植物生长调节剂对龙眼内源激素及花芽分化的影响

研究了ＰＰ３３３和ＧＡ对龙眼（ＤｉｍｏｃａｒｐｕｓｌｏｎｇａｎａＬｏｕｒ）,成花的作用及其与内源激素的关系。结果表明,ＰＰ３３３处理后,ｉＰＡ含量明显高于ＧＡ的处理,而ＧＡ含量则呈现由高到低逐渐下降的趋势,ＧＡ处理正好相反,ＰＰ３３３处理后芽中的ＡＢＡ含量明显低ＧＡ处理,表明高含量的ＧＡ和ＡＢＡ不利于花芽分化,而高含量的细胞分裂素则有利于花芽分化,外施Ｐ３３３可缩短花序长度,提高着果率和增加产量。     

METABOLISM OF PLANT GROWTH REGULATORS

Comparison of the metabolism of ¹⁴C carboxyl-labelled 2,4-D in detached leaves of different varieties of apple showed that the 2,4-D-resistant Cox decarboxylated 57% of the 2,4-D in the leaf in 92 hr., whereas the susceptible Bramley's Seedling decarboxylated only 2% in the same time. Comparatively high rates of decarboxylation were found with all varieties of apple having Cox in their parentage; varieties unrelated to Cox showed low rates of decarboxylation. Similar high rates of decarboxylation were found in resistant varieties of strawberry and in Syringa vulgaris. Sixteen other species tested showed low rates of decarboxylation, irrespective of whether they were resistant or susceptible to 2,4-D.
The rate of decarboxylation of 2,4-D in the mature strawberry leaf was proportional to the amount of 2,4-D in the leaf. The rapid fall in decarboxylation rate in a detached leaf was due chiefly to reduction in the amount of 2,4-D present, and not to any falling off in the metabolic activity of the leaf. Young leaves decarboxylated 2,4-D at about half the rate of fully grown or senescent leaves. Oxidation of the methylene carbon proceeds at less than half the rate of that of the carboxyl carbon and is accompanied by an increase in the phenol content of the leaf which agrees closely with the amount of 2,4-D demethylated.
As previously reported for currants, part of the 2,4-D entering the leaf was bound and part inactivated by the formation of water-soluble compounds. The reaction of strawberry variety Talisman to 2,4,5-trichlorophenoxyacetic (2,4,5), 2-chloro-phenoxyacetic (2-CPA), 4-chlorophenoxyacetic (4-CPA) and 2-methyl-4-chlorophenoxyacetic (MCPA) acids was similar to that previously reported for red currant. Leaves of Cox's Orange Pippin apple and Talisman strawberry were able to decarboxylate all these phenoxy-acids except 2-CPA.     

THE RELATIONSHIP OF GIBBERELLIN AND AUXIN IN PLANT GROWTH

No synergism was found between IAA and gibberellin in the Avenucurvature test and this bioassay thus measures changes in diffusibleauxin resulting from gibberellin treatment and not a synergisticaction of the gibberellin on the curvature response to auxin.Gibberellin treatment causes an increase in diffusible auxinfrom the stem apex of dwarf pea (Pisum sativum L. var. LittleMarvel) 24 to 48 hours before the elongation response in thestem. The increase in diffusible auxin in the stem apex of Centaureacyanus L. var. Blue Boy occurs four to six days before the boltingresponse to gibberellin treatment under short days. The stemtissues of both the dwarf pea and Centaurea show an elongationresponse to IAA when the IAA is applied in a manner simulatingthe stem apex. Thus the growth of the dwarf pea and the boltingof Centaurea brought about by treatment with gibberellin aredependent on an increase in diffusible auxin. ¹Present address: Biological Institute, College of General Education,University of Tokyo, Komaba, Meguro, Tokyo.     

植物生长调节剂的研究及应用进展

植物生长调节剂是合成植物激素,其可以调节植物的代谢和生理功能,并且已广泛用于农业、林业和其他领域。而植物生长调节剂本身存在的毒副作用所引起的安全问题也不容忽视,在使用调节剂时应保证其安全性和有效性。文章概述了植物生长调节剂的种类、作用功效、国内外植物生长剂的研究和应用情况及在使用中存在的问题,分析了调节剂药效的影响因素,就植物生长调节剂的进一步应用提出了建议,进行了展望,并对其应用于生态修复领域的可行性进行了分析。植物生长调节剂在使用时应注意:(1)适时适量;(2)多种药型谨慎搭配,科学调控植物生长剂的使用;(3)植物生长调节剂不能随意与农药搭配以避免不良反应的发生。     

植物激素对锦橙留树保鲜及贮藏效果的影响

锦橙果实于采前9月中、下旬果面色泽由浓绿转为淡绿时,用15～30ppm GA 50ppm 2,4—D喷布果面,每月喷一次,共喷2～3次,能延缓果实的成熟,留树保鲜2～3个月,稳果率达93％,果实色泽鲜艳,可溶性固形物含量高,果肉细嫩,风味浓甜。本处理可使锦橙贮藏采收期由11月中旬延迟到12月底,贮藏到次年4月下旬,效果良好,腐烂、干疤率均低。     

EVALUATION OF PLANT GROWTH REGULATORS TO INCREASE NICKEL PHYTOEXTRACTION BY ALYSSUM SPECIES

Recent studies have shown that application of phytohormones to shoots of Alyssum murale increased biomass production but did not increase Ni shoot concentration. Increased biomass and Ni phytoextraction efficiency is useful to achieve economically viable phytomining. The objective of this study was to evaluate the effect of two types of phytohormones on the Ni phytoextraction capacity of four Alyssum species. Two different commercially available phytohormones (Cytokin® and Promalin®) based on cytokinins and/or gibberellins were applied on shoot biomass of four Ni hyperaccumulating Alyssum species (A. corsicum, A. malacitanum, A. murale, and A. pintodasilvae). Cytokin was applied in two concentrations and promalin in one concentration. The application of phytohormones had no clear positive effect on biomass production, Ni accumulation and Ni phytoextraction efficiency in the studied Alyssum species. A. malacitanum was the only species in which a significantly negative effect of these treatments was observed (in Ni uptake). A slightly positive response to promalin treatment was observed in the biomass production and Ni phytoextraction efficiency of A. corsicum. Although this effect was not significant it does indicate a potential application of these approaches to improve phytoextraction ability. Further studies will be needed to identify the most adequate phytohormone treatment as well as the appropriate concentrations and application times.     

生长调节物质对紫杉醇和紫杉烷类化合物合成的调控作用

植物生长调节物质不但控制细胞分裂,也影响着紫杉醇或紫杉烷类化合物的合成,５ｍｇ／Ｌ ＮＡＡ、１ｍｇ／Ｌ ＢＡ有利于紫杉愈伤组织的生长。随着ＢＡ深度伯提高,愈伤组织的增长率明显下降但是,其紫杉醇含量却有所增加。ＢＡ与ＮＡＡ的比例在有利于１０－去乙酰浆果赤霉素Ⅲ合成,添加高浓度ＧＡ５和ＣＣＣ均掏紫杉愈伤组织的生长,２ｍｇ／ＬＧＡ３、１ｍｇ／Ｌ ＣＣＣ有利于紫杉醇的合成。     

EFFECT OF AUXIN AND ANTIAUXIN ON CELL ELONGATION IN YEAST

By using a cytoplasmic mutant strain of yeast deficient in aerobicrespiration, it was demonstrated that, in the concentrationof 10–20 mg/l, indole-3-acetic acid and a.naphthaleneaceticacid promoted elongation of yeast cells, while acetic acid hadno such effect. An antiauxin, 2, 4, 6-trichlorophenoxyaceticacid, completely reversed the above-mentioned effect of auxin. The effect of auxin could be observed before any significantcell multiplication occurred. (Received February 7, 1963; )     

GROWTH REGULATION BY ETHYLENE IN FERN GAMETOPHYTES. I. EFFECTS ON PROTONEMAL AND RHIZOIDAL GROWTH AND INTERACTION WITH AUXIN

Three responses resulted from the treatment with ethylene of dark-grown gametophytes of Onoclea sensibilis. Elongation of the filament was increased, elongation of the rhizoid was decreased, and cell division was inhibited. The optimal ethylene concentrations were between 0.01 and 0.1 ppm. Filament elongation was very tolerant of high ethylene concentrations, since up to 1,000 ppm did not inhibit growth below control levels. Enclosing cultures of gametophytes in chambers of limited volumes produced all the effects of treatment with ethylene, but the responses to sealing were eliminated if plants were enclosed in a chamber which contained a solution of mercuric Perchlorate. This evidence that gametophytes produced ethylene was substantiated by a direct gas chromatographic demonstration of ethylene formation. The growth-regulating effects of ethylene and auxin appeared to be independent in filament and rhizoid growth. Inhibition of elongation by supra-optimal auxin concentrations could not be attributed to an auxin-stimulated production of ethylene.