杂交水稻制种花时不遇的生态生理机制研究Ⅰ花时同步指数研究

在研究杂交水稻制种父母本逐时开花动态特征的基础上，讨论了以午前花率和父母本颖花相遇率来评价花时同步程度的局限性，提出了评价父母本花时同步程度的新标准——花时同步指数，并给出了其数学表达式和计算方法，为开花习性的研究提供了理论依据。     

滑动平均法在泗优9083制种中的应用

通过对泗优９０８３的母本泗稻８号Ａ与父本Ｃ９０８３的分期播种，用滑动平均的方法制成父母本的生育期用表，可供制种应用。     

Effects of feedbacks and seed rain on ecotone patterns

Ecotones can be abrupt changes in vegetation on gradual abiotic gradients, such as some treelines, and so have been considered as potential indicators of response to climatic change and regulators of fluxes across landscapes. Factors of positive feedback for growth and establishment and seed rain from source areas have been suggested as playing a role in such patterns and dynamics. The effects of variation in feedback strength and seed rain on the abrupt pattern have not, however, been assessed. A spatially explicit computer simulation is used to represent an ecotone as might occur at a mountain treeline. The steepness of the abiotic gradient determines the general location of the treeline, while the strength of feedback determines how abrupt it is. Increased seed rain and seedling survival modify the dominant patterns by creating patches of krummholz or small seedings. The feedbacks are spatially autocorrelated and so create waves of mortality and regeneration on the simulated slopes comparable to dynamics observed on some mountains. These dynamics may mean that the pattern at the ecotone at any point in time is ephemeral and may respond differently to environmental change.     

老化处理对几种牧草种子乙烯释放量的影响

探讨了不同老化处理对紫花苜蓿、光叶紫花苕、老芒麦和苏丹草种子萌发过程中乙烯释放量的影响 ,及乙烯释放量和发芽率的关系。结果表明 :35℃高温、10 %种子含水量条件下 ,不同贮藏时间的老化处理对 4种牧草种子乙烯释放量有显著影响 ,所有供试种随种子劣变 ,乙烯释放量下降 ,且释放高峰推迟。在测定期内 (2 2 h) 2种豆科牧草种子乙烯释放量和高峰出现的时间分别高于和早于 2种禾本科牧草 ;未处理种样平均每百粒种子乙烯释放总量 ,按供试种样计算为光叶紫花苕 (56 .0 nl) >紫花苜蓿 (2 0 .0 nl) >苏丹草 (17.4 nl) >老芒麦(10 .7nl) ,而按发芽种子计算为光叶紫花苕 (6 7.5nl) >紫花苜蓿 (2 5.8nl) >老芒麦(2 2 .3nl) >苏丹草 (2 0 .2 nl)。 4种牧草种子乙烯释放量与发芽率呈极显著的正相关 (p<0 .0 5) ,其决定系数 (r2 )从高自低依次为紫花苜蓿 0 .980、光叶紫花苕 0 .96 0、老芒麦 0 .952和苏丹草 0 .94 1。     

马铃薯全息胚定域播种研究

马铃薯块茎是枝的变态 ,是营养生长型全息胚 ,不同部位其生理学机能不同。通过对薯块不同生理部位划分切割 ,进行种植观察 ,经统计分析认为 :块茎上不同的芽种植后植株性状、产量有显著差异 ,即存在着严密的全息生物学原理     

陆地棉种子物理性状的发育遗传研究

应用包含基因型×环境互作的二倍体种子遗传模型及非条件和条件的分析方法对子指、仁指、种仁率及种子容重的双列杂交两年数据进行发育遗传研究。结果表明 ,4个性状在各个时期均存在显著的直接、细胞质和母体方差 ,并以母体方差较大。条件遗传分析发现 ,在某些无法检测到非条件遗传方差的时期存在显著水平的条件方差。同一性状不同时期的相关分析表明 ,子指、仁指和种仁率在大部分时期存在显著的母体加性和母体显性相关。但种子容重各个发育阶段之间的母体相关系数几乎均为零。成对性状之间的相关研究表明 :种子容重和其它三个性状之间的大部分相关系数不显著 ;各成对性状在各时期存在显著的母体加性相关 ;性状间的相关程度及相关性质随着发育进程的改变而呈动态变化 ;性状最终时刻的相关表现无法完全体现在整个发育过程中的动态变化。     

Use of regrowth for forage in crops of timothy (Phleum pratense L.) cv. Grindstad grown for seed in Norway

Six experiments were carried out in two climatically different regions in south‐east Norway in order to compare different procedures for autumn management and use of regrowth in seed crops of timothy (Phleum pratense L.) cv. Grindstad. The experiments were laid out after seed harvest in mid‐August in crops with a stubble height of 5 cm (two experiments) or 12–15 cm (four experiments). Cutting to 5 cm on 15 September or 15 October, with or without an application of 50 kg N ha^?1 immediately after seed harvest, and with or without an additional application of 30 kg N ha^?1 after cutting, were compared with an uncut and unfertilized control treatment. As a main effect,autumn cutting increased seed yield in the subsequent year in only one experiment; this was laid out in a 13 cm stubble on a fertile soil near the coast. In the remaining five experiments seed yields were unaffected byautumn management regardless of climate or stubble height. Autumn cutting and N application increased the number of seedheads in two experiments, but this was offset by a drop in other seed yield components. On average for two cutting dates and for plots receiving an application of 50 kg N ha^?1 after seed harvest, the dry matter (DM) was 1430 kg ha^?1 on an inland site with 12–15 cm stubble, 1400 kg ha^?1 on a coastal site with 5 cm stubble and 2460 kg ha^?1 for two coastal sites with 12–15 cm stubble. Whereas forage yield and quality were fairly stable from the first to the second cut at the inland site, the yield of DM increased, but the crude protein and energy concentrations decreased from 15 September to 15 October at the coastal sites. It is concluded that the stubble and regrowth in seed crops of timothy cv. Grindstad can be harvested for forage without any effect on seed yield in the next year.     

提高旱农地区甘草田间出苗率的试验分析

通过随机区组田间试验的方法，对如何提高甘草田间出苗率进行了研究。试验证明：甘草的田间出苗率与播种深度呈负相关，若底墒好，播后不浇水，播深2．5－3．0cm，可提高其田间出苗率；若底墒差，播后浇水，播深1．5－2．0cm，亦能提高其田间出苗率。在新垦重盐碱地播种甘草，用生长素4号和1号拌种，可分别提高田间出苗率2．9倍和2．6倍。播后3d浇水比播后16d浇水的田间出苗率提高29．5％。     

高寒阴湿地区商品化草坪草种子生产技术研究

在地处高寒阴湿的漳县地区进行冷地型草坪草种子生产技术研究。结果表明:在漳县立地条件下,适合于多年生黑麦草(鳄鱼、德碧、帝王)三品种的种子生产。种植方式(移栽、条播、撒播)对种子生产能力无明显影响。其经济效益明显地优于农作物。因此,发展草坪草种子生产可做为一个新的生产机制而引入当地农牧业生产。