不同密度杂草稻对水稻生长和产量的影响
毕业论文关键词:杂草稻；水稻；根系形态；土壤养分；土壤酶活性
The Influence of Different Density Weeds Rice on Growth and Yield of Rice
Abstract：Using Nanjing 44 rice as the experimental material, the author has studyed the changes of some index factors, such as the activities of soil enzymes (urease, invertase), condition of root soil (such as total nitrogen, total phosphorus, nitrogen, pH), root morphology (root length, root diameter, root dry weight, root surface area and root volume), rice dry matter accumulation (shoot dry weight, root dry weight) and yield by making the different densities of weedy rice (0 strain [CK], 4 strains, 8 strains, 12 strains, 16 weedy rice strains /m2). The results showed:with the increase of the density of weedy rice, dry matter weight of rice was decreased, the data of rice root morphology parameters also had a downtrend, so do the organic matter concentration and enzyme activities of soil. Moreover, the rice yield was reduced sharply ,which suggests that when rice and weedy rice are in symbiosis, with the rise of the density of weedy rice, rice plants are greatly affected in terms of the physiological and biochemical effects and nutrient absorption of the root system, which will restrain the normal growth of rice, and finally result in significant decrease of rice yield.
Key words: weedy rice；cultivated rice；root morphology；soil nutrient；soil enzyme activities
目 录
摘要 1
关键词 1
Abstract 1
Key words 1
引言 1
1 材料与方法 2
1.1 供试材料 2
1.2 实验设计 2
1.3 测定项目与方法 2
1.4 数据分析方法 4
2 结果与分析 4
2.1 不同密度杂草稻与水稻共生对土壤酶活性的影响 4
2.2 不同密度杂草稻与水稻共生对土壤养分的影响 5
2.3 不同密度杂草稻与水稻共生对水稻根系形态的影响 5
2.4 不同密度杂草稻与水稻共生对干物质积累的影响 6
2.5 不同密度杂草稻与水稻共生对水稻产量的影响 7
3 讨论 7
致谢 8
参考文献 9
不同密度杂草稻对水稻生长和产量的影响
引言：
杂草稻（Oryza sativa L.）是一种发生在水稻田中，能在生长和繁殖的过程中与水稻争夺各种资源，从而危害水稻生长，且具有杂草特性的水稻。杂草稻成熟早，生长迅速，而且植株可以长得很高大，因此具有很强的生物竞争性，能与水稻争抢光照、水分和养分等资源，在水稻田中的危害相当大，甚至有追赶稗草以及千金子的趋势。而且杂草稻的发生范围非常广，在全球种植水稻的地区几乎都有发生。这几年，在我国东部、南部、东北部以及中部的很多水稻种植区域，杂草稻发生有着加重的趋势，越来越严重地影响水稻的生长，可能会导致整体水稻产量的下降，威胁着我国的粮食供给[1][2]。杂草稻的不断蔓延严重影响水稻产量及稻米品质，正成为轻简化稻作技术的关键问题[3]。