绿盲蝽的综合防治方法

绿盲蝽蟓又称牧草盲蝽,能危害多种果树、蔬菜、棉花、苜蓿等经济作物。 1危害特点及发生情况 1.1形态特征 绿盲蝽蟓属半翅目,盲蝽科。若虫体呈绿色,有黑色细毛,翅芽端部黑色;成虫体长约5毫米,呈绿色,前胸背板为深绿色,有许多小黑点。前翅基部为绿色,端部为灰色。     

淡娇异蝽生物学特性及无公害防治

对武义县板栗林中为害较为严重的淡娇异蝽30多年的观察和防治试验表明,淡娇异蝽1年1代,以卵越冬,越冬卵一般在2月下旬至3月上旬孵化,4月上中旬若虫开始为害嫩梢,5月中旬至6月上旬陆续进入成虫期,10月底或11月初开始产卵越冬;若虫发育历期34～61 d,3龄若虫对板栗危害最严重;成虫历期145～213 d;卵期102～135 d;无公害防治采取刮除卵块,石硫合剂喷雾,2.5%的溴氰菊酯、10%吡虫啉防治淡娇异蝽药效最好。     

绿盲蝽蟓在树冠内的空间分布及第1代若虫对枣股的危害规律

为有效控制绿盲蝽蟓Lygus lucorum Meyer-Dür的危害,在河北沧州金丝小枣产区对绿盲蝽蟓在树冠内的空间分布及第1代若虫对不同年龄枣股的危害规律进行了研究。结果表明:第1代若虫主要危害枣股,8~15 a生枣树的多年生枣股受害占受害枣股的40%以上。绿盲蝽蟓在树冠不同高度层对枣果造成的危害没有显著差异。在不同管理方式下绿盲蝽蟓对枣果造成的危害差异极显著,精细管理、粗放管理和对照的枣果受害率分别为13.96%,23.25%和41.68%。     

黄带犀猎蝽的生物学及应用研究

黄带犀猎蝽在广州室内饲养年发生2代,以4～5龄若虫于杂草丛生的石块、土块下或枯枝落叶层中越冬。卵成块,12.5～16.5天孵化。若虫5龄,历期48.0～223.5天。成虫羽化后5.0～12.5天交配,交配后11.5～25.5天产卵。成虫寿命一般在36.0天以上。若虫和成虫有较强的耐饥力,在缺少猎物时3～5龄若虫和成虫寿命分别为8.9～13.2天和17.3～20.2天。室内外捕食试验表明:对马尾松毛虫、纵带球须刺蛾、丽绿刺蛾、细皮夜蛾和竹斑蛾幼虫有较好的抑制作用。     

绿盲蝽成虫对枣树叶片、花蕾、幼果危害能力测定

为进一步了解绿盲蝽对枣树危害的严重性,在枣产区沧县高川乡朴寺村3 a生金丝小枣苗圃对其成虫危害枣叶、花蕾、幼果的能力进行了测定,结果为:绿盲蝽成虫每头每天平均危害枣叶2.46片,花蕾2.74个,幼果1.59个。     

不同宿主植物和饲养密度对蠋蝽生长发育和生殖力的影响

为促进蠋蝽规模化养殖,在室内测定不同宿主植物和饲养密度对蠋蝽若虫存活率、发育历期和成虫生殖力的影响,并利用Weibull分布函数S(t)=exp(-btc)拟合蠋蝽若虫在不同饲养密度下的存活率曲线。结果表明:蠋蝽若虫的存活率、发育历期和成虫生殖力因不同的饲养条件而异。宿主植物为榆树幼苗时,蠋蝽若虫存活率最高,平均为82.09%;无宿主植物时若虫存活率最低,平均仅达16.38%。不同宿主植物对若虫发育历期无显著影响,而无宿主植物时若虫发育历期延长。不同宿主植物对蠋蝽成虫生殖力影响显著,宿主为榆树时成虫产卵量最大,平均每雌产卵量可达330.89粒,无宿主植物时产卵量仅为96.64粒。以榆树作为宿主植物,不同饲养密度对蠋蝽若虫存活率影响较大,较低密度饲养时,其存活率差别不大,均达85.56%以上;但饲养密度超过每罩40头时,其存活率显著降低。不同饲养密度对蠋蝽若虫各龄发育历期的影响无规律。不同饲养密度对蠋蝽生殖力有不同程度的影响,密度过高或过低都显著降低其生殖力。     

不同虫态蠋蝽对黄栌胫跳甲幼虫的室内捕食反应

在天敌繁育室内研究蠋蝽Arma chinensis对黄栌胫跳甲Ophrida xanthospilota幼虫的捕食反应,功能反应试验数据用Holling方程分别进行模拟。结果表明:不同虫态蠋蝽的捕食量随黄栌胫跳甲幼虫密度的增加而增加,2～3龄蠋蝽若虫对跳甲1～3龄幼虫的捕食量高于对4～5龄幼虫的捕食量,4～5龄蠋蝽若虫和成虫对跳甲4～5龄幼虫的捕食量明显高于蠋蝽2～3龄若虫的捕食量。不同虫态蠋蝽捕食黄栌胫跳甲幼虫的圆盘方程能客观反映蠋蝽捕食量随黄栌胫跳甲密度变化而变化的情况;各虫态蠋蝽对跳甲1～2龄幼虫的控制作用差异不大,但蠋蝽4～5龄若虫和成虫对跳甲4～5龄幼虫的控制作用较2～3龄若虫更强。此结果可为野外释放蠋蝽防治跳甲提供依据,跳甲低龄幼虫期可释放2～3龄蠋蝽若虫,跳甲幼虫龄期较大时以释放4～5龄蠋蝽若虫或成虫为最佳。     

榕盲蝽危害特征及雌雄成虫性别鉴定

林间调查发现,高山榕盲蝽若虫及成虫以刺吸式口器群集于叶片取食,叶片被害处形成红褐色针头大小的坏死点,受害严重时,斑点连成一片,形成花斑,甚至全叶失绿变白。珠三角地区高山榕盲蝽发生普遍,该虫对高山榕株危害率达100%,叶片危害率高达80%以上。高山榕盲蝽自然种群性别比例为1∶0.33(237∶78)。体视显微镜下观察解剖榕盲蝽雌雄成虫发现:雌虫腹部较粗壮,腹部末端椭圆形,有少量刚毛分布。腹部末端有一细长"羊角状"黑褐色斑纹。雄虫腹部狭长,末端呈锤状。雄成虫腹部末端两侧对称黑斑间有一大一小倒三角形浅褐色斑。雄虫阳基侧突尖锥状。     

小皱蝽卵若虫发育起点温度及有效积温研究

小皱蝽CyclopeltaparvaDistant一年一代，是刺槐幼林枝杆的主要害虫，近几年在山东危害严重。1993～1994年为开展预测预报和综合治理提供依据，进行此项研究。1材料与方法1．1卵期从越冬后成虫6月中旬产卵始见期开始，每隔7d从林间采集一批当日产卵块，共5批，每批2个重复，每一重复100～393粒卵。卵块罩细纱网，在室内、林中自然变温培养，每天观察记录发育情况。1．2若虫期将越冬后成虫产卵孵化的同一批若虫，有1～5个龄期，每个龄期5个重复，每个重复若虫50～80头，用纱网罩在刺槐嫩枝上，林内自然变温培养，每天观察记录脱皮日期。1．3…     

赤峰市山杏上朝鲜球坚蚧的生物学特性研究

朝鲜球坚蚧在赤峰北部的生物学特性观察结果表明,该虫在林西县1年发生1代,以2龄若虫在蜡质覆盖物下越冬。翌年4月上旬开始出蜇并蜕皮进入3龄若虫期;雌雄成虫出现于5月中旬,雌雄性比为1∶1.25;雌成虫于5月下旬开始产卵,平均产卵量为714粒。当年若虫出现在6月初至7中旬,到10月上旬以2龄进入越冬状态。该虫对1~6年生山杏枝条均有危害,但主要危害2或3年生枝条。5月是该害虫危害严重的时期,应抓住越冬若虫出蛰进入3龄后迁移以及初孵若虫寻找寄生位置的阶段加以防治。     

Interspecific interactions alter root length density,root diameter and specific root length in jujube/wheat agroforestry systems

A field study was conducted at Hetian, southern Xinjiang, northwest China, to investigate root morphology as affected by interspecific interactions between jujube (Ziziphus jujuba Mill.) and wheat (Triticum aestivum L.). The treatments comprised (1) sole wheat, (2) 3-, 5- and 7-year-old sole jujube trees, and (3) intercropping of wheat/3-, 5- and 7-year-old jujube trees. Roots were sampled by auger in each plot down to 100 cm depth at 20 cm intervals in the soil profile and horizontally up to 150 cm away from the base of the trees at 30 cm intervals. All jujube/wheat intercropping systems had advantages of intercropping with a land equivalent ratio (LER) >1. There were significant differences in the contours of both root length density (RLD) and root diameter (RD) in intercropped wheat and jujube in the vertical and horizontal direction at corresponding soil depths but the RLD and RD of the 7-year-old jujube/wheat intercropping system were less influenced by intercropping in this respect than 3- and 5-year-old jujube intercropped with wheat. The roots of both intercropped wheat and jujube had smaller RLD, RD and larger specific root lengths (SRLs) at corresponding soil depths than did sole wheat and jujube. The older the jujube the larger were the SRL values of intercropped wheat and the smaller the RLD and RD of intercropped wheat. The greater the distance from the jujube the less influence there was on the RLD, SRL and RD of intercropped wheat and jujube and the greater the distance from the jujube the smaller was the SRL of intercropped wheat and the greater the RLD and RD of intercropped wheat (but still less than the monoculture wheat). The older the jujube the more developed were the jujube roots so that the smaller the SRL of jujube the bigger the RLD and RD of jujube. Jujube tree roots showed a mainly downward trend and extended laterally 150 cm from the trees resulting in the roots of the jujube trees and the wheat having niche overlap at a soil depth of 20–40 cm. The mechanisms underlying the thinner roots of wheat and jujube require further investigation.     

Root distribution and interactions in jujube tree/wheat agroforestry system

Even though agronomists have considered the spatial root distribution of plants to be important for interspecific interactions in agricultural intercropping, few experimental studies have quantified patterns of root distribution and their impacts on interspecific interactions in agroforestry systems. A field experiment was conducted to investigate the relationship between root distribution and interspecific interactions between intercropped jujube tree (Zizyphus jujuba Mill.) and wheat (Triticum aestivum Linn.) in Hetian, south Xinjiang province, northwest China. Roots were sampled by auger in 2-, 4- and 6-year-old jujube tree/wheat intercropping and in sole wheat and 2-, 4- and 6-year-old sole jujube down to 100 cm depth in the soil profile. The roots of both intercropped wheat and jujube had less root length density (RLD) at all soil depths than those of sole wheat and jujube trees. The RLD of 6-year-old jujube intercropped with wheat at different soil depths was influenced by intercropping to a smaller extent than in other jujube/wheat intercropping combinations. 6-year-old jujube exhibited a stronger negative effect on the productivity of wheat than did 2- or 4-year-old jujube and there was less effect on productivity of jujube in the 6-year-old system than in the 2- or 4-year-old jujube trees grown in monoculture. These findings may partly explain the interspecific competition effects in jujube tree/wheat agroforestry systems.     

Competitive interaction in a jujube tree/wheat agroforestry system in northwest China’s Xinjiang Province

The jujube tree (Zizyphus jujuba Mill.)/wheat (Triticum aestivum L.) agroforestry system is frequently used in China’s Xinjiang Province. The system improves land-use efficiency and increases economic returns. A field experiment was conducted at the Hetian oasis in southern Xinjiang Province to investigate the relationship between root distribution and interspecific interaction between the two intercropped species. The study included seven treatments: sole-cropped 5, 7, or 9-year-old jujube trees (treatments 1–3); 5, 7, or 9-year-old jujube trees intercropped with wheat (treatments 4–6); and sole-cropped wheat (treatment 7). To determine vertical root distribution, soil cores were collected in 20-cm increments from the 0 to 100-cm soil depth. The cores were collected at horizontal distances of 30, 60, 90, 120, and 150 cm from the jujube rows. The results showed that the land equivalent ratios were >1 for the three jujube/wheat intercropping systems. This indicated that these systems were advantageous compared with sole cropping. Tree height, breast height diameter, and mean crown radius were less in the intercropped treatments than in the corresponding sole-cropped treatments. Intercropping reduced the root length densities (RLDs) and root diameters (RDs) of both jujube and wheat at all soil depths. The RLD and RD of 9-year-old jujube trees were greater than those of the 5- and 7-year-old trees, which indicated that the root systems of the 9-year-old trees were more developed. Wheat root growth was inhibited more by older jujube trees than by younger ones. In conclusion, jujube tree/wheat intercropping can be practical and beneficial in the region. However, the mechanisms involved in the belowground interspecific interactions are still unknown. Additional research is needed to provide optimal management strategies and technologies for jujube/wheat intercropping.     

药用植物母猪果的生长发育特性

药用植物母猪果为山龙眼科山龙眼属的常绿阔叶树。2004年和2005年在云南省墨江县设置标准地和抽样调查得出:母猪果主要分布在海拔1600-2000 m,零星生长于常绿阔叶林和针阔混交林林地内;总状花序生于多年生枝条和树冠外围枝条的叶腋间,未开的花为浅黄色,开时为白色,具香味。花被4裂,雄蕊4枚,子房无毛,1室。果实为稍扁球形,果皮木质,内含1粒种子,花粉扁球形,极面观三角形边直或稍凹;花5-6月开放,果实发育从6月开始,生长较缓慢,到11月上中旬果实横径约1 cm左右;果实需到次年的5-6月才能成熟,在同一植株上可出现既有花又有果的现象。母猪果大小年结果和隔年结果现象极为明显,大部分植株当年结果后,次年就不开花结果。     

伐木联合机间伐作业性能和时间研究

本文介绍了伐木联合机间伐针叶林的时间研究过程和方法。通过欧洲赤松和落叶松的间伐试验、测量了单株作业时间和各动作时段比例。得到(?)SA250EVA型伐木联合机的生产能力为每小时57～68株或6.8～8.5m~3分析不树种、林木胸径及作业方式对伐木联合权作业性能的影响,作业评估表明,伐木联合机生产率高、工作条件舒适安全。对林木和林地捐伤小,适合在针叶林间伐中使用。     

节水栽培地幼龄枣树生长与发育规律

隔坡集蓄径流水平沟幼龄枣树的生长发育情况与以往鱼鳞坑和水平池方式有着明显不同。首先，在枣树根蘖苗成活率和保存率方面，前者极显著地高于后两者，成活率高达96．7％；其次在地上部和地下部的生长方面，前者的干径、枝展、枣头枝数、二次枝节数、根系总长、根系总重等方面均极显著高于后两者，这就决定了隔坡集蓄径流水平沟枣树丰产性能要远远高于鱼鳞坑和水平池，结果株率提高27．7％，结果吊率提高31．7％，坐果率提高3．36倍。另外、，沟间距以5m～6m为最好。     

Water deficits at anthesis reduce CO(2) assimilation and yield of lychee (Litchi chinensis Sonn.) trees

Ten-year-old 'Tai So' lychee (Litchi chinensis Sonn.) trees growing on a sandy loam soil in subtropical South Africa (latitude 25 degrees S) were watered weekly (well-watered treatment) or droughted from late July until January (drought treatment). After 16 weeks, at which time the trees obtained most of their water from below 150 cm, average soil water content at 0 to 150 cm depth was 14.5 +/- 0.1% in the well-watered treatment and reached a minimum of 7.6% in the drought treatment. At Week 7, minimum leaf water potential (Psi(L)) in the morning and early afternoon declined to -2.6 and -2.8 MPa, respectively, in droughted trees compared with -1.5 and -2.2 MPa, respectively, in well-watered trees. From Week 9, stomatal conductance and net CO(2) assimilation rate ranged from 70 to 300 mmol m(-2) s(-1) and 3 to 13 micro mol CO(2) m(-2) s(-1), respectively, in well-watered trees. The corresponding values for droughted trees were 50 to 180 mmol m(-2) s(-1) and 2 to 6 micro mol CO(2) m(-2) s(-1). Five weeks after rewatering the droughted trees, gas exchange had not recovered to the rate in well-watered trees, although tree water status recovered within a week of rewatering. In the well-watered trees, water use (E(t)) was 26 +/- 1 mm week(-1) with evaporation (E(p)) of 20 to 70 mm week(-1) indicating a crop factor (k(c) = E(t)/E(p)) of 0.4 to 1.2. Before anthesis, tree water status did not affect extension growth of floral panicles or leafy shoots. In contrast, no vegetative shoots were initiated after fruit set in the droughted trees when Psi(L) in the morning declined to -2.5 MPa. Water deficits reduced initial fruit set by 30% and final fruit set by 70% as a result of fruit splitting (41.2 +/- 4.0% versus 10.0 +/- 1.3%). Water deficits did not alter the sigmoidal pattern of fruit growth, but reduced yield from 51.4 +/- 5.5 kg tree(-1) in well-watered trees to 7.4 +/- 3.3 kg tree(-1) in droughted trees.     

枣树优良品种引种及选择试验

葫芦岛市于1994－1995年，分两批从山东、河北、河南等省引进18个枣树品种，分两处试验地进行栽培试验。结果表明，马连小枣、骏枣、灰枣、赞皇大枣产量明显高于对照品种，且表现较好，可在当地适量引进栽培；圆铃枣产量虽高，但自然成熟差，可引种驯化后再推广栽培；金丝小枣产量最低，不宜引种栽培。     

Observations on bark-stripping by red deer in a Picea sitchensis forest in Western Scotland over a 35-year period

The impact of bark-stripping by red deer on an 1825?ha plantation of Picea sitchensis is reported. Monitoring began in 1978 with initially 6500 trees at 37 sites; by 2014, only 10 sites remained due to felling. Sites became vulnerable to bark-stripping once the trees reached 7 years’ age, and from then until felling at age c. 45 years, incidence rates averaged 1% of the trees damaged yearly. Intense damage at a site in a year (>2% trees damaged) was often followed by intense damage next year, but, on average, 53% of sites were undamaged in a year. Many trees suffered repeat wounding, which reduced final impact by c. 30% compared to the theoretical impact calculated from annual damage and damage duration. The trees bark-stripped were on average smaller than plot mean girths once these means exceeded 20?cm; this had only a minor effect on the final impact since bark-stripped small trees had similar mortality to undamaged small trees. Most wounds (>90%) were small (<180?cm²) and healed quickly, so were unlikely to develop decay. Larger wounds never healed in less than 8 years, but the proportion healed increased progressively from 10 to 20 years after wounding.     

Photosynthetic and transpirational responses of red spruce understory trees to light and temperature

Understory red spruce (Picea rubens Sarg.) trees, between 20 and 50 cm in height and 12 years or more in age, were collected from mid- and high-elevation stands in north-central Vermont and placed in a closed-cuvette system to measure photosynthetic and transpirational responses to photosynthetic photon flux density (PPFD) and temperature. Photosynthesis, dark respiration, transpiration and water-use efficiency of trees from both stands responded to changes in PPFD and temperature in similar ways. Trees from both stands exhibited maximum rates of net photosynthesis at temperatures between 15 and 20 degrees C, and exposure to higher temperatures resulted in reduced rates of photosynthesis and increased rates of respiration. Net photosynthetic rates generally increased with increasing light intensity but began to level off at 250 micro mol m(-2) s(-1). Water-use efficiency was maximal when temperature and PPFD were at 15 degrees C and above 400 micro mol m(-2) s(-1), respectively.