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论湖南水稻育种的主攻方向和技术策略 总被引：1，自引：0，他引：1
《杂交水稻》2015,(4)
当前中国水稻产业处在转型期,转型的方向是经营规模化、农民专业化、服务社会化、全程机械化、栽培轻简化。为了适应这种转变,湖南水稻育种应重点开展如下5个方面的工作:(1)主攻早、中熟期的双季稻育种,以适应双季稻面积和直播栽培面积扩大对短熟期品种的需求;(2)培育低镉、高直链淀粉含量的双季稻品种,以提高稻米健康品质;(3)培育苗期耐5℃低温的早稻和开花期耐17℃低温的晚稻,以防止倒春寒、寒露风对直播双季稻的危害;(4)利用粳稻和爪哇稻资源以及非典型亚种间杂种优势,以提高双季稻产量潜力;(5)重点储备抗螟虫、抗除草剂的转基因水稻技术,以迎接转基因水稻时代的到来。 相似文献
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我国双季稻生产机械化制约因子与发展对策 总被引：29，自引：0，他引：29
20世纪70年代中期以来,我国双季稻种植面积占水稻总面积比例持续下降,从当时的71%下降到近年的40%左右。按单位土地面积计算,双季稻早晚两季产量比单季稻高57%左右,改单季稻为双季稻种植,在保持稻田面积不变情况下,可大幅提高种植面积和总产。双季稻种植面积下降的主要原因是机械化程度较低,生产效益不高。制约双季稻全程机械化的关键是机插秧比例不高,特别是双季稻机插秧季节紧张,适宜机插搭配品种少,机插质量较差,及主要作业环节机械化不配套等。发展双季稻生产全程机械化的关键途径是:选育和筛选一批适宜双季稻机械化生产的品种,优化双季稻机械化生产的品种搭配布局;创新一批双季稻机械化生产模式,完善关键环节技术模式;创制一批双季稻机械化生产的机械装备,实现机具装备配套;研发一批双季稻全程机械化栽培技术,推进农机农艺技术配套与应用。 相似文献
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武冈市龙田乡德胜村是一个纯双季稻种植区。全村有水田７８７ｈｍ２，常年双季稻面积６５ｈｍ２左右。１９８６年前，该村早稻单产均高于晚稻。自１９８７年起，由于普及了杂交晚稻，逐步推广了“双两大”栽培，晚稻连年丰收。而早稻仍以常规品种为主，加之生长期间自然... 相似文献
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邵阳市是一个人多地少,粮食供需矛盾较为突出的地区,人平占有粮食仅340kg左右,远低于全省平均水平。为了解决粮食问题,1986年以来,我市在吨粮田开发中,麦类——双季稻三熟制面积逐步扩大,成为亩产过吨粮的主要栽培模式之一。 相似文献
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随着吨粮田开发的深入,新郡县麦类—双季稻近年来发展较快,已成为该县双季稻田中占重要地位的耕作制度。1991年全县1.7万ha双季稻田,种植麦类—双季稻0.53万ha,占双季稻田的31.4％,过吨粮面积0.46万ha,占全县双季稻田过吨粮面积的67％,其中有严塘、高桥、土桥、酿溪4个成建制乡(镇),0.19万ha双季稻田亩产过吨粮。 相似文献
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龙海市是我国著名的水稻高产和粮食生产大县沛），1998年双季稻平均单产达1002kg（单产面积为666．7m2，下同）。百尺竿头如何更进一步？必须认真地总结过去的经验，找出现存的主要问题，开拓进一步发展的途径。1龙海市水稻产量节节上升的主要经验龙海市1949年双季稻单产... 相似文献
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浙江省永康市在优化粮田种植结构的探索中，进行了“冬季蔬菜雪里蕻(雪菜)-春马铃薯-双季稻”一年四熟制试验，面积6．3亩，生产效果很好。 相似文献
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《Journal of Crop Improvement》2013,27(1-2):33-52
SUMMARY Cropping system refers to temporal and spatial arrangements of crops, and management of soil, water and vegetation in order to optimize the biomass/agronomic production per unit area, per unit time and per unit input. Soil quality refers to its intrinsic attributes that govern biomass productivity and environment moderating capacity. It is the ability of soil to perform specific functions of interest to humans. Three components of soil quality (e.g., physical, chemical and biological) are determined by inherent soil characteristics, some of which can be altered by management. Soil quality and soil resilience are inter-related but dissimilar attributes. Resilient soils, which have the ability to restore their quality following a perturbation, have high soil quality and vice versa. Decline in soil quality sets-in-motion degradative processes, which are also of three types, namely physical (e.g., compaction, erosion), chemical (e.g., acidification, salinization) and biological (e.g., depletion of soil organic matter content). Soil degradation, a biophysical process but driven by socioeconomic and political causes, adversely affects biomass productivity and environment quality. Determinants of soil quality are influenced by cropping systems and related components. Dramatic increases in crop yields during the 20th century are attributed to genetic improvements in crops, fertilizer use, and improved cropping systems. Dependence on fertilizers and other input, however, need to be reduced by adopting cropping systems to enhance biological nitrogen fixation and use efficiency of water and nutrients through conservation tillage, cover crops, and improved methods of soil structure and nutrient management. 相似文献
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《Journal of Crop Improvement》2013,27(1-2):187-216
SUMMARY Perennial and annual forage legumes are important components of sustainable cropping systems. Forage legumes are a primary source of forage to supply protein and fiber for livestock rations. They can be grazed, or stored as hay or silage. They contribute biologically fixed N and sustain the soil by reducing erosion and increasing soil organic matter levels. Diversifying cropping systems by including legumes can also reduce weed, insect, and disease incidence. Potential new uses of legumes include phytoremediation of N contaminated sites and capturing N lost from cropping systems. Legumes also have potential use as a feedstock for renewable energy production. Legumes have traditionally been used in rotation with grain crops but more recently have been shown promise as winter cover crops, intercrops with grain crops, and as living mulches. In this review, we discuss traditional and new roles of forage legumes in sustainable cropping systems with examples primarily chosen from northern USA and Canada. 相似文献
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《Journal of Crop Improvement》2013,27(1-2):125-136
Abstract The rice-wheat cropping system of the Indo-Gangetic Plains (IGP) has contributed tremendously to food security of the region. However, of late there has been a significant slowdown in yield growth rate of this system and the sustainability of this important cropping system is at stake. A decline in soil productivity, particularly of organic C and N, a deterioration in soil physical characteristics, a delay in sowing of wheat, and decreasing water availability are often suggested as the causes of this slowdown in productivity. Therefore, a paradigm shift is required for enhancing the system's productivity and sustainability. Resource-conserving technologies involving zero-or minimum tillage with direct seeding, improved water-use efficiency, innovations in residue management to avoid straw burning, and crop diversification should assist in achieving sustainable productivity and allow farmers to minimize inputs, maximize yields, conserve the natural resource base, reduce risk due to both environmental and economic factors, and increase profitability. 相似文献
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《Journal of Crop Improvement》2013,27(1-2):329-359
SUMMARY The impact of cropping systems on water quality is uncertain, and its interpretation depends heavily upon our definition of acceptable risk. As a means of determining net effect, both classical and precautionary approaches to assessing risk have their strengths and weaknesses. Relating the impact of cropping practices to human health outcomes can be particularly difficult. A variety of guidelines and standards are used to assess water quality, and recent methods for assessing water quality seek to incorporate more than water chemistry alone. An understanding of the derivation of water quality guidelines and standards is essential to their effective application, and meaningful interpretation. In addressing water quality concerns, it is essential to first clarify that there is indeed a problem, and whether agriculture makes a significant contribution. Compound interactions and modes of chemical movement can render this troublesome. Yet, because farmers live on the land and drink the water, they want to be among the first to know what is happening and to take appropriate action when problems are identified. Agriculture must be proactive in addressing water quality concerns. However, effective land management strategies depend greatly upon regional differences and may be highly site-specific. Hence, it is best to apply a set of common sense concepts at the local level. Because soil and water degradation are closely related, practices first developed to help conserve the soil (i.e., crop rotations, reduced tillage, cover crops) may also tend to conserve water quality. As well, restricting the loss of agricultural inputs (e.g., fertilizer nutrients, pesticides) from off farmland, and reducing the amount of those that might be available to do so, can assist in effectively reducing potential pollution. Buffer zones are a promising means of using plants and wetlands as a filter towards intercepting escaping contaminants. 相似文献
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稻田两种粮经型新复种方式 总被引：2，自引：1，他引：2
通过1987～1990年稻田粮经型新复种方式对比试验结果，表明了新复种方式大麦／西瓜+玉米-稻和绿肥+大麦／西瓜-稻分别比原复种方式大麦／西瓜-稻和西瓜-稻亩增粮食99.2和296.2 kg， 增收25.11元和49.93元， 提高光能利用事0.145%和0.596%。同时，分析了水、旱作茬口对晚稻的增产后效。 相似文献
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为探索正茬与迎茬种植方式对大豆根际土壤微生物群落组成的影响,分析导致大豆迎茬障碍形成的主要病原微生物,研究大豆迎茬障碍的形成机制,进而为其生物防治提供一定的理论基础,本研究采用Illumina HiSeq 2500高通量测序技术分析正茬与迎茬大豆根际土壤微生物群落组成。结果表明：大豆迎茬种植在一定程度上降低了土壤细菌群落丰度和多样性,而增加了土壤真菌群落丰度和多样性。正茬与迎茬大豆根际土壤微生物群落组成和主要优势菌群所占比例均存在较大差异。酸杆菌门(Acidobacteria)和放线菌门(Actinobacteria)分别为正茬和迎茬大豆根际土壤细菌群落中最具优势的细菌门。镰孢霉属(Fusarium)和粗糙孔菌属(Subulicystidium)分别为正茬和迎茬大豆根际土壤真菌群落中最具优势的属。 相似文献
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《Journal of Crop Improvement》2013,27(1-2):61-80
Summary Agroecology is defined as the application of ecological concepts and principles to the design and management of sustainable agroecosystems. By viewing cropping systems as agroecosystems, an understanding of the value of the emergent qualities of systems can become a guiding element in research design. A framework for applying this approach in cropping systems research in proposed. A protocol for researching the conversion to sustainable agriculture involves three levels of investigation. The first focuses on improving the efficiency of conventional farming inputs and practices in ways that reduce both their amounts and the environmental impacts of their use. The second focuses on substituting conventional inputs and practices with alternatives that meet broader environmental standards, such as certified organic. Since the problems addressed at these two levels continue to present themselves, a third level is proposed whereby the agroecosystem is redesigned so as to operate on the basis of a new set of ecological processes. At this third level, the emergent qualities of the system itself help prevent problems. Such an approach promotes the conversion to sustainability. 相似文献