黑松正常与异常球果的观察与分析

以烟台市栽培的绿化树黑松为材料,观察正常和异常幼果与近成熟球果着生状态,并对异常球果发生原因进行分析,结果表明:在原本属于小孢子叶球着生的当年生枝条基部着生着异常幼果(最多者为11枚)和近成熟异常球果(最多者为12枚),它们由小孢子叶球发生性反转途径转变为异常大孢子叶球进而发育为异常球果(不规则上下排列)。黑松正常幼果(球果)由大孢子叶球发育而来,着生在当年生枝条顶芽周围,呈环周式不等距同心圆水平排列;长椭圆形,中下部鳞脐平滑,上部略有凸起;一个枝条着生1~7枚不等,以4~5枚为主,稀1枚和7枚;与油松幼果有本质性遗传差异。     

红心杉不同无性系结实特性及球果类型分析

红心杉(Cunninghamia lanceolata)是广西重要的特色杉木种质资源,从挂果量、球果大小、苞鳞生长形态、球果长、球果宽、球果长宽比和单果鲜重等方面,对广西融水县红心杉专营种子园中的39个无性系的结实特性及球果类型进行分析。结果表明,红心杉挂果量具有明显的大小年现象。苞鳞松张、苞鳞紧包和苞鳞反翘3种形态在不同无性系中分布均匀,同一无性系的球果苞鳞形态较稳定,多数无性系球果类型为中果苞鳞紧包型。母树树体大小与苞鳞生长形态有极显著的相关性,高大母树和矮小母树球果主要呈苞鳞紧包和反翘,中等母树球果主要呈苞鳞松张和紧包。球果长、球果宽、球果长宽比和单果鲜重在不同无性系之间有极显著差异,聚类分析结果表明,无性系sy73和sy90球果体积较大,sy75和sy92球果体积较小,两者形状接近圆形,多数无性系球果体积中等呈长椭圆形。     

油松球果小卷蛾生物学特性及综合防治技术研究

油松球果小卷蛾是油松球果的主要害虫。通过对该虫生物学特性及防治技术研究表明,该虫在陕西秦岭林区1年发生1代,从老熟幼虫离开球果,吐丝坠地,在枯枝落叶层、杂草丛中及松土层内结茧化蛹越夏越冬。幼虫于5月上旬开始危害,取食嫩梢表皮、针叶及当年生球果,2 d后蛀入先年生球果隐蔽生活,取食果鳞基部和种子。采取林业防治、人工防治和药剂防治等综合技术措施,取得较好的防治效果。     

杉木应用全息定域选种育苗试验

植物全息定域选种是对林木个体内不同部位的这一层次上的遗传变异利用，是指从植物体的某一特定部位选留种子或枝条繁殖苗木的方法和技术。用种子繁殖苗木，须选取强遗传势的种子，其后代在生长量、质量和品种纯度等方面都优于其它区域种子，杉木是中部优势植物，其繁殖能力、结果性状的强遗传区在杉木主干的中部枝条。据陈晓阳研究杉木球果这一全息胚，不可育种鳞主要分布在球果的顶部和基部，其球果中部的可育种鳞出籽率最多，种子产生潜力最大，这一特性与杉木全株结实全息相关。     

落叶松球果瘿蚊生物学特性的研究

落叶松球果瘿蚊是落叶松的球果害虫,1年发生1代,老熟幼虫在表土层化蛹越冬。幼虫最先取食花蝇危害过的果鳞,随着虫龄增大,也危害健康的果鳞与种子。幼虫行动迟缓,终身在一个球果里取食,没有转移习性.林缘树上球果受瘿蚊危害比林内球果受害重.同一株树下部球果比上部球果被害重。阳面球果比阴面球果被害重。     

文冠果优良类型选择

以北京房山窦店9年生文冠果人工林为试验材料,以产量性状、品质性状,生长性状等为目标性状,开展以生态能源林为目标的优良类型选择。以植株花、果实等变异中较稳定的、容易识别的性状作为分类的依据,将文冠果初步划分为结实型和观花型2类。结实型主要是单瓣白花型。根据果实形状的不同,可进一步划分为小球果型、大球果型、圆柱果型、三棱果型、扁球果型、桃形果型、倒卵果型7类。利用层次分析法建立文冠果结实型优良类型评价指标体系,结果是小球果型综合性状最佳,是选优和推广优良类型,大球果型、圆柱果型次之。     

大果沙棘硬枝扦插育苗技术

大果沙棘硬枝扦插育苗 ,具有繁育方法简单、费用消耗少、繁殖系数高、可露地扦插等优点。但硬枝扦插育苗必须在拥有相当数量 2年生枝条情况下进行。其主要技术要点如下。枝条的选择　供硬枝扦插的枝条要在休眠期采集 ,即每年 2～ 3月份进行 ,选择健壮、高产、抗病性强植株的 2～ 3年生木质化枝条。据试验 ,插穗年龄对成海率有很大影响 ,3年生插穗成活率最高 ,2年生次之 ,1年生最低。枝条要采自树冠结实区 ,插穗长度以2 0～ 2 2cm为最佳。采下的成捆插条基部置于粗沙中贮存 ,插条上不覆盖任何物 ,沙子温度保持 1℃～ 3℃。插前处理　为提高成…     

班克松闭合型干型和湿型球果人工取种试验

通过对班克松闭合型干果和鲜果人工取种试验研究,结果表明：当年鲜球果和干球果在280℃高温条件下烘烤,种鳞开裂的时间分别为12s和10s;鲜球果高温开裂后,鳞片在12d之内张度达到5.1mm,种子从鳞片中脱出;干球果在高温开裂后,用喷水方法增加球果含水量,种鳞开张度达到10．2mm,种子脱出。     

华山松球果生命表研究

华山松是我国西南地区重要的造林树种之一,其球果从雌球花到球果木质化完成的整个发育过程中受到多种生物和非生物因素的影响.在云南省楚雄市紫溪山林场采种基地内球果死亡率达到47.6%,先后有败育、虫害、机械损失、冻害和鼠害5种致死因子导致华山松球果的脱落死亡.在5个致死因子中,虫害的致死力最强,致使球果死亡率达27.2%.由于虫害而损失的球果是其它致死因子造成落果总数的1.33倍.在种子园内造成落果的害虫主要有5种,1年生球果发育阶段,以球果花蝇和球果瘿蚊占主导地位;2年生球果发育阶段,微红梢斑螟的危害是造成落果的主要原因.     

油松球果小卷蛾防治技术

油松球果小卷蛾是我国松树上重要的嫩消和球果害虫，主要危害油松、马尾松、黑松、湿地松等，常与松实小卷蛾、芽梢斑螟混杂发生，竞相取食，严重影响松树生长发育，直接关系到天然林的更新和人工来种造林。在南方马尼松林内，4月上旬，马尾松雌球花顶部芽鳞张开，珠鳞呈茄红色时，油松球果小卷蛾幼虫开始钻蛀珠和珠心，雌球花逐渐萎缩，变成灰褐色，手提花碎。4月中旬始，幼虫侵害2年生膨大期的马尾松球果，以4月下旬至5月下旬危害最盛。幼虫多从球果基部下方蛀入，蛀食果轴周围的种鳞，蛀孔一边的种鳞先失级干枯，使整个球果呈黑褐僵硬，…     

日本落叶松种子园优良家系球花分布规律及花量调查

对日本落叶松种子园优良家系雌雄球花数量及在树冠上的分布规律进行调查分析。结果表明:日本落叶松雄球花在树冠垂直方向上分布差异极显著,下层和中层的数量显著多于上层,所占比例为83.39%,水平方向上南面的雄球花多于其他方向;雌球花在树冠不同冠层的分布无显著差异,中、上层的雌球花数量比下层多,东、南方向多于西、北方向;雄球花多着生在2,3 a生枝上,雌球花多着生在3,4 a生枝上,1 a生枝条上无花;不同无性系间雌雄球花数量差异显著,356号无性系的雌雄球花数量均为最多。     

Impact and control of the cone tortricid Pseudococcyx tessulatana (Staudinger), damaging the cone crop of a selected clone of cypress (Cupressus sempervirens L.) in Italy

The green cypress (Cupressus sempervirens) is of great interest for ornamental, reforestation and windbreak use in the whole Mediterranean basin. In Italy, seed material selected for resistance to the fungus Seiridium cardinale is produced in seed orchards by controlled crosses of parent trees. The insect pest showing the highest impact on seed cone production is Pseudococcyx tessulatana (Lep.; Tortricidae), which attacks cones during the initial growth period as well as full-grown cones. The impact on the seed cone crop of the tortricid was estimated on a clone patented for its resistance to cypress canker (Agrimed 1). The attack was inversely related to the cone crop, as it concerned 36.7?% of cones in 1999 (high crop year) and the 66?% in 2000 (low crop year). In both years, about 90?% of the surveyed branches revealed cones attacked by P. tessulatana by the 1^st life-cycle larvae, whereas only 40?% of branches were also attacked by the larvae of the 2^nd life cycle. The highest attack rate per branch was always observed on branches bearing a low number of cones. The potential of two control methods against P. tessulatana to protect cones which result from crossing a mother tree “Agrimed 1” with selected father trees was also evaluated in 2000. The protection given by a sleeve surrounding the branch was almost complete (0.4?% cone mortality), whereas a cone mortality of 24.3?% was observed on branches treated by the insecticide diflubenzuron. Sleeves appear to be useful to protect branches on which special crosses were done, but are expensive and time-consuming and may favour the attack of the mealybug Planococcus vovae inside the sleeve. The insecticide application may represent a valid alternative, especially when protection should be directed toward a high number of branches.     

Influence of male cones on early season vegetative growth of Pinus contorta trees

On average, branches of Pinus contorta Dougl. bearing male cones had 35 fewer needle pairs than equivalent vegetative branches, and significantly fewer differentiated primordia (i.e., male cones + needle pairs + sterile cataphylls). It was estimated that the formation of male cones results in a 27-50% reduction in the number of needles per male cone-bearing branch. In early spring, branches bearing male cones had on average 23% (0.44 g) more dry weight than vegetative branches. On average, 95% of the dry weight of male cone-bearing branches was allocated to the terminal shoot (54% of which was male cones) and 5% to the lateral shoots. By comparison, vegetative branches allocated 85% of their total dry weight to the terminal shoot and 15% to the lateral shoots. These findings suggest that male cones may reduce the photosynthetic potential of the trees which bear them.     

Influence of female cones on the vegetative growth of Pinus contorta trees

Branches of Pinus contorta Dougl. bearing two-year-old female cones initiated fewer lateral buds than vegetative branches. However, the number of lateral shoots that differentiated and grew was not reduced on female cone-bearing branches. Neither the number nor the weight of female cones influenced the length of the terminal shoot. The total length of all lateral shoots was positively associated with the weight of two-year-old female cones. Branch units with two-year-old female cones produced significantly more total dry weight in the current year than vegetative branch units. There was, however, no significant reduction in the dry weight of terminal and lateral shoots. Branches bearing female cones allocated between 17 and 45% of the current year's dry weight to two-year-old cones and between 1 and 5% was allocated to one-year-old female cones. Female cones therefore apparently do not reduce the photosynthetic potential of trees. The influence of female cones compared with male cones on the growth of trees is discussed.     

Effects of accelerated pollen-cone development on pollen cytology and fertilizing potential in western hemlock (Tsuga heterophylla)

Western hemlock (Tsuga heterophylla (Raf). Sarg.) pollen cones on cut branches were collected at different stages of development and maintained at room temperature in flasks of water to accelerate pollen-cone development and produce forced pollen. Accelerating pollen-cone development at early developmental stages reduced the number of cones that matured, decreased the quantity of pollen produced, increased the proportion of abnormally developed pollen and reduced the fertilizing potential of the pollen, as determined by seed efficiency. If the branches were collected after the pollen cones were at least 50% emerged beyond the bud scales, pollen-cone development could be successfully accelerated without decreasing pollen yield or fertilizing potential. Pollen collected from cones which were accelerated at early stages and stored for two years had a lower fertilizing potential and produced fewer seeds per cone than either unstored pollen or stored pollen collected from cones accelerated at later stages of development. The feasibility of accelerating pollen-cone development to ensure adequate supplies of pollen for controlled crosses or supplemental mass pollination is discussed.     

果梢斑螟对马尾松球果和雄花序枝生长发育的影响

果梢斑螟Dioryctria pryeri Ragonot是我国马尾松雄花、球果和枝梢的重要钻蛀性害虫。幼虫钻蛀主梢,引起枯萎,树干弯曲,影响高生长和材质;钻蛀雄花枝,引起雄花枯萎,影响雌花受粉,雄花枝遭蛀大量折断后,枝基当年萌芽,形成众多的细枝,钻蛀球果,引起萎蔫、落果,造成马尾松种子园种子产量严重歉收。果梢斑螟在浙江省一年一代,以幼虫越冬。翌年3月上旬至5月中旬,是马尾松雄花含苞、开放和二年生球果逐渐膨大时期,果梢斑螟越冬幼虫随即蛀入雄花序枝和球果,但有关该虫对马尾松球果、雄花序枝生长发育的影响迄今未见报道。本文旨在探索果梢斑螟危害对马尾松增枝、枝的生长量等的关系,为确定该虫的防治指标的研究提供参考依据。     

华北落叶松传粉生物学的研究

本文研究了华北落叶松雌雄球花在树冠上的分布和树冠周围花粉密度变化规律、传粉机制、胚珠接收花粉量及结实状况等。雌球花主要分布在树冠中上部2－4龄枝上，雄球花分布范围较广，且常与雌球花混生；树冠周围花粉密度与雄球花的分布密切相关，中部最大，依次向上下两端减少。依据雌球花形态特征的变化，可将传粉期为5个阶段，整个期间无传粉滴出现，由球被顶端大裂片的珠被毛接收花粉。最佳传粉期约为2天。胚珠平均接收4粒花粉，虽然胚珠接收的花粉数与饱满种子的产量有一定的关系，但并不是造成空粒的主要原因。此外，讨论了不同授粉方式对种子产量的重要意义。     

榆林沙区班克松物候及年生长规律观测

对榆林沙区2009年引种栽培的班克松进行了连续3年的物候及年生长规律观测。结果表明:班克松在榆林沙区4月上旬芽膨大,4月下旬至5月下旬主梢、枝生长旺盛,年平均生长量主梢47.7cm、侧枝19.9cm,6月中下旬芽完全形成。4月底至6月中旬针叶生长,平均2.63cm。雄球花5月初散粉高峰期,雌球花4月底5月初授粉。5月上中旬幼果形成,二年球果4月底至5月底生长迅速,平均纵径34.15cm,横径17.13cm,9月中旬球果成熟。     

世界级极危物种———崖柏球果特征与出种量的研究

通过对崖柏球果的长度、宽度和质量以及出种量的调查和统计分析发现,崖柏天然分布的雪宝山和大巴山两个不同地域崖柏球果的长、宽以及风干质量之间不存在显著差异,而同一地域不同崖柏植株之间的球果特征存在显著差异.在崖柏球果中,无种子的球果占7.1%;每个球果的出种量较少,仅为3粒;崖柏种子的千粒质量为1.126 4 g;同一崖柏植株不同球果之间的出种量没有明显差异,说明同一植株的有性生殖过程是同步的,球果的发育程度比较接近.