不同水稻品种蛋白质含量的分析

通过对6个不同品种间籽粒蛋白质含量在同一灌浆期的比较,各个品种籽粒蛋白质含量在灌浆的四个时期的动态变化分析,以及籽粒蛋白质含量的变化规律与灌浆速率的关系分析,结果发现：每个品种的蛋白质积累过程中都有一个明显猛增的飞跃期,且多处于灌浆速率最快时期以外（后、末期）,且XR243增幅大,营养品质高,可作为培育高蛋白杂交后代的首选亲本品种。相关分析表明,籽粒可溶性糖含量和蛋白质含量之间不存在显著性相关,说明水稻自抽穗到完全成熟,碳、氮代谢基本上是两个相对独立进行的过程。     

干旱胁迫下不同类型小麦灌浆期营养物质积累动态

为了解干旱对不同类型小麦籽粒灌浆期糖类、淀粉、蛋白质和微量元素的动态规律,明确干旱对营养物质在高产小麦、优质小麦和节水小麦灌浆过程中的差异,以黄淮北片麦区的小麦品种冀麦325、冀麦418、冀麦323为试验材料。选取同一天抽穗、开花的植株进行标记,于花后7～31 d每6 d取各品种籽粒样本,研究了灌浆期间干旱对籽粒中可溶性总糖、蔗糖、葡萄糖、果糖、蛋白质、Fe、Zn、Mn、Cu含量、直链和支链淀粉积累量、淀粉积累速率及淀粉合成关键酶活性的影响。结果表明,在灌浆过程中,干旱胁迫显著降低了小麦籽粒蔗糖和葡萄糖的含量,对果糖含量的影响相对较小,高产品种冀麦325的蔗糖和果糖受干旱影响较小。干旱胁迫降低了小麦籽粒支链淀粉和总淀粉含量,对直链淀粉含量的影响相对较小。干旱胁迫对高产品种和优质品种淀粉含量的影响明显大于耐旱品种冀麦418。干旱胁迫在灌浆初期和中期提高了淀粉合成酶的活性,中后期活性较灌溉对照迅速下降。随籽粒灌浆的进行,4种微量矿质元素的含量呈下降趋势,在小麦籽粒中的表现为MgFeZnMn。冀麦325籽粒的Fe、Zn和Mg积累量较高。研究干旱条件下不同类型小麦籽粒灌浆过程中营养物质积累差异,为优化栽培措施,实现专用小麦优质、高产、节水提供理论数据和参考依据。     

不同播期对百农矮抗58籽粒可溶性糖、淀粉积累的影响

研究了不同播期对百农矮抗58籽粒可溶性糖、直链淀粉、支链淀粉、总淀粉积累的影响以及之间的关系.结果表明,播期对矮抗58小麦籽粒中可溶性糖含量、总淀粉含量、淀粉积累速率和直链/支链淀粉比值有较大影响.开花至成熟期,籽粒中可溶性糖含量随着总淀粉含量的增加而降低,且可溶性总糖含量与籽粒淀粉含量和籽粒淀粉积累速率均呈显著或极显著正相关;推迟播种期,矮抗58灌浆前中期籽粒淀粉积累速率提高,籽粒中总淀粉含量增加,但是会使灌浆期相对缩短,灌浆中后期籽粒中粉积累速率过早迅速下降,总淀粉含量降低.     

脱水敏感的黄皮种子在发育过程中的碳水化合物变化研究

脱水敏感的黄皮种子发育至生理成熟时淀粉积累达最大值,但其胚轴中淀粉含量远低于子叶且在种子成熟以后明显下降。花后65d子叶中可溶性糖含量最高而胚轴中可溶性糖随种子发育而一直上升。还原性葡萄糖和麦芽糖含量随种子发育而逐渐降低．非还原性果糖和蔗糖则逐渐增加。生理成熟期子叶中还含有较多的水苏糖和棉籽糖。外源ABA可提高成熟林子子叶中蔗糖的含量和未成熟种子的淀粉含量、但不能提高种子的耐脱水能力。因此我们认为黄皮种子的碳水化合物变化与其所在组织（子叶和胚轴）的不同代谢模式有关,而不是与种子的脱水敏感性有关。     

甜玉米与普通玉米籽粒发育过程中碳水化合物及氨基酸消长规律的比较研究——Ⅰ.籽粒灌浆特性及碳水化合物消长规律

不同类型玉米籽粒灌浆过程一致,差异主要表现在量上。甜玉米,尤其是超甜玉米具有灌浆速度慢、持续时间短及脱水慢等特点。随着籽粒灌浆的进行,蔗糖及可溶性糖含量迅速增加至最大值,尔后下降,还原糖则一直下降。类型间差异主要表现在蔗糖含量上。超甜玉米维持高糖含量的时间要长于普甜玉米,温度影响甜玉米籽粒中糖分的积累进程,而对最大含量无甚影响,各品种可溶性糖含量达最大值所需的有效积温数量较稳定。水溶性多糖含量相差极大,普甜玉米一直迅速增加,而超甜玉米及普通玉米则很低且变化很小。     

潮盐土条件下不同小麦品种（系）子粒品质差异分析

为探明潮盐土条件下不同小麦品种（系）间的子粒营养物质含量及其积累过程,以小麦品种连麦7号、淮麦33和小麦品系连麦抗1为材料,研究了潮盐土条件下小麦子粒蛋白质及其组分含量、氨基酸积累量、淀粉含量及灌浆期间的动态变化。结果表明,连麦7号蛋白质总量及各组分含量均显著高于其他2个品种（系）,醇溶蛋白和谷蛋白含量在3个品种（系）间均存在显著差异。不同小麦品种（系）各氨基酸积累量,以谷氨酸积累量最高。连麦7号18种氨基酸积累量均高于淮麦33和连麦抗1,以脯氨酸差异最大。连麦抗1谷氨酸和苏氨酸积累量高于淮麦33。子粒灌浆期间淀粉含量表现为连麦抗1>淮麦33>连麦7号,其中总淀粉和支链淀粉含量随子粒发育先升高后降低,而直链淀粉含量不断增加。综合以上结果,在潮盐土条件下,连麦7号的子粒品质优于淮麦33和连麦抗1。     

木薯叶片可溶性糖含量与块根淀粉积累的关系

试验以辐选01，华南5号(SC5)，新选048，新选056，南洋红（SC201），华南205(SC205)，GR891，华南124（SC124）为材料，分别在块根形成期、块根膨大期和工艺成熟期测定叶片可溶性糖含量和块根淀粉含量，探讨木薯叶片可溶性含量与块根淀粉积累的关系。结果表明，从块根形成期到工艺成熟期，叶片可溶性总糖含量与块根淀粉积累都逐渐增加，叶片可溶性总糖含量与块根淀粉积累呈正相关，从块根膨大期到工艺成熟期，叶片还原糖含量逐浙增加，与块根淀粉积累呈正相关，而叶片蔗糖含量逐浙降低。与块根淀粉积累呈负相关。8个品种都有同样的趋势。     

甘薯品质的初步研究

对部分甘薯品种品质的研究结果表明:(1) 甘薯品种(系)间薯块内的淀粉、蛋白质、氨基酸、胡萝卜素、维生素C、可溶性糖等成分存在明显的差异;(2) 环境条件对甘薯营养成分有一定的影响。同一品种在不同地点种植,其薯块内的淀粉和蛋白质含量存在明显差异,同一品种在不同年份种植,其薯块内的蛋白质、可溶性糖含量差异较大,而淀粉、维生素C含量差异较小;(3) 薯块内的蛋白质含量与17种氨基酸、可溶性糖含量呈显著正相关。     

春小麦不同品质类型氮的吸收、转化利用及与籽粒产量和蛋白质含量的关系

以不同品质类型春小麦为材料,研究产量和蛋白质形成过程中营养体各器官氮的水平动态以及氮的转化和利用效率。结果表明,植株营养体各器官干物质总的积累趋势为开花期开始增加,达高峰后逐渐下降至成熟;氮的含量变化为开花期最高,随籽粒灌浆逐渐下降,成熟时降至最低。籽粒氮含量变化呈“V”型曲线,籽粒氮素积累呈“S”型     

源库改变对小麦籽粒蛋白质,淀粉含量及产量的影响

利用蛋白质含量及产量各不相同3个春小麦品种．研究了源库改变对淀粉、蛋白质沉术；及单侏产量的影响．结果表明：源库改变明显地影响着籽粒蛋白质的含量，而对淀粉、可溶性糖含量影响不大；品种间蛋白质含量对源库变化的反应不同；千粒重的增减也因品种而异；淀粉的沉积主要受库的限制，而源库都影响着蛋白含量；旗叶在产量和蛋白形成中起着同样重要作用。     

大麦籽粒淀粉和β-葡聚糖积累特性研究

为研究大麦籽粒支链淀粉、直链淀粉和β-葡聚糖积累特性,及淀粉各组分与β-葡聚糖的关系,以2个皮大麦、1个裸大麦和1个糯裸大麦为试验材料,测定花后7、14、21、28d淀粉各组分及β-葡聚糖含量。结果表明,甘啤6号淀粉各组分含量随灌浆推进均逐渐升高,在成熟期达到最大值;甘垦啤7号和甘垦6号均呈先升高后降低趋势,在花后21d有1个峰值。糯大麦C 2-1直链淀粉含量显著低于非糯大麦;支链淀粉含量显著高于非糯大麦,整个灌浆期呈先升高后降低趋势。β-葡聚糖含量均随灌浆时间延长逐渐升高,成熟期含量最高;整个灌浆期糯大麦C 2-1含量显著高于非糯大麦。相关分析表明,直链淀粉/支链淀粉比值与β-葡聚糖含量呈极显著负相关,可以将直链淀粉/支链淀粉比值作为高β-葡聚糖品种选育的一个指标。Logistic方程拟合发现,直链淀粉、β-葡聚糖最终积累量与积累起势与有效积累时间有关,支链淀粉最终积累量取决于最高积累速率和平均积累速率。     

灌浆期高温对两种品质类型小麦品种籽粒淀粉合成关键酶活性的影响

以徐州26（高蛋白含量）和扬麦9号（低蛋白含量）2个不同品质类型小麦品种为材料，利用人工气候室模拟小麦花后高温条件，研究了灌浆期高温对籽粒淀粉积累及淀粉合成关键酶活性的影响。结果表明，与适温处理（20℃）相比，高温（28℃）显著降低了籽粒中总淀粉及支链淀粉的含量，而对直链淀粉含量的影响较小，导致支/直链淀粉的比例显著降低。高温提高了灌浆初期小麦籽粒中蔗糖合成酶（SS）和结合态淀粉合成酶（GBSS）活性，但明显降低了灌浆后期SS、GBSS和可溶性淀粉合成酶（SSS）活性。品种间相比，灌浆初期高温处理提高了扬麦9号籽粒GBSS活性，但显著降低了徐州26籽粒SSS活性，说明高温抑制2种类型小麦籽粒淀粉合成的酶学机制不同。此外，不同昼夜温差处理（8℃和12℃）间比较发现，高温下两品种籽粒淀粉含量没有明显差异，适温下两品种淀粉含量以温差较大的处理含量较高。灌浆中后期，高温下SS活性随温差增大而升高，SSS和GBSS则以温差小的处理较高；适温下3种关键酶活性均以温差大的处理为高。总之，灌浆期温度较温差对小麦籽粒淀粉合成的影响大。     

不同形态氮肥对春小麦品种籽粒淀粉及其组分的调节效应

以不同亚基组成且品质类型不同的6个春小麦品种（东农7742、新克旱9、泉224、辽10、Roblin和龙麦26）为试验材料,研究了淀粉及其组分积累规律、不同形态氮肥（酰胺态氮、硝态氮和铵态氮）对淀粉及其组分积累的调节效应及不同品种淀粉与蛋白质的消长关系。结果表明,供试HMW-GS组成品种的淀粉及其组分的积累存在基因型差异,     

Effects of High Temperature on Key Enzymes Involved in Starch and Protein Formation in Grains of Two Wheat Cultivars

High temperature is a major determinant of grain growth and yield formation in wheat. The present study was undertaken to investigate the effects of high temperature regimes on the activities of key regulatory enzymes involved in starch and protein accumulation in grains of two winter wheat (Triticum aestivum L.) cultivars Yangmai 9 and Xuzhou 26 with different protein contents. Four day/night temperature regimes of 34 °C/22 °C, 32 °C/24 °C, 26 °C/14 °C and 24 °C/16 °C were established after anthesis, resulting in two daily temperature levels of 28 °C and 20 °C and two diurnal temperature differences of 12 °C and 8 °C. The activities of glutamine synthase (GS) in flag leaves and glutamate pyruvic aminotransferase (GPT), sucrose synthase (SS), soluble starch synthase (SSS) and granule‐bound starch synthase (GBSS) in grains were measured during the periods of grain filling. High temperature reduced both content and yield of starch in grains, while enhanced protein content and reduced protein yield in grains. High temperature significantly enhanced the activities of SS and GBSS on 14 days after anthesis (DAA). High temperature affected SSS slightly in Yangmai 9, but reduced SSS activity markedly in Xuzhou 26 on 14 DAA. However, at the middle and late stages of grain filling, high temperature reduced the activities of SS, GBSS and SSS significantly in the two wheat cultivars. High temperature reduced GPT activity in grains in the two wheat cultivars, but reduced GS activity in flag leaves of Yangmai 9 and enhanced GS activity of Xuzhou 26 on 14 DAA. In addition, under the same high temperature level, SS activity was higher at 34 °C/22 °C, whereas the activities of SSS and GBSS were higher at 32 °C/24 °C. Also, diurnal temperature differences affected GPT and GS activities differently between the two cultivars. Under optimum temperature level, the activities of key enzymes for starch and protein synthesis were higher at 26 °C/14 °C. The activities of SS, SSS and GBSS significantly correlated with starch accumulation in grains, except for GBSS activity to starch content on 14 DAA. GPT activity was positively correlated with protein yield, and GS activity was negatively correlated with protein yield on 14 DAA, while the activities of both GPT and GS were negatively related to protein content in grains.     

不同氮效率水稻品种叶片光合作用及氮利用特征的差异分析

以扬稻6（氮高效品种）、武玉粳3（氮低效品种）为材料,在含有2.86mmol/L NH₄ ⁺溶液培养条件下,分别在开花期和灌浆期分析了中位叶、旗叶的净光合速率、氮同化酶的活性、叶片氮含量与转移率以及对子粒的贡献。结果表明：（1）旗叶的净光合速率显著高于中位叶;扬稻6旗叶的净光合速率显著高于武玉粳3,而中位叶净光合速率在品种间差异不显著。（2）硝酸还原酶活性（NRA）、谷氨酰胺合成酶活性（GSA）是中位叶高于旗叶、灌浆期高于开花期、扬稻6高于武玉粳3。从开花到灌浆期,旗叶可溶性糖含量呈增加的趋势,而中位叶可溶性糖含量呈减少的趋势。旗叶可溶性糖含量高于中位叶、扬稻6高于武玉粳3。可溶性蛋白含量呈下降的趋势,扬稻6可溶性蛋白含量高于武玉粳3。扬稻6、武玉粳3中位叶可溶性蛋白的转出率分别是50.3%、37.6%;旗叶可溶性蛋白的转出率分别是69.5%、44.4%。（3）中位叶总氮积累量显著高于旗叶、开花期显著高于灌浆期。扬稻6中位叶、旗叶氮转移量分别为35.6%、34.7%;武玉粳3中位叶、旗叶氮转移量分别为26.9%、35.3%。（4）去除中位叶,子粒氮分别比对照减少了6.9%（扬稻6）、4.6%（武玉粳3）;子粒产量分别比对照减少了7.3%（扬稻6）、4.9%（武玉粳3）。去除旗叶,子粒氮分别比对照减少了10.5%（扬稻6）和9.2%（武玉粳3）;子粒产量分别比对照减少了13.8%（扬稻6）、11.1%（武玉粳3）,表明旗叶对子粒氮和产量的贡献更大。总之,氮高效品种旗叶光合作用和氮同化能力显著高于氮低效品种,另一方面,其中位叶储存的氮也能及时转移到子粒中,提高了氮效率,这反映了不同氮效率品种氮素利用差异的机制。     

小麦花后弱光对籽粒淀粉积累和相关酶活性的影响

2005—2007年选用小麦品种济麦20和山农1391, 在大田试验条件下研究了花后不同阶段弱光对籽粒淀粉积累、淀粉粒分布及相关酶活性的影响。结果表明, 花后不同阶段弱光显著降低成熟期籽粒淀粉积累量, 但提高了籽粒直链淀粉含量。花后不同阶段弱光使籽粒A型淀粉粒比例显著增加, B型淀粉粒比例显著降低。不同阶段弱光处理对籽粒淀粉积累的影响程度不同, 灌浆中期的效应大于灌浆前期。Logistic方程拟合籽粒淀粉积累进程发现, 花后弱光对籽粒淀粉积累量的影响, 主要是通过影响其平均积累速率与活跃期积累速率, 而不是积累持续期。花后弱光显著降低小麦磷酸蔗糖合酶(SPS)、蔗糖合酶(SS)和腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)的活性。灌浆前期弱光使束缚态淀粉合酶(GBSS)、可溶性淀粉合酶(SSS)活性高于对照或与对照无显著差异, 而灌浆中期弱光使这两种酶的活性均显著低于对照。灌浆前期弱光减少了淀粉合成底物的供应, 系旗叶SPS活性、籽粒SS及AGPase活性下降所致; 而灌浆中期弱光除淀粉合成底物减少外, 籽粒淀粉合酶活性亦降低。     

Dry Matter Accumulation and Associated Changes in Biochemical Parameters during Wheat Grain Development

Field experiments were conducted in Rajkot, Gujarat, India comparing three cultivars of wheat, viz. Raj-1555, Lok-1 and Sonera, all differing in their grain yield. Apical grain of the seventh spikelet from the main spike was selected as a representative grain in each cultivar and analyzed at 4-day intervals from anthesis to maturity for dry matter, starch, sugars and protein content. The data for dry matter accumulation and starch content were fitted to a quadratic polynomial exponential which revealed a close correspondence between these two parameters. The absolute rates of starch and dry matter accumulation were highest in Lok-1 followed by Sonera and Raj-1555, respectively; however, the duration of the grain-filling observed from these curves was highest in Raj-1555. The maximum weight of the grain at harvest was in Lok-1 (80 mg) followed by Raj-1555 (71 mg) and Sonera (50 mg), respectively. Increase in the starch content coincided well with dry matter accumulation. Reducing and nonreducing sugars were high during early stage but declined with advances in growth up to almost middle of the grain growth; high levels were even found at later stages. Although protein increased with increasing grain growth in Raj-1555 and Sonera, no clear trend was observed in Lok-1 in relation to dry matter accumulation. The results are discussed in relation to the use of polynomial functions and the contribution of photosynthate supply from various plant parts in relation to grain growth and yield in wheat.     

灌浆期高温对小麦籽粒淀粉的积累、粒度分布及相关酶活性的影响

以不同耐热性品种济麦20和鲁麦21为材料, 于花后5~9 d进行高温处理, 研究了小麦灌浆期高温对籽粒淀粉的积累、粒度分布及合成相关酶活性的影响。结果表明, 灌浆期高温显著降低籽粒淀粉积累量, 显著降低籽粒淀粉、支链淀粉含量, 提高直链淀粉含量和直/支链淀粉比例。高温对济麦20籽粒淀粉积累的影响程度较鲁麦21大。灌浆期高温使小麦籽粒A型淀粉粒的体积、数量和表面积百分比显著增加, B型淀粉粒这3指标则显著降低。高温处理后, 济麦20籽粒蔗糖合酶(SS)、ADPG焦磷酸化酶(AGPP)、可溶性淀粉合酶(SSS)、束缚态淀粉合酶(GBSS)活性与对照无显著差异, 而鲁麦21上述酶活性则高于对照。济麦20、鲁麦21籽粒上述酶活性分别于花后15 d和20 d开始低于对照。与其他淀粉合成相关酶相比, 高温对籽粒GBSS活性的影响程度较小。两品种处理间籽粒蔗糖含量及SS、AGPP、SSS和GBSS活性的变化趋势, 与其籽粒淀粉积累量的变化趋势基本一致。灌浆期高温使籽粒淀粉积累量降低, 主要因高温抑制了籽粒灌浆中后期的淀粉合成, 这是由籽粒蔗糖供应不足和籽粒淀粉合成相关酶活性下降所造成的。     

An Analysis of Grain Development in Oryza sativa L. Cultivars

A field study was conducted to determine if differences in grain filling rate and duration existed in two early cultivars of rice. There is no cultivar difference in duration of grain filling and grain matured in about 30 days from anthesis in both the cultivars. The effective grain filling period in rice is only 10 days between 3rd and 13th day from anthesis. There is significant difference in grain filling rate and is positively related to grain weight. Grain filling rate is more important than duration of filling for achieving higher grain size and thus yield in rice.     

Effects of Post-Anthesis Drought and Waterlogging on Accumulation of High-Molecular-Weight Glutenin Subunits and Glutenin Macropolymers Content in Wheat Grain

Drought and flooding during grain filling have become major constraints to wheat quality and yield. The impacts of water deficits and waterlogging during the grain filling on contents of high-molecular-weight glutenin subunits (HMW-GS) and of glutenin macropolymers (GMP) in grains of the winter wheat cultivar Yumai 34 with high grain protein content (GPC) and Yangmai 9 with low GPC were studied. At maturity, GPC was higher under drought and lower under waterlogging compared to the control, while contents of GMP and HMW-GS were reduced by the two water-stress treatments. The contents of both HMW-GS and GMP were higher in Yumai 34 than in Yangmai 9. A drought event after anthesis increased the accumulation of HMW-GS during the early grain filling stage. By contrast, waterlogging reduced the accumulation of HMW-GS during the whole grain filling phase. At maturity, the HMW-GS and GMP to protein ratios were also depressed under the two water-stress events, while the HMW-GS to GMP ratio was very close between the three treatments in Yumai 34 and much higher under the control than the drought and waterlogging treaments in Yangmai 9. It is concluded that the variation in GMP content with various water-stress treatments is attributed to the changing in accumulation of HMW-GS in the grain.