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81.
Summary Experiments, performed withPinus pinaster cloned shoots submitted to an auxin treatment (NAA 10–6
M, 18 days), demonstrated that rooting abilityin vitro persists over 5 successive induction cycles (through out a 9-month period). Rooting ability needs a permanent synthesis of auxin synergists which activate the metabolism of cell dedifferentiation and root primordium initiation. Agar culture permitted intense meristem initiation, but prevented active root elongation. In the presence of a mycorrhizal fungus,Pisolithus tinctorius orHebeloma cylindrosporum, roots resumed growth and short lateral root formation was stimulated. These two phenomena induced by fungal association improve the quality of the root systems required to facilitate successful transplantation from test-tubes to field conditions. 相似文献
82.
Early 3rd instarDiacrisia obliqua Walk. larvae were treated with concentrations ofBacillus thuringiensis var.kurstaki (Dipel®) and the growth of treated larvae was assessed. All the doses reduced significantly the weight and survival of the insects (p<0.001). 相似文献
83.
在研究食品冷库中嗜冷微生物区系时,获得很多冷育型真菌。地丝霉和金孢菌类在这些菌中占优势。其中一菌在PYE上于18℃培养14天,菌落白色,厚毡状,中央常有淡黄色渗出液滴,菌落直径33mm,背面浅黄褐色,有辐射沟纹,老后仍为白色。菌丝分隔,直径1.0—2.0μm。该菌有明显的分生孢子梗,直立,宽度1.0—2.0μm,长10—25(—35)μm,无色或淡黄色,分生孢子梗具分枝,由分枝产分生孢子。分生孢子无色或淡黄色,顶端者为梨形、倒卵形或楔状,间生者矩椭圆形或桶状,1.5—2.5×2.5—3.5(—4.0)μm,光滑、1—3成链。该菌生长温度范围为0—25℃,最适温度为18℃,30℃不生长。此菌产生果胶酶,但是不分解角朊。该菌从冷库中生霉的蒜苗上分离得。其特征与Carmichael(1962),Domsch等(1980)所订正的金孢菌属(Chrysosporium Corda)中各种,以及Sigler和Carmichael(1976),Oorschot(1980)所订正的地丝霉属(Geomyces Traaen)中各种均有显著的差异,而其性状符合地丝霉属的特征集要。故命名为光滑地丝霉Geomyces laevis Z.Q.Li et Cui。模式:菌株AS 3.4605为模式菌株,保藏在中国科学院微生物研究所菌种保藏研究室;模式标本HMAS No.54875保存在该研究所真菌标本室。 相似文献
84.
本文报道了黑蛋巢菌属Cyathus四个新种和二个新变种,它们分别是:内蒙黑蛋巢菌Cyathus neimonggolensis Liu et Y.M.Li,盘柄黑蛋巢菌C.discostipltatus Liu et Y.M.Li,太原黑蛋巢菌C.taiyuanensis Liu et Y.M.Li,毛被黑蛋巢菌C.hirtulus Liu et Y.M.Li,天山黑蛋巢毛被变种C.tianshanensis Liu et Cao var.tomentosus Liu, Cao et Y.M.Li,环状黑蛋巢武夷山变种 C. annulatus Brodie var. wuyishanensis Liu et Y.M.Li。全部模式标本均保存在山西大学真菌标本室。 相似文献
85.
86.
Takuya Kajimoto 《Ecological Research》1989,4(1):55-69
Aboveground biomass and litterfall ofPinus pumila scrubs, growing on the Kiso mountain range in central Japan, were investigated from 1984 to 1985. The biomass of two research
plots (P1 and P2) with different scrub heights was estimated by two methods, the stratified clip technique and the allometric
method. Aboveground total biomass estimated by the latter method reached 181 ton d.w. ha−1 in P1 and 132 ton d.w. ha−1 in P2. Creeping stems contributed to about half of the total biomass. Although estimates of woody organs differed between
the two plots, leaf biomass estimates were almost the same at 15.5 ton d.w. ha−1. The canopies of the twoP. pumila scrubs were characterized by a large mean leaf area density of 5.0 m2 m−3. Despite this large area density, relatively moderate attenuation of light intensity was observed. Specific leaf area generally
increased with reduced leaf height. Annual total litterfall was estimated to be 3.60 ton d.w. ha−1 yr−1 in P1 and 2.39 ton d.w. ha−1 yr−1 in P2. Annual leaf fall in both plots was approximately 2.0 ton d.w. ha−1 yr−1. Leaves fell mainly in early autumn. Annual loss rates of branches, estimated as the sum of annual branch litterfall and
the amount of newly formed attached dead branches, were 0.29 ton d.w. ha−1 yr−1 in P1 and 0.37 ton d.w. ha−1 yr−1 in P2. 相似文献
87.
Cores were collected from dominant pondcypress trees growing in a swamp that had received sewage effluent for 7 yr and a nearby control swamp to determine the combined effects of changes in nutrient supply and hydrologic regime on tree growth. The cores were used to measure two indices of tree growth: basal area increment (BAI) and relative basal area increment (RBAI, which accounts for differences in growth due to the size of teh tree) between 1970–1983 while one swamp remained untreated and the other received weekly additions of sewage effluent from 1974–1981. Throughout the whole period, the mean BAI and RBAI of pond-cypress trees in the untreated swamp remained unchanged, ranging between 5.55–6.38 cm2 yr–1 and 1.09–1.27% yr–1, respectively. In contrast, trees in the treated swamp increased their BAI approximately two-fold from 7.40 cm2 yr–1 prior to treatment to 14.83 cm2 yr–1 after the onset of treatment and maintained this rate of growth in the 2 yr period after cessation of treatment. Relative basal area increment showed a similar response, but the proportional increase due to treatment was less (1.5-fold factor) than for BAI. The response of pondcypress trees to the sewage effluent differed depending upon whether the trees were located in the deep or shallow water zones. Trees in the deep zone of the treated swamp had lower BAIs and RBAIs than those in the shallow zone during the treatment period, whereas in pre- and post-treatment periods growth indices were equal in both zones. No significant differences in growth between deep and shallow zones were observed during all three time periods in the control swamp. 相似文献
88.
Anne Marpeau Jocelyne Walter Jacqueline Launay Jacqueline Charon Philippe Baradat Michel Gleizes 《Trees - Structure and Function》1989,3(4):220-226
Summary The effect of wounds on the volatile terpene composition of the living bark of Pinus pinaster Ait. (maritime pine) twigs was investigated with respect to the processes of mono- and sesquiterpene hydrocarbon biosynthesis. The large increase in the amounts of - and -pinene is a characteristic feature after a mechanical injury, whereas the quantities of the other terpenes are only slightly increased. This is due to the reactivation of the resin duct secretory cells of primary origin located in cortical tissues. The effect of wounding is observed over a long period and the terpene profiles are very different at the end of the experiments as compared with the initial profiles of the same tissues. The traumatic essential oil (obtained after mechanical traumatism) resembles an oleoresin extracted from tissues of secondary origin. Statistical analysis underlines the effects of the between-tree variations and of the dates of application of the wound. 相似文献
89.
Development of Bursaphelenchus xylophilus Populations in Wood Chips with
Different Moisture Contents
Bags of Pinus strobus wood chips with moisture contents of 38, 92, 164, and 217% (oven dry weight) were inoculated with Bursaphelenchus xylophilus and incubated at 30 C in order to determine the effect of wood moisture on nematode population development. Nematodes were extracted after 2, 4, 8, and 12 weeks. Population levels were greatest in wood chips with a moisture content of 38% and decreased successively with each higher moisture content. In chips with the three lower moisture contents, populations peaked at 2 weeks, but at 217% moisture, they peaked at 8 weeks. By 12 weeks, nematode populations had declined in wood chips with 92 and 164% moisture contents. The fungi most frequently isolated from the wood chips were Alternaria, Fusarium, Gliocladium, Graphium, Penicillium, Trichoderma, and Mucorales. 相似文献
90.
<正> 灌木,高约2米。小枝微弯曲,黑褐色,无毛。冬芽长卵圆形。叶片呈不等的五角形,长7—13匣米,宽8—16厘米,先端长渐尖,基部深心形,边缘有不等重锯齿,上面深绿色,散生硬毛,下面淡绿色,沿脉被短柔毛,主脉和侧脉均突起;叶柄长5—9.5厘米,近无毛。总状花序,下垂,花梗长3—4毫米,和总花梗均被短柔毛,常混生星状毛。果实长圆形,红色,直径约6毫米;萼片宿存,反折,近无毛。 相似文献