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玉米穗粒腐病研究概况 总被引：2，自引：0，他引：2
玉米穗粒腐病是一种世界性病害,发生比较普遍,危害极其严重。一般品种发病率为5%~10%,感病品种发病率可达50%左右,可造成严重损失。该病害已成为玉米生产上存在的突出问题。1988年美国玉米穗粒腐病大流行,引起了各国的高度重视,继而掀起了一系列对玉米穗粒腐病原菌的研究工作。1997年印度的迈哥哈拉雅州严重发生玉米穗粒腐病,造成毁灭性危害,所有的栽培品种都同样感病,25%以上的玉米穗被严重侵染。病原菌侵染玉米果穗,引起籽粒腐烂,严重影响玉米的品质和降低玉米的产量,而且部分病原菌分泌的毒素可对人畜产生严重的毒副作用,引起人畜的中毒… 相似文献
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玉米镰孢穗腐病发生条件及化学防治效果研究 总被引：2，自引：1，他引：1
通过人工接种筛选抗病品种资源,研究播期、种植密度对病害发生的影响,明确玉米镰孢菌穗腐病发生与品种资源、播期、种植密度的关系,分析棘孢木霉菌颗粒剂(TCF)和XDS种衣剂(40%毒死蜱乳油、20%辛硫磷和10%井岗霉素混剂)对玉米穗腐病的防效。结果表明,32个自交系中有6个抗病自交系,延迟播种玉米镰孢菌穗腐病发生严重,播种密度对病害发生程度无显著影响。人工接种条件下,TCF颗粒剂穴施、XDS种衣剂拌种2个处理表现为百粒重增加、秃尖长度降低,TCF颗粒剂穴施处理的防效最高,为48.69%。 相似文献
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玉米穗腐病是玉米生长后期的重要病害之一,又称玉米穗粒腐病,属世界性病害。一般品种发病率为5%～10%,感病品种发病率可达50%左右,造成严重损失。
1玉米穗腐病的诊断 相似文献
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根据田间调查和病原菌鉴定,明确了河西走廊玉米穗粒病是由8种病原菌复合侵染所致。其中Fusariummoniliforme和F.graminearum共同组成了玉米穗粒腐病的优势菌种。探明了玉米穗粒腐病的发生与品种抗性、环境条件、种植密度、施肥量及虫害之间的关系。 相似文献
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水稻穗腐病病原分离、鉴定及生物学特性 总被引：2，自引：1，他引：2
水稻穗腐病（rice spikelet rot disease,RSRD）是近年上升较快的一种水稻穗部重要病害,影响水稻产量和稻米品质。从稻穗发病谷粒中,共分离到4种真菌,经形态学、生物学及分子生物学鉴定,分别为层出镰刀菌（Fusarium proliferatum）、澳大利亚平脐蠕孢菌（Bipolaris australiensis）、新月弯孢菌（Curvularia lunata）和细交链孢菌（Alternaria tenuis）。4种病原菌均能在温度4℃~40℃、pH 3~12条件下生长,最适的温度范围是25℃~30℃,不同菌最佳产孢的pH值差异较大。4种菌均能在供试的碳、氮源培养基上生长,不同的碳、氮源对各菌的菌丝生长和产孢的影响不同。穗腐病是由多种病原菌引起的水稻后期穗部褐变病害,病原菌具有多样性、复杂性和致病性分化的现象。 相似文献
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Yield formation of CO2-enriched hybrid rice cultivar Shanyou 63 under fully open-air field conditions 总被引：1，自引：0，他引：1
Hongjiang Liu Lianxin Yang Yulong Wang Jianye Huang Jianguo Zhu Wang Yunxia Guichun Dong Gang Liu 《Field Crops Research》2008,108(1):93-100
Hybrid indica rice (Oryza sativa L.) cultivars play an important role in rice production system due to its heterosis, resistance to environmental stress, large panicle and high yield potential. However, no attention has been given to its yield responses to rising atmospheric [CO2] in conjunction with nitrogen (N) availability. Therefore we conducted a free air CO2 enrichment (FACE) experiment at Yangzhou, Jiangsu, China (119°42′0′′E, 32°35′5′′N), in 2004–2006. A three-line hybrid indica rice cv. Shanyou 63 was grown at ambient and elevated (ca. 570 μmol mol−1) [CO2] under two levels of supplemental N (12.5 g Nm−2 and 25 g Nm−2). Elevated [CO2] had no effect on phenology, but substantially enhanced grain yield (+34%). The magnitude of yield response to [CO2] was independent of N fertilization, but varied among different years. On average, elevated [CO2] increased the panicle number per square meter by 10%, due to an increase in maximum tiller number under enrich [CO2], while productive tiller ratio remained unaffected. Spikelet number per panicle also showed an average increase of 10% due to elevated [CO2], which was supported by increased plant height and stem dry weight per tiller. Meanwhile, elevated [CO2] caused a significant enhancement in both filled spikelet percentage (+5%) and individual grain weight (+4%). Compared with the two prior FACE studies on rice, hybrid indica rice cultivar appears to profit much more from elevated [CO2] than japonica rice cultivar (ca. +13%), not only due to its stronger sink generation, but also enhanced capacity to utilize the carbon sources in a high [CO2] environment. The above data has significant implication with respect to N strategies and cultivar selection under projected future [CO2] levels. 相似文献
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Rice blast disease is one of the obstacles of rice production not only in Japan but throughout rice producing countries. The effects of fan-forced wind on the incidence of rice blast disease were studied in two successive seasons. Electric fans (5 KW, 110-cm blade diameter) set on the ridge of paddy fields at a height 5 m from the ground level were used to artificially generate wind. In season 1, the fan operated twice daily for 30 min periods at 11:00 pm and 4:00 am from June 15 to September 1. The blocks of the paddy fields were divided into 6 zones according to wind speed and distance from the fan. The wind speed ranged from 2.0 to >7.3 m/s. The incidence of both rice leaf and panicle blast was significantly lower in the zones receiving wind between 2.6 and 7.3 m/s; however, the zone that received a velocity >7.3 m/s was severely affected by leaf and panicle blast. The zone that received the a wind speed of 2.6 m/s or lower exhibited an inefficient reduction of leaf and panicle blast disease, but it was better than in the control fields. In season 2, a wind-forced fan was applied from June 16 to September 9, with the velocity adjusted between ca. 3.0 and 6.0 m/s. The incidence and severity of leaf and panicle blasts (chuff, rachis-branch and neck blast) were efficiently reduced in the wind-treated fields. Fan-forced wind was more effective than the application of conventional chemical fungicides for controlling rice blast disease. These data demonstrate the potential of fan-forced wind for controlling rice blast disease. 相似文献
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目的 旨在确立稳定高效的水稻穗腐病人工接种技术,鉴定不同菌株致病力。利用已有的伏马菌素检测方法分析测定两种培养基中不同菌株的伏马菌素合成能力,基于上述方法筛选强致病力高产伏马菌素菌株。方法 分别在水稻孕穗期和抽穗期采用注射法和喷雾法接种,观察不同时期、不同接种方法下层出镰刀菌的致病性和稳定性;利用适合的接种方法和液相色谱-串联质谱检测法比较不同菌株的致病力和产毒能力。结果 在花粉母细胞减数分裂期-花粉母细胞成熟期采用注射法接种水稻穗腐病,发病率较高且稳定;在花粉母细胞形成期-始穗期接种对水稻产量影响较大。基于该方法成功筛选出了强致病力菌株FP4、FP6、FP8、FP9、FP10;经HPLC-MS/MS分析测定了层出镰刀菌产生伏马菌素能力,获得了强致病力高产毒菌株FP4和FP9。稻谷培养基比玉米培养基更适合层出镰刀菌合成伏马菌素。结论 水稻穗腐病初侵染为花粉母细胞形成期-花粉母细胞减数分裂期,最佳侵染时期为花粉母细胞形成期-齐穗期;穗腐病对水稻产量的影响与感病时期密切相关。 相似文献
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Kazuyuki Tanno 《Grass and Forage Science》2020,75(3):326-338
Cultivation of forage rice for whole-crop silage has been increasing in Japan and will be important in Asia. In this study, effects of cultural practices on growth and yield of a forage rice cultivar “Tsukisuzuka” having short panicle 1 allele were analysed quantitatively using linear mixed model. The contribution of basal dressing to dry yield per 1 g/m2 nitrogen fertilizer was larger than that of topdressing. In addition, topdressing 30 and 20 days before heading was considered to have the disadvantage of increasing risk of lodging and panicle weight respectively. Effects of weather elements on growth of forage rice were also speculated. In tested fields, high solar radiation at seedling and tillering stage was considered important for the high yield. As the number of continuous cropping cycles increased, growth of forage rice got worse. And application of compost improved growth of forage rice. Elemental analysis of soil and plants revealed that this continuous cropping obstacle was likely to attributed to deficiency of potassium. In addition, potassium deficiency increased panicle weight of a forage rice cultivar having short panicle 1 allele. Therefore, control of potassium nutrition will be useful for both sustaining productivity (sufficient application of potassium) and seed production (restriction of potassium). These findings will be useful for improvement of cultivation method of forage rice. 相似文献
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In water-efficient rice production, grain yield is often constrained by panicle size. The objective of this study was to genetically dissect the response of panicle morphology to irrigation regimes in aerobic rice culture. We grew ‘Akihikari’ (a lowland japonica cultivar) × ‘IRAT109’ (an upland japonica cultivar) backcross inbred lines in aerobic soils with full or limited irrigation for 2 years, and examined 4 panicle traits—number of florets per panicle (FPP), number of primary branches per panicle (BPP), number of florets per primary branch (FPB), and frequency of pre-flowering floret abortion (%FA)—and grain yield. QTLs for BPP were detected in both the irrigation regimes but QTLs for FPB and %FA were detected mostly only in either of the irrigation regimes. The QTL for FPP on chromosome 2 (RM3421–RM213) coincided with that for yield under full irrigation, showing that this QTL is related to sink capacity and yield potential in aerobic rice culture. On the other hand, the QTL for FPB on chromosome 1 (RM3148–RM243) coincided with that for yield under limited irrigation, when water deficit was moderate. The QTL for root axis length at vegetative stage, previously identified in the same mapping population, was located near this region. This study unravelled the complicated genetic control on panicle morphology in aerobic rice culture, and suggested the positive roles of the dehydration avoidance mechanism by vigorous root growth on panicle size and yield under dry soil conditions. 相似文献
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褐飞虱为害对水稻产量结构影响的研究 总被引：7，自引：0，他引：7
采用标准虫态分期连续接虫方法，研究了褐飞虱为害对水稻产量结构的影响。结果表明，褐飞虱为害可造成水稻有效穗数和实粒数减少，千粒重下降，并皆最终导致产量降低。分蘖期是穗数减少的敏感生育朝；灌浆开始以后为影响千粒重的敏感生育期。褐飞虱为害早期需达到较大的虫口数量才能造成水稻有效穗数和实粒数显著减少。灌浆期水稻只要遭受一定虫量为害即可引起千粒重显著下降，相同虫量下不同起始受害时间及同生育期稻株不同虫量造成的损失均有显著差异，水稻被害时间越早、受害时间越长、虫量越多，造成的产量损失越大。 相似文献
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A field experiment was conducted to investigate the impact of simulated rat damage on grain yield in irrigated lowland rice in An Giang province, in the Mekong Delta of Vietnam. Rat damage was simulated by making a 45° cut at the base of the rice tillers about 3–5 cm above the soil surface. 0% (control), 5%, 10%, 25% and 50% of the tillers were removed at the tillering (25 days after sowing, DAS), panicle initiation (43 DAS), flowering (72 DAS) and ripening (87 DAS) stages. The total number of mature tillers, immature tillers and percent filled grains, the weight of 1000 grains and grain yields were recorded. The rice crop completely compensated by increased tillering and yield for tillers damaged up to 50% at the tillering stage. However, the damage and yield loss were highly variable. The ability of the rice crop to compensate at later stages progressively reduced. The implications for managing rat damage to rice crops are (1) rodent control activities should be applied before 10% of tillers are damaged at the tillering stage, and (2) a well balanced nitrogen supply during the tillering stage could potentially assist the rice plants to better compensate for rat damage. 相似文献
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通过对水稻只施基肥和穗肥的深施施肥试验研究,结果表明:深层施肥法可提高肥料利用率25%,增加水稻有效分蘖和成穗率,增加产量10%以上,节省人工,并避免贪青晚熟,减轻病害。 相似文献
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对直立穗型与弯曲穗型水稻不同生育时期干物质生产转运进行对比分析。结果表明,两种穗型水稻苗期充实度差异达显著水平,直立穗型高于弯曲穗型;营养生长期直立穗型干物质积累有高于弯曲穗型水稻的趋势;两种穗型水稻茎鞘输出率截然相反,弯曲穗型输出而直立穗型却有积累;两种穗型水稻抽穗后的干物质积累对产量的贡献率都大于85%,直立穗型水稻后期贡献大于弯曲穗型,且均超过90%;直立穗型水稻抽穗前干物质转运率低于弯曲穗型。 相似文献