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杂草稻与栽培稻叶片生长的竞争性研究 总被引:1,自引:1,他引:0
杂草稻造成栽培稻产量的损失主要表现为叶片间的相互竞争。争夺空间、争夺光照矛盾突出。杂草稻主茎叶片多于栽培稻,最大叶片长于栽培稻,最大叶片宽于栽培稻,叶片披散,形似杂交稻叶。如果在667 m2旱直播稻田接种2.5 kg粳性杂草稻籽,栽培稻上部全被杂草稻稻叶覆盖,栽培稻植株瘦黄、弱小,茎、蘖逐步退化消亡,造成基本绝产。 相似文献
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噁草酮防除直播稻田杂草稻的施用技术 总被引:4,自引:0,他引:4
为确立噁草酮防除直播稻田杂草稻的施用技术,通过温室盆栽试验比较了噁草酮在不同土壤水分环境下对栽培稻的安全性及对杂草稻的防效,并在大田中比较了不同直播方式下其对杂草稻的防效及栽培稻产量的影响。结果表明,透气条件下,噁草酮对栽培稻的药害最低,但对杂草稻的防效也较差;饱和水分条件下对杂草稻防效较好,150 g(a.i.)/hm~2时其出苗率和鲜重的抑制率达89.61%和61.87%,超过450 g(a.i.)/hm~2时完全抑制出苗;但药后播种对栽培稻安全性较高,600 g(a.i.)/hm~2下对其出苗率和鲜重的抑制率仅分别为38.06%和39.96%,播后施药的药害较重,最低剂量150 g(a.i.)/hm~2时抑制率已分别达88.77%和45.52%;淹水条件下,虽对杂草稻有100%的防效,但也完全抑制栽培稻出苗。大田施用噁草酮300、450、600 g(a.i.)/hm~2,旱直播和水直播方式下杂草稻株防效分别为26.88%、43.54%、44.45%和84.88%、85.74%、90.92%;鲜重防效分别为11.58%、20.16%、27.33%和30.86%、53.68%、80.15%。旱直播和水直播方式下施用量分别超过450、300 g/hm~2时栽培稻产量显著增加。综合分析,推荐水直播整地后泥水状态施用300 g(a.i.)/hm~2噁草酮,水层落干后播种,保持土壤湿润且土表不出现水渍,栽培稻顺利出苗后及时上水且不淹没苗心为宜。 相似文献
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杂草稻对水稻生长及产量的影响 总被引:6,自引:0,他引:6
通过室内试验和田间试验明确了杂草稻对水稻生长、产量构成因子和产量的影响。水稻营养生长期,不同杂草稻密度对水稻基本苗、株高、单株鲜重、分蘖、倒二叶长与宽均没有影响。而水稻株高、有效穗数、穗长、一次枝梗数、穗粒数、千粒重、结实率、实际产量等均随杂草稻密度的增加而呈现下降趋势。杂草稻密度为1株/m2可导致水稻产量损失9.15%,当杂草稻密度达7株/m2时可导致水稻产量损失50%以上,杂草稻密度达到12株/m2时水稻产量损失可高达72.29%。 相似文献
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近年来杂草稻在江苏省大面积水稻田发生,尤其是苏中地区发生较严重,在少数田块已成为比稗草和千金子危害更重的杂草。杂草稻植株生长繁茂,在稻田与栽培稻争夺阳光、养分和水分,并且自身早熟,落粒性强,严重影响水稻产量。另外,部分未落粒的杂草稻与栽培稻一起收获,因粒型小,果皮有色素沉淀,也会影响稻米加工及外观品质。 相似文献
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丙草胺防治直播稻田杂草稻的技术研究 总被引:2,自引:0,他引:2
为了探寻对栽培稻安全的杂草稻防除技术,采用整株测定法研究了丙草胺对杂草稻的毒力及解草啶减轻丙草胺对栽培稻药害的应用技术,并通过田间试验检验了这一技术的安全性。结果表明:丙草胺在450g/hm2时,可显著抑制杂草稻和栽培稻的生长;采用30mg/L解草啶浸种48h,可显著减轻丙草胺对栽培稻的药害,随着丙草胺施药量的增加,解草啶的保护作用逐渐减弱。田间试验结果说明:用30mg/L解草啶浸种栽培稻48h,丙草胺的施药剂量在450~675g/hm2时对栽培稻安全;当丙草胺剂量为900g/hm2时,栽培稻产量显著下降。 相似文献
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通过田间试验初步研究采自上海市青浦区、浦东新区、嘉定区等地的籼型和偏籼型杂草稻以及采自崇明区的粳型杂草稻对水稻生长、产量构成因子和产量的影响。结果表明,在水稻营养生长期,不同籼型、偏籼型杂草稻密度对水稻基本苗、株高、单株鲜质量、分蘖数、倒二叶长、倒二叶宽均未有明显影响;而籼型和偏籼型杂草稻密度对产量构成因子有效穗数、穗长、一次枝梗数、穗粒数、千粒质量、结实率等均能产生一定影响,而粳型杂草稻只对水稻有效穗数、结实率、千粒质量等产生一定影响,实际产量等均随杂草稻密度的增加呈下降趋势。青浦区、浦东新区、嘉定区等地的籼型、偏籼型杂草稻和崇明区粳型杂草稻导致水稻产量损失50%时的密度分别为8.19、12.82、15.45、19.82株/m~2。 相似文献
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自2007年开始,对杂草稻发生情况进行了逐年调查。在调查的基础上,分析了影响杂草稻发生的主要因素,开展了田间危害试验。结果表明,杂草稻已成为江苏省海安县稻田的重要杂草,水稻大田的田块查见率已达70%以上,水稻育秧田的田户查见率近40%。单位面积杂草稻的发生密度表现为直播>抛栽>机插>手栽稻田,非统一供种田>统一供种田,杂草稻的生长势以及对邻近栽培稻株生长的影响表现为混生苗>次生苗。 相似文献
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Impact of weedy rice populations on the growth and yield of direct-seeded and transplanted rice 总被引:1,自引:0,他引:1
QIAN JIN CAO BO LI ZHI PING SONG XING XING CAI BAO-RONG LU 《Weed Biology and Management》2007,7(2):97-104
To examine the impact of weedy rice ( Oryza sativa L. f. spontanea ) populations on the growth and yield of direct-seeded and transplanted rice ( Oryza sativa ), a field experiment with a random two-factor design that included cultivation methods (direct-seeding and transplanting) and the density of weedy rice (0, 5, 25, and 125 plants per m2 ) was conducted. The data from the experiment showed that weedy rice had a significantly poorer performance in the direct-seeded fields than in the transplanted fields in terms of its vegetative (plant height) and reproductive traits (panicle and seed production). In contrast, with the interference of weedy rice, cultivated rice showed an improved performance in the direct-seeded fields than in the transplanted fields, with a significantly higher tiller production and grain yield. The results suggest that cultivated rice can tolerate more successfully the infestation of weedy rice in direct-seeded fields because of its enhanced competitive ability compared to that in transplanted fields. 相似文献
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Toshiyuki Imaizumi 《Weed Biology and Management》2018,18(2):99-102
Weedy rice is a conspecific weed of cultivated rice (Oryza sativa L.) and is a primary weed of direct‐seeded rice production systems worldwide. The shift in the method of establishing rice, that is, from transplanting to direct seeding, is considered the main reason for the emergence of weedy rice in Asia and, more recently, Japan. Japan has increasingly adopted directly seeded rice, even though this practice remains limited. In this study, I confirmed the relationship between weedy red rice emergence and the adoption of direct‐seeded rice in Japan. Twenty‐seven areas from eight prefectures infested with weedy rice were selected to confirm the relationship between the rice planting method and the emergence of weedy rice. Fields that were severely infested with weedy rice were selected as survey fields for this study. I found no relationship between the method of planting rice and weedy rice emergence. Changes to herbicide application, duration of rice production and hand weeding also contribute to the emergence of weedy rice in transplanted rice fields in Japan. The results of this study indicate that weedy rice could become a serious problem in Japan, even in transplanted rice fields. 相似文献
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杂草稻研究现状及利用展望 总被引:1,自引:0,他引:1
杂草稻作为一种稻田伴生杂草,严重影响了水稻的产量和稻米品质。尤其是近年来随着直播稻的推广和机械化程度的提高,杂草稻的危害有加重的趋势。同时,杂草稻的抗逆性非常强,与水稻的亲缘关系也非常近,是一个极有利用价值的天然基因库,是水稻育种的宝贵资源。本文就杂草稻的生物学特性、分布、起源、分类、防除等方面的研究做了概述,并对其利用前景进行展望,提出了有待进一步深入研究的问题。 相似文献