进口粮谷中携带杂草种子种植存活率的研究

将进口粮食中截获的杂草种子种植于隔离的自然环境中,观察自然环境下外来杂草的存活情况:在一个生长季种植的21科97种9152粒杂草种子中,有13科85种640粒种子最终存活,种类存活率达到87.6%,种子数量存活率达到7.0%;有超过一半种类的杂草种子存活率在0%~50%之间,处于中低存活水平。在此基础上,提出进口粮食的监管过程中,在严防撒漏的同时,要特别注意加强监测,尤其在杂草成熟前采取防除措施,是防止疫情扩散的关键环节。     

咸阳市建国60年来耕地利用因素与粮食生产相关分析

首先从粮食产量计算模型中解析出耕地利用4因素,即耕地利用广度、耕地利用程度、耕地利用结构以及耕地利用集约度,进而采用相关分析法求得各阶段耕地利用4因素与粮食产量的相关系数,并参考其偏相关系数,研究建国60年来耕地利用这4方面对粮食生产影响的时序变化,结果表明:(1)不断加强的耕地利用集约度始终是第一位的贡献因素,但其影响趋势缓慢减弱;(2)耕地利用广度对粮食产量的影响趋势减弱,二者互动效应不明显,然而,在耕地面积大幅度减少和农业生产技术快速发展的情况下,耕地面积对粮食生产的约束力增强;(3)耕地利用程度与粮食生产的相关性增强趋势凸显,从而,加大耕地利用程度成为推动粮食生产的有效新动力。(4)耕地利用结构变化对粮食产量的贡献减弱,然而其对粮食生产的制约性渐强。     

单粒稻米直链淀粉含量测定方法研究

单粒精米不经磨粉，直接用冷碱液在３０℃下糊化，继而煮沸测定直链淀粉含量，测得的直链淀粉含量经ｔ测验。与中华人民共和国农业部部颁标准ＮＹ１４７－８８的结果差异不显著，本法可应用于水稻直链淀粉含量的遗传分析与杂交稻米食用品质性状研究，为常规育种的后代筛选和杂交水稻的组合选配提供有效手段。     

马尾松人工林木材主要材性家系间的变异

对25个家系马尾松人工林木材主要物理力学性能进行测定和比较分析。结果表明,马尾松人工林木材气干密度由大到小居前五位的家系依次为378、329、317、341、335,顺纹抗压强度值由大到小居前5位的家系依次是335、350、372、325、329;家系341和350马尾松人工林木材体积干缩系数和差异干缩均较小,尺寸性稳定均较好。方差分析表明,家系对马尾松人工林木材主要物理力学性能影响显著。多重比较分析表明,马尾松人工林木材气干密度、体积干缩系数、差异干缩以及顺纹抗压强度各家系间大都表现为差异显著或极显著。家系335、341、350、378可作为马尾松人工林木材品质选育的优良材料。     

华南杂交晚籼高产,优质,高效组合选育实践及效果

提出华南杂交晚籼选育的８项意见，即优质性、高产性、抗病性、后期耐寒性、熟期适中性、早制晚用性、恢复系苗期耐寒性以及制种父母本播种差期短等。按此育成了博优２１０等组合，达到了预期的选盲目标。     

Agricultural Production Structure Optimization： A Case Study of Major Grain Producing Areas, China

A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance). In this study, an interval-probabilistic agricultural production structure optimization model (IPAPSOM) is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying (or risk of violating) system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.     

Can Landform Stratification Improve Our Understanding of Crop Yield Variability?

Farmers account for yield and soil variability to optimize their production under mainly economic considerations using the technology of precision farming. Therefore, understanding of the spatial variation of crop yield and crop yield development within arable fields is important for spatially variable management. Our aim was to classify landform units based on a digital elevation model, and to identify their impact on biomass development. Yield components were measured by harvesting spring barley (Hordeum vulgare, L.) in 1999, and winter rye (Secale cereale, L.) in 2000 and 2001, respectively, at 192 sampling points in a field in Saxony, Germany. The field was stratified into four landform units, i.e., shoulder, backslope, footslope and level. At each landform unit, a characteristic yield development could be observed. Spring barley grain yields were highest at the level positions with 6.7 t ha⁻¹ and approximately 0.15 t ha⁻¹ below that at shoulder and footslope positions in 1999. In 2000, winter rye harvest exhibited a reduction at backslope positions of around 0.2 t ha⁻¹ as compared to the highest yield obtained again at level positions with 11.1 t ha⁻¹. The distribution of winter rye grain yield across the different landforms was completely different in 2001 from that observed in 2000. Winter rye showed the highest yields at shoulder positions with 11.1 t ha⁻¹, followed by the level position with 0.5 t ha⁻¹ less grain yield. Different developments throughout the years were assumed to be due to soil water and meteorological conditions, as well as management history. Generally, crop yield differences of up to 0.7 t ha⁻¹ were found between landform elements with appropriate consideration of the respective seasonal weather conditions. Landform analysis proved to be helpful in explaining variation in grain yield within the field between different years.     

品种演替和土壤肥力对小麦产量和磷生理效率的影响

以25年来长期定位施肥试验构建不同土壤肥力梯度为平台,研究品种演替过程中籽粒产量和磷效率对土壤肥力的响应。结果表明,各施肥处理,随品种演替小麦籽粒产量呈显著增加趋势,其中郑麦0856的产量最高(8 157. 3kg·hm-2),郑麦7698次之,豫麦13的产量最低(5 915. 39 kg·hm-2);不施肥处理(CK)则下降。无论施肥或不施肥处理,100 kg小麦籽粒对磷素的需求量均随品种的演替呈上升趋势。此外,随品种演替,磷的生理效率呈先增加后降低的趋势,郑麦941 (172. 48 kg·kg-1)的磷生理效率最高,郑麦9023 (145. 79 kg·kg-1)、郑麦7698 (130. 51kg·kg-1)和郑麦0856 (147. 65 kg·kg-1)次之,三者之间差异不明显,豫麦13 (66. 71 kg·kg-1)的磷生理效率最低;同一品种,单施化肥处理(NPK)小麦磷生理效率显著高于其他施肥处理(MNPK、1. 5MNPK和SNPK)(豫麦13除外)。同时,品种演变明显提高了磷农学效率;但在施肥条件下,继续增施肥料和养分投入使豫麦13、郑麦941、郑麦7698和郑麦9023的磷农学效率降低;而郑麦0856的农学效率随着土壤肥力的增加而增加,与籽粒产量协同提升。因此,黄淮海地区小麦品种演替在土壤肥力养分充足时籽粒产量显著提高,磷效率也呈增加的趋势。     

含水率对稻米籽粒剪切特性的影响研究

稻米籽粒的剪切特性指标可以作为稻米品质评价的指标之一,本文通过试验获得了稻米籽粒剪切特性的力学指标包括硬度、破坏能、破坏力及破坏应力等,并研究了含水率对稻米籽粒剪切特性的影响,通过多项式回归建立了剪切特性指标与含水率之间关系的回归方程,为水稻品质育种,评定和控制水稻的最后质量提供新的方法和新的研究手段.     

含水率对稻米籽粒应力松弛特性影响的研究

稻米籽粒的松弛特性在其生产、质量控制中起着重要作用。本文通过试验获得了稻米籽粒应力松弛特性的力学指标,并研究了含水率对稻米籽粒应力松弛特性的影响,通过多项式回归分析建立了稻米籽粒应力松弛各力学指标随含水率变化关系的数学模型,为稻米加工装置的设计以及稻米的质量评价提供理论依据。