抗枣疯病种质资源的筛选与应用

枣疯病是一种毁灭性的植原体病害。在全国范围内收集待鉴定抗枣疯病种质29份,采用在重病大树上高接待鉴定种质的高强度筛选方法,经过8年多的筛选和验证,从中筛选出4份抗性强且稳定的高抗单系,即骏枣单系、南京木枣单系、称砣枣单系、清徐圆枣单系。将骏枣高抗单系用于高接改造病树,已连续5年正常生长结果,未再次感染枣疯病。这些抗病单系既可直接作为抗病品种进行栽培,也可用于染病植株和感病品种的高接改造。     

玉米种质和新品种对腐霉茎腐病和镰孢穗腐病的抗性分析

玉米是我国最重要的农作物之一,腐霉茎腐病和镰孢穗腐病是玉米生产上的重要病害。2006-2012年期间,对1647份玉米种质进行了抗肿囊腐霉茎腐病和拟轮枝镰孢穗腐病鉴定,筛选出高抗茎腐病和穗腐病的种质分别为564份和27份,占鉴定总材料的34.2%和1.6%,抗性材料分别为209份和352份,占比为12.7%和21.4%,表明高抗肿囊腐霉茎腐病的资源较为丰富,高抗镰孢穗腐病的种质相对匮乏。其中,13份种质对2种病害均表现高抗,207份种质对2种病害均表现抗性或对其中一种表现高抗而另一种表现抗性。自交系中对肿囊腐霉茎腐病和拟轮枝镰孢穗腐病表现抗性以上(含HR和R)的种质分别占总鉴定种质的56.5%和23.6%,在农家种中分别为21.2%和21.4%,表明玉米自交系中的抗性资源较农家种丰富。2009-2013年期间参加国家玉米区试的品种中,对腐霉茎腐病表现高抗、抗性、中抗、感病和高感的品种分别占11.5%、11.9%、40.1%、17.6%和18.9%。2009-2011年间,中抗以上的育成品种所占比例呈现明显上升趋势,但2012-2013年间,中抗以上的品种所占比例呈下降趋势。     

花生种质资源果腐病的抗性评价

花生果腐病是一种由真菌引起的世界性的严重病害,直接影响花生的产量及品质。通过田间自然发病对引进的77份美国资源和39份国内资源进行连续2年的鉴定,筛选抗果腐病的花生种质资源,为花生抗果腐病育种提供优异材料。结果表明:供试花生材料间的受害指数差异极显著(P0.01),两年间的差异也达到显著水平(P0.05)。根据受害指数的聚类分析将供试花生材料的果腐病抗性分为高抗、抗、中抗、感病和高感病5组,该结果作为花生果腐病抗性评价标准,能够明确评价供试花生材料对果腐病的抗性。综合两年抗性表现较一致的96份种质,筛选到高抗材料2份,平均受害指数分别为16.67和21.91;抗性材料6份,平均受害指数分布在26.33~42.41之间;中抗材料32份,平均受害指数在45.19~60之间;感病材料34份,平均受害指数在60.87~74.39之间;高感材料22份,平均受害指数在75.27~83.34之间。该结果为评价花生果腐病抗性和合理利用种质资源进行花生抗病品种遗传改良提供了参考和优异材料。     

抗青枯病烟草种质资源在云南省的评价

筛选出抗性稳定的种质资源是选育抗病品种的重要基础。本文采用人工接种和病田自然发病方法鉴定了48份烟草种质的青枯病抗性表现。土壤盆栽接种鉴定表现为高抗的材料有CF207、岩烟97、TI448A、DB101、G80、RG17、GTH-1等7份材料,表现抗病的有MSK149、Oxford 2028、NC95、YN108、K346、K358、Enshu FC、Oxford 207、RG11等9份材料。苗期恒温水培接种鉴定结果表明,Oxford 207和岩烟97表现为高抗,Enshu FC表现抗病,抗病材料与云烟85和K326杂交F1的抗性表现为中感至抗病。田间自然发病鉴定结果表明,我国审定的中抗青枯病的品种RG17、RG11、K358和K346,在云南省田间抗性表现为中抗,产值较高。TI448A田间表现为抗青枯病,但易感黑胫病和空茎病。Oxford 2028和Oxford 207田间表现为抗病至高抗,产值较高。G3和岩烟97田间分别表现为高抗和抗病,产值较低。根据接种鉴定和田间病圃2年抗性鉴定,筛选出育种潜力较大的青枯病抗源Oxford 207、Enshu FC,岩烟97和TI448A。     

小麦种质对茎基腐病抗性评价及优异种质筛选

小麦茎基腐病是由镰孢菌侵染引起的一种世界性土传病害,近年来已严重威胁到我国小麦的安全生产。为筛选具有茎基腐病抗性的小麦种质资源,本研究采用孢子悬浮液浸种法,分别以国外抗病材料Sunco和中国品种陕253为抗病和感病对照,对670份我国小麦品种(系)进行了茎基腐病温室苗期抗性鉴定。结果发现,我国供试品种(系)感病材料(病情指数>30)所占比例达到84%,且包含多个近年来小麦生产中的主推品种,表明我国小麦品种总体抗性水平低是导致茎基腐病近年来发病频率与程度不断增加的重要原因之一。经多轮筛选,发掘获得15份抗病表现稳定、抗性水平与抗病对照Sunco相仿的材料。15份材料平均病情指数在10.9~19.4之间,其株高、抽穗期等农艺性状表现出较为丰富的变异,为我国小麦抗茎基腐病品种选育和抗性遗传研究提供了种质资源。     

玉米粗缩病改良新抗源T877的抗性评价

玉米粗缩病是我国玉米产区的一种重要病害。本研究利用自然接虫法初步鉴定了41份玉米自交系对粗缩病的抗性,并对其中有代表性的10份材料进行了3个播期的试验。筛选出3份高抗、4份抗、3份中抗材料,大部分材料(占75.6%)表现为感和高感,抗性较好的材料属于PB亚群。高抗粗缩病自交系T877在不同年份、不同播期间抗性稳定,以此为亲本育成苏玉19等新品种。     

我国蚕豆品种资源对细菌性茎疫病的抗性鉴定

1998～1999年对156份蚕豆品种(系)进行抗蚕豆细菌性茎疫病鉴定,其中表现免疫的材料有11个,占7．05%,高抗和抗病的品种108个,占69．22%,感病和高感品种37个,占23．72％。结果表明,不同地理来源的品种,不同株高及粒重的材料抗性有差异。     

玉米种质资源对六种重要病虫害的抗性鉴定与评价

在2003-2005年间,对604份玉米种质进行了抗弯孢菌叶斑病和玉米螟鉴定,筛选出抗弯孢菌叶斑病的材料93份,抗玉米螟材料22份。2006-2009年间,对836份玉米种质进行了抗大斑病、茎腐病、穗腐病和瘤黑粉病的鉴定与评价,筛选出一批高抗和多抗的资源。在836份资源中,对大斑病1、2和N号3个生理小种具有抗性的材料均为50%左右;抗茎腐病材料为41.3%,高抗和抗性种质分别为264和81份;穗腐病高抗和抗性种质分别为5和171份,占比为21.1%;瘤黑粉病高抗和抗性种质各261和14份,占总鉴定材料的32.9%。上述结果表明抗大斑病、茎腐病和瘤黑粉病的种质资源较为丰富。通过对抗性结果进行对比分析,发现不同生态区玉米种质的抗性强弱以及抗性多样性存在明显差异,黑龙江和内蒙古的种质对病虫害的抗性强弱及多样性程度明显高于四川种质。此外,玉米自交系对病虫害的抗性强弱以及多抗性程度高于农家种。     

药用野生稻体细胞杂交后代对条纹叶枯病的抗性鉴定

目的：从药用野生稻体细胞杂交后代中筛选对水稻条纹叶枯病具有抗性的水稻种质。方法：利用苗期接种法对药用野生稻体细胞杂交后代进行表型抗性评价,利用ELISA技术对供试材料进行感病率检测。结果：34份F1个体中,Y37、Y39、Y42和Y45的抗病级别都为高抗,它们的感病率分别为5.7%、5.7%、5.7%和4.3%,表现高抗水稻条纹叶枯病。结论：筛选到4个高抗条纹叶枯病水稻材料。     

大麦种质资源白粉病抗性鉴定与应用

为了充分利用抗病大麦种质资源,对本所多年来征集的921份国内外大麦品种资源进行白粉病田间自然鉴定.结果表明,田间表现高抗品种有181个,占总数19.65%,抗病品种163个,占总数17.70%;表现感病品种有447个,占总数的48.53%,高感品种130个,占总数14.12%.通过品种的全生育期、株高、穗长、穗实粒数、结实率、穗粒重和千粒重等7个主要农艺性状的分析表明,181个高抗种质主要农艺性状均存在较大的遗传分化.本文还对抗病种质木石港3号、植3和S-096等在育种中的应用进行了阐述.     

枣树访花昆虫多样性及药剂的影响

为了解枣树花期的访花昆虫,更好地利用昆虫为其授粉,本文对山西运城市临猗县、晋中市太谷县和吕梁市临县3地枣树的访花昆虫进行了调查,结果表明:枣树访花昆虫共计23种,隶属4目12科。运城临猗与晋中太谷间群落相似性最高,相似性系数为0.27,属于中等不相似,其它为极不相似。日活动规律观察表明,膜翅目与双翅目都属于单峰型,活动高峰为9∶30-10∶00、7∶30-8∶00。同一生境下,喷施药剂会影响访花昆虫的数量,一天中喷施清水的枣树访花昆虫244头,喷施药剂的枣树访花昆虫仅61头。     

新疆野苹果果实形态与矿质元素含量多样性以及特异性状单株

对新疆野苹果伊犁霍城县大西沟、巩留县莫合乡库尔德宁和新源县交吾托海等3个种下居群果实形态多样性及生存现状进行了调查研究并结合香味物质、矿质元素含量等测定结果筛选出4株特异性状单株,旨在为探讨栽培苹果的起源演化提供基本资料,并为新疆野苹果保护利用提供科学依据。结果表明,①新疆野苹果的果实形状、大小、颜色和果柄长度等形态性状的变异系数均在10％以上,表现出较丰富的遗传多样性,3个居群的变异趋势基本一致。尤其是本文首次对巩留县莫合乡库尔德宁居群果实形态性状进行调查研究,其中单果重的变异幅度为9．95～47．47g,变异系数29．71％,形状有扁圆形、近圆形、圆形和圆锥形等,果皮颜色有绿、黄、橘黄、粉红、红和深红等,具有栽培苹果的典型特征。上述结果支持“新疆野苹果可能是栽培苹果祖先种”的结论;②对巩留县莫舍乡的新疆野苹果78个实生株系果肉组织Ca、Mg、Fe、Zn、Cu、Mn6种矿质营养元素进行测定的结果表明,每种矿质元素含量单株间差异显著,变异系数在24．2％～54．0％,遗传多样性丰富,进一步选择的潜力很大;③根据新疆野苹果果实形态、香味物质和矿质元素含量等的测定结果,初步筛选出了大果型、高钙型、高锌型和大马酮型等4个特异性状单株;④调查发现,由于农田开垦、过度放牧以及苹果小吉丁虫的蔓延危害,目前伊犁野果林面积逐年减少,野苹果固有的繁育体系和遗传多样性受到不同程度的破坏。为此,本文提出了建立新疆野苹果原生境保存、异地保存、离体保存和利用保存等多层次保护保存体系的建议。     

Frugivory and seed dispersal by chelonians: a review and synthesis

In recent years, it has become clear that frugivory and seed dispersal (FSD) by turtles and tortoises is much more common than previously thought. We here review published and unpublished records of chelonian FSD, and assess the role of chelonians as seed dispersers, from individual species to the community level. We first discuss the distribution of chelonian FSD and the characteristics of the fruit and/or seed species eaten and dispersed by chelonians. We then use the seed dispersal efficiency framework to explore the quantitative and qualitative components of seed dispersal by tortoises and turtles, embarking on a journey from when the fruits and/or seeds are consumed, to when and where they are deposited, and assess how efficient chelonians are as seed dispersers. We finally discuss chelonian FSD in the context of communities and of chelonians as megafauna. A substantial proportion of the world's aquatic and terrestrial turtles and a major part of testudinid tortoises (71 species in 12 families) include fruits and/or seeds in their diet; fruits of at least 588 plant species in 121 families are ingested and/or dispersed by chelonians. For some chelonians, overall or in certain seasons, fruit may even form the largest part of their diet. Contrary to seed dispersal by lizards, the other major reptilian frugivores, chelonian FSD is not an island phenomenon in terms of geographic distribution. Nevertheless, on islands tortoises are often among the largest native terrestrial vertebrates – or were until humans arrived. We synthesise our knowledge of chelonian FSD, and discuss the relevance of our findings for conservation and restoration, especially in relation to rewilding with large and giant tortoises.     

Non-Contrast Enhanced MR Angiography (NCE-MRA) of the Calf: A Direct Comparison between Flow-Sensitive Dephasing (FSD) Prepared Steady-State Free Precession (SSFP) and Quiescent-Interval Single-Shot (QISS) in Patients with Diabetes

Objectives

To compare the image quality and diagnostic performance of two non-contrast enhanced MR angiography (NCE-MRA) techniques using flow-sensitive dephasing (FSD) prepared steady-state free precession (SSFP) and quiescent-interval single-shot (QISS) for the calf arteries in patients with diabetes.

Materials and Methods

Twenty six patients underwent the two NCE-MRA techniques followed by contrast-enhanced MRA (CE-MRA) of lower extremity on a 1.5T MR system. Image quality scores, arterial stenosis scores, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), vessel sharpness, and diagnostic accuracy for detecting more than 50% arterial stenosis were evaluated and statistically compared using CE-MRA as the reference standard.

Results

All examinations were performed successfully. Of the total 153 calf arterial segments obtained in the 26 patients, FSD and QISS showed no significant difference in the number of diagnostic arterial segments (151 [98%] vs. 147 [96%], respectively, P>0.05). The image quality of FSD was higher than that of QISS in the peroneal artery and posterior tibial artery (P<0.05), but no significant difference in the anterior tibial artery (P>0.05). SNR and CNR of FSD were higher than those of QISS (P<0.01), while FSD showed comparable vessel sharpness compared with QISS (P>0.05). The time efficiency of SNR and CNR between FSD and QISS showed no significant difference when taking into account the times for FSD-related scout scans. There was no difference in sensitivity (95% vs. 93%, P>0.05) and negative predictive value (98% vs. 97%, P>0.05) between FSD and QISS for detecting stenosis greater than 50%. However, FSD showed higher specificities (99% vs. 92%, P<0.05) and diagnostic accuracy (98% vs. 92%, P<0.05) compared to QISS.

Conclusion

Both FSD and QISS had similar high sensitivity and negative predictive value for detecting calf arteries with over 50% stenosis, but FSD showed slightly higher diagnostic specificity and better depiction of arterial lesions due to its isotropic submillimeter spatial resolution. QISS, being an easier to use and less time-consuming technique, could be a method of choice for rapid screening of arterial disease of the lower extremity.     

VARIATION IN AVERAGE SEED SIZE AND FRUIT SEEDINESS IN A FRUIT CROP OF A GUANACASTE TREE (LEGUMINOSAE: ENTEROLOBIUM CYCLOCARPUM)

A detailed examination of the ordinary 1980 fruit crop of an ordinary large adult guanacaste tree (Enterolobium cyclocarpum) in Guanacaste Province, Costa Rica (1980) shows that for fruits with about 6-16 seeds (range, 1-18 seeds per fruit) there is about ***1 g dry weight fruit tissue per seed (seeds averaging about 820 m each). Fruits that have about 1-5 seeds on average have 1.5-3 times as much dry fruit tissue per seed as do the seed-rich fruits, and also contain seeds that weigh about 8% more on average than the seeds in the seed-rich fruits. The average seed weight per fruit was found to decrease slightly if all sizes of fruits are considered, but to remain essentially constant over the range of 7-16-seeded fruits. This category contained 78% of the fruits. These findings suggest that different parts of the seed crop may end up in different dispersers and dispersers with different preferences for fruit seediness and tolerances for seed size may remove different portions of the seed crop.     

Female Sexual Dysfunction in Women with Non-Malignant Cervical Diseases: A Study from an Urban Chinese Sample

Non-malignant cervical diseases are common causes of disease among women worldwide. Although many studies have focused on sexual function in women with cervical cancer, little is known about the prevalence of female sexual dysfunction and its risk factors in women with non-malignant cervical diseases. The present study aims to assess sexual function in Chinese women with non-malignant cervical diseases and to identify potential risk factors for these diseases. A cross-sectional hospital-based survey was conducted in Nanjing, China. The Chinese version of the Female Sexual Function Index (CVFSFI) was used to evaluate sexual function. Three hundred three women who had been diagnosed with at least one non-malignant cervical disease and 293 healthy women were recruited from Nanjing Maternity and Child Health Hospital of Nanjing Medical University. We found that women with non-malignant cervical diseases had a significantly higher prevalence of female sexual dysfunction (FSD) (51.8% vs. 34.8%), low desire (43.2% vs. 26.3%), arousal disorder (41.6% vs. 28.3%), and lubrication disorder (51.2% vs. 36.9%) compared with the control group. Cervicitis and cervical intraepithelial neoplasia (CIN) were found to be independent risk factors for FSD. Our study indicates that women with cervicitis and CIN are at a high risk for FSD and deserve focused initial and follow-up management.     

Beneficial effects of natural products on female sexual dysfunction: A systematic review and meta-analysis

BackgroundFemale sexual dysfunction (FSD) includes female orgasmic disorder, female sexual interest or arousal disorder, and genito-pelvic pain or penetration disorder. FSD affects 40% of women worldwide, but it is understudied and likely undertreated. Natural products are frequently used by women to treat FSD, but scientific evidence of their efficacy is lacking.ObjectiveThis systematic review and meta-analysis focused on the study of the efficacy of natural products on FSD.Study designSystematic review and meta-analysis of existing studies on natural products in the treatment of FSD.MethodsThe literature search included MEDLINE, EMBASE, PsycINFO, and the Cochrane Central Register of Controlled Trial databases for studies published from January 2000 to February 2020. The quality and the level of evidence of the studies were assessed. The association between natural products and FSD was summarized using standardized mean differences (SMD) with a 95% confidence interval (CI).ResultsA total of 536 studies were identified, with 20 of them meeting the criteria. According to this meta-analysis, Tribulus terrestris showed a significant positive effect in improving overall female sexual function (SMD = 1.12, 95% CI = 0.46 - 1.79, p = 0.001) and individual sexual arousal (SMD = 1.03, 95% CI = 0.22 - 1.84, p = 0.013), sexual desire (SMD = 1.08, 95% CI = 0.52 - 1.63, p ≤ 0.001) and sexual orgasm (SMD = 0.51, 95% CI = 0.02 - 1.00, p = 0.040) domains compared to placebo. Panax ginseng was found to be effective in treating sexual arousal (SMD = 0.54, 95% CI = 0.11 - 0.97, p = 0.014) and sexual desire (SMD = 0.59, 95% CI = 0.27 - 0.90, p < 0.001) compared to placebo. Meanwhile, other natural products reviewed in this study, such as Trifolium pretense, did not differ significantly from placebo in terms of improving FSD.ConclusionPreliminary evidence suggests that Tribulus terrestris and Panax ginseng may be effective as alternative treatments for FSD in a clinical setting.     

A heterocomplex of iron superoxide dismutases defends chloroplast nucleoids against oxidative stress and is essential for chloroplast development in Arabidopsis

There are three iron superoxide dismutases in Arabidopsis thaliana: FE SUPEROXIDE DISMUTASE1 (FSD1), FSD2, and FSD3. Their biological roles in chloroplast development are unknown. Here, we show that FSD2 and FSD3 play essential roles in early chloroplast development, whereas FSD1, which is found in the cytoplasm, does not. An fsd2-1 fsd3-1 double mutant had a severe albino phenotype on agar plates, whereas fsd2 and fsd3 single knockout mutants had pale green phenotypes. Chloroplast development was arrested in young seedlings of the double mutant. The mutant plants were highly sensitive to oxidative stress and developed increased levels of reactive oxygen species (ROS) during extended darkness. The FSD2 and FSD3 proteins formed a heteromeric protein complex in the chloroplast nucleoids. Furthermore, transgenic Arabidopsis plants overexpressing both the FSD2 and FSD3 genes showed greater tolerance to oxidative stress induced by methyl viologen than did the wild type or single FSD2- or FSD3-overexpressing lines. We propose that heteromeric FSD2 and FSD3 act as ROS scavengers in the maintenance of early chloroplast development by protecting the chloroplast nucleoids from ROS.     

Seed germination and seedling fitness in Mesua ferrea L. in relation to fruit size and seed number per fruit

Effect of fruit size and seediness (seed number per fruit) was examined on germination and early growth of seedlings in Mesua ferrea L. Fruiting incidence (number of fruited trees in a population) and fruit loading (number of fruits per tree) vary from one year to the other, and were greater in 1997 than in 1998. Seeds from large fruits (> 40 g) are preferred for forestry plantations and those from small fruits (< 40 g) are discarded, despite a greater proportion of small fruits (63.2 %) than large fruits (36.8 %). A fruit, large or small in size, may contain one, two, three or four seeds. The germination percentage of seeds increased from 1-seeded through 4-seeded fruits both in laboratory and greenhouse conditions, and both in case of large and small fruits. Conversely, the mean seed weight and germination time decreased along this gradient, i.e. seeds from 1-seeded fruits were the heaviest and required maximum time for germination, and the seeds from 4-seeded fruits were the lightest and required minimum time for germination. The seeds from small fruits were lighter in weight, achieved lower germination percentages and required greater germination time than the seeds from large fruits in all four seeded categories. Seedlings from seeds from 1-seeded fruits survived better and with stronger vigour after 1 year of growth than seedlings from 2-, 3- and 4-seeded fruits. Further, seedling survival and vigour were greater for seeds from large rather than small fruits.