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1.
The present taxonomic revision deals with Neotropical species of three entomopathogenic genera that were once included in Hypocrella s. l.: Hypocrella s. str. (anamorph Aschersonia), Moelleriella (anamorph aschersonia-like), and Samuelsia gen. nov (anamorph aschersonia-like). Species of Hypocrella, Moelleriella, and Samuelsia are pathogens of scale insects (Coccidae and Lecaniidae, Homoptera) and whiteflies (Aleyrodidae, Homoptera) and are common in tropical regions. Phylogenetic analyses of DNA sequences from nuclear ribosomal large subunit (28S), translation elongation factor 1-α (TEF 1-α), and RNA polymerase II subunit 1 (RPB1) and analyses of multiple morphological characters demonstrate that the three segregated genera can be distinguished by the disarticulation of the ascospores and shape and size of conidia. Moelleriella has filiform multi-septate ascospores that disarticulate at the septa within the ascus and aschersonia-like anamorphs with fusoid conidia. Hypocrella s. str. has filiform to long-fusiform ascospores that do not disarticulate and Aschersonia s. str. anamorphs with fusoid conidia. The new genus proposed here, Samuelsia, has filiform to long-fusiform ascospores that do not disarticulate and aschersonia-like anamorphs with small allantoid conidia. In addition, the present study presents and discusses the evolution of species, morphology, and ecology in Hypocrella, Moelleriella, and Samuelsia based on multigene phylogenetic analyses.Taxonomic novelties: New genus: Samuelsia. New species: Hypocrella disciformis, H. hirsuta, Moelleriella basicystis, M. boliviensis, M. cornuta, M. evansii, M. madidiensis, M. umbospora, S. chalalensis, S. geonomis, S. intermedia, S. rufobrunnea, and S. sheikhii. New combinations: M. castanea, M. colliculosa, M. disjuncta, M. epiphylla, M. gaertneriana, M. globosa, M. guaranitica, M. javanica, M. libera, M. macrostroma, M. ochracea, M. palmae, M. phyllogena, M. rhombispora, M. sloaneae, M. turbinata, and M. zhongdongii.  相似文献   

2.
Abstract Dry artificial diet pellets prepared with maize, cassava chips, and amino acid supplements (lysine and methionine) were evaluated for mass culture of Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), a highly polyphagous pest of many stored grains. Evaluation was done in the laboratory at temperature 26 ± 2 °C, 60-70% RH, 12:12 L:D photoperiod. The artificial diet was compounded from different proportions of maize (M) variety TZPB-SW-R, cassava (C) variety TMS-2110, and amino acid supplements, and was pelletized into 6 mm diameter pellets on which five pairs of one-day-old S. zeamais were bioassayed. The diet M(9)C(1) (90% M and 10% C) was the most suitable diet with comparatively shorter developmental period (34.8 days) and the highest F(1) emergence of progeny (145.4) compared to the control, M(10)C(0) (100% M and 0% C).  相似文献   

3.
BOOK REVIEWS     
Book reviews in this article:
PANOS, D. A., SOTIRIADIS, S. and FIKAS, E. Grassland's progress in Greece
COOPER, M. M c G. Grass Farming .  相似文献   

4.
BOOK REVIEWS     
《Grass and Forage Science》1967,22(4):298-298
Book reviewed in this article:
WHYTE, R. O. Milk production in developing countries.
RICOU, G. [Study of biocoenosis of a "natural" environment: the grazed permanent grassland.]
KIRCHGESSNER, M.; FRIESECKE, H. and KOCH, G. Nutrition and the composition of milk.
NORTH, P. M. Poisonous plants and fungi in colour.  相似文献   

5.
Megacopta cribraria (Hemiptera: Plataspidae) continually outbreaks due to suitable photoperiod in recent years. Effect of photoperiod on growth, development and reproduction of M. cribraria were assessed in this study. Results indicated that developmental duration, nutrient accumulation efficiency, and adult fecundity of M. cribraria were significantly different under 6 photoperiodical conditions. Developmental duration of nymph stage gradually tended to be shorter as day time increase. Body weights of 5th instar nymphs for 16 h and 4 h day time photoperiods were 5.2 mg and 4.6 mg, respectively. Moreover, longevity of adults tended to be longer as day time increase. However, for the short day photoperiod (4 L:20 D and 8 L:16 D), population showed no reproductive behaviors. Index of population trend increased with photoperiod extension and adults showed stronger reproductive capacity and longer longevity. This research identified the favorable photoperiodical conditions before outbreak. It may provided reference for ecological adaptability of M. cribraria, and contribute to the scientific basis for forecasting and controlling of M. cribraria.  相似文献   

6.
以彩色马蹄莲栽培品种‘M7507’、‘M2’、‘M37’的幼胚为实验材料, 采用L9(34)的正交实验设计, 对其离体胚培养, 即胚拯救的适宜发育阶段和适宜培养基进行研究。 结果表明: (1)幼胚发育阶段显著影响彩色马蹄莲胚拯救成功率, 最佳发育阶段幼胚的形态特征为球状、 乳白色、光滑; (2)适宜诱导培养基为MS+6-BA 1.0 mg/L+NAA 0~0.2 mg/L; (3)幼胚接种后不同品种初始萌发所需时间不同,‘M2’、 ‘M7507’、 ‘M37’依次为14、 16、 21 d, 品种间萌发率经新复极差法检验差异不显著; (4)不同品种的果实膨大速度不同,发育到胚拯救的最适阶段, ‘M7507’、 ‘M2’、 ‘M37’分别需要50、 60、 65 d左右的时间。  相似文献   

7.
The objectives of this research were: 1) to try to determine the inheritance of the resistance toMeloidogyne incognita, M. javanica, andM. arenaria and 2) to study genetic relationships among the three species of root-knot nematodes in potatoes. The source of resistance used wasSolanum sparsipilum. The progenies analyzed in this study may be grouped into a few discrete segregation patterns, three forM. incognita andM. javanica and two forM. arenaria. More than one dominant locus, but not many loci are needed to explain the segregation obtained in the three species. Susceptible clones ofS. sparsipilum possess recessive or epistatic genes which affect the pattern of segregation for resistance, when these clones are crossed to resistant clones. Maternal effects were expressed in reciprocal crosses between susceptible and resistant clones when they were tested for resistance toM. arenaria. Clones in this study which are resistant toM. arenaria are also resistant toM. incognita andM. javanica  相似文献   

8.
采用人工接种的方法,研究了普通油茶、博白大果油茶、广宁红花油茶、香花油茶和陆川油茶对南方根结线虫的抗性。结果表明:普通油茶易感南方根结线虫,广宁红花油茶、香花油茶和陆川油茶中抗南方根结线虫,博白大果油茶高抗南方根结线虫;接种60 d内调查,南方根结线虫侵入博白大果油茶后不能完成其生活史,而普通油茶在28 d内就能完成生活史并繁育后代;接种根结线虫后对博白大果油茶、广宁红花油茶、香花油茶和陆川油茶的生长没有显著性影响,但抑制普通油茶茎、叶的生长的同时促进其侧根的生长。  相似文献   

9.
Genetic variation, including agronomic trait variation, often occurs in somatic cell culturing. In this study, we compared the main agronomic traits of two rice mutants, M3 and M14, which were derived from Shenxiangjing 5 somatic cell culturing. Significant differences were found between the two mutants and the wild rice Shenxiangjing 5 (Table 1). Results were as follows:  相似文献   

10.
玉米‖花生间作系统作物产量及根系空间分布特征的影响   总被引:5,自引:1,他引:4  
在农业部阜新农业环境与保育科学观测试验站分别设置2行玉米:4行花生间作(2M4P)、4行玉米:4行花生间作(4M4P)和玉米单作、花生单作4个种植模式,开展不同种植模式对作物产量及产量构成因素、生物量和根系特征的影响研究。结果表明,2个间作模式的土地当量比(LER)为1.16~1.24,具有一定的产量优势和较高的土地利用效率。间作中的玉米干物质积累量与单作接近,间作花生干物质积累量较单作明显下降。对根系研究发现,间作减少作物的细根生长,2M4P、4M4P处理的比根长(SRL)较单作玉米和花生分别下降了25%、23%和18%、12%,复合系统作物根表面积密度(RSAD)在0~40 cm土层中能够占到总土层的80%以上,间作作物的RSAD显著高于单作,表明作物根系在表层分布较为密集,间作影响了作物的根系生长与分布。  相似文献   

11.
Background: Asthma is a chronic inflammatory disorder of the airways. The available treatment options have major limitations owing to low efficacy, associated adverse events and compliance issues. Therefore, the health burden of bronchial asthma is increasing globally at an alarming rate, providing a strong impetus for the development of new therapeutics. Myrica sapida is known traditionally in Ayurveda to possess anti-asthmatic activity. Hence, the present investigation was undertaken to evaluate the bronchodilator and anti-anaphylactic activity of the stem bark of Myrica sapida. Methods: Experimental models studied were acetylcholine induced bronchospasm in guinea pigs, egg albumin induced anaphylaxis in guinea pigs, in vitro studies on tracheal strip of egg albumin sensitized guinea pigs. Results: Treatment with ethanolic extract of M. sapida, 75 mg/kg, orally resulted in significant protection against acetylcholine aerosol induced bronchospasm and allergen induced anaphylaxis in guinea pigs. Ethanolic extract of M. sapida (75 mg/kg, p.o.) prevented the potentiation of responses and also produced a decrease in pD2 value of histamine and acetylcholine in guinea pig tracheal strip. Conclusion: These results suggest that M. sapida possesses bronchodilator activity, has potent inhibitory effect on immediate hyper-sensitivity reactions and decreases bronchial hyper-responsiveness.  相似文献   

12.
【目的】探明秸秆还田和氮肥管理对麦/油后直播杂交稻氮素积累、转运、氮肥利用效率及籽粒产量的影响。【方法】选用优质三系杂交稻宜香优2115,采用二因素裂区设计,麦、油茬田同步开展试验,处理完全一致。主区为麦/油秸秆全量翻埋还田(M1)和秸秆不还田(对照,M0),副区设4个氮肥管理,即不施氮对照(N0)、m基肥∶m分蘖肥∶m促花肥∶m保花肥比例分别为1∶0∶0∶0(N1)、3∶3∶2∶2(N2)、2∶2∶3∶3(N3),测定了直播杂交稻主要生育时期各器官的氮素积累量及籽粒产量。【结果】结果表明,两种轮作方式下,氮肥管理对直播杂交稻主要生育时期的氮素积累、齐穗后茎鞘、叶片的氮素转运及稻株氮素利用效率均存在显著或极显著的调控效应。秸秆还田显著提高麦/油茬杂交稻中后期的氮素积累量、茎鞘和叶片的氮素转运量以及氮肥利用效率,其中,氮肥农学利用率、氮肥偏生产力和氮肥表观利用率较秸秆不还田分别提高了34.96%/28.76%、2.52%/2.61%和31.91%/22.30%。同时,油菜秸秆还田下直播杂交稻各生育时期氮素积累和产量较麦秆还田表现更好,籽粒产量提高481 kg/hm2(5.22%)。M1N2处理、M0N3处理下,直播杂交稻各阶段的氮素积累速率明显加大,促进结实期茎鞘和叶片的氮素向穗部转运,成熟期稻株氮素积累量优势明显且有较高的氮素利用效率(麦/油茬稻氮肥农学利用率、偏生产力和表观利用率分别达17.87 kg?kg–1/17.85 kg?kg–1、67.27 kg?kg–1/71.28 kg?kg–1、74.93%/75.05%),最终实现高产。【结论】在麦/油-稻轮作下秸秆全量还田,配合N2氮肥管理,可有效提高直播杂交稻氮素吸收、利用效率,增加籽粒产量,尤以油菜秸杆还田的效果更好。  相似文献   

13.
为了解不同季秸秆还田对小麦产量形成和氮素利用的效果,以安徽淮北平原砂姜黑土麦区主栽小麦品种烟农19为供试材料,设置W0M0(小麦、玉米双季秸秆均不还田)、W0M1(小麦秸秆不还田,玉米秸秆还田)、W1M1(小麦、玉米双季秸秆还田)和W1M0(小麦秸秆还田,玉米秸秆不还田)4个处理,比较分析了不同季秸秆还田对冬小麦干物质积累分配及氮素利用率的影响。结果表明:(1)与W0M0处理相比,秸秆还田处理(W0M1、W1M1和W1M0)的冬小麦开花期和成熟期干物质积累量分别增加了7.9%~25.4%和17.0%~33.3%,花前干物质转运效率提高了4.5~9.7个百分点,花前干物质对籽粒产量贡献率增加了10.8~18.5个百分点;(2)秸秆还田处理可增加冬小麦产量4.3%~12.7%,且W1M0处理增产效果最显著;(3)W0M1和W1M0处理均能提高冬小麦氮素利用效率和氮肥生产效率。总体而言,单季小麦秸秆还田有利于实现淮北平原砂姜黑土区冬小麦高产与氮高效。  相似文献   

14.
Lyngbyabellin M is a non-ribosomal peptide synthetase/polyketide synthase derived metabolite isolated from the cyanobacterium M. bouillonii displaying thiazole rings and a distinct chlorinated octanoic acid chain. Its absolute configuration was proposed based on the comparison of its spectroscopic data with those of other representatives of this family of marine natural products, as well as degradation and derivatization studies. Here the first total synthesis of (+)-lyngbyabellin M is described based on the coupling of three key intermediates: two chiral thiazole moieties and an anti hydroxycarboxylic acid prepared stereoselectively via a boron enolate mediated aldol reaction directed by Masamune’s chiral auxiliary.  相似文献   

15.
Genetic gains of cultivated peanut (Arachis hypogaea L.) have increased harvest index and disease tolerance, resulting in improved yield potential and broad-range adaptability of peanut cultivars to United States (U.S.) peanut production regions. Although this strategy has been successful, future yield increases may require peanut cultivars specifically adapted to environmental and management systems of a particular production region. Irrigation is one major management factor that varies across U.S. production regions and influences yield stability. Therefore, peanut germplasm selection for developing specifically adapted cultivars depends on knowledge of genotypic (G) pod yield responses to irrigation (M) across contrasting environmental (E) conditions (G × E × M interaction). The objectives of this 2-year study were to characterize germplasm by: (i) examining genotypic pod yield response to irrigation at locations in Florida and Texas; and (ii) estimating the genotypic pod yield performance and stability using genotype plus genotype-by-environment interaction (GGE) biplots. At the Florida location, genotypes New Mexico Valencia C (NMVC), COC 041, and Chico responded positively to increasing water application, whereas FloRun? ‘107?, C76 16, and FlavorRunner 458 responded negatively. Genotypes C76 16, ICGS 76, Chico, and ICGV 86015 had pod yields greater than the population mean. The genotype ICGS 76 had both high pod yields and stability. Pod yields of Chico were greater at the southwest locations, whereas ICGV 86015 had greater pod yields at the southeast locations. These results demonstrate a range in adaptability of distinct peanut genotypes that can be used in breeding programs for developing improved cultivars.

Abbreviations: G × E: genotype-by-environment interaction; G × E × M: genotype-by-environment-by-management interaction; G × M: genotype-by-management interaction; NMVC: New Mexico Valencia C; TWRPET: total water received as a percentage of ETo  相似文献   

16.
BOOK REVIEWS     
《Grass and Forage Science》1970,25(2):191-192
Book reviewed in this article:
GOULD, F. W. Grass systematics .
RORISON, I. H. [Ed.] Ecological aspects of the mineral nutrition of plants. A symposium of the British Ecological Society, Sheffield, 1–5 April 1968 .
HAGAN, R. M.; HAISE, H. R.; EDMINSTER, T. W. [Eds] Irrigation of agricultural lands .
RICHARDSON, M. Translocation in plants .  相似文献   

17.
BOOK REVIEWS     
《Grass and Forage Science》1962,17(2):159-159
Book reviews in this article:
M c M eekan , C. P. Grass to milk .
MURDOCH, J. C. Making and feeding silage .  相似文献   

18.
Formulations using cassava starch or inulin plus milk were fermented with three different lactic acid bacteria (LAB) strains: Lactobacillus plantarum D34, Lactobacillus sp. SLH6, and Streptococcus thermophilus ST4. Growth and acidification were followed in 3% powdered milk (M3), 3% milk–6% starch (M3-S6), and 3% milk–6% inulin (M3-In6). D34 and SLH6 growth was enhanced by starch in M3-S6, when compared to the count (CFU/ml) obtained in M3. Growth of all strains was promoted by inulin. All fermented products showed LAB counts of 8.0 log or higher. Carbohydrate utilization was in agreement with growth and acidification results. The highest increase in CFU in rat feces was observed in M3-S6 fermented with ST4; the D34 fermented product also increased CFU but SLH6 did not, either with starch or inulin. This suggests that ST4 and D34 strains provide a good choice to ferment the proposed formulations in order to obtain a marked improvement of natural intestinal flora.  相似文献   

19.
氮肥运筹模式对冬小麦氮素吸收利用的影响   总被引:9,自引:0,他引:9  
为给小麦高产、高效、无污染及可持续生产提供合理的氮肥运筹技术和理论依据, 以烟农19为材料,在大田条件下,研究了不同施氮量和基追比例对土壤小麦系统氮素积累及分配的影响。结果表明,施氮可提高0~100 cm土体内的全氮含量。在小麦越冬前, 0~40 cm土层中NO3-N含量随氮肥用量和基肥比例的增加显著增加;起身期到拔节期,施氮量为180和240 kg·hm-2且基肥∶拔节肥∶孕穗肥为3∶5∶2处理的0~40 cm土层内NO3-N含量下降,而施氮量为240 kg·hm-2且基肥∶拔节肥为7∶3和5∶5的处理及施氮量为300 kg·hm-2且基肥∶拔节肥为7∶3的处理则显著增加;拔节期到成熟期,随施氮量的增加,0~60 cm土层速效氮增加幅度有所提高。孕穗肥可明显提高灌浆期的植株全氮含量。因此,在240 kg·hm-2 施氮水平、基肥∶拔节肥∶孕穗肥为3∶5∶2条件下,施氮既能减少土壤硝态氮累积量,又能有效降低土壤硝态氮污染地下水的可能性。  相似文献   

20.
BOOK REVIEWS     
《Grass and Forage Science》1961,16(2):174-176
Book reviews in this article:
WATSON, S. J. and NASH, M. J. The conservation of grass and forage crops .
BOR, N. L. The grasses of Burma, Ceylon, India and Pakistan (excluding Banibuseae) .
DAVIES, W. The grass crop, its development, use and maintenance .
ELWELL, F. R. Science and the farmer .
EDDOWES, M. and HARRIS, R. Measuring output from grassland in terms of amimal production .  相似文献   

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