.介绍了陆两优996的特征特性和高产栽培技术.     

行株距配置对超高产早晚稻产量的影响

 在30万蔸/hm2（早稻）和25万蔸/hm2（晚稻）密度下,以超高产早稻陆两优996、淦鑫203和超高产晚稻淦鑫688、天优华占为试验材料,研究了3个施氮水平下不同行株距配置对超高产早、晚稻产量的影响。不施氮时,供试的4个品种（组合）均在窄行距时产量最高;施氮条件下,淦鑫203在中行距时产量最高,陆两优996和天优华占在宽行距和窄行距时产量较高,而淦鑫688在窄行距时产量较高。不同行株距配置对陆两优996和天优华占产量的影响主要是通过影响有效穗数,对淦鑫203主要通过影响每穗粒数,而对淦鑫668则主要通过影响结实率来实现。品种间对行株距配置响应的差异与淦鑫203的每穗粒数较少、成穗率较低,而陆两优996和天优华占的每穗粒数较多、成穗率较高,淦鑫688的叶面积指数较高有关。早稻陆两优996的适宜行株距为33.0 cm×10.0 cm或20.6 cm×16.0 cm,淦鑫203为25.4 cm×13.0 cm;晚稻天优华占为40.0 cm×10.0 cm或20.0 cm×20.0 cm,淦鑫688为20.0 cm×20.0 cm。     

施硅对超级杂交稻抗倒性的影响

研究了超级杂交稻准两优527、两优0293在3种不同的施硅水平下生育后期的抗倒伏能力、抗倒形态及生理性状指标变化情况,结果表明:施硅对提高超级杂交稻的抗倒伏能力作用明显,其中以施用中量硅肥的处理(施五水偏硅酸钠300 kg/hm2)效果较好;两优0293的抗倒伏能力在各时期均明显强于准两优527;超级杂交稻生育后期随生育进程的后移,单株抗折力明显下降,倒伏指数明显上升,降低株高、单株生物量和茎鞘物质输出率,增加茎鞘干重有利于提高超级杂交稻生育后期的抗倒伏能力,降低倒伏风险.     

不同超级稻品种产量形成及其氮素吸收差异研究

以江西省水稻生产上推广的几个超级早稻、超级晚稻品种为材料,研究了长江中下游双季稻区不同超级稻品种产量形成、干物质生产及其氮素吸收特性。结果表明,同一栽培条件下,不同超级早、晚稻品种间干物质生产与转运、产量形成及氮素吸收存在一定的差异,生产100 kg籽粒所需的氮量差异不大。相关分析表明,超级早、晚稻总干物质积累量、茎叶干物质输出率和转换率与其产量均呈显著正相关。适宜在江西地区种植的超级早、晚稻品种分别为陆两优996、金优458和钱优1号、天优华占。     

高产两系杂交早稻新组合陆两优996的选育

陆两优996是以两用核不育系陆18S作母本,用大豆DNA导入水稻品种264-7育成的996作父本配制而成的杂交早稻新组合。该组合株叶形态优良,生育期比金优402短1~2 d,在湖南省2 a区试中平均比对照金优402增产7.75%,中抗稻瘟病,适应性广。2005年2月通过湖南省农作物品种审定委员会审定。介绍了陆两优996的选育过程、主要特征特性和栽培制种技术要点。     

不同施氮量对超级杂交早稻陆两优996抗瘟性和产量的影响

以超级杂交早稻陆两优996为材料,研究不同施氮量对其稻瘟病抗性和产量的影响。结果表明:随着施N量的增加,病穗率和病情指数并无明显的变化规律,但5级瘟穗率逐渐升高,当施N量过大时(270 kg/hm2)病穗率和病情指数都最高;施N量在0~180 kg/hm2范围内产量随着施氮量的增加而增加,施N量超过180 kg/hm2后产量随着施氮量的增加反而下降;综合考虑稻穗病发病情况、产量和经济效益,陆两优996以施N量90~135 kg/hm2为好。     

超级杂交早稻陆两优996亲本异交特性研究

对超级杂交早稻陆两优996亲本异交特性研究表明,陆两优966父母本的花时早而集中,花时相遇较好,但两者群体抽穗历期差异较大,花期相遇不太理想;母本陆18S的柱头体积大、外露率较高,但生活力较低;包颈程度轻,颖间距和开颖角度较大,但张颖历期较短;父本996的花粉量较多。陆两优996亲本具有较高的异交结实潜力,在制种上应根据亲本特性采取相应的技术措施,提高制种产量。     

Lodging Resistance Related to Root Traits for Mechanized Wet-Seeding of Two Super Rice Cultivars

Mechanical hill wet-seeded rice machine is beneficial for establishing and growing uniform rows of seedlings.However,there is limited knowledge regarding the effects of the establishment of furrows on growth,lodging and yield,and their relationships with root traits.In this study,field experiments were conducted during 2012 and 2013 using two super rice varieties(hybrid rice Peizataifeng and inbred rice Yuxiangyouzhan)under three furrow establishment treatments(T1,both water and seed furrows were established by the machine;T2,only seed furrows were established by the machine;and T3,neither water nor seed furrows were established by the machine).Lodging index,lodging-related traits,grain yield,above-ground dry weight and root traits were measured.The results showed that the lodging index was significantly affected by the treatments with furrows(T1 and T2).The strongest lodging resistance was detected in the mechanical hill wet-seeded rice with furrow treatment(T1)in both 2012 and 2013.Lodging resistance was strongly related to the breaking resistance.No significant difference was found in grain yield or dry weight of the mechanical hill wet-seeded rice.Therefore,the mechanical hill wet-seeded rice with furrow treatment increased rice lodging resistance,which was related to root traits.     

超高产粳稻品种抗倒伏性的初步研究

以沈阳农业大学水稻研究所培育的超高产粳稻品种为材料,研究了超高产粳稻品种的抗倒伏能力及与倒伏密切相关的各性状指标。结果表明:齐穗后30 d左右是水稻最容易发生倒伏的时期,株高与水稻倒伏指数呈极显著正相关,茎秆基部伸长节间性状与倒伏关系密切,茎秆维管束数目、厚壁细胞层数、淀粉和可溶性糖含量均对倒伏有一定影响。超高产粳稻品种沈农265和沈农9741与常规粳稻品种辽粳294和辽粳371相比,表现出较好的抗倒性能。     

水稻抗倒伏研究进展

倒伏是水稻生产中的一个严重问题。从水稻倒伏的主要影响因子、水稻抗倒伏机理、抗倒性评价及其遗传等方面，综述了水稻抗倒伏研究进展，提出了有待拓宽和深化研究的内容。     

Lodging-related morphological traits of hybrid rice in a tropical irrigated ecosystem

Hybrid rice (Oryza sativa L.) has been proven to be effective in increasing yield potential, but lodging often limits its yield in high-yielding environments. This study was conducted to determine genotypic variation in lodging resistance and lodging-related morphological traits among hybrid and non-hybrid check varieties, and to identify the key morphological traits associated with lodging resistance. Lodging behavior of 16 rice genotypes, including 12 hybrids and four inbreds, was studied at the International Rice Research Institute farm during the 2004 wet season (WS) and 2005 dry season (DS). Grain yield and visual score of lodging were determined at maturity. Lodging-related morphological traits were measured at 30 days after flowering. Large genotypic differences in lodging-related morphological traits were observed. Among these traits, dry weight per unit length, breaking resistance, and lodging index (bending moment/breaking resistance × 100) of lower internodes were significantly correlated with visual score of lodging. Several hybrids demonstrated high lodging resistance although their average plant height was over 120 cm. The lodging-related morphological traits and visual score of lodging in these hybrids were comparable with those of the non-hybrid check varieties with strong lodging resistance. These results suggest that increases in dry weight per unit length and breaking resistance of lower internodes are primary targets for reducing lodging index, thus improving overall lodging resistance of hybrid rice in a breeding program.     

水稻秸秆还田和耕作方式对小麦抗倒伏能力的影响

为了解水稻秸秆还田与耕作方式对小麦抗倒伏能力的调节作用,分析了不同耕作方式(免耕、旋耕、浅翻耕、深翻耕)下水稻秸秆还田后小麦茎秆基部第1至第4节间主要物理性状及抗倒性的变化.结果表明,水稻秸秆还田后小麦株高降低,茎秆节间变短,基部节间茎秆抗折力增强,花后倒伏指数降低,抗倒性提高,尤以深翻耕处理表现最好;茎秆基部节间茎壁加厚,茎秆干重增加,充实度提高,从而增强了茎秆抗折力.     

水稻倒伏研究及其影响因素分析

倒伏是水稻生产中普遍存在的问题,已成为高产稳产的重要限制因素之一。倒伏所造成的损失与水稻生长环境和倒伏的发生时期有关。倒伏是一个综合的、复杂的现象,它受到外界环境、栽培技术以及本身特性等多重影响。适宜的生长环境可以促进水稻生长和产量的提高,但会引发倒伏或使倒伏程度加重。鉴于倒伏对产量、品质的严重影响。本文综述了近年来国内外关于水稻倒伏的类型、水稻倒伏构成因素以及提高水稻抗倒伏能力的各种措施,展望了水稻抗倒性研究的方向。     

Practices and Prospects of Super Hybrid Rice Breeding

The great progress in super rice breeding both in China and other countries has been made in recent years. However, there were three main problems in super rice breeding: 1) the super rice varieties were still rare; 2) most super rice varieties exhibited narrow adaptability; and 3) current breeding theories emphasized too much on the rice growth model, but they were unpractical in guidance for rice breeding. According to the authors’ experience on the rice breeding, the breeding strategies including three steps (super parent breeding, super hybrid rice breeding and super hybrid rice seed production) were proposed, and the objectives of each step and the key technologies to achieve the goals were elucidated in detail. The super parent of hybrid rice should exhibit excellent performance in all agronomic traits, with the yield or sink capacity reached the level of the hybrid rice control in regional trials. The super hybrid rice combination should meet the following criteria: good rice quality, wide adaptation, lodging resistance, resistance to main insects and diseases, and the yield exceeded above 8% over the control varieties in the national and provincial regional trials. To achieve the goal, the technical strategies, such as selecting optimal combination of the parents, increasing selection pressure, paying more attention to harmony of ideal plant type, excellent physiological traits and all the agronomic traits, should be emphasized. The yield of seed production should reach 3.75 t/ha and 5.25 t/ha for the super hybrid rice combinations derived from early-season and middle-season types of male sterile lines, respectively. The main technologies for raising seed production yield included selecting optimum seed production site, using the male sterile line with large sink capacity and good outcrossing characteristics, and improving the amount of the pollen by intensive cultivation of the male parent. According to the technologies of the three-step breeding on super hybrid rice, two super rice parents, including a male parent 996 and a thermo(photo)-genic male sterile [T(P)GMS] line C815S, were bred. Furthermore, a super early hybrid rice combination, Luliangyou 996, which could be used as a double-season early rice variety in middle and lower reaches of the Yangtze River, China, was bred by using the super rice variety 996 as the male parent, and several hybrid rice combinations with higher yield than control variety in regional trials both of Hunan Province and state were bred with the T(P)GMS line C815S as the female parent.     

Relationship Between Lodging Resistance and Chemical Contents in Culms and Sheaths of Japonica Rice During Grain Filling

To understand the relationship between lodging resistance and chemical component contents in culms and leaf sheaths of rice,the physical strength and maximum bearing capacity of culm,and the contents and amounts of potassium(K),silicon(Si)and soluble sugars in culms and leaf sheaths were investigated using four japonica rice varieties with different lodging resistance characteristics during grain filling.There were significant differences in the total amounts of K,Si and soluble sugars in culms and leaf she...