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为探索独山县直播稻适宜的播期,开展了4个不同播期的比较试验。结果表明：播种期在4月5日、4月15日,水稻穗实粒数、结实率高于在4月25日、5月5日播种,其单产较高,分别为773．8kg／667m2、760．1kg／667m2,并显著高于在4月25日、5月5日播种。在大田生产中,独山县最佳播种期为4月上旬末至4月中旬。 相似文献
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淮北地区水稻不同栽培方式的比较研究 总被引：7，自引：1，他引：6
试验研究了不同栽培方式对淮北水稻产量的影响。结果表明:产量水平手插秧机插秧直播稻。在手插条件下适宜淮北稻区中熟中粳品种全生育期积温不应小于3450℃光照时数小于780h,机插秧不应小于3100℃光照时数小于660h,安全生育期直播稻为不应小于2600℃光照时数小于550h。全生育期积温均表现出手栽稻机插稻直播稻,手栽稻高出直播稻18.1%;日照时数也均是手栽稻机插稻直播稻,手栽稻较直播稻高出20%。直播稻产量均低于手栽稻20%以上,机插稻的产量均低于手栽稻6%以上,手栽稻产量最高,其次是机插稻,直播稻最低。在产量构成因素上,直播稻穗数大于机插稻的穗数大于手栽稻,而直播稻机插稻穗粒数显著低于手栽稻,结实率和千粒重差异不大,由于直播稻、机插稻总颖花量少,产量均不及手栽稻。 相似文献
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为探索适宜独山县大面积推广应用的直播稻播种密度,在相同株距和播种量条件下,开展了1.11万穴/667m2、1.19万穴/667m2、1.28万穴/667m2、1.37万穴/667m2、1.49万穴/667m2、1.62万穴/667m2等6个不同密度的试验研究。结果表明:直播稻在不同密度下对水稻生育期没有影响。从农艺性状来看,随密度的增加,株高有增高的趋势,穗长有缩短的趋势,有效穗有增加的趋势,但穗粒数、结实率则逐渐有减少和降低的趋势,各处理间千粒重无明显差异。从产量上看,从1.11万穴/667m2增加到1.37万穴/667m2时,产量呈递增趋势,密度从1.37万穴/667m2增加到1.62万穴/667m2时,产量呈递减趋势。密度在1.37万穴/667m2与1.49万穴/667m2时,其产量无显著差异。说明在独山县或者相似生态条件地区,以C两优华占为应用品种的前提下,直播密度在1.37万～1.49万穴/667m2时可获得较高产量,可在大面积生产上应用。 相似文献
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直播稻田杂草发生与防除研究进展 总被引：4，自引：0，他引：4
随着水稻直播技术的推广,稻田出现杂草发生严重、除草剂用量加大等问题,而杂草发生种类、优势种群出现多样化,增加了杂草对除草剂的抗性,导致杂草防除困难,影响了直播稻的丰产与稳产;同时直播稻田除草剂的过量使用带来的生产安全性问题值得关注。本文从杂草发生种类、数量及成灾时期、发生差异性（稻作区域、种植方式、直播方式与播种期）、生态学效应及对直播稻生长发育影响等方面综述了直播稻田杂草的发生特性,分析了不同种类杂草的防除途径（化学除草、耕种制度与栽培措施）,提出我国目前在直播稻田杂草发生与防除方面研究存在的问题,并对未来直播稻田杂草防治的发展方向进行探讨与展望,旨在提高我国直播稻田杂草的防除效果,促进直播稻生产的轻简高效发展。 相似文献
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<正>随着直播稻面积扩大,种植年限延长,杂草稻和假稻这"两稻"在江苏省南北各地直播稻田严重发生和危害,成为困扰直播稻生产的两大难题。在"两稻"发生和危害较重的田块,将直播种稻改成栽插种稻,包括手栽 相似文献
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沿海地区直播稻种植后效应及其思考 总被引：1，自引：0，他引：1
江苏沿海地区直播稻连茬种植后优劣效应共显,直播稻可以直接节省种植用工,改变水稻病虫发生危害特点,调整了稻田土壤理化性质,使得养分等有利生长因素在土壤表层富集,种植收益相对稳定,但杂草（稻）危害逐年加重,水稻安全生产的风险增加。因此,应客观认识直播稻栽培后效应,加大宣传与指导力度,普及直播稻栽培技术及生产风险,树立粮食安全生产的全局观念,科学规划种植布局,从整个农业生态系可持续发展的观点来指导直播稻生产。 相似文献
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麦茬旱种水稻苗期施氮效应的研究 总被引：7，自引：0，他引：7
1985～1986年,在田间和盆栽试验条件下,采用~(15)N示踪技术,对麦茬旱种水稻苗期施氮(三叶一心期前)与产量形成的关系及苗期需氮规律进行了探索.结果表明,苗期植株氮主要来源于土壤,追肥氮所占比重只有1/4～1/5.研究还表明,麦茬旱种水稻苗期对氮肥的利用率较低,认为培肥土壤对麦茬旱种水稻幼苗生长很重要.因而,从经济观点分析,在土壤肥力较高的条件下,苗期不宜施氮. 相似文献
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K. Ramesh B. Chandrasekaran T. N. Balasubramanian U. Bangarusamy R. Sivasamy & N. Sankaran 《Journal of Agronomy and Crop Science》2002,188(2):102-105
The rice plant at any point in time is composed of leaves of physiologically different ages, so it follows that the leaves differ in their contributions to the growth of the whole plant and its grain yield. As the leaf chlorophyll content (Soil Plant Analytical Division value) is the best indicator of photosynthetic activity in rice, the chlorophyll content of rice before and after flowering was determined in a weed management field experiment on direct wet seeded rice. The results indicated that the leaf chlorophyll content at 79 days after sowing correlated well with the grain yield of rice. Multiple regression models also indicated the dependence of rice yield on leaf chlorophyll content before and after flowering. 相似文献
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The rice (Oryza sativa L.) crop in Arkansas is seeded from late March through early June each year. Farmers need new rice
cultivars that not only produce both high rough rice yields and high head rice across this range of seeding dates but do so
consistently. Thus, a seeding date study was conducted during 1994 and 1995 at Stuttgart, Arkansas, to study seeding date
effects on rough rice yield and head rice and selection for stability. Fourteen rice cultivars were seeded at five dates ranging
from late March through mid-June. Kang's yield-stability statistic was used to select cultivars for both high rough rice yields
and high head rice as well as stability for both traits. Plant stands from March seedings of each year were significantly
lower than for the later seeding dates. Maturity (days to 50 percent heading) was extended at the early seeding dates. Some
rice cultivars, such as ‘LaGrue’, had lower and more variable head rice when seeded early. In the June seeding dates each
year, ‘Kaybonnet’ produced rough rice yields that were more consistent with yields when planted at the earlier planting dates.
‘Bengal’, ‘Cypress’, ‘Kaybonnet’, and ‘Newbonnet’ were cultivars selected by Kang's stability statistic, which was targeted
to select cultivars with stable, high rough rice yields and stable, high head rice. The validity of using Kang's yield-stability
statistic for cultivar selection is also evident empirically by the adaptation and wide use of these four cultivars by southern
U.S. rice producers. These results indicate that seeding date studies and stability analyses would be useful tools for rice
breeders to identify cultivars that will be readily adapted and grown by rice producers.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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麦茬水稻旱种田间杂草综合防除研究初报 总被引：6，自引：0，他引：6
在田间条件下,研究了杂草的发生危害规律及防除关键技术等.初步认为:1.杂草对旱种水稻生长的影响主要表现在降低产量,减少成穗数、结实率、千粒重和穗长;2.杂草累计收获总干重或禾本科杂草干重可作为杂草危害程度的指标;3.禾本科杂草危害较严重,是旱种水稻田的优势草类;4.旱种水稻除草临界期为播种后第25～40天.此外,对杂草发生潜力、除草时期等也进行了讨论. 相似文献
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河南沿黄稻区是我国优质粳米生产基地,随着水稻简化耕作栽培方式的发展,直播稻因其简单易行的优点而具有广阔的推广前景。[目的]为研究沿黄稻区直播稻稻米品质与常规插秧稻米品质的差异,[方法]本研究选取6个直播水稻品种和8个插秧水稻品种以及7种优质商品稻米,对其加工品质、外观品质、食味品质以及营养品质性状进行系统比较。[结果]结果表明：整体上,直播稻的精米率高于插秧稻,垩白粒率和垩白度、直链淀粉含量、以及食味值低于插秧稻,高于商品稻米;蛋白质含量高于插秧稻,低于商品稻米;除此之外,相对于插秧稻和商品稻米,直播稻品种的崩解值最大,消减值最小;缬氨酸和胱氨酸含量最高,蛋氨酸含量最低,其余氨基酸含量均低于插秧稻品质,高于商品稻米。[结论]综合所有品质性状指标发现,在选取的6个直播稻品种中,新稻568、郑稻201和新稻567在河南沿黄地区直播条件下的稻米加工品质、外观品质、食味品质以及营养品质都与常规栽培的优质稻米相当,因此可以通过品种选择在保障产量与品质的前提下通过直播简化水稻栽培过程。 相似文献
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不同播期对直播早稻干物质积累的影响 总被引：1，自引：0，他引：1
为明确播期对直播早稻个体和群体干物质积累的影响。以常规籼稻中早35和中早39为材料,利用大田分期播种试验,分析不同播期直播早稻干物质积累及转运的差异。结果表明,随播期推迟,全生育期积温逐渐减少,抽穗后积温逐渐增加。成苗率随分蘖前日平均温度升高而增加,成苗率与单株干物质积累量呈系数为0.83以上的极显著负相关关系,与单位面积干物质积累量呈系数为0.72以上的显著正相关关系。随播期推迟,茎叶干物质向子粒输出转化逐渐减少,单株和单位面积茎叶干物质输出转化与抽穗后积温呈负相关关系,单株抽穗后光合产物积累量随积温增加而减少,单位面积抽穗后光合产物积累量随积温增加而增加。在水稻直播生产过程中,提前播种,保证一定基本苗,协调好个体和群体干物质积累和转化,能获得较高产量。 相似文献
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No tillage (NT) in wheat (Triticum aestivum L.) offers a pragmatic option for resolving the time and edaphic conflicts in rice (Oryza sativa L.)–wheat cropping system (RWS). However, poor stand establishment is an issue in NT wheat, which adversely affects crop growth, grain yield, and profitability. Therefore, a 2-year field study was conducted to assess the potential role of seed priming in improving the stand establishment, grain yield, water productivity and profitability of NT and plough till (PT) wheat grown after direct seeded aerobic (conservation) and puddled transplanted flooded (conventional) rice-based systems. For seed priming, wheat seeds were soaked in aerated water (hydropriming) or solution of CaCl2 (ψs −1.25 MPa; osmopriming) for 12 h, and non-primed seeds were used as control. After harvest of rice, grown as direct seeded aerobic and puddled transplanted flooded crop, primed and non-primed wheat seeds were sown following NT and PT. In both years, stand establishment of NT wheat after direct seeded aerobic and puddled transplanted flooded rice was impeded. Nonetheless, seed priming improved the stand establishment which was visible through earliness and better uniformity of seedling emergence. Overall, primed seeds completed 50% emergence in 6.4 days, against 7.8 days taken by non-primed seeds in NT wheat. The highest emergence index (41.7) was recorded in primed seeds versus 32.0 for non-primed seeds. Improved stand establishment enhanced growth, grain yield, water productivity and profitability in NT wheat. In this regard, osmopriming was the most effective, and produced grain yield of 4.5 Mg ha−1 against 3.8 Mg ha−1 for non-primed seeds in NT wheat. Water productivity of the NT wheat grown from osmoprimed seeds was 8.72 kg ha−1 mm−1 while that from non-primed seeds was 7.21 kg ha−1 mm−1. Among the RWSs, the maximum wheat biomass was produced with PT after direct seeded aerobic rice. However, grain yield, water productivity, and profitability were the highest in NT wheat following direct seeded aerobic rice. Wheat yields grown after direct seeded aerobic rice and transplanted flooded rice were 4.4 and 4.2 Mg ha−1 respectively. Planting NT wheat after direct seeded aerobic rice provided the highest system productivity (1.80) than other RWSs. Thus, seed priming is a viable option to improve the stand establishment, grain yield, water productivity and profitability of NT wheat in the RWS. Nonetheless, osmopriming was a better option than hydropriming in this regard. 相似文献