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1.
以国际公认的化感水稻品种“PI312777”和非化感水稻品种“Lemont”为材料, 研究了田间旱育条件下2 种水稻的生长特性及其对水分和杂草胁迫的生理响应。结果表明, 在水分和杂草双重胁迫下, 田间水稻生长势表现为“PI312777”(旱地)＞“Lemont”(湿地)≥“PI312777”(湿地)＞“Lemont”(旱地)。进一步分析发现, 在各处理小区, 以适度干旱小区化感水稻“PI312777”叶片的叶绿素含量、保护酶活性、光合速率、水分利用效率最高,蒸腾速率最低; 以适度干旱小区非化感水稻“Lemont”叶片的光合速率、保护酶活性、可溶性糖、可溶性蛋白和水分利用效率最低, MDA 含量积累最高。与非化感水稻“Lemon”相比, 化感水稻“PI312777”对水分的利用效率更高, 有更强的适应水分缺乏的能力。 相似文献
2.
不同化感潜力水稻秧苗响应低钾的光合生理特性 总被引：4，自引：1，他引：3
本研究以化感水稻"PI312777"和非化感水稻"Lemont"为材料,采用水培方法研究低钾(5 mg K.L-1)和正常钾(40 mg K.L-1)条件下,两水稻品种的光合生理及其响应机制。结果表明,低钾条件对非化感水稻"Lemont"的根长、株高、干重有显著的抑制作用;而对化感水稻"PI312777"的根长有促进作用,对其他指标的影响较小。低钾条件下,两种水稻光合作用参数——净光合速率、胞间CO2浓度、蒸腾速率、气孔导度、气孔限制值、叶绿素含量等均下降,但非化感水稻"Lemont"下降的幅度较大,且与化感水稻"PI312777"差异显著。水稻光合作用相关酶的分析结果表明,低钾条件下核酮糖-1,5-二磷酸羧化酶、磷酸烯醇式丙酮酸羧化酶和乙醇酸氧化酶的活性及其基因表达强度均降低,但化感水稻"PI312777"的下降幅度显著小于非化感水稻"Lemont"。可见低钾条件下,化感水稻"PI312777"比非化感水稻"Lemont"具有更强的光合作用能力及耐营养匮乏能力。 相似文献
3.
不同化感潜力水稻化感效应与产量的关系 总被引：2，自引：0，他引：2
本研究探讨了连续3年5种不同化感潜力水稻田间抑草效应、产量及其之间相互关系。结果表明,不同种植时间,不同化感潜力水稻田间种植过程中伴生杂草总生物量以非化感水稻"Lemont"最大,化感水稻"PI-1"最小。化感潜力分析结果表明,不同化感潜力水稻以化感水稻"PI-1"化感抑草潜力最强,非化感水稻"Lemont"最弱。水稻产量分析结果表明,不除草条件下,不同种植时间均以化感水稻"PI-1"产量最高,非化感水稻"Lemont"产量最低。除草条件下,依然以化感水稻"PI-1"产量最高,化感水稻"IAC47"产量最小。杂草生物量、水稻化感潜力与水稻产量的相关性分析结果表明,不同化感潜力水稻产量的大小与田间杂草生物量存在极显著负相关,与化感潜力大小存在极显著正相关。 相似文献
4.
田间旱育条件下不同化感潜力水稻根际土壤酚酸类和萜类物质分析 总被引：2，自引：0，他引：2
酚酸类和萜类是水稻化感作用研究中研究较多、争议较大的2大类化感物质,但目前有关水稻根系分泌物的研究多在实验室条件下进行。本文以国际公认的强化感水稻‘PI312777’和弱化感水稻‘Lemont’为材料,以未种植水稻的土壤为对照,研究了其在田间旱育条件下,不同土壤水分状态(旱地和湿地)时,根际土壤酚酸类和萜类物质的差异。结果表明,不同水分条件下不同化感潜力水稻品种和对照根际土壤中酚酸类物质和萜类物质的组成较为相似,但各物质含量存在一定差异。适度旱胁迫下,各处理根际土壤中所检测到的咖啡酸、对羟基苯甲酸、香草酸、阿魏酸和肉桂酸5种酚酸类物质及总量均有提高,其中强化感水稻‘PI312777’根际土壤中5种酚酸类物质提高最显著,比CK湿地处理提高2.84倍;在各处理根际土壤共检测到的27种萜类物质中,17种是含氧单萜;干旱胁迫导致各处理根际土壤单萜烯、含氧单萜、含氧倍半萜和总萜变化程度和变化趋势不同,单萜烯相对含量在强化感水稻‘PI312777’根际土壤中明显提高,而在弱化感水稻‘Lemont’和对照根际土壤中则降低。本文在此基础上讨论了由此导致2种水稻田间化感抑草效果差异的原因与机制。 相似文献
5.
干旱胁迫与外源激素PDJ对不同基因型小麦化感潜力的诱导调控 总被引：2，自引：2，他引：0
盆载条件下对4个不同基因型小麦品种于播种前以外源激素PDJ(10 mg·L-1)浸种处理和返青期始干旱胁迫,测定其光合特性、水分利用和化感抗草差异.结果表明:水分胁迫(田间持水量的45%)和PDJ处理均能增强几种供试小麦的化感抗草诱导效应,两者均通过降低杂草生物量从而抑制杂草生长.水分胁迫和PDJ处理均能增强"兰考95-25"、"小偃6号"拔节期的叶片光合速率,降低气孔限制值和提高水分利用率;"豫麦66"PDJ处理下可增强光合作用而降低水分利用率,但干旱胁迫下则相反;"兰考217"经PDJ处理光合速率和水分利用率均降低.典范对应分析发现供试小麦受到干旱胁迫和外源激素PDJ处理后会引起植物形态和光合生理的变化,从而影响其化感抗草特性.小麦整体化感潜势与以杂草生物量(杂草鲜重/盆)表示的抗草指标显著相关,而小麦的整体抗草特性主要与其水分利用率、光合速率和蒸腾速率显著正相关,与植物地上生物量、株高、节间距离和气孔导度显著负相关. 相似文献
6.
不同化感潜力水稻钾离子吸收动力学差异分析 总被引：1，自引：0，他引：1
水培条件下, 采用离子耗竭法研究培养液中不同营养元素对化感水稻“PI312777”和非化感水稻“Lemont”钾离子吸收能力的影响, 并分析两水稻品种根部钾离子吸收相关基因的差异表达。结果表明, 不同处理下, 化感水稻“PI312777”相对于对照的△Km、-△Imax 和△Cmin 变化范围均较小, 与非化感水稻“Lemont”相比差异达显著水平。不同处理下, 两水稻品种的Km 值和Cmin 值的变化趋势为完全营养液培养未饥饿处理水稻(KControl)>完全营养液培养饥饿处理水稻(KAll)>只含N、P、K 的营养液培养饥饿处理水稻(KNPK)>只含N、K 的营养液培养饥饿处理水稻(KNK)>只含P、K 的营养液培养饥饿处理水稻(KPK)>无N、P、K 的完全营养液培养饥饿处理水稻(KOther)>只含K 的营养液培养饥饿处理水稻(KK), 最大吸收速率Imax 值则相反。可见, 不同营养元素对两水稻钾离子吸收存在显著影响, 其中N 素的影响高于P 素, P 素高于其他元素。水稻根部钾离子吸收相关基因的差异表达分析结果显示, 不同处理条件下两水稻品种钾离子吸收相关基因均上调表达, 但非化感水稻“Lemont”的表达强度高于化感水稻“PI312777”。可见, 非化感水稻“Lemont”响应环境因素变化的敏感度高于化感水稻“PI312777”。 相似文献
7.
不同化感潜力水稻品种对低钾的生理与分子响应 总被引：3，自引：2，他引：1
选择国际公认的化感水稻品种“P1312777”和非化感水稻品种“Lemont”为材料,在K元素为5mg·L^-1（低K）和40mg·L^-1（正常K）2个水平的营养液中培养,通过水稻形态学指标（根长、株高、根冠比和生物量）、生理生化指标（SOD、POD、CAT、根系活力及植株中N、P、K含量）,评价不同化感潜力水稻品种对低K胁迫的生理响应,并采用实时荧光定量PCR（Realtime Fluorescent Quantitative PCR,FQ-PCR）,分析了低K胁迫下水稻根和叶中与N、P、K吸收利用相关的12个关键酶的基因表达差异。结果表明,低K促进了化感水稻“P1312777”根的生长,根冠比加大,生物量增加,但对株高的影响不显著;而该条件下非化感水稻“Lemont”的上述指标均受到不同程度的抑制。低K对两种水稻的保护酶系（SOD、POD、CAT）和根系活力均有一定程度的抑制作用,植株中N、P、K含量降低,但非化感水稻“Lemont”受抑制的程度远大于化感水稻“P1312777”。FQ-PCR检测结果表明,低K胁迫下两种水稻根、叶中的12个关键酶的基因均呈现上调表达,而化感水稻“P1312777”的基因表达上调倍数均明显大于非化感水稻“Lemont”。低K胁迫下两种水稻品种的形态学差异、生理与分子响应均表明,化感水稻“P1312777”比非化感水稻“Lemont”具有更强的适应K匮乏的能力。 相似文献
8.
营养匮乏和伴生杂草是水稻种植过程中的常见影响因素。本研究应用抑制消减杂交(SSH)技术,分别研究低氮、稗草条件下,非化感水稻品种"Lemont"的上调表达基因。结果显示,低氮条件下,"Lemont"水稻中参与生长调控的生长素响应蛋白,参与抗逆防御的类NBS-LRR蛋白、过氧化氢酶、金属硫因蛋白,以及参与蛋白质代谢相关蛋白的编码基因上调表达。稗草共培下,编码NADH脱氢酶、细胞色素氧化酶、ATP依赖性RNA解旋酶等与植物生长相关的基因,与抗逆防御相关的几丁质酶和糖基水解酶基因,以及与信号转导相关的锌指蛋白及组氨酸激酶基因增强表达。研究结果表明,非化感水稻"Lemont"能够通过调节抗逆以及生长调节相关基因的表达,从而响应不同的胁迫。 相似文献
9.
尽管基因工程技术可以增加作物产量, 但转基因作物是否对农田生态产生影响受到广泛关注。本研究通过田间定位试验, 应用群落生态学方法研究了转CryIAb基因抗虫水稻"Mfb"连续2年在传统栽培和半野生条件下对稻田杂草群落组成及多样性的影响。调查结果显示: 转CryIAb基因稻"Mfb"与非转基因稻"明恢86"田间杂草种类没有显著差异。稻田杂草的频度和密度与栽培方式有关, 半野生稻田杂草的频度和密度显著高于传统稻田, 但相同栽培条件下, 转基因稻"Mfb"与非转基因稻"明恢86"田间杂草频度和密度在整个生长期内均无显著差异。半野生稻田物种丰富度(Sr)指数明显大于传统稻田; 相同栽培条件下, 相同生长时期抗虫转基因水稻"Mfb"与其非转基因对照"明恢86"对稻田杂草群落丰富度的影响差异不显著。稻田杂草群落优势度(D)、均匀度(J)以及多样性(H)各处理、各生长时期内转基因稻与非转基因稻相比均没有显著差异。稻田杂草Shannon-Wiener多样性指数变化无明显规律, 相同栽培方式相同生长期的抗虫转基因水稻"Mfb"与其非转基因对照"明恢86"的Shannon-wiener指数差异不显著。综合上述分析, 转CryIAb基因抗虫稻对稻田杂草群落的组成及多样性没有显著影响。 相似文献
10.
浮萍覆盖对稻田杂草群落组成及多样性的影响 总被引：1，自引：0，他引：1
在农业可持续发展的背景下,稻田杂草防控需要兼顾生物多样性的保护。为了解浮萍覆盖对稻田杂草群落组成及物种多样性的影响,运用群落生态学的方法,研究了多根紫萍覆盖(SP)、少根紫萍覆盖(LP)和不投放浮萍(CK)3种处理下稻田杂草发生量和群落多样性在水稻4个生育期(分蘖期、孕穗期、扬花期和成熟期)的动态变化,并对水稻产量进行分析。结果表明:SP和LP处理在前两生育期分别比CK显著降低杂草密度60.3%～75.8%和81.1%～90.4%,在整个水稻生育期能分别降低杂草鲜重生物量48.0%以上和81.3%以上,杂草群落中阔叶类杂草比例明显下降。不同处理下,稻田最主要杂草类别均是莎草科杂草;不同处理的杂草群落中重要杂草的种类和相对重要程度都有较大差异,SP和LP处理重要值较高的杂草均为莎草科的萤蔺和碎米莎草,CK处理重要值较高的杂草则为阔叶类的鸭舌草;在多数生育期,两种浮萍覆盖下的杂草群落的Margalef丰富度指数、Shannon-Wiener多样性指数和Simpson优势度指数均与CK无显著差异。SP和LP处理水稻的每穗粒数和穗重均有不同程度显著提高, SP处理的水稻产量显著提高28.0%。综合上述分析,稻田投放初始覆盖面积70.0%的多根紫萍和少根紫萍都能在降低稻田杂草密度和生物量的同时维持杂草群落的多样性,且多根紫萍覆盖能促进水稻产量增长,对保护稻田生物多样性和促进农业可持续发展有重要意义。 相似文献
11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响 总被引：2，自引：2，他引：0
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
12.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
13.
I.L. Boyd 《Biological conservation》2010,143(7):1664-1674
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options. 相似文献
14.
Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage 总被引：1，自引：0，他引：1
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate. 相似文献
15.
《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
16.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献
17.
Yoav Bashan Bernardo Salazar Ma. Esther Puente Macario Bacilio Robert Linderman 《Biology and Fertility of Soils》2009,45(6):585-594
To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse
trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus
were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB;
the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons
reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened
later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons
growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants,
no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi,
enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant.
In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after
30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination
only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity
to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as
compost or PGPB can either amplify the effect or else attenuate it. 相似文献
18.
Grete Skrede Berit Karoline Martinsen Anne-Berit Wold Stein-Erik Birkeland Kjersti Aaby 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):193-208
Abstract A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species. 相似文献
19.
Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value. 相似文献
20.
Several commercial fungicide seed treatments were evaluated for their possible effect on the survival of Bradyrhizobium japonicum on seeds and on the nodulation and yield of soybeans in a greenhouse and a field experiment. quinolate Pro (carbendazim and oxine copper), Vitavax 200FF (carboxin and thiram), and Monceren (pencycuron) had a small effect or no effect on the survival of B. japonicum and on the nodulation and yield of soybeans. They can thus be considered compatible with soybean seed inoculation. Germipro UFB (carbendazim and iprodione), Apron 35J (metalaxyl), and Tachigaren (hymexazol) decreased B. japonicum survival and the nodulation and yield of soybeans and thus cannot be considered compatible with soybean seed inoculation. 相似文献