水稻品种产量性状的遗传相关及通径分析

通过对水稻品种的几个主要产量性状的遗传相关和通径分析表明，结实率、每穗实粒数、穴穗数与产量间有较高的遗传相关和通径系数。在选育水稻新品种中，应在稳定千粒重和较高结实率的基础上，把穗实粒数和穴穗数作为重点选择指标，可望选育出高产水稻品种。     

辽宁省主栽水稻品种高产群体形成规律研究

为构建东北平原南部水稻高产群体,揭示其产量形成规律,以辽宁省主栽高产水稻品种辽粳401和辽粳212为试材,进行了不同栽培密度试验。结果表明,高密度处理（行株距20.0 cm×13.3 cm）单位面积有效穗数显著增加,从而获得较高的产量水平,但与低密度处理（行株距30.0 cm×20.0 cm）的产量差异不显著。在低密度处理下,虽然有效穗数少,但每穗粒数增加,因此也具有相对较高的产量水平。高密度行株距配置可构建依靠增加群体分蘖数量和较多物质积累而获得高产的多穗型群体,低密度行株距配置可构建促进物质转移转化、提高收获指数形成大穗大粒而获得高产的大粒型群体。可见,通过平衡有效穗数和穗粒数二者之间的关系,保证群体颖花量,同时确保较高的结实率和千粒重,可获得稳定高产群体。     

水稻喷施不同元素叶面肥对产量的影响

叶面肥是营养元素施用于农作物叶片表面,通过叶片的吸收而发挥基本功能的一种肥料。本试验通过对水稻分别喷施复旦复农、大田园、农都乐三种叶面肥进行对比,试验结果表明：水稻喷施叶面肥可以增加水稻穗粒数,提高结实率和千粒重,并且能降低病虫害的发病几率,从而达到增产增收目的。     

大穗型水稻品种穗部结构特征分析

大穗型水稻存在严重的结实率较低和不稳定的问题,从水稻穗部结构探讨大穗型水稻品种结实差异,有利于揭示大穗型水稻结实障碍产生的原因.本研究选用中国目前在生产和育种上广泛使用的大穗型品种及部分已稳定遗传的大穗型材料共32份,调查其在大田条件下的穗部结构、结实特性及其相互关系.结果表明:大穗籼型或籼-籼(粳)组合水稻的结实率总体上主要取决于其2次枝梗的结实率.根据各品种1次枝梗数与2次枝梗数的比值(BI)和结实率对所有供试材料进行聚类分析,将供试品种分成3类:第Ⅰ类BI=0.18～0.40,结实率≧85％,可定义为2次枝梗高结实率型;第Ⅱ类BI=0.18～0.36,结实率≦83％,定义为2次枝梗低结实率型;第Ⅲ类仅有BL006,BI=1.15,结实率为92％,定义为1次枝梗高结实率型.第Ⅰ类和第Ⅲ类在结实性能上具有优势和潜力.     

粳稻穗部性状分析及与米质的关系

以辽宁省2005年区域试验部分水稻新品系为试材,对其穗部性状进行了分类及相关分析。结果表明,高产品种应具有较多的一次、二次枝梗数目、粒数和较高的二次枝梗数结实率,同时分析了穗部性状与米质的关系,探讨通过穗部性状选择提高产量和改善水稻品质的途径。     

辽宁省部分中熟水稻品种穗部性状与结实特性分析

以辽宁省最新育成的水稻品种(品系)为试材,把参试品种分为高产品种、中产品种和低产品种三类,分析了不同产量水平水稻品种穗部性状及其结实特性,结果表明,高产品种具有较高的每穗粒数、二次枝梗粒数、一次枝梗粒数、以及较高的二次枝梗粒率,具有较高的结实率、二次枝梗结实率、一次枝梗结实率,具有较高的一次枝梗数、二次枝梗数,使穗粒结构得到较大程度的协调,以致其产量处于较高的水平。     

粳稻穗部性状分析及与米质的关系

以辽宁省2005年区域试验部分水稻新品系为试材，对其穗部性状进行了分类厦相关分析。结果表明，高产品种应具有较多的一次、二次枝梗数目、粒数和较高的二次枝梗数结实率。同时分析了穗部性状与米质的关系，探讨通过穗部性状选择提高产量和改善水稻品质的途径。     

水稻高产优质的数学模型分析

通过对水稻高产栽培的三元回归分析,明确了嫩江灌区水稻的穴穗数、穗粒数和千粒重之间的数量关系,并指出提高千粒重是增加水稻单产的关键环节。同时,提出了配套的技术措施。     

减数分裂期高温对水稻穗粒数影响的定量分析

【目的】穗粒数是水稻产量构成因子之一。为明确减数分裂期高温对水稻穗粒数的可能影响,构建其定量估算模型,【方法】于2014-2015年以两优培九和南粳45为供试材料,于减数分裂期设置不同强度和持续时间的高温处理,以自然无高温环境为对照,分析了减数分裂期不同高温强度和高温持续时间对穗粒数的影响,建立了减数分裂期高温与穗粒数的定量关系,最后根据温度日变化特征,构建了自然环境下的减数分裂期高温对穗粒数的定量影响算法。【结果】减数分裂期高温对穗粒数的影响程度与高温强度、持续时间有关。同样高温条件下,穗粒数随高温持续天数增加呈指数减少;日相对穗粒数随温度增加而减少,可用二次曲线进行描述。穗粒数对高温敏感的终止时间大约为抽穗前5 d。利用2015年试验资料对上述模型进行了检验,两优培九和南粳45穗粒数模拟值的相对均方根差为0.094和0.085,说明模型可很好地模拟减数期高温对穗粒数的影响。【结论】对完善高温对水稻生长过程的定量影响具有重要作用。     

寒地早粳稻穗部性状与产量关系的研究

针对寒地特殊的生态环境,以180份不同基因型早粳稻为材料,较系统地探讨了穗部性状与产量的关系。研究表明,在保证一定穗长的基础上,追求较大的单穗重而且结实良好是超高产育种的主攻方向。着粒密度高是不利于产量提高的,而较高的每穗实粒数,即良好的结实率是获得高产的主要途径。产量与一次枝梗数、二次枝梗数、二次枝梗数／一次枝梗数呈极显著负相关,说明保证一定的一次枝梗数,在一定范围内减少每穗的二次枝梗数是提高产量的最有效途径。产量与一次枝梗实粒数、一次枝梗结实率、二次枝梗结实率呈极显著的正相关,提高一、二次枝梗的结实率,尤其是提高一次枝梗结实率是寒地水稻超高产育种穗部性状选择的最佳途径。     

Factors in the Reduction in Grain Number in Winter Wheat by Early-Sowing in Yamaguchi

Abstract

Grain number per spike of wheat is lower in early sowing than in the conventional standard cultivation in Yamaguchi, Prefecture, Japan. Components of the grain number per spike in five cultivars were analyzed with respect to temperature during the spike development period throughout three growing seasons 2001/2002, 2002/2003 and 2003/2004 to find the cause of the problem of early sowing cultivation. The plants sown in early-October and late-November were called the early sown group and the standard group, respectively, in the following. Three of the five cultivars, Hokushin, Akitakko and Nanbukomugi, showed a strong winter habit, which requires very cold temperatures for spike differentiation. The other two cultivars, Iwainodaichi and Airakomugi, had a moderate winter habit. Grain number per spike and grain yield were decreased by early-sowing (compare with the standard group) in almost all cultivars throughout the three growing seasons. The three cultivars which had a strong winter habit had fewer spikelets per spike in the early-sown group than in the standard group. The other two cultivars which had a moderate winter habit had fewer grains per spikelet in the early-sown group. The higher the temperature during the spikelet formation phase, which is from flag leaf initiation to terminal spikelet initiation, the higher the number of spikelets per spike in the standard group. The spikelet number per spike in the early-sown group increased with the increase in productive tillers under fertile conditions. Such conditions also increased the grain number per spike.     

Allelopathy in Agroecosystems in Spain

Summary

This paper reviews the effects of allelopathic interactions in agroecosystems in Spain on plant physiological activity and their ecological advantages. The phenological stage of growth of donor plants and the effective allelochemicals in the soil solution while studying the role of phenolic compounds were highlighting. Finally possible future prospects and conclusions regarding weed control by allelochemi-cals under integrated crop management strategies are discussed.     

2009年中国稻米市场分析及2010年展望

以翔实的资料对2009年中国稻米生产、消费、进出口、供求平衡、库存、价格走势、购销政策和国际稻米供求等情况进行了全面地分析,对影响2010年稻米市场价格走势的各种因素进行了深入研究,并在此基础上对2010年我国稻米市场价格走势进行了预测,结论是我国稻米价格仍呈上行趋势。     

Advances in Variable Rate Technology Application in Potato in The Netherlands

Precision agriculture is a farming management concept based on observing, measuring and responding to inter- and intra-field variability in crops. In this paper, we focus on responding to intra-field variability in potato crops and analyse variable rate applications (VRAs). We made an overview of potential VRAs in potato crop management in The Netherlands. We identified 13 potential VRAs in potato, ranging from soil tillage to planting to crop care to selective harvest. We ranked them on availability of ‘proof of concept’ and on-farm test results. For five VRAs, we found test results allowing to make a cost-benefit assessment. These five VRAs were as follows: planting, soil herbicide weed control, N side dress, late blight control and haulm killing. They use one of two types of spatial data: soil maps or biomass index maps. Data on costs and savings of the VRAs showed that the investments in VRAs will pay off under practical conditions in The Netherlands. Savings on pesticide use and N-fertilizer use with the VRAs were on average about 25%, which benefits the environment too. We foresee a slow but gradual adoption of VRAs in potato production. More VRAs will become available given ongoing R&D. The perspectives of VRAs in potatoes are discussed.     

我国高粱育种研究进展

对我国高粱育种的主要途径和研究方向进行了概述,针对目前高粱产量徘徊现象,提出了高粱超高产育种设想,并对其技术路线进行了探讨。     

Diurnal changes in net photosynthetic rate in potato in two environments

Summary Diurnal changes in net photosynthetic rate were measured in a furrow-irrigated potato crop and in a riverbed crop where the water table was always maintained at 20–28 cm from the soil surface. In the irrigated crop, the photosynthetic rate during mid-afternoon was about half the peak rate observed at noon. This reduction was accompanied by a near tripling of stomatal resistance, a 45% reduction in transpiration, and a 5-fold increase in the difference between leaf and air temperatures. No such changes were observed in the riverbed crop where the photosynthetic rate remained nearly constant at about 0.9 mg m⁻² s⁻¹ between 9 a.m. and 4 p.m. Tuber yield in the riverbed crop was about 30% higher than in the irrigated crop.     

我国干热区甘蔗抗旱植蔗主要问题研讨

我国干热蔗区是我国甘蔗糖业的重要生产基地,蔗区光热资源丰富,唯降水分布不均成为植蔗生产的主要限制因子;根据蔗区植蔗特点和甘蔗需水规律,苗期抗旱是干热蔗区抗旱植蔗的关键,保证较多的总苗数和足够的生长量是苗期抗旱植蔗需解决的关键技术难题,制定相应的苗期抗旱植蔗栽培技术措施是解决该难题的重要保障;该观点为我国干热蔗区植蔗生产、甘蔗引育种提供理论和技术支持。     

棉花体细胞无性系变异的研究进展

体细胞无性系变异是一种重要的细胞工程育种技术,其应用于棉花育种的前提是建立高效的组织培养诱导再生植株体系.本文简要综述了棉花离体诱导植株再生研究的现状,重点讨论了棉花体细胞无性系变异的表现、利用方法及机理,提出了当前研究存在的问题并对今后的研究进行了展望.