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扁杆藨草持续危害对棉花农艺和经济性状的影响 总被引:1,自引:0,他引:1
【目的】研究扁杆藨草持续危害对棉花的影响,为棉田该杂草科学防治提供依据。【方法】扁杆藨草种群密度设为60 株/m2 ,测定其持续危害0、10、20、30、40、50 、60 d和全生育期棉花株高、茎粗、主茎节数、结铃数、单铃重、产量和纤维品质指标。【结果】棉花株高和茎粗随扁杆藨草危害持续期延长而减小。扁杆藨草持续危害期小于30 d,对棉花主茎节数和果枝数影响不显著,大于30 d则显著减少。扁杆藨草持续危害期对棉花中部和下部果枝结铃数影响不显著,显著引起上部果枝结铃数、单铃重减少。扁杆藨草持续危害期大于10 d,可使棉花产量显著减少,导致棉纤维品质指标下降。【结论】依据棉花产量指标,扁杆藨草防除应不晚于棉花打顶前30 d。 相似文献
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松嫩平原扁秆藨草种群生殖株构件表型可塑性及生长分析 总被引:1,自引:1,他引:0
采用大样本取样野外实地测定方法,对松嫩平原扁秆藨草(Scirpus planiculmis)种群生殖株的数量性状和生殖分配规律进行了分析。结果表明,在籽实成熟期,扁秆藨草种群生殖株各数量性状具有较大的表型可塑性。变异系数以种子生物量最大,为81.63%;其次为种子生殖分配73.14%;株高最小,为13.11%。扁秆藨草种群生殖株表型可塑性遵循着规律性,即随着株高和株生物量的增加,茎叶生物量呈幂函数增加,花序生物量呈直线增加;生殖分配随着株高和株生物量的增加呈幂函数或指数减少。 相似文献
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2甲4氯钠防除稻田扁杆镳草药效试验 总被引:1,自引:0,他引:1
采用不同剂量对比试验,研究了2甲4氯钠粉剂对稻田扁杆镳草的防除效果。结果表明:在水稻分蘖盛期,用2甲4氯钠粉剂2.25kg/hm^2进行茎叶喷雾,可有效防除杂草,且对水稻生长无不良影响。 相似文献
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为明确扁秆荆三棱不同种群密度对棉花形态指标?产量和品质的影响?本试验将扁秆荆三棱种群密度设为0?20?40?60?80?100株/m 26个梯度, 在棉花整个生长期每10 d测一次株高?茎粗和主茎节数, 采收期测棉花单株结铃数?单铃重?产量和纤维品质?扁秆荆三棱对棉花株高?茎粗和主茎节数影响随扁秆荆三棱种群密度的增大而增加?扁秆荆三棱种群密度为80株/m 2时对棉花第6节果枝以上结铃数和单铃重影响最大, 结铃数和单铃重相对于对照分别减少了2.86个和1.82 g?棉花的产量随扁秆荆三棱种群密度的增加而降低, 其中扁秆荆三棱种群密度为20株/m 2时影响不大?对棉花纤维品质的影响主要表现在对棉纤维马克隆值的影响和成熟度的影响?扁秆荆三棱种群密度能显著影响棉花株高?茎粗和主茎节数, 进而对棉花产量产生极大影响?扁秆荆三棱种群密度为20株/m 2时对棉花产量和品质影响不大, 因此应将扁秆荆三棱种群密度控制在20株/m 2以下? 相似文献
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Alain Audebert Jean Claude Mouret Sandrine Roques Alain Carrara Roy Hammond Azaad Gaungoo Suchada Sanusan Pascal Marnotte 《Weed Biology and Management》2013,13(2):70-78
Bolboschoenus maritimus is one of the major weed constraints for irrigated rice‐cropping systems in the Camargue, France. This perennial plant propagates mainly through the production of numerous tubers. Observations in both controlled conditions and on‐field studies were used to enhance the level of knowledge of the biology, functioning and infestation dynamics of B. maritimus, with a view to rationalize weed control practices. It was found that B. maritimus displayed a great potential to produce a large number of shoots, rhizomes and tubers. Its propagation in the field plots depended on the initial weed density and its spatial colonization did not show any preferred direction (isotropic). Further observations that were made in the paddy fields showed an interaction between the different cultural practices that were tested and the infestation dynamics of B. maritimus. Efficient control of B. maritimus infestation in the field should make use of the data reported here, based on three levels: (i) prevention of weed stem proliferation during the cropping season with specific herbicides; (ii) elimination of the tubers after the rice crop; and (iii) reduction of the tuber‐germinating ability. 相似文献
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Plants distributed in riparian regions experience frequent episodes of flooding and drought between years, and hence, riparian plants need to be floodand drought-tolerant. Riparian plants possess various traits to survive flooding, while their sensitivity to drought has received less attention. To investigate the growth and photosynthetic responses of a riparian species (Bolboschoenus planiculmis) to flooding and drought, plants of this species were subjected to 60-d flooding or drought stress under greenhouse conditions. Growth and photosynthetic traits were measured at the end of the treatments. As well, we determined the efficiency of photosynthetic apparatus in mature leaves. Plants of B. planiculmis adequately adjusted their growth and photosynthetic traits under both flooding and drought conditions. Flooding did not affect the above-ground growth of B. planiculmis. Increased growth of roots and rhizomes and the generation of new tubers suggested a high ability of below-ground lateral growth by capturing resources under flooding conditions. Enhanced photosynthetic capacity, retained leaf pigment concentrations and chlorophyll a fluorescence capacity indicated photosynthetic adaptation to flooding. In contrast, drought significantly decreased the above-ground growth of B. planiculmis, especially the leaves, thereby minimizing water loss due to transpiration. Its increased root to shoot ratio and "phalanx" asexual propagation pattern might enhance soil water uptake ability. Although the functional leaves of B. planiculmis could retain their leaf pigment concentrations, as well as photosynthesis and chlorophyll a fluorescence, the total biomass of plants decreased, which may be a consequence of the reduced leaf area, suggesting adverse effects by drought. Therefore, both growth and photosynthetic responses of B. planiculmis are likely to contribute to the ability of this species to thrive in riparian regions, but remain susceptive to drought. 相似文献
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[Objective] The aim of this study is to clarify the competition of the absorption and accumulation of nutrients in cotton by the Bolboschoenus planiculmis (F. Schmidt) T. V. Egorova. [Method] In this experiment, the population densities of B. planiculmis were set at 0, 20, 40, 60, 80, 100 plant·m-2. The contents of phosphorus, potassium, nitrate nitrogen, soluble sugar and soluble protein in cotton seedling stage, bud stage and flowering and boll stage were detected to study the effect of population density of B. planiculmis on the nutrient absorption and accumulation of cotton. [Result] At the cotton seedling stage, when the population density of B. planiculmis was 20 plants·m-2, the soluble protein content of cotton leaves increased significiantly (P<0.05) compared with the CK, but there was no significant difference in other indicators. However, the higher population density of B. planiculmis could reduce the soluble protein content of cotton leaves and increase the soluble sugar content of cotton leaves. At the cotton bud stage, when the population density of B. planiculmis was lower than 40 plants·m-2, the phosphorus content in cotton leaves increased significantly. At the cotton boll stage, the population density of all B. planiculmis populations could reduce the content of potassium and soluble sugar in cotton leaves. When the population density of B. planiculmis was 20 plants·m-2, no significant effects were found on cotton yield. But under other population densities, the cotton yield was significantly reduced. [Conclusion] When the population density of B. planiculmis was higher than 20 plants·m-2, significant effects were found on the absorption and accumulation of cotton nutrients and cotton yield. 相似文献
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作者于1994~1996年采用田间小区试验进行了威农防除移栽稻田扁秆草施药技术研究。结果表明,威农对株高1~7cm的多年生扁秆草有强烈的杀伤和抑制作用。水稻移栽后1~10d威农第1次施用,剂量有效成分为675~90g/hm2、在此基础上,间隔15~20d再一次施用威农45~675g/hm2,可有效地防除扁秆草,总防效可达90%以上,比威农仅施用1次的防除效果提高13%以上,达到了早期消灭扁秆草的目的,对水稻安全,施药方法简单,以药土法撒施即可。 相似文献
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