Seed Yield and Quality of Winter Oilseed Rape as Affected by Nitrogen Rates,Sowing Time,and Fungicide Application

Abstract

This work reports the results of studies on the impact of sowing times (three dates), application of fungicides (protected and unprotected plots), and nitrogen rates (five treatments) on the seed yield, contents of crude protein (CP), glucosinolates (GSL), and crude fat (CF) in seed and on major unsaturated acids (oleic C18:1, linoleic C18:2, and linolenic C18:3) in oil of winter rape (Brassica napus L.) cv. Kasimir. A split–split plot design was used in the field trial conducted on Endocalcari–Epihypogleyic Cambisol during 1998–2002. Seed samples were analyzed by near infrared spectroscopy. ANOVA analysis was used to assess the significance of each factor for the yield and quality of seed of the tested cultivar. The seed yield significantly depended on harvest year, N rates annually, sowing time in three experimental years, and fungicide application in two years. CF and CP concentrations were significantly affected by sowing time and N rates each year of the experiment. A significant effect of fungicides was identified only in one harvest year. GSL concentration was significantly affected by sowing time in three years, by fungicides in two years, and by nitrogen rate annually. The effect of the studied factors on the composition of major unsaturated acids was inconsistent. Sowing time significantly affected the content of all three unsaturated acids in two years and fungicides only in one of the four harvest years.     

分期播种对耐高温东北粳稻农艺性状的影响及耐热性评价

用5份耐高温东北粳稻(“东稻2号”、“东农03-33”、“东农415-1”、“合江195”和“吉粳3”)为材料在中国科学院亚热带农业生态研究所长沙水稻试验站进行分期播种试验(播种日期分别为2011年3月20日、3月30日、4月9日、4月19日、4月29日、5月9日、5月19日和5月29日),研究了分期播种对供试材料株高、主穗穗长、结实率、千粒重、单株穗数、每穗总粒数、单株产量等农艺性状的影响,并分析了自然温度与结实率的关系,评价了供试材料在抽穗扬花期的耐热性.研究结果表明,随着播种期推迟各品种播始历期逐渐变短,不同播种期间的单株穗数、每穗总粒数、单株产量变异幅度较大,而株高、主穗穗长、结实率、千粒重在不同播种期间的变异幅度较小.结实率与日最高温度和日平均温度均呈负相关,“合江195”结实率受温度影响最小,“东稻2号”、“东农03-33”、“东农415-1”的结实率与温度显著相关(P＜0.05),“吉粳3”为极显著相关(P＜0.01).回归分析发现,在一定温度范围内,结实率与温度呈二次曲线关系,且日最高温度和日平均温度对结实率的影响具有一致性.抽穗扬花期遇到高温的各播种期处理材料,除“东农03-33”5月29日播种结实率为58.7％、“吉粳3”5月19日播种结实率为52.5％外,其他材料结实率均在64.9％～75.1％之间,表现出较强的耐热性.综合分期播种的田间农艺性状表现和各材料结实率与自然温度之间的关系,认为“东稻2号”和“合江195”适合作为早稻在湖南种植.     

闽西山区再生稻品种筛选试验及高产栽培技术

针对福建省武平县部分稻田光温资源种植水稻一季有余、两季不足的问题,在进行品种对比试验的基础上,筛选出了适宜武平作再生稻栽培的天优3301等高产品种,并对这些品种作再生稻进行高产栽培示范和最佳播种期比较试验,总结了"早播中稻-再生稻"高产栽培技术。     

不同播种期对杂交晚稻天优8019产量及农艺性状的影响

不同播期试验结果表明,天优8019属感温性品种,但其秧龄弹性较大。在衢州作连作晚稻种植,表现为株型紧凑,耐肥抗倒,成穗率高,穗大粒多,产量潜力较大,但必须掌握适期播种才能实现高产稳产。在本试验条件下,以6月20-25日播种,秧龄控制在30~35 d,叶龄8.9~9.4叶时移栽,保证本田有3.08~3.27叶的营养生长叶龄,较有利于实现其高产高效的目标。     

春播与复播油葵产量形成及群体生理参数比较研究

在新疆石河子地区,在滴灌、种植密度和田间配置方式相同的条件下,比较了春播与复播油葵品种新葵20号产量形成及群体生理参数。结果表明,春播条件下,生育期、生物产量、籽实产量、收获指数分别为97d、9271.9 kg/hm2、4349.0 kg/hm2、0.47,复播条件下则分别为 94d、14413.5 kg/hm2、4106.4 kg/hm2、0.35。春播和复播的最大叶面积指数（LAImax）分别为4.54和5.52。每公顷春播的光合势(LAD)为93.25m2?d,开花后占77.6%;复播则为94.12m2?d,开花后占82.9%。春、复播全生育期平均净同化率（NAR）分别为3.67、5.26g/(m2?d)。采用更早熟的品种,提早播种,使灌浆提前,加之使用植物生长调节剂以增强光合产物向籽实转移,有望进一步提高复播油葵产量。      

耕层优化双行匀播对小麦产量及叶片光合特性的影响

为揭示小麦耕层优化双行匀播栽培技术的增产机理,通过田间试验,以鲁原502为材料,对旋耕、深耕和耕层优化双行匀播3种耕作技术下冬小麦群体动态、叶面积指数、顶部展开叶光合特性、水分利用效率、生物产量、籽粒产量及其结构进行比较分析。结果表明,耕层优化双行匀播技术能提高小麦群体分蘖能力及分蘖成穗率,在生育中后期可有效延缓旗叶叶绿素降解,延长光合时间,提高光合强度,维持较高的叶面积指数,促进干物质积累和转化。与深耕、旋耕相比,耕层优化双行匀播技术使小麦灌浆中后期旗叶水分利用效率分别提高了14.12%和19.21%,旗叶光合速率增加了13.33%和25.08%,增产8.11%和13.29%。     

Agronomic factors affecting the yield and quality of forage maize in Ireland: effect of plastic film system and seeding rate

The objectives were to compare the effects of two plastic film systems [perforated (PP) and complete‐cover (CC) systems] on the yield and quality of forage maize, and to study the effects of seeding rate on maize grown with, and without, plastic film. Between 1995 and 1998 (Experiments 1 and 2), comparisons were made of maize without plastic film systems (NP), sown through clear plastic film (PP) and covered with clear plastic film (CC). In the CC system, the plastic was removed manually from the crop. Two dates of removal (CC1 and CC2) were compared in 1995, while four removal dates (CC1, CC2, CC3 and CC4) were examined in 1996–98. In 1996–98, three sowing dates (early, mid‐April; mid, early‐May; late, mid‐May) were also examined. Four seeding rates (78 200, 93 900, 107 000 and 126 000 seeds ha^?1) were examined in two experiments (Experiment 3 in 1996 and Experiment 4 in 1996–98). No plastic was used in Experiment 3, while three plastic treatments (NP, PP and CC) were examined in Experiment 4. In the CC treatment, the plastic film was removed at the six‐ to eight‐leaf stage. In Experiment 1, the PP treatment gave lower DM yields than the NP treatment due to frost damage which killed 0·30 of the plants in the PP treatment. Plants were undamaged by frost in both CC treatments, and the CC2 treatment (plastic removal at the six‐leaf stage) gave significant increases in DM and grain yields. In Experiment 2, averaged over years and sowing dates, DM yields were significantly increased by all plastic film treatments except CC4. All plastic film treatments gave significantly earlier tassel emergence than the NP treatment, and significantly increased grain yields and contents of DM and grain. The highest yields of DM and grain were obtained from the PP system. Within the CC treatments, leaving the plastic film intact until the ten‐leaf stage (CC4) gave lower yields of DM and grain than removing the plastic film at an earlier stage. Averaged over years, the largest DM yields were obtained from the CC system with early‐sown material, while the yield differences between treatments with late‐sown crops under this system were not significant. Highest DM and grain yields were obtained with early sowing, while late sowing gave lower contents of DM and grain, and later tassel emergence. In Experiments 3 and 4, DM and grain yields increased as seeding rate increased up to 126 000 seeds ha^?1 with NP and CC plastic treatments. With the PP treatment, DM yield reached a plateau at 107 000 seeds ha^?1. Seeding rate did not significantly affect DM content in either experiments but grain content declined in both experiments as seeding rate increased.     

混播草皮缓冲带对农田径流氮磷去除效果研究

草皮缓冲带作为防治农业面源污染的一种有效技术得到越来越广泛的应用。以去除氮磷效果最佳为目标,提出了将草皮混播技术运用到缓冲带的构建中,并筛选出了合理的草种混播比例。根据豆科牧草和禾本科牧草的相容性,选择扬州本地具有推广价值的草坪草本植物白花三叶草(Trifolium repens)与高羊茅(Festuca arundinacea)作为供试植被,研究不同草种混播比例下草皮缓冲带对农田径流污染物的去除效果。结果表明,在总氮、总磷进水浓度分别为7.78~27.22mg/L和0.47~1.61 mg/L的试验条件下,混播草皮的存在明显提高缓冲带对污染物的去除效果,且对渗流水污染物的去除效果明显高于径流,当白花三叶草与高羊茅混播比例为1∶3时,缓冲带对径流水和渗流水中总氮、总磷的去除效果较好,且植物生长状况良好,具有较好的环境适应性。     

种子贮藏和播种方式对红椆发芽及苗木生长的影响

以红椆种子为试验材料,进行贮藏和播种方式对红椆种子发芽和苗木生长的影响试验。结果表明:不同贮藏方式对红椆种子发芽率有极显著影响;不同播种方式对红椆种子发芽率和苗木地径生长无显著影响,但对苗木成活率和苗木高生长影响极显著。