摘要
【目的】比较种植密度和单播、混播种植方式对大豆超高产品种和普通品种根系形态和活力的影响。【方法】于2012和2013年在盆栽条件下,研究不同种植密度和单混种植处理对超高产品种辽豆14、中黄35和普通品种辽豆11根系形态、根系活力和伤流成分的影响。采用随机区组试验设计,种植密度设3个水平(3株/盆、6株/盆和9株/盆),2个种植类型(单一种植方式:各品种单播;混合种植方式:同一盆中各品种按1﹕1种植)。在大豆的开花期(R2)、鼓粒中期(R6)和生理成熟期(R8)取样,将根系从土中取出,反复冲洗,利用根系扫描仪Win Rhizo Program(Re.gent Instruments Inc.Canada)对样根进行扫描测量,测定单株总根长、根表面积和根体积;根系活力用TTC法(甲醇浸泡法)测定;伤流液用重量法收取;伤流液中的磷用钼酸铵比色法测定(UV-2450),钾用火焰光度计(PEAA800)测定,可溶性糖用蒽酮法测定;由超高产品种在混播、单播处理下根系性状的比值除以普通品种在混播、单播处理下根系性状的比值得到超高产品种相对于普通品种的根系竞争比率(RCR),RCR>1表示超高产品种比普通品种的根系竞争力强。【结果】超高产品种和普通品种大豆的根系形态性状、根系活力和伤流成分在密度和种植方式间均存在显著差异。整个生育期,不同品种大豆的根系形态性状和根系活力均在鼓粒期达到最大,伤流量和伤流成分的最高值则出现在开花期。鼓粒期至成熟期,超高产品种的单株根长、根体积普遍高于普通品种,单播和混播处理下,分别较普通品种高出8.2%、10.4%和53.9%、34.6%。超高产品种的根系活力较强,而且具有较高的伤流量和伤流成分,3种密度水平下,超高产品种的平均伤流量分别高出普通品种16.9%、42.0%和49.1%。超高产品种的根系竞争比率普遍高于普通品种。随密度的增加,超高产品种和普通品种的单株根表面积和根体积下降,其中普通品种的下降幅度更大,达50.9%和50.7%。混播时超高产品种与普通品种的根系活力差异随密度的增加而增大;超高产品种相对于普通品种的根系竞争比率也提高,由平均1.00增至1.63,其中6株/盆处理下根系竞争比率增幅达到显著水平。6株/盆和9株/盆的种植密度下,超高产品种的单株籽粒产量高于普通品种,混播时差异达显著水平;随密度的增加,超高产品种和普通品种的单株生物量和籽粒产量下降,其中普通品种的下降幅度更大,达62.5%和60.0%;大豆根系形态性状、根系活力与单株生物量和籽粒产量呈显著或极显著正相关。【结论】超高产品种在密植条件下根系更发达,具有较强的根系吸收能力、竞争力和较高的物质生产力。
[Objective]Root absorbing ability of soybean is closely related to the yield, while the response of soybean cultivars to seeding rates is not the same. Two pot experiments were conducted to find out the root morphological traits and root vigor of super-high-yield soybean cultivars, and common cultivar under the treatments of different seeding rates and planting pattern.[Method]Two super-high-yield soybean cultivars Liaodou 14, Zhonghuang 35,and one common cultivar Liaodou 11 were used in the pot experiments to investigate the effects of different seeding rates and planting patterns on soybean root morphological traits, root vigor and bleeding component in 2012 and 2013. The experiment was laid out in a randomized block experiment design with five replications. The treatments consisted of three levels of seeding rate (3, 6 and 9 plants/pot) and two planting patterns (single seeding and mixed seeding). At the stages of R2, R6 and R8, plant roots were selected for measurements. Root length, root surface and root volume were measured by root system scanner WinRhizo Program (Re.gent Instruments Inc.Canada).Root vigor was estimated by TTC method. Bleeding was collected by gravimetric method. The bleeding phosphorus, potassium and soluble sugar were, respectively, determined by molybdenum stibium anti (UV-2450) , flame photometer (PEAA800) and glucose oxidasedetection. Root competition ratio (RCR) of super-high-yield cultivar was calculated by the root character of super-high-yield cultivar at mixed seeding to those at single seeding ratio divided the root character of common cultivar at mixed seeding to those at single seeding ratio. RCR>1 means that competitiveness of super-high-yield cultivar was stronger.[Result]The result showed that the root morphological traits, root vigor and bleeding components varied with different seeding rates and planting patterns. The whole growth stage, the root morphological traits, root vigor, and the bleeding sap reached maximum at seed filling stage and flowering stage, respectively. Super-high-yield cultivars had higher root length, root volume, root vigor, bleeding sap and bleeding components than those of common cultivar from seed-filling stage to maturity stage. The root length and root volume of super-high-yield cultivar were 8.2% and 10.4%, 53.9% and 34.6% higher than those of common cultivar, respectively, under single seeding and mixed seeding treatments. For another, the bleeding sap of super-high-yield cultivars was 16.9%, 42.0% and 49.1% higher than those of common cultivar at different densities. On the other hand, the root competition ratio of super-high-yield cultivar was higher as well. The root surface and root volume per plant of two cultivars were declined with seeding rates increased, especially the common cultivar which declined about 50.9% and 50.7%. With seeding rates increased the difference of root vigor between super-high-yield cultivar and common cultivar was added, and also the root competition ratio which increased from 1.00 to 1.63. The seed weight per plant of super-high-yield soybean cultivars was higher than that of common cultivar at 6 plants/pot and 9 plants/pot treatments, especially at mixed seeding. The biomass and seed weight per plant of two cultivars were declined with seeding rates increased, especially the common cultivar which declined by 62.5% and 60.0%. There existed significant positive correlation between root morphological characters, root vigor and biomass, seed weight per plant.[Conclusion]The research indicated that super-high-yield soybean had expanded root system under appropriate seeding rate, which maintained stronger absorption capacity and compatibility.
出处
《中国农业科学》
CAS
CSCD
北大核心
2015年第6期1084-1094,共11页
Scientia Agricultura Sinica
基金
国家自然科学基金(31071355
31171570)
辽宁省科技厅攻关项目(2011201020)
国家"十一五"科技支撑计划(2011BAD35B06-2)
关键词
大豆
密度
根系形态
根系活力
伤流成分
soybean
density
root morphology
root vigor
bleeding component