国槐小卷蛾在石家庄地区的发生规律和行为观察

国槐小卷蛾是一种为害严重的钻蛀性害虫。为了掌握国槐小卷蛾在石家庄地区的发生规律和行为特征,采用野外调查和室内观察的方法,研究了国槐小卷蛾的生活史、生活习性和行为特征。结果表明:国槐小卷蛾幼虫常蛀食为害国槐和龙爪槐的羽状复叶叶柄基部、嫩梢、花穗和果荚等,严重影响树木的正常生长及观赏性。国槐小卷蛾成虫在石家庄地区1 a中有2次发生高峰,其羽化盛期分别为5月下旬~6月中旬和8月下旬~9月中旬。     

腰果叶片铁、锰和铜含量分布规律

[目的]检测腰果叶片中铁、锰和铜含量的分布规律.[方法]以海南稳定生产的腰果园为对象,系统布置采样点位,在年度生育期内采集叶片样品,分析腰果叶片的铁、锰和铜微量元素含量,明确其叶片铁、锰和铜微量元素含量分布规律.[结果]腰果叶片铁、铜和锰含量与其年度生育周期有关;10月份腰果树体生长开始活跃,为接下来的花芽分化和果实生长积累养分,其叶片微量元素含量逐渐增加,翌年3月份的坐果期养分消耗较大,其叶片养分含量逐渐降低.[结论]该研究为腰果的养分管理提供了思路.     

不同温度条件下油棕象甲实验种群生命表研究

在16、20、24、28、32℃5个温度梯度下,观察油棕象甲(Elaeidobius kamerunicus Faust)各虫态的生长发育历期和存活率,组建油棕象甲的实验种群生命表。结果表明,在16~32℃温度范围内,油棕象甲各虫态的发育历期随温度的变化而变化,在28℃时,油棕象甲各虫态及全世代的发育历期最短,存活率最高,产卵量最大。在16~32℃温度下,油棕象甲全世代平均发育历期分别为33.68、22.30、15.10、10.30和12.01 d。卵期、1龄幼虫、2龄幼虫、3龄幼虫、预蛹期、蛹期、产卵前期和全世代的发育起点温度分别为13.13、13.38、11.59、10.97、4.56、9.84、10.96和13.38℃;有效积温分别为13.57、13.44、18.79、25.53、79.11、47.62、25.98和214.09日度。种群趋势指数(I)在16~32℃温度范围内均大于1,内禀增长率(rm)均大于0,这说明油棕象甲的种群呈增长趋势。油棕象甲在28℃时种群趋势指数和內禀增长率最高,分别为18.944 2和0.285 6;其次为24℃,其生长发育及其繁殖的最适温区为24~28℃。     

西花蓟马孤雌产雄生殖繁育的后代种群生命表的建立

孤雌生殖是西花蓟马(Frankliniella occidentalis)繁殖的一种重要方式。前期研究发现,西花蓟马在高温下,雌性的存活率远大于雄性。为探究高温处理后仅有雌性西花蓟马孤雌产雄的情况下其后代建立种群的可能性,试验设定:高温(45℃,2 h)处理西花蓟马单个雌性个体,分别进行孤雌产雄生殖后,雄性子代(F1代)与其母系回交产生F2代;高温(45℃,2 h)处理西花蓟马多个雌性个体,进行孤雌产雄生殖后,雄性子代(F1代)与亲代多个雌性个体共存情况下进行交配产生F2代。两组处理模式下建立F2代实验种群生命表。结果表明,上述两种处理模式,母代雌性个体与子代雄性个体交配后均可产生后代,雄性F1代与其母系回交产生的F2代的雌雄性比为1.05∶1;与亲代多个雌性个体共存下交配产生的F2代性比为1.55∶1。雄性F1代与其母系回交产生的F2代的平均单雌产卵量(F)和内禀增长率(rm)显著小于与亲代多个雌性个体共存下交配产生的F2代(P0.05);各龄期的平均发育历期、平均产卵前期和平均总产卵前期2个繁殖力参数以及净生殖率(R0)、平均世代周期(T)2个种群参数,前者则比后者长(P0.05);另周限增长率(λ)两者之间无显著差异。研究表明西花蓟马在孤雌产雄状态下仍然可以在短期建立种群,具有较强的抗高温能力和繁殖能力,为其成功入侵奠定了生态学基础。     

赤峰市桑褶翅尺蛾生物学特性及防治对策

2012年以来,赤峰市阿鲁科尔沁旗桑褶翅尺蛾Zamacra excavata连续3a大发生,重度危害山杏Armeniaca sibirica灌木林。该文通过野外定位观察和查阅资料,对该害虫形态特征、生活史进行了描述,并提出了防治对策。     

鄂尔多斯成吉思汗陵周边野生种子植物区系研究

通过实地调查和文献资料查阅,对成吉思汗陵周边野生种子植物区系特征、生活型和水分生态型进行分析。结果表明:成吉思汗陵周边有野生种子植物529种隶属260属73科,分别占内蒙古种子植物的23.96%,39.82%,62.39%,在属、种层次上多样性较贫乏;植物科属组成特点是趋向大科、大属分布,寡种科属和单种科属是植物区系主要组成成分,也是植物区系构成和物种多样性的重要来源;区系地理成分混杂,联系广泛;属的分布区类型中温带成分优势明显,泛热带分布次之;特有程度低,表现出一定的古老性;植物生活型以草本植物占绝对优势,占总种数的86.39%;水分生态型以中生植物为主,占总种数的62.38%。     

Evaluation of annual wild <Emphasis Type="Italic">Cicer</Emphasis> species for drought and heat resistance under field conditions

About 90% of chickpea (Cicer arietinum L.) in the world is grown under rainfed conditions where it is subjected to drought and heat stress. Unlike the cultivated chickpea, annual wild Cicer species possess sources of resistance to multiple stress; annual wild Cicer species were therefore evaluated for resistance to drought and heat stress. Eight annual wild Cicer species (Cicer bijugum, C. chorassanicum, C. cuneatum, C. echinospermum, C. judaicum, C. pinnatifidum, C. reticulatum, and C. yamashitae) were compared with special checks, the cvs ICC 4958 and FLIP 87-59C (drought resistant) and ICCV 96029 (very early double-podded). ILC 3279 and 8617 as drought susceptible checks were sown after every 10 test lines. Yield losses due to drought and heat stress in some accessions and susceptible checks (ILC 3279 and ILC 8617) reached 100%. Accessions were evaluated for drought and heat resistance on a 1 (free from drought and heat damage)−9 (100% plant killed from drought and heat) visual scale. Four accessions of C. reticulatum and one accession of C. pinnatifidum were found to be as resistant to drought and heat stress (up to 41.8°C) as the best checks. C. reticulatum should be taken account in short term breeding programs since it can be crossed with the cultivated chickpea.     

近50年安徽淮北平原降水变化特征分析

选取淮北平原6个典型代表气象站的逐年降水观测资料,采用数理统计方法、趋势拟合和R／S分析等方法,分析了年降水量、主汛期降水量和暴雨日数的变化特征。结果表明,淮北平原年降水量和主汛期降水量增加并不明显,但年际间波动较大,年降水平均变异系数0．26,最大极差在1150mm以上;主汛期降水量变异系数0．39,极比达到5．07,导致旱涝频繁发生。趋势分析表明,20世纪90年代以来,淮北平原多雨年和少雨年都呈增加的趋势,暴雨日数也呈明显增多的趋势。R／S分析得出,未来淮北平原的降水仍呈宽幅震荡的趋势,旱涝灾害仍是制约当地农业生产的主导因素。     

Invasive and native plant responses to shrubland fuel reduction: comparing prescribed fire, mastication, and treatment season

Fuel reduction in the wildland-urban interface is a widely used international strategy for assisting human communities regarding wildfire threats, but very little research has examined whether certain fuel reduction methods and their seasonal timing promote nonnative invasion. To address this issue, we evaluated nonnative and native plant response to five of the most commonly-practiced shrubland fuel reduction methods in Mediterranean climates, including (a) fall prescribed fire, (b) winter prescribed fire, (c) spring prescribed fire, (d) fall mastication (slashing) and (e) spring mastication. Treatments were replicated four times in mature northern California chaparral and surveyed for three years after treatment; treatment type was randomly assigned. We found that the effects of treatment type (fire/mastication) were more apparent than the effects of treatment season (fall/winter/spring), but there were some differences among seasons of prescribed fire. Mastication treatments had the highest number of nonnative invasive species. Mastication treatments also had 34% higher nonnative annual grass abundance than the fire treatments. Winter and spring prescribed fire treatments were most resistant to nonnative invasion since these areas had the fewest nonnative species, lowest nonnative species abundances, and highest relative proportions of native plants. In shrublands where controlling nonnative annual grass is an important objective, managers should consider cool season prescribed fire as a viable fuel reduction treatment. In cases where prescribed fire is not feasible, mastication provides an alternative that can exacerbate nonnative grass production in the short term but may maintain native plant seedbanks over the long term if the site remains undisturbed for several decades. Results from this study could be applicable to other areas of Mediterranean shrublands.     

Genetic and phenotypic parameters and annual trends for growth and fertility traits of Charolais and Hereford beef cattle breeds in Kenya

This study estimated genetic and phenotypic parameters and annual trends for growth and fertility traits of Charolais and Hereford cattle in Kenya. Traits considered were birth weight (BW, kg), pre-weaning average daily gain (ADG, kg/day) and weaning weight (WW, kg); calving interval (CI, days) and age at first calving (AFC, days). Direct heritability estimates for growth traits were 0.36 and 0.21; 0.25 and 0.10; 0.23 and 0.13 for BW, ADG and WW in Charolais and Hereford, respectively. Maternal heritability estimates were 0.11 and 0.01; 0.18 and 0.00; 0.17 and 0.17 for BW, ADG and WW in Charolais and Hereford, respectively. Direct-maternal genetic correlations ranged between −0.46 and 1.00; −0.51 and −1.00; −0.47 and −0.39 for BW, ADG and WW in Charolais and Hereford, respectively. Genetic correlations ranged from −0.99 to unity and −1.00 to unity for growth and fertility traits respectively. Prospects for improvement of growth and fertility traits exist.