Plant growth inhibitory activity

Doi, F., Ohara, T., Ogamino, T., Sugai, T., Higashinakasu, K., Yamada, K., Shigemori, H., Hasegawa, K., Nishiyama, S. Plant-growth inhibitory activity of heliannuol derivatives. Phytochemistry 2004 65 1405-1411. 

Information on the structure-activity relationships of enantiomers of ipconazole as well as their fungicidal and plant growth inhibitory activities has been published by Saishoji et al. [72] and Ito et al. [73]. QSARs and three-dimensional shape studies of fungicidal azoylmethyl-cyclopentanols such as ipconazole and metconazole are available from Ref [70]. 

Table L Plant growth inhibitory activity of ABA analogs...

The growth-inhibitory activity of azadirachtin fed in artificial diet to three species of agricultural pests, gossypiella, H. zea, and frugiperda, was compared to the activity of a number of limonoids isolated from plants in the Meliaceae and the Rutaceae (Table VI). After azadirachtin, the most active limonoid was cedrelone (Figure 13). Cedrelone was unique among the compounds tested in Table VI since it was the only limonoid, besides azadirachtin, to cause an inhibition in ecdysis (LC50 = 150 ppm) when fed to pink bollworm larvae (54). 

Acetoxyodontoschismenol 74 (Scheme 12.13), a dolabellane diterpenoid, was isolated from the liverwort Odontoschisma denudatum and displayed moderate growth-inhibitory activity on a series of plant pathogenic fungi [37]. 

Other evidence suggesting the existence of growth inhibitors in plants came from analyses of acidic plant extracts by bioassay. This work indicated the presence of a zone in chromatograms with growth-inhibitory activity which was designated as inhibitor g. The most active component of inhibitor g was later shown to be ABA (15). 

BOA was first discovered by Virtanen and Hietala in 195739 as an anti-Fusarium compound in 4-days-old rye seedlings. Following this, different research projects were conducted to find the antipest significance of this compound in nature.18,38,40,41 In recent years the biological activity studies of BOA have also focused on plant metabolism inhibitory activity. A major part of these studies was based on the germination rate and on the root and shoot growth measurements of the species tested. 

A number of other llmonolds which were Isolated from plants In the Mellaceae and the Rutaceae were tested for ecdysis and growth Inhibitory activities (Table V). Cedrelone (Figure 9) was unique among the compounds tested In Table V since it was the only llmonold, besides azadlrachtln, whose toxicity (LC50 - 150 ppm) Included ecdysis Inhibition when fed to pink bollworm larvae (43). 

This discussion of vernolepin and jatrophone illustrates our approach to the isolation from plants of new, novel, and biologically active natural products. Both examples involved biological assays for growth-inhibitory activity, but any other satisfactory biological assay could be used in a search for other types of compounds. To the investigator who will undertake such a systematic approach to biologically active natural products,... 

M. salicifolia and displayed mosquitocidal activity on fourth instar Aedes aegyptii L. Culicidae at 15,25, 30,60, 80, and 100 ppm, respectively in 24 h [11, 12] (Table 2). Additionally, the sequential hexane, ethyl acetate, and methanol extracts of M. denudata and M. kobus var. stellata demonstrated growth inhibitory activity on gypsy moth larvae (Lymantria dispar) at 250 ppm [12], Citral and the phenylpropanoids are common in the essential oils of many plant genera. Citral, tram-anethole, and methyl chavicol have been detected in the essential oils of M. salicifolia and M. kobus [70, 71], Methyl eugenol has been detected in trace quantities by GC and MS in the leaf, branchlet, and essential oils from the flower bud of M. liliflora Desr. [72],... 

Phenylpropanoids have been known for numerous biological activities such as alleviation of fever, relief, antioxidative activity, growth inhibitory activity for spore of plant, or higher plant, insect attraction activity, and so on. 

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