武夷山天然常绿阔叶林林隙物种多样性比较研究

对武夷山不同常绿阔叶林发育阶段林隙样地更新层物种多样性变化规律研究结果表明 ,林隙物种多样性指数大于非林隙样地 ,而生态优势度则相反 ;不同大小扩展林隙物种多样性指数不同 ,<10 0m2 面积林隙物种多样性指数最大 ,而≥ 30 0m2 的林隙则最小 ;>1.5m的林隙物种丰富度指数、Shannon Wienner多样性指数、均匀度指数和均优多指数随发育阶段的变化趋势基本一致 ,均以林隙形成时间为 10～ 2 0年达最大 ,而 <10年的则最小 ;更新层树种平均各林隙内SW多样性指数、均匀度指数和均优多指数以林隙形成 10～ 2 0年为最小 ,至 30年后有所增加 ,4 0～ 5 0年时达最大 ,5 0年后呈缓慢减少趋势。林隙形成为不同树种更新提供了动力 ,林业生产适当培育林隙对物种多样性保护极其重要。     

常绿阔叶林退化生态系统恢复过程物种多样性的发展趋势与速率

常绿阔叶林退化生态系统恢复的关键是物种多样性的恢复发展。对大明山区常绿阔叶林退化生态系统植被恢复过程物种多样性的发展趋势和速度进行了研究。结果表明 :1.大明山中山区和低山丘陵区退化生态系统恢复过程中物种多样性的发展速度存在很大差异。中山区采伐森林后炼山种植杉木 ,经过 2 0年的自然恢复 ,在 60 0 m2的调查面积里出现了 178个物种 ,其中乔木层就有 58个物种 ,并且 2 0年左右就能形成以阳性阔叶先锋树种与中生性阔叶树种为共优势的森林群落 ,大约 60～ 10 0年就能形成中生性的常绿阔叶林。而在低山丘陵区 ,常绿阔叶林退化生态系统恢复过程物种多样性的发展速度相当缓慢 ,恢复期为 2 0～ 30年的群落 ,在 4 0 0 m2 样地上仅出现 2 2个物种 ,乔木层只有 3个物种 ;而且由于人为的干扰不断 ,这一地区的马尾松林很难恢复到地带性的常绿阔叶林 ,只能发展成相对长期稳定的人为偏途顶极。 2 .在退化生态系统的恢复过程中 ,物种数量的变化呈前期迅速增加 ,中期减少 ,后期维持一定水平的发展趋势。 3.单位面积上个体数量的变化在群落的不同层次表现不同 ,乔木层在 1～ 2 0年间个体数量呈递增趋势 ,2 0年后表现为递减趋势 ;灌木层的个体数呈不断增长的趋势 ;而草本层的个体数量则呈非线性发展。4 .β     

杭州西湖山区不同植被类型植物多样性比较研究

对杭州西湖山区常绿阔叶林(EBLF)、落叶阔叶林(DBLF)和针叶阔叶混交林(NBLMF)3种植被类型的群落多样性指数进行比较.结果表明:落叶阔叶林具有较高的物种多样性,针叶阔叶混交林物种多样性较低;在垂直结构物种多样性比较中,常绿阔叶林和针叶阔叶混交林为灌木层>乔木层>草本层,而落叶阔叶林为灌木层>草本层>乔木层;枯立木在常绿阔叶林中主要存在于6～10 m高度,而落叶阔叶林和针叶阔叶混交林中主要存在于3～4 m高度.与其他各地植被类型相比,常绿阔叶林和落叶阔叶林群落物种多样性随纬度增加而减少.     

元阳梯田全福庄流域水源涵养林的植物多样性分析

元阳梯田已有1 200多年的历史,水源涵养林的存在对于梯田的延续具有重要的价值。为得到元阳梯田水源涵养林的植物多样性分布特征,对元阳梯田全福庄流域4种主要植被类型水源涵养林下的植物物种数量特征、物种丰富度、多样性、均匀度等多样性规律进行了标准样地调查。结果表明,研究区共有植物155种,隶属66科,其中,山茶科、禾本科、蓼科植物占有绝对优势,不同植被类型森林群落的优势种不同;物种丰富度大小为:次生常绿阔叶林>杂木林>次生落叶阔叶林>人工水冬瓜林;物种多样性特征表现为,乔木层:次生常绿阔叶林>次生落叶阔叶林>杂木林>人工水冬瓜林;灌木层:次生常绿阔叶林>杂木林>次生落叶阔叶林,人工水冬瓜林无灌木层分布;草本层:次生落叶阔叶林>人工水冬瓜林>次生常绿阔叶林>杂木林。植被分布的物种丰富度和均匀度对物种多样性存在交叉影响。     

林隙与凋落物对天然红松混交林土壤水溶性有机碳的影响

在天然红松混交林3种不同林型(椴树红松混交林(TP)、云冷杉红松混交林(PAP)、枫桦红松混交林(BP))内,各选取小、中、大3个代表性的林隙,将其作为试验样地,并分别以各自的郁闭林分作为对照。2012年6月,在TP林隙及郁闭林分内不同位置的土壤表层埋设3种不同树种的凋落物(红松、椴树、枫桦)分解袋。2012年6-9月测定各林型不同大小林隙及其郁闭林分0-10cm的土壤水溶性有机碳(WSOC)含量。结果表明:TP和BP林隙内及其对照的WSOC均表现为小林隙大林隙中林隙,而PAP表现为大林隙中林隙小林隙;TP和PAP林隙内WSOC郁闭林分,BP则相反;除7月3种林型林隙大小对土壤WSOC影响均不显著(P0.05)外,其他月份林隙大小的影响并不完全一致。PAP和BP林隙内土壤WSOC随月份的变化均为不对称的"V字型"曲线,6月达到峰值,前者7月而后者8月达到谷值。然而,TP林隙内土壤WSOC在生长季内呈持续上升的趋势,9月达到最高值;TP林隙内枫桦凋落物分解袋下的土壤WSOC明显高于红松和椴树凋落物分解袋下的。3种凋落物下土壤WSOC在林隙北部均为小林隙和中林隙的郁闭林分林隙内,而大林隙则相反;TP和PAP林隙内及其对应的郁闭林分土壤WSOC和土壤含水量均为正相关,然而BP为负相关。     

择伐作业对常绿阔叶林乔木层树种结构及物种多样性的影响

研究4种不同强度择伐作业(弱度13.0%、中度29.1%、强度45.8%和极强度67.1%)对常绿阔叶林林分结构及乔木层物种多样性的影响结果表明,轻度与中度择伐对林分结构的影响较小,原林分乔木层优势树种的地位仍保持甚至略有提高;而强度择伐和极强度择伐则引起林分结构一定的变化,一些优势树种的地位削弱,而另一些树种的优势地位上升。但采伐作业不利于常绿阔叶林物种多样性的发展,尤其是林冠强度破坏对物种多样性的影响最大,而轻度与中度择伐作业有利于原有物种保持与恢复,这可能与不同强度择伐作业引起林地光照条件、温度和湿度等环境因子的不同变化有关。     

浙江省典型森林类型枯落物及林下土壤水文特性

选择浙江省5种典型林型(杉木林、毛竹林、阔叶林、针阔混交林、马尾松林)枯落物及林下土壤作为研究对象,布设30m×30m标准样地,枯落物水文效应测定采用浸泡法,土壤层水文效应测定采用环刀法。结果表明:不同林分类型枯落物蓄积量大小介于10.14～25.07t/hm2,排列顺序分别为针阔混交林>阔叶林>马尾松林>杉木林>毛竹林;最大持水量大小介于21.82～33.64t/hm2,排列顺序为针阔混交林>阔叶林>杉木林>马尾松林>毛竹林;有效拦蓄量大小介于16.8～24.84t/hm2,其排序为针阔混交林>杉木林>阔叶林>马尾松林>毛竹林;5种森林类型枯落物的持水量均随浸水时间而增大并逐步趋于稳定,其关系符合对数函数;前0.5h内枯落物吸水速率最大,1h之后吸水速率急剧降低,而后随着时间的推移,枯落物的吸水速率趋于统一,其关系呈幂函数关系;5种森林类型林下土壤容重、非毛管孔隙度、孔隙度、持水能力等指标差异并不显著,土壤持水力均值介于201.86～296.63t/hm2。综合来看,阔叶林及含有阔叶树种的林分持水能力相对高于针叶林。     

天童山常绿阔叶林不同演替阶段水源涵养功能评价

以位于浙江省东部天童国家森林公园内的常绿阔叶林为研究对象,从林冠层、林下枯落物层和土壤层3个生态作用层入手,采用层次分析法综合评价了天童山常绿阔叶林3个不同演替阶段(常绿阔叶林灌丛、木荷林、栲树林)的水源涵养功能,并进行了排序。结果表明,该区水源涵养功能随演替进程逐渐增加,处于演替初级阶段的常绿阔叶林灌丛水源涵养功能最低(0.200 9),演替中后期阶段的木荷林居中(0.363 2),演替顶极阶段的栲树林最强(0.436 0)。     

次生阔叶林定向培育试验及效益研究

 常绿阔叶林是福建省的地带性植被,但在发展食用菌产业中,大量常绿阔叶林被破坏,形成了许多残次林。探索天然残次阔叶林改造成食用菌专用林的技术措施 ,对解决菌林矛盾和水土流失问题有重要意义。对次生阔叶林进行人工促进天然更新,定向培育食用菌专用林改造试验的结果表明:次生阔叶林改造投资省、成林早、生产周期短、经济效益好,第8年蓄积量可达92.1m3/hm2,可提供78.3t/hm2的食用菌原料,投入产出比为1∶139;同时,人工改造措施对群落的物种组成,没有不良影响,具有很好的水土保持和培肥地力功能等生态效益。因此,采取封禁,择优选留目的树种幼苗、幼树,清除杂草、藤蔓和非目的树种,伐去过高的伐桩,选留健壮的萌条,在林中空地进行补植等技术措施,是把天然残次阔叶林定向培育成食用菌原料专用林的有效技术手段。     

江西大岗山3种林型土壤水分物理性质研究

对江西大岗山林区常绿阔叶林、杉木人工林和毛竹林土壤的容重、孔隙度、持水量和贮水量等物理性质进行了研究。结果表明：（1）常绿阔叶林、毛竹林和杉木人工林的土壤容重均随深度的增加而增加。在0～80cm的土层中,杉木人工林、常绿阔叶林和毛竹林的土壤容重分别为1．29g／cm^3,1．24g／cm^3和1．20g／cm^3。（2）随土层深度的增加,3种林型土壤的总孔隙度、毛管孔隙度、饱和持水量和毛管持水量均逐渐降低。（3）在0～80cm的土层中,常绿阔叶林的土壤总孔隙度和非毛管孔隙度最大,毛竹林次之;而常绿阔叶林土壤的毛管孔隙度最小,毛竹林最大。（4）在0～80cm的土层中,3种林型土壤的饱和持水量、毛管持水量和非毛管持水量均为毛竹林〉常绿阔叶林〉杉木人工林。在0～80cm的土层中,3种林型土壤的现有贮水量和饱和贮水量均为常绿阔叶林〉杉木人工林〉毛竹林。（5）毛竹林在0～40cm土层中,土壤物理性质明显优于另外两种林分。     

低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响

【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。     

Pasture Vegetation Elemental Analysis by Laser-Induced Breakdown Spectroscopy

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.     

Assessing the effectiveness of conservation measures: Resolving the “wicked” problem of the Steller sea lion

“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.     

Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage

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.     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

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,     

Macroinvertebrates in North American tallgrass prairie soils: effects of fire, mowing, and fertilization on density and biomass

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.     

Enhanced establishment and growth of giant cardon cactus in an eroded field in the Sonoran Desert using native legume trees as nurse plants aided by plant growth-promoting microorganisms and compost

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.     

Variation in quality parameters between and within 14 Nordic tree fruit and berry species

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.     

Karyotypic and genome size variation in Cajanus cajan (L.) Millsp. (pigeonpea) and some wild relatives

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.     

Effect of some fungicide seed treatments on the survival of Bradyrhizobium japonicum and on the nodulation and yield of soybean [Glycine max. (L) Merr.]

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.