论文部分内容阅读
以‘南粳9108’(粳稻)为材料,自移栽至成熟期分别与无芒稗、西来稗和光头稗共培养,以无稗草共培为对照,观察不同种类共培稗草在不同施氮水平下(0、120、240、360kg N·hm~(-2)对水稻产量形成的影响.结果表明:相同氮肥水平下,不同种稗草株高表现为西来稗>无芒稗>光头稗,生育期由长到短为无芒稗>西来稗>光头稗.随着氮肥施用量的增加,不同种稗草的生物量在240 kg N·hm~(-2)下达到最大值,然后降低,无芒稗和西来稗的生物量均显著高于光头稗.在0 kg N·hm~(-2)下,不同种稗草对水稻产量无显著影响;在120 kg N·hm~(-2)下,无芒稗和光头稗处理水稻产量与无稗草处理差异不显著,但西来稗处理产量较无稗草处理显著降低;在240 kg N·hm~(-2)下,无芒稗、西来稗和光头稗处理显著减产;在360 kg N·hm~(-2)下,无芒稗和西来稗处理产量较无稗草处理显著降低,光头稗处理与无稗草处理差异不显著.稗草和氮肥对水稻产量形成具有明显的互作效应.120 kg N·hm~(-2)下,西来稗处理显著降低了水稻灌浆期剑叶硝酸还原酶活性、光合速率和根系氧化力以及成熟期氮积累量和干物质量,其他稗草处理与对照差异不显著;在240和360 kg N·hm~(-2)下,无芒稗和西来稗处理降低了水稻上述指标;在0 kg N·hm~(-2)下,各处理的上述指标差异不显著.回归分析表明,稗草表型对水稻产量的影响由大到小的顺序为生物量、株高、生育期和分蘖数,推测稗草较大的生物量造成水稻剑叶光合速率、硝酸还原酶活性、根系氧化力、氮积累量和干物质积累量降低,影响了水稻的生长发育,造成水稻减产.
Using ’Nanjing Japonica 9108’ (japonica rice) as material, we cultivated barnyardgrass, barnyardgrass and barnyardgrass from transplanted to mature stage, respectively. No barnyardgrass co-culture was used as control, and different kinds of barnyardgrass The effects of 0,120,240,360 kg N · hm -2 on the yield formation of rice under different nitrogen levels were studied.The results showed that the barnyard grass plant height was barnyard grass> Echinochloa crusgalli> Echinochloa crusgalli> Echinochloa crusgalli> Echinochloa crusgalli> Echinochloa crusgalli Echinochloa crusgalli was grown at 240 kg N · hm -2 Reached the maximum and then decreased, and the biomass of barnyardgrass and barnyardgrass were significantly higher than that of barnyardgrass.Under 0 kg N · hm -2, different barnyardgrass had no significant effect on rice yield; at 120 kg N · hm -2, there was no significant difference between the treatments of barnyardgrass and barnyardgrass without rice barnyardgrass, but the yield of barnyardgrass was significantly lower than that of the barnyardgrass at 240 kg N · hm -2, (-2), barnyardgrass, barnyardgrass and barnyardgrass decreased significantly. Under barnyardgrass and barnyardgrass treatments, barnyard grass and barnyardgrass significantly decreased at 360 kg N · hm -2, Difference between barnyard grass treatment and barnyard grass treatment is not Echinochloa crusgalli and nitrogen fertilizer had obvious interaction effects on rice yield formation.When the barnyardgrass was dropped under 120 kg N · hm -2, the nitrate reductase activity, photosynthetic rate and root system Oxidative stress, nitrogen accumulation and dry matter at maturity, but no significant difference between the other barnyardgrass treatments and the control. The treatment with barnyardgrass and barnyardgrass at 240 and 360 kg N · hm -2 reduced the above indexes ; Under the condition of 0 kg N · hm -2, there was no significant difference among the above indexes for each treatment.Regression analysis showed that the effect of barnyardgrass phenotype on rice yield was in order of biomass, plant height, fertility Period and tiller number. It was speculated that the larger biomass of barnyardgrass caused the decrease of photosynthetic rate, nitrate reductase activity, root oxidation, nitrogen accumulation and dry matter accumulation in rice leaves, which affected the growth and development of rice and reduced the yield of rice.