不同施肥水平对沈甜6号产量和生理指标的影响

在密度为57000株/hm~2的春播条件下对沈甜6号玉米品种进行5个施肥量试验.结果表明,在施用N 187.5 kg/hm~2、P_2O_5 75.0 kg/hm~2,K_2O 97.5 kg/hm~2时产量最高,可产鲜穗13437.0 kg/hm~2,叶面积指数达到2.78,品质和各项生理指标处于较高水平.当施肥量超过N 225.0 kg/hm~2 P_2O_5 90.0 kg/hm~2、K_2O 117.0 kg/hm~2时产量下降,茎秆含糖量和叶面积指数下降.     

辽宁省玉米化肥施用现状及存在问题与建议

对辽宁省14个市309个玉米田块化肥投入情况进行调查,分析玉米化肥施用中存在的主要问题。结果表明,辽宁省玉米平均产量为8 121 kg/hm~2,化肥养分(N、P_2O_5、K_2O)总施用量为312～479 kg/hm~2。氮(N)肥投入区间为188～275 kg/hm~2,磷(P_2O_5)肥投入区间为88～144 kg/hm~2,钾(K_2O)肥投入区间为64～119 kg/hm~2,N、P_2O_5、K_2O的平均投入比例为1∶0.48∶0.37,N、P_2O_5、K_2O平均偏生产力为36、75、96 kg/kg。根据辽宁省推荐施肥标准,全省平均氮、磷的减施潜力分别为53 kg/hm~2(23%)和30 kg/hm~2(28%)。辽宁省施用中微量肥料和有机肥极少、长效肥料较少,肥料以一次性施用为主。建议降低氮、磷肥施用量,增加钾肥用量,调整施肥比例,增加缓释长效肥料的施用,有条件的区域增加追肥次数。     

施肥量对甜菜产量和生理指标的影响

试验结果表明,为获得2.8～3.0t/亩块根产量,亩施肥量以N8kg、p_2O_59.6kg、K_2O8kg为宜;甜菜含糖率与施肥量呈负相关(r=-0.5484),但未达显著水平;甜菜的NAI与施肥量呈正相关(r=0.9909)。每亩N10kg、P_2O_5;12kg、K_2O10kg处理和N8kg、P_2O_59.6kg、K_2O8kg处理群体发育良好,LAI保持在3.0以上的时期长达45天以上,并有较强的净光合生产率,有利于产量形成;甜菜单株干物重与施肥量呈正相关(r=0.9600)高肥处理虽然生物产量高,但因T/R比高,叶部徒长,分配率低,而导致经济产量低。     

水肥耦合调控对水稻光合特性的影响

为探究水肥耦合调控对水稻的光合特性的影响,本研究采用淹水灌溉、节水灌溉、干旱胁迫3个灌溉模式为主因子,正交施肥处理作为副因子(纯N:0、69、138 kg/hm~2;P_2O_5:0、33.6、67.2 kg/hm~2;K_2O:0、54、108 kg/hm~2),于分蘖期、抽穗期、成熟期测定叶绿素含量,于灌浆期测定剑叶光合参数。研究表明,同一灌溉模式,施肥对叶绿素含量、光合速率、气孔导度影响程度不同,且均显著高于对照(p0.05),与施肥量呈正相关,N_2P_2K_0或N_2P_1K_1最大;水分补偿效应在肥料空白组最明显,同时肥料充足补加水分也能显著提高叶绿素含量、光合速率、气孔导度等光合参数。产量结果表明,产量随施肥量的增加而增加,节水灌溉下N_2P_2K_0和N_2P_1K_1产量最高。因此,干旱胁迫水稻光合作用最弱,节水灌溉和淹水灌溉光合作用强差异小,但节水灌溉较淹水灌溉耗水少,则最佳灌溉方式为节水灌溉、施肥组合为N_2P_1K_1。     

定量氮磷肥条件下钾肥不同施用量对地膜马铃薯产量、干物质与淀粉含量的影响

以马铃薯‘荷兰15’一级良种为试验材料,探讨了定量氮磷肥条件下钾肥5种不同施用量对马铃薯‘荷兰15’的产量、干物质和淀粉含量的影响。结果表明,增加钾肥(K_2O)施用量,在一定程度上可以降低小薯产量,提高总产量、商品薯产量、干物质含量、淀粉含量及经济效益。钾肥(K_2O)施用量240 kg/hm~2的总产量为38 828 kg/hm~2、商品薯产量33 315 kg/hm~2、小薯产量5 513 kg/hm~2、干物质含量210 g/kg、淀粉含量139.4 g/kg。经济效益12 910元/hm~2,高于不施钾肥、钾肥(K_2O)施用量60,120和180 kg/hm~2的处理。综合考虑,种植马铃薯‘荷兰15’,钾肥(K_2O)施用量240 kg/hm~2最适宜。     

旱地亚麻肥料效应及适宜施肥量研究

亚麻是北方旱区重要的油料作物。论文采用"3414"试验设计,研究了旱地亚麻N、P、K肥效应及适宜的肥料用量。结果表明,N、P、K配合施用显著提高了亚麻产量,三因素增产大小顺序为NPK;在该试验条件下,N、P_2O_5、K_2O用量分别为45.00、33.75、37.50 kg/hm~2时,N、P、K肥利用率最大,分别为8.38、11.85、14.93 kg/kg。一元二次肥料效应模型模拟结果显示,旱地亚麻N、P_2O_5和K_2O适宜施用量分别为41.85、82.95、37.50 kg/hm~2。     

华南春大豆氮磷钾肥配施效应及用量研究

为探明华南春大豆生产的适宜施肥量,采用"3414"肥效试验设计,选用桂春豆106开展了氮磷钾肥配施效应和推荐施肥量研究。结果表明:氮、磷、钾肥料配施可明显提高华南春大豆产量,各肥料因素对大豆产量的增产效应依次为磷氮钾,氮、磷、钾三因素之间存在互作效应,效应大小依次为氮磷磷钾氮钾;经模型最优分析表明采用三元肥效函数模型做出施肥决策是合理可行的,经回归模型的拟合得出推荐施肥量,达到最高产量时氮(N)、磷(P_2O_5)和钾(K_2O)的施肥量分别为80.6,21.6和58.4 kg·hm~(-2),达到最佳经济产量时氮(N)、磷(P_2O_5)、钾(K_2O)的施肥量分别为75.5,21.3和54.1 kg·hm~(-2)。这些研究结果将为华南地区春大豆合理施肥提供指导,为下一步建立施肥指标体系提供依据。     

粳稻品种武育粳33营养特性与肥料效应研究

通过田间试验,研究了粳稻武育粳33的营养特性、需肥规律与肥料效应。结果表明,在生育前期,武育粳33对氮、磷的需求量大,中后期增加了对钾素的吸收;氮对其产量构成因子的影响要显著高于磷和钾;结合模拟的最佳施肥量和其经济施肥量,鄂北地区中等肥力条件下武育粳33的推荐施肥量为N 240~280 kg/hm~2、P_2O_580~100kg/hm~2、K_2O 90~135 kg/hm~2。     

洞庭湖滨植棉区棉花配方施肥优化试验初探

通过开展油后直播棉花"3414"田间试验,并进行回归分析,综合得出洞庭湖植棉区籽棉目标产量3090kg·hm~(-2),N、P、K养分最佳施用量(公顷用量)为N∶P_2O_5∶K_2O=210∶60∶180,即尿素450kg、过磷酸钙495kg、氯化钾300kg。     

氮钾固定配施下施磷量对小麦光合、干物质转运及产量形成的影响

为优化氮钾固定配施下小麦适宜的磷肥施用量,以郑麦7698为试验材料进行田间小区定位试验,在4个不同的氮钾配施方式[低氮低钾(N1K1,N 225 kg·hm~(-2)+K_2O 150 kg·hm~(-2))、低氮高钾(N1K2,N 225 kg·hm~(-2)+K_2O 225 kg·hm~(-2))、高氮低钾(N2K1,N 300 kg·hm~(-2)+K_2O 150 kg·hm~(-2))、高氮高钾(N2K2,N 300 kg·hm~(-2)+K_2O 225 kg·hm~(-2))]下,设置0、150、225、300和375 kg·hm~(-2) 5个施磷(P_2O_5)水平(分别用P0～P4表示),研究不同氮钾固定配施下施磷量对小麦光合、干物质转运及产量的影响。结果表明,同一氮钾营养条件下,随施磷量的变化,小麦干物质转运、SPAD值、P_n及产量等指标的变化趋势基本一致,均表现为一定施磷范围(P_2O_50～225 kg·hm~(-2))内,随施磷量的增加,小麦花后同化物数量及其对籽粒产量的贡献率、SPAD值、P_n及产量均不同程度增加,当磷用量(P_2O_5)超过225 kg·hm~(-2)时,各指标又呈下降趋势,且均以P2处理最大。低氮低钾(N1K1)条件下各指标测定结果均较好。小麦籽粒产量与施磷量的关系呈抛物线型,二者极显著相关,施磷量在219.36～224.66 kg·hm~(-2)时小麦籽粒产量最高。综上所述,4个不同的氮钾营养条件下,以N 225 kg·hm~(-2)+P_2O_5 225 kg·hm~(-2)+K_2O 150kg·hm~(-2)(N1K1P2)配施组合最好。     

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.