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971.
硝基双效肥对水稻产量、生产效益及节肥效果的影响   总被引:1,自引:0,他引:1  
通过田间试验,研究了新型硝基双效肥对水稻产量、效益和节肥情况的影响。结果表明,在等养分条件下,硝基双效肥相比常规施肥处理增产0.38%,但与农民习惯施肥处理相比减产2.06%。方差分析结果表明,各处理产量差异均未达到显著水平。施用硝基双效肥处理与农民习惯施肥处理和常规肥料处理效益基本相当,但减肥效果比较明显,小区试验减少率为17.2%,示范对比减少率为24.3%。  相似文献   
972.
2016年采用自然诱发方法测定了金华市10个单季稻主栽品种稻曲病的发病情况,并对其抗性进行了评价。结果表明,深两优5814、甬优17、春优84、中浙优8号、甬优1540、丰两优香1号和Y两优2号对稻曲病的抗性较好,而甬优15、甬优9号、浙优18的抗性较差。  相似文献   
973.
籼粳杂交稻甬优12具有株型优良、穗大粒多、结实率高、高产稳产、优质多抗等特点。2013-2016年在浙江省江山市进行百亩方攻关试验,2016年创造了单产14.56 t/hm~2的浙江省单季稻攻关田历史最高纪录。本文介绍了甬优12的特征特性,并详细阐述了甬优12百亩攻关方单产达13.50 t/hm~2的高产栽培技术。  相似文献   
974.
盆栽试验结果显示,用漯效王1 000、1 200、1 500、2 000倍液浸种甬优12(籼粳杂交稻)和中浙优1号(籼型杂交稻)种子,2个水稻品种的种子发芽率、根长、胚芽长均与清水对照无明显差异。在不施化肥的情况下用漯效王喷施叶面,2个品种的株高、根长、地上部鲜质量、地下部鲜质量、叶绿素相对含量与清水对照也无明显差异。在对处理组施尿素后用漯效王喷施叶面,而对清水、普绿通、可杀得叁仟处理组只施尿素的情况下,漯效王处理的水稻株高、地上部鲜质量、地下部鲜质量、叶绿素相对含量明显优于清水对照、普绿通、可杀得叁仟处理。叶面喷施后14d,漯效王处理组各指标依旧优于对照组。综合试验结果表明,漯效王在与尿素配合施用的情况下能够达到促进肥效、抗虫、促进根部和植株生长、促进分蘖的作用,并且药效持久性好。  相似文献   
975.
2016年我国审定的水稻品种及基本特性分析   总被引:1,自引:0,他引:1  
分析了2016年我国水稻品种的审定情况及通过省级以上审定水稻品种的基本特性.结果表明,2016年我国通过省级以上审定的水稻品种共有492个次(有13个品种通过两个及以上省份审定),其中,籼型常规稻36个、籼型两系杂交稻137个、籼型三系杂交稻166个、粳型常规稻87个、粳型杂交稻25个(其中19个为籼粳杂交稻)、 不育系41个.区试平均产量籼型常规稻为501.36 kg/667 m2,比区试对照增产3.86%;籼型两系杂交稻为592.54 kg/667 m2,比区试对照增产5.46%;籼型三系杂交稻为552.96 kg/667 m2,比区试对照增产5.16%;粳型常规稻为624.94 kg/667 m2,比区试对照增产7.48%;粳型杂交稻为651.96 kg/667 m2,比区试对照增产8.91%.品种品质表现是粳稻好于籼稻,常规稻好于杂交稻,优质达标率粳稻为51.79%、籼稻为43.95%,常规稻为56.91%、杂交水稻为41.77%.并列举了一些对单个病害抗性表现较好的品种.  相似文献   
976.
水稻氮钾吸收的交互作用研究   总被引:2,自引:0,他引:2  
氮和钾都是水稻生长的大量必须营养元素,在水稻的生长发育过程中起着不可替代的作用。水稻对氮、钾的吸收存在着一定的交互作用。本文在综述水稻氮、钾吸收的机理上,探讨了氮素对水稻钾素吸收的影响,以及钾素对水稻氮素吸收的影响。  相似文献   
977.
This study aimed to investigate the possible causes for inconsistent performances of upland New Rice for Africa (NERICA) varieties in uplands and lowlands, while identifying important determinants in grain yield under deficient soil moisture. We compared the growth and yield of NERICA 1 and NERICA 5 to those of Yumenohatamochi, a Japanese upland variety, and Hinohikari, a Japanese lowland variety, subjected to different water management regimes (continually flooded, supplementary irrigation, and non-irrigation). Under conditions of deficient soil moisture, panicle number per square meter, spikelet number per panicle, and 1000-grain weight of NERICAs decreased, whereas the panicle number of the Japanese varieties experienced little change. In contrast, the grain filling ratio was unaffected by water management, irrespective of variety. The primary source of yield reduction under low soil water conditions was a decrease in spikelet number per panicle, and water stress intensity was the primary factor for the degree of this reduction. Variation in the abortion of secondary rachis-branches caused differences between NERICAs in their spikelet number response to soil moisture deficiency. The inconsistency in NERICA performance across uplands vs. lowlands can be partially attributed to variation in yield response to low soil water conditions. Moreover, water stress intensity and the presence of a water gradient along the vertical soil profile may combine to affect the fluctuation in NERICA performance under upland conditions.  相似文献   
978.
Seed coating with molybdenum compounds improves seedling establishment for rice, wheat, barley, and soybean when such seeds were sown under flooded conditions. Tungsten belongs to the same chemical group as molybdenum in the periodic table, and similar to molybdenum, inhibits the generation of sulfide ions. Here, the effects of tungsten and molybdenum containing seed coatings on seedling establishment under flooded conditions were compared using rice, wheat, barley, and soybean. In rice, the effects of tungsten compounds on seedling establishment varied. Tungsten trioxide had little effect but tungstic acid and ammonium phosphotungstate significantly improved seedling establishment when the amounts were at least .1–.2 mol W kg?1. Although the effect of tungsten coating varied depending on the compound used, ammonium phosphotungstate, along with other tungsten compounds, improved seedling establishment in a manner comparable with that of molybdenum compounds. For wheat and barley, ammonium phosphotungstate treatment resulted in a significant increase in establishment that was only slightly less than the results observed using molybdenum compounds. Tungstic acid and ammonium phosphotungstate treatments improved soybean establishment in a significant manner that was comparable with those of molybdenum compounds. Collectively, these results suggest that tungsten compounds, as well as molybdenum compounds, improve seedling establishment under flooded conditions.  相似文献   
979.
The genes TAWAWA1 (TAW1) and ABERRANT PANICLE ORGANIZATION1 (APO1) increase the number of spikelets per panicle (SN). In the present study, we examined the effects of these genes on morphological traits, yield, and yield-related traits including yield components using the near-isogenic lines (NILs) in the genetic background of a japonica rice variety, Koshihikari – NIL-taw1, NIL-apo1-D3, and NIL-apo1-D4 – in a field experiment. The SN and total number of spikelets per area of the three NILs were larger than those of Koshihikari. However, the yield of the three NILs did not exceed that of Koshihikari due to their low filling ability. Interestingly, our field experiments indicated that TAW1 did not affect the diameter of internodes and the PN, whereas APO1 decreased the PN and increased the diameter of internodes. These results suggest that TAW1 and APO1 differently affect yield-related traits.  相似文献   
980.
γ-Oryzanol is a main oleophilic component in rice bran oil and has been well recognized as a good dietary supplement for human health, as well as having uses in industrial materials. japonica-type rice cultivars generally showed significantly higher contents of total γ-oryzanol in brown rice compared with indica-type cultivars, although within-group variation was significant. The objective of this study was to explore quantitative trait loci (QTLs) responsible for the difference in the γ-oryzanol content between japonica-type and indica-type rice cultivars, using recombinant inbred lines (RILs), backcross inbred lines (BILs), and corresponding chromosome segment substitution lines (CSSLs) derived from crosses between japonica-type and indica-type. Results from RILs and BILs showed that eight QTLs were detected with R2 from .09 to .16. Nine candidate regions for QTL were also suggested from corresponding CSSLs. These QTLs from RILs and BILs and the candidate regions from CSSLs were not overlapped, although one QTLs was mapped near the boundaries of the respective candidate region. At four QTLs and three candidate regions, alleles or segments from japonica-type caused higher contents than those from indica-type. On the other hand, at the other four QTLs and six candidate regions, alleles or segments from indica-type caused higher contents than those from japonica-type, which is a reverse result to the parental differences. This result strongly suggested that alleles with increasing effects on γ-oryzanol content could be accumulated not only from japonica-type but also from indica-type, leading to a potential for increase in γ-oryzanol content in future breeding programs.  相似文献   
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