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991.
Mode of inheritance of Alcobaca,a tomato fruit-ripening mutant 总被引:3,自引:0,他引:3
Summary
Alcobaca, an abnormally ripening tomato mutant, was crossed with the normal cultivar Rutgers. Examination of F1, F2 and BC1 populations indicated that a single recessive gene controls the mutant phenotype. No maternal effect was detected. 相似文献
992.
以脱羧腰果壳液制表面活性剂 总被引:1,自引:3,他引:1
采用天然植物油(脱羧腰果壳液CNSL)作为疏水基的,经由己二异氰酸酯与亲水基聚乙二醇在较为温和的条件下反应,制得了两亲性表面活性剂,表征了其表面性能。该类表面活性剂的三个样品的临界胶束浓度为0.35-0.5g/L,亲油亲水平衡点为15.5-16.0,浊点为70-80℃,临界胶束浓度下的表面张力(25℃)为28-35mN/m。该技术为腰果壳液的综合利用开辟了一条新的途径。 相似文献
993.
Commercially produced vegetative inocula of Laccaria laccata and Hebeloma crustuliniforme successfully formed ectomycorrhizae with Douglas-fir transplanted container (plug+1) seedlings. After 4.5 months in containers, 83% and 90%, respectively, of short roots were mycorrhizal. L. laccata- or H. crustuliniforme-inoculated seedlings had significantly more mycorrhizal and total short roots than Pisolithus tinctorius-inoculated (4% mycorrhizal root tips) or uninoculated control seedlings. No significant differences were detected in seedling growth at the end of the container phase.After transplantation and growth in nursery beds for 17 months, mean new short root colonization of all seedlings was 80%. H. crustuliniforme persisted as a dominant mycorrhizal fungus on seedlings initially inoculated with this fungus. L. laccata-inoculated seedlings had 40% of their short roots colonized by L. laccata and another 40% by native fungi Rhizopogon and Thelephora spp. All mycorrhizae of control seedlings and those inoculated with P. tinctorius were formed by fungi native to the nusery beds. A significant fungal treatment effect was detected for shoot height only. Control seedlings were significantly taller than L. laccata-inoculated seedlings after transplanting.This article is part of senior author's thesis in partial fulfillment of the Ph.D. degree in the Department of Forest Science at Oregon State University, Corvallis. 相似文献
994.
995.
996.
沙地杨树纸浆林栽培技术研究 总被引:3,自引:0,他引:3
为探索瘠薄干旱条件互氏浆林的栽培技术,选用4个杨树良和无性系,设计5种密度和4种整地,栽植深度,进行造林试验。结果表明:在平原沙地采是耐瘠薄的优良树品种,深栽70cm,适当密植,前两年实行林粮间作,以耕代抚,第3,4年雨季前各追施 化肥,5a生林分总蓄积可达77.41-182.56m^3/hm^2,净产值可达2620.5-7300.5元,其经济效益为纯农业的2.67-7.85倍。 相似文献
997.
Pekka Rossi 《New Forests》1991,5(3):211-218
The influence of length of cuttings on establishment of a short rotation plantation was investigated over a period of two years using direct field planting of unrooted Populus Rasumowskiana cuttings. The longer the cuttings, the higher were the survival and dry mass production. Survival at the end of the second growing season varied from 75% to 97%. In two years, the two longest cutting lengths (40 cm and 50 cm) produced about 100 g dry mass per living cutting; but owing to the higher survival rate of the longest cuttings, there was a difference per area unit: 360 g/m2 for 40 cm and 400 g/m2 for 50 cm-long cuttings. The shortest (10 cm) cuttings produced only 115 g/m2. 相似文献
998.
999.
This project was established in the Doce River Valley in the state of Minas Gerais, Brazil. The objective was to study the effect of intercropping one, two, three and four rows of maize between eucalypt seedlings planted in a 3.0×2.0 m spacing. Eucalypt data were collected at the age of six months when the maize was harvested. One row of maize intercropped between the rows of eucalypt did not lower the initial growth and survival of the trees, but did reduce the costs of the eucalypt plantations by 60%. Other treatments involving additional rows of maize reduced plantation costs, but also reduced the initial growth and survival of the trees. 相似文献
1000.