黄土旱塬粮食高产记录及其启示

研究了黄土旱塬区历史的与当今的粮食高产记录 ,结果表明 ,目前黄土旱塬各地出现的一料作物单产 15t/hm2 ,在国内其它地区也不多见。据此明确指出 ,黄土旱塬区粮食生产有巨大潜力 ,深入开展粮食高产研究必将推动粮食“高产、高质、高效”的全面发展 ,还将促进农业科学研究取得长足进步以至突破性发展 ,创建粮食高产还可成为治理水土流失与改善生态环境的突破口

水肥空间组合对冬小麦光合特性及产量的影响

以肥熟土垫旱耕人为土为供试土壤,用分层土柱试验法研究了不同土层水分、氮、磷空间组合对冬小麦不同生育时期光合特性及籽粒产量的影响.结果表明:与0～90cm土层整体湿润相比,上干下湿(0～30cm土层干旱胁迫,30～90cm土层湿润)水分处理显著降低了小麦叶片叶绿素相对含量(SPAD)、净光合速率(Pn)和籽粒产量.2种水分条件下,氮磷配施处理对叶片SPAD、Pn和小麦籽粒产量的影响最为显著,其次是施磷处理,而施氮处理影响不显著.不同土层施氮在2种水分条件下各指标的变化趋势相同,均表现为0～90cm土层施氮小麦叶片SPAD、Pn及籽粒产量显著高于0～30、30～60和60～90cm土层施氮.不同土层施磷在2种水分条件下各指标的变化趋势也相同,表现为0～90cm土层施磷小麦叶片SPAD、Pn和籽粒产量与0～30cm土层施磷间差异不显著.不同土层氮磷配施在2种水分处理下表现不同:整体湿润条件下0～90cm土层施肥处理的小麦叶片SPAD、Pn及籽粒产量最高,与0～30cm土层差异不显著,但二者均显著高于30～60和60～90cm土层处理;上干下湿条件下各土层施肥处理间小麦叶片SPAD差异不显著,0～90cm土层施肥处理...

土壤改良剂节水增产效应的田间试验研究

采用田间试验,探讨了施用土壤改良剂对冬小麦的产量及水肥利用效率的影响。结果表明,施加土壤改良剂能降低作物生育期耗水量,提高冬小麦的产量,增加水肥利用效率。在不灌水条件下,施加土壤改良剂1500kg/hm2,能够使冬小麦较对照增产15%,水分利用效率(WUE)提高了21.65%,磷肥利用效率(PUE)较单施磷肥增加2.92%。在灌水33.3mm的条件下,施加土壤改良剂较对照可增产28.57%,将土壤改良剂与磷肥混施增产可达到42.86%。而且,PUE较单施磷肥增加了11.11%,WUE达到25.06kg/(hm2·mm)。

半湿润农田杂草及施氮对夏玉米产量及氮素利用的影响

以土垫旱耕人为土为供试土壤,采用大田试验,研究了半湿润农田两种杂草处理方式下(成熟后期清除杂草-A区和苗期开始清除杂草-B区),不同施氮量对夏玉米产量及氮素利用效率的影响。结果表明,当施氮量为0、45、90、1351、80 kg/hm2时,B区玉米子粒产量比A区分别增加了8.7%、12.1%、9.4%、5.0%和12.5%;吸氮量分别增加了1.5、2.9、4.85、.2和4.3 kg/hm2。A区和B区全生育期0—100 cm土层矿质氮(Nmin)累积量变化趋势基本一致,但B区比A区变幅较大。当施氮量为45、90、135和180 kg/hm2时,B区氮肥利用率、氮肥农学利用率、氮肥生理利用率均高于A区。研究还发现,在A区,当施氮量为180 kg/hm2时,杂草干生物量最大,为1518.3 kg/hm2,不施氮时,杂草的生物量最低,为845.7 kg/hm2;杂草的吸氮量随施氮量的增加而增加。可见,清除玉米农田杂草不仅可以提高作物产量和氮肥利用率,而且在减少氮素损失方面具有一定作用。

不同施氮水平和杂草清除时间对半湿润地区农田氮素利用及产量的影响

在半湿润地区中等肥力土垫旱耕人为土上进行田间试验,通过对冬小麦不同生育期杂草和作物样品的采集与分析,研究不同施肥及杂草处理对氮肥肥效的影响。结果表明:作物吸氮量随施氮量增加而增加,杂草吸氮量随吸氮量增加而降低;在不同杂草处理全生育期不清除杂草(A)、越冬前清除杂草(B)、返青期清除杂草(C)和拔节期清除杂草(D)的各个处理中,A、B、C和D杂草吸氮量分别占农田植物(作物+杂草)地上部分总吸氮量的1.98%、1.39%、3.99%和3.82%。籽粒产量随施氮量增加而增加,施氮量为135 kg N.hm-2时产量最高,达5 645.1 kg.hm-2,施氮量高于135 kg N.hm-2时,产量趋于稳定。氮肥利用率、氮肥利用效率、氮肥农学效率和氮肥生理效率均随施氮量增加而降低;从不同杂草处理看,以全生育期不清除杂草处理氮肥利用率最高,达到43.8%,返青期清除杂草处理氮肥利用率最低,为26.3%,二者间差异达显著水平;氮肥利用效率以越冬期清除杂草处理最高,为42.8 kg.kg-1N,全生育期不清除杂草处理最低,为40.6kg.kg-1N;氮肥生理效率以返青期清除杂草处理最高,为57.5 kg.kg-1N,显著高...

黄土塬区旱作冬小麦增产潜力研究

在长期冬小麦潜势试验和肥料试验的基础上 ,建立了作物光温水肥产量模型 ,从光温生产潜力、旱作产量潜势、现阶段施肥水平下光温水肥产量潜力和目前试区产量现状共4个层次 ,对黄土塬区旱作冬小麦的增产潜力进行了分析。结果指出 ,目前黄土塬区冬小麦实际产量仅达到了光温潜力的41 6 %、旱作产量潜势的49 3 %、试区施肥水平下光温水肥产量潜力的78 6 %。因此 ,采用合理施肥方式和加强田间管理 ,黄土高原塬区旱作冬小麦还有较大的增产潜力。

黄土高原水土流失区粮食现状与增产潜力研究

以黄土高原10个试区的攻关资料为基础 ,从区域旱作产量潜势、试区攻关水平和试区所在县的产量现状三个层次 ,详细剖析了黄土高原水土流失区粮食现状和增产潜力。结果指出 ,该区粮食增产潜力很大 ,目前整体产量水平仅达到试区攻关水平的74.7 % ,达到旱作粮食产量潜势水平的54.2 %。在黄土台塬区和丘陵区中 ,丘陵区的粮食增产潜力较台塬区大 ,前者尚有117.6 %增产能力 ,后者仅56.6%。但考虑到人口增长和坡耕地的退垦等因素 ,未来30年内黄土高原水土流失区的粮食供需仍处于负平衡。

不同生育期干旱对冬小麦产量及水分利用效率的影响

用盆栽对冬小麦不同生育阶段进行不同程度水分调亏试验结果表明 :拔节—孕穗期、抽穗—扬花期和灌浆—成熟 3个阶段内 RW上限为 4 0 %、5 0 %、60 %的水分亏缺均引起了产量的极显著下降 ,而且水分亏缺越严重 ,产量降低越大。在 3个生育阶段内进行 RW上限为 4 0 %的水分调亏减产幅度都很大 ,而且 3个生育阶段之间差异不明显 ;进行 5 0 %、60 %水分调亏 ,其减产程度则与生育期有关。灌浆—成熟期的减产程度大于前二个时期 ,这可能与前二个阶段复水后作物的补偿生长有关。不同生育期水分亏缺对冬小麦产量构成因素的影响也不同 ,拔节—扬花期水分亏缺主要减少了穗粒数 ,灌浆—成熟阶段的水分亏缺主要减少了千粒重

栽培模式、施氮和品种对冬小麦冠层结构和产量的影响

在黄土高原南部半湿润易旱区土垫旱耕人为土上进行大田试验,研究氮肥、品种和栽培模式对冬小麦叶面积指数(LAI)和透光率(DIFN)及产量的影响。结果表明,小麦生长过程中LAI先增大后减小,在开花期最大,成熟期最小,施氮能够显著增加LAI;DIFN的变化规律与LAI相反。不同品种间LAI和DIFN差异显著。全程覆膜和覆膜150 d的LAI极显著大于常规栽培、集雨面栽培和三密一稀栽培模式,DIFN与此相反;施氮后籽粒产量极显著增加。在不同栽培模式下,以全程覆膜、覆膜150 d和集雨面栽培模式的产量较高,但从维持土壤质量角度考虑,则覆膜150 d和集雨面2种栽培模式优于其它几种栽培模式;从冠层结构特征分析,这2种栽培模式更有利于增加群体光合能力。

栽培模式和花后去叶对小麦产量及其构成的影响

在黄土高原南部半湿润易旱区以土垫旱耕人为土为供试土壤,进行大田试验,研究了不同栽培模式下花后去叶对产量及其构成的影响。结果表明,不同栽培模式对穗粒数、千粒重和籽粒产量的影响差异显著(P<0.05),集雨面栽培下穗粒数最多;全程覆膜、覆膜150 d和集雨面栽培模式千粒重显著高于常规栽培和三密一稀栽培;全程覆膜栽培下籽粒产量最高。去叶处理对穗粒数、千粒重和籽粒产量影响差异显著(P<0.05),各去叶处理穗粒数均大于对照。不同去叶处理千粒重均小于不去叶对照。不同去叶处理籽粒产量大小顺序为去全旗叶>对照>只保留旗叶>去1/2旗叶>去旗叶、倒二叶。去叶处理对穗粒数、千粒重和籽粒产量的影响因栽培模式不同而有差异。

Analysis of arable land loss and its impact on rural sustainability in Southern Jiangsu Province of China

Rapid urbanization and industrialization in southern Jiangsu Province have consumed a huge amount of arable land. Through comparative analysis of land cover maps derived from TM images in 1990, 2000 and 2006, we identified the trend of arable land loss. It is found that most arable land is lost to urbanization and rural settlements development. Urban settlements, rural settlements, and industrial park-mine-transport land increased, respectively, by 87 997 ha (174.65%), 81 041 ha (104.52%), and 12 692 ha (397.99%) from 1990 to 2006. Most of the source (e.g., change from) land covers are rice paddy fields and dryland. These two covers contributed to newly urbanized areas by 37.12% and 73.52% during 1990-2000, and 46.39% and 38.86% during 2000-2006. However, the loss of arable land is weakly correlated with ecological service value, per capita net income of farmers, but positively with grain yield for some counties. Most areas in the study site have a low arable land depletion rate and a high potential for sustainable development. More attention should be directed at those counties that have a high depletion rate but a low potential for sustainable development. Rural settlements should be controlled and rationalized through legislative measures to achieve harmonious development between urban and rural areas, and sustainable development for rural areas with a minimal impact on the ecoenvironment. (C) 2009 Elsevier Ltd. All rights reserved.

Radiation-use efficiency and the harvest index of winter wheat at different nitrogen levels and their relationships to canopy spectral reflectance

Radiation-use efficiency (RUE, g/MJ) and the harvest index (HI, unitless) are two helpful characteristics in interpreting crop response to environmental and climatic changes. They are also increasingly important for accurate crop yield simulation, but they are affected by various environmental factors. In this study, the RUE and HI of winter wheat and their relationships to canopy spectral reflectance were investigated based on the massive field measurements of five nitrogen (N) treatments. Crop production can be separated into light interception and RUE. The results indicated that during a long period of slow growth from emergence to regreening, the effect of N on crop production mainly showed up in an increased light interception by the canopy. During the period of rapid growth from regreening to maturity, it was present in both light interception and RUE. The temporal variations of RUEAPAR (aboveground biomass produced per unit of photosynthetically active radiation absorbed by the canopy) during the period from regreening to maturity had different patterns corresponding to the N deficiency, N adequacy and N-excess conditions. Moreover, significant relationships were found between the RUEAPAR and the accumulative normalised difference vegetation index (NDVI) in the integrated season (R-2 = 0.68), between the HI and the accumulative NDVI after anthesis (R-2 = 0.89), and between the RUEgrain (ratio of grain yield to the total amount of photosynthetically active radiation absorbed by the canopy) and the accumulative NDVI of the whole season (R-2 = 0.89) and that after anthesis (R-2 = 0.94). It suggested that canopy spectral reflectance has the potential to reveal the spatial information of the RUEAPAR, HI and RUEgrain. It is hoped that this information will be useful in improving the accuracy of crop yield simulation in large areas.

Rendimento de grãos e componentes primários de rendimento de híbridos de girassol em campo novo de parecis, na segunda safra do verão de 2015.

RESUMO: O objetivo deste trabalho foi avaliar rendimento de grãos e componentes primários de rendimento de híbridos de gIrassol em Campo Novo do Parecis, na segunda safra do verão de 2015. O estudo foi realizado no campo experimental do Instituto Federal de Educação, Ciência e Tecnologia de Mato Grosso ? campus Campo Novo do Parecis, entre os meses de fevereiro e junho de 2015. Foram analisados 13 tratamentos (híbridos), em delineamento de blocos casualizados, com 4 repetições. Foram avaliadas as seguintes características: tamanho do capitulo, massa de capítulo, massa de aquênios por capítulo, índice de colheita, massa de mil aquênios e produtividade de aquênios. Os dados foram submetidos à análise de variância e ao teste de média Scott-Knott (p<0,05). O híbrido BRS G44 apresentou os melhores resultados para rendimento de grãos e seus componentes primários avaliados na segunda safra de verão de 2015, em Campo Novo do Parecis. Assim, este híbrido pode ser uma opção de cultivo na região.

Desempenho de genótipos de girassol no cerrado do leste Maranhense, ano agrícola 2013/2014.

RESUMO: No ano agrícola 2013/2014, foram conduzidos três ensaios de avaliação de genótipos de girassol, sendo dois no município de Mata Roma e um em Magalhães de Almeida, com o objetivo de identificar materiais promissores para produção de grãos e óleo. O espaçamento utilizado foi de 0,70 m entre linhas com plantas distanciadas de 0,30 m. A adubação de fundação constou de 200 kg ha-1 da fórmula 05-30-15 + micronutrientes e cobertura aos 30 dias após semeadura, usando-se 30 kg ha-1 de N e 30 kg ha-1 de K2O. Em Mata Roma, a produtividade de grãos no ensaio final 01 variou de 1.866 kg ha-1 a 2.567 kg ha-1, obtida nos genótipos Embrapa 122 e BRS G34, respectivamente, ficando a média geral do ensaio em 2.095 kg ha-1. No ensaio final 02 a produtividade de grãos variou de 1.705 kg ha-1 a 2.036 kg ha -1 para os genótipos Helio 250 e MG 360, REspectivamente, com média geral de 1.834 kg ha-1. Em Magalhães de Almeida a produtividade de grãos obtida no ensaio final constou de 1.600 kg ha-1 no genótipo Helio 251, 2.110 kg ha-1 no CF 101 e média Geral do ensaio de 1.908 kg ha -1. Os maiores teores de óleo obtidos nos três ensaios foram 40,1%, 40,6%, 40,9% e 41,4%, respectivamente, nos genótipos CF 101, Paraíso 20, BRS G41 e MG 360. ABSTRACT: In the agricultural year 2013/2014, three sunflowers genotypes tests were conducted in the state of Maranhão: two in the county of Mata Roma and one in Magalhães de Almeida, in order to identify promising materials for the production of grain and oil. The spacing used was 0.70 m between rows with plants spaced of 0.30 m. The foundation of fertilization consisted of 200 kg ha-1 formula 05-30-15 + micro-nutrient and coverage on 30 days after sowing, using 30 kg ha-1 of N and 30 kg ha-1 of K2O. In Mata Roma, grain yield in the final test 01 ranged from 1,866 kg ha-1 to 2,567 kg ha-1, obtained at Embrapa 122 and BRS G34 genotypes, respectively, getting the overall average of the test in 2,095 kg ha-1. In the final test 02, the grain yield ranged from 1,705 kg ha-1 to 2,036 kg ha-1 for Helio 250 and MG 360 genotypes, respectively, with overall average of 1,834 kg ha-1. In Magalhães de Almeida the grain yield obtained in the final test consisted of 1,600 kg ha-1 in the genotype Helio 251, 2,110 kg ha-1 in the CF 101 and overall average test of 1,908 kg ha-1. The highest oil content obtained in the three tests were 40.1%, 40.6%, 40.9% and 41.4%, respectively, in the 101 CF genotypes, Heaven 20, BRS G41 and MG 360.

Desempenho morfoagronômico de genótipos de girassol cultivados na Chapada do Araripe, Pernambuco.

RESUMO: Com o objetivo de avaliar o desempenho agronômico de genótipos de girassol nas condições edafoclimáticas do primeiro semestre de 2015 na Chapada do Araripe, instalou-se um experimento na Estação Experimental do Instituto Agronômico de Pernambuco (IPA), no município de Araripina, Estado de Pernambuco. O delineamento foi o de blocos ao acaso, com quatro repetições e 13 tratamentos, correspondendo aos genótipos de girassol: M734, NTC 90, BRS G43, BRS G44, BRS G45, BRS G46, SYN 065, HLA 2013, HLA 2014, HLA 2015, HLA 2016, HLA 2017 e SYN 045. Avaliaram-se as seguintes características: sobrevivência final, floração inicial, maturação fisiológica, altura média do capítulo, peso de 1000 aquênios, diâmetro médio dos capítulos, produção final de aquênios, curvatura do capítulo e plantas acamadas, quebradas e atacadas por pássaros. Os genótipos apresentaram diferenças morfoagronômicas quando cultivados no primeiro semestre em condições edafoclimáticas da região do Araripe, com exceção da variável sobrevivência. O genótipo NTC 90 alcançou o maior peso de aquênios. Todos os genótipos, exceto HLA 2015, apresentaram elevado rendimento de grãos. Os caracteres plantas acamadas, quebradas, atacadas por pássaros ou a curvatura do capítulo não foram relacionadas às diferentes cultivares. ABSTRACT: The study aimed to evaluate the agronomic performance of different sunflower genotypes in edaphoclimatic conditions of Araripe region in the first semester of 2015. The experiment was established at the Experimental Station of Instituto Agronômico de Pernambuco (IPA), Araripina, Pernambuco, Brazil. Experimental design was a randomized blocks with thirteen treatments, corresponding to the sunflower genotypes: M734, NTC 90, BRS G43, BRS G44, BRS G45, BRS G46, SYN 065, HLA 2013, HLA 2014, HLA 2015, HLA 2016, HLA 2017 e SYN 045, with four replicates. The following characteristics were evaluated: final survival, early flowering, physiological maturity, average plant height, weight of 1,000 seeds, average flower diameter, final seed production, flower head curvature, lodged, broken and damaged by birds plants. The genotypes showed morphoagronomic differences when grown in the first semester of 2015 on edaphoclimatic conditions of the Araripe region, except for the variable survival. The NTC 90 genotype achieved the highest weight of head flower. All genotypes, except HLA 2015 showed high grain yield. The characters lodged, broken and damaged plants by birds or curvature of the head flower were not related to the different cultivars.