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71.
毛白杨,河北杨多代循环繁殖方法的研究 总被引:3,自引:1,他引:3
从1983年起,对毛白杨、河北杨的扦插繁殖育苗及其机理进行了研究,研究出“多代循环繁殖新方法”,无需任何处理,也无需地膜覆盖,使大田育苗成活率稳定在80%左右;同时研究出快速、简便、繁殖系数高的优树根萌条培育新技术,为毛白杨、河北杨优树的无性系测定、无性系育种和无性系造林创造了条件。 相似文献
72.
通过采取不同类型药剂防治松毛虫效果试验,结果表明,采用化学农药溴氰菊酯防治,灭虫率达98.4%~98.3%,但大部分松毛虫的天敌亦被灭杀,翌春复查,虫口密度3~5条.株-1,林分仍存潜在威胁;使用Bt生物杀虫剂和灭幼脲防治,灭虫率达99%以上,林中有益昆虫正常活动,翌春复查,虫口密度0~1条.株-1,可以看出:采用生物杀虫剂防治松毛虫效果最好,可有效杀死和消灭松毛虫,还不污染环境,不杀伤杀死各种农林作物害虫的天敌,对人畜均不构成危害。 相似文献
73.
74.
在预制建筑施工的发展过程中,建筑材料的选用对倾制房屋建造技术有着苇受的影响。通过对各种建筑材料的对比及特点分析,指出竹材人造板是一种具有很大发展潜力的预制房屋建筑材料。同时针对建筑行业实际应用巾的具体问题,对竹材人造板的发展提出了建议。 相似文献
75.
Mangal Singh M. S. Rathore D. Panwar J. S. Rathore H. R. Dagla 《Journal of Sustainable Forestry》2013,32(8):935-950
Aloe vera Linn. (Syn. Aloe barbadensis Mill; Gwar-patha in Hindi) belongs to family Liliaceae. The plant, for its medicinal properties, has commercial value. Some of the genotypes of Aloe vera are consumed as a vegetable and processed to make curry and other edible products. We report here on the development of an efficient method for rapid clonal propagation by shoot proliferation from axillary meristem(s) of selected germplasm of Aloe vera. Explants were pretreated with 0.1% aqueous solution of both streptomycin and bavistin separately, each for 15 min. These were surface sterilized with 0.1% aqueous solution of mercuric chloride (HgCl2) for 4–5 min and washed several times with autoclaved water. These were kept in a chilled, sterile antioxidant (200.0 mg L?1 of ascorbic acid, 50.0 mg L?1 of citric acid, and 25.0 mg L?1 of polyvinylpyrrolidone; PVP) solution and cultured on semi-solid Murashige and Skoog's (MS) medium. The bud explants produced multiple (10.3 ± 0.675/explant) shoots on MS medium containing 13.32 μM of 6-Benzylaminopurine (BAP) and 100.0 mg L?1 of ascorbic acid, 50.0 mg L?1 each of citric acid and PVP, with 25.0 mg L?1 each of arginine and adenine sulphate as additives. The shoots were further multiplied by (a) repeated transfer to fresh MS medium with additives + 13.32 μM BAP, and (b) subculturing on MS medium with a lower (4.44 μM) concentration of BAP. On MS medium containing 4.44 μM of BAP and additives, a maximum number (27.8 ± 0.63) of shoots were produced. In liquid MS medium with 4.44 μM of BAP, the rate of shoot multiplication increased and the vigor of the shoots improved. One hundred percent of the cloned shoots rooted under in vitro conditions on hormone-free half-strength MS salts containing 200.0 mg L?1 of activated charcoal at 32 ± 2°C. The cloned shoots treated with 2.46 mM of indole-3-butyric acid (IBA) or 2.473 mM of β-naphthoxyacetic acid (NOA) for 5 min rooted under ex vitro conditions in the greenhouse. The rooted plants were hardened in the greenhouse and stored under an agro-net house. The cloned plants were transferred under different field conditions at various sites in Western Rajasthan. These plants grew normally. The higher rate of shoot multiplication and easier approach of direct rooting and hardening make this method superior to the methods previously reported on cloning/tissue culture of Aloe species. From a single shoot bud, approximately 5000 plants can be produced within 180 days. 相似文献
76.
A micropropagation protocol was established for a medicinal plant Vitex negundo. Genetic stability of micropropagated plants was investigated. Multiple shoots were induced from nodal explants cultured on Murashige and Skoog (MS) medium with 0.53 μM naphthalene acetic acid (NAA) and 11.0 μM benzyl aminopurine (BAP) along with additives (ascorbic acid, 283.9 μM; citric acid, 130.1 μM; and arginine, 143.6 μM). Shoots were further multiplied by repeated transfer of the mother explant. The shoots were further multiplied on MS medium + 0.57 μM indole-3-acetic acid (IAA) and 6.6 μM BAP. The micropropagated shoots were pulse treated with 122.5 μM indole-3-butyric acid (IBA), in liquid MS medium and then transferred to autoclaved soilrite. These rooted ex vitro. Shoots were also rooted in vitro on a half-strength MS medium + 2.45 μM IBA. The survival rate of in vitro rooted plantlets was poor during hardening compared to ex vitro rooted plantlets. About 95% of the ex vitro rooted, hardened plantlets survived in the field. Genetic stability of micropropagated plants was tested by using 25 random amplified polymorphic DNA primers. The cloned plants exhibited no variation in banding pattern in comparison with the mother plant. 相似文献
77.
Mangal S. Rathore S. Shekhawat G. Kaur R. P. Singh N. S. Shekhawat 《Journal of Sustainable Forestry》2013,32(8):727-746
Withania coagulans (Stocks) Dunal (Solanaceae), popularly called vegetable rennet, is a critically endangered and highly valued medicinal plant. Overexploitation and reproductive failure forced the plant species toward the verge of complete extinction. We describe here the development of a simple, rapid, and cost effective in vitro micropropagation system for W. coagulans for mass-scale production of true-to-type plantlets using nodal shoot segments. Exactly 95.5 ± 0.34% explants responded within 8–10 days (d) and produced multiple shoot buds (4.1 ± 0.10 shoots of 2.95 ± 0.15 cm length) on 0.8% agar-gelled Murashige and Skoog's (MS) basal medium supplemented with 8.88 μM 6-benzylaminopurine (BAP), 0.57 μM indole-3-acetic acid (IAA), and additives (100 mg L?1 L-ascorbic acid, 25 mg L?1 each citric acid, adenine sulphate, and L-arginine). The shoots in cultures were multiplied by repeated transfer on MS medium with 4.44 μM BAP, 0.57 μM IAA, and additives. Further cultures were multiplied on a large-scale through the subculturing of shoot clumps differentiated in vitro, on MS medium supplemented with 1.11 μM BAP, 0.57 μM IAA, and additives. Maximum number (19.1 ± 0.28) of healthy (6.15 ± 0.25 cm) and viable shoots differentiated on this medium. The microshoots were rooted both in vitro and ex vitro. Exactly 67.3 ± 1.01% microshoots rooted in vitro within 25–30 d on agar-gelled half-strength MS salts supplemented with 29.52 μM indole-3-butyric acid (IBA) and 200 mg L?1 of activated charcoal (AC). Alternatively, 73.8 ± 0.65% cloned shoots rooted on sterile soilrite (soilless compost and soil conditioner) under ex vitro conditions after pulse treatment with 2.46 mM IBA for 300 s. The clones of W. coagulans were hardened in a greenhouse within 40–45 d by slow and gradual exposure of plantlets from high relative humidity (RH; 70–80%) and low (26 ± 2°C) temperature to low RH (40–50%) and high (34 ± 2°C) temperature. The hardened plantlets were transferred to soil and stored in agro-net house with more than 90% survival rate. Replacement of pure and laboratory grade sucrose with commercial grade sugar, use of less expensive commercial grade agar-agar in culture medium, higher rate of shoot proliferation, single step ex vitro rooting, and hardening of plantlets in the greenhouse are advantageous features of the protocol. The micropropagation protocol defined here is reproducible, easy to follow, and would be helpful in large-scale restoration programs through true-to-type mass-multiplication of W. coagulans. 相似文献
78.
79.
对福建柏1年生无性苗木用100 mmol.L-1NaCl进行胁迫处理,在处理60 d后对苗木的叶绿素、脯氨酸、可溶性糖、丙二醛等指标进行测定,结果表明:参试的福建柏无性材料间叶绿素含量、可溶性糖含量、丙二醛含量、脯氨酸含量等指标存在明显差异,且受遗传力制约,这些指标可作为抗盐无性系选育的依据;盐胁迫下309、327、328、381-2无性系的叶绿素、脯氨酸、可溶性糖含量分别比总体平均值增加了6.8%~57.1%、11.7%~17.3%、0.7%~14.5%,丙二醛含量减少了17.8%~56.8%。说明这4个无性系有相对较高的抗盐性,初步筛选出309、327、328、381-2抗盐无性系。 相似文献
80.
南方红豆杉扦插繁殖技术研究 总被引:6,自引:0,他引:6
2003~2004年应用2年生南方红豆杉幼苗进行扦插试验研究,结果表明:不同时间扦插的插穗生根时间最多相差2个月,2月中旬至3月中旬为最适宜扦插季节,扦插后3~5个月的生根率高于其它月份。用河沙与红泥作基质扦插,在不同季节扦插中以河沙作基质的生根效果比红泥的好。用生根剂处理有利于插穗提早生根及增加生根数量,以冬季及早春应用的效果较为明显,应用生根剂的插穗在扦插3~5个月后的生根率和生根数量与对照比有显著差异。不同类型插穗的扦插生根率在不同月份扦插的结果不同,但其差异不显著。 相似文献