Effects on seed germination

The various fumigants often exhibit considerable specificity toward insect pests, as shown in Table 8. The proper choice for any control operation is determined not only by the effectiveness of the gas but by cost safety to humans, animals, and plants flammabdity penetratabdity effect on seed germination and reactivity with furnishings. The fumigants may be used individually or in combination. Carbon tetrachloride has been incorporated with carbon disulfide, ethylene dichloride, or ethylene dibromide to decrease flammability, and carbon dioxide is used with ethylene oxide for the same purpose. 

Various assay methods have been used to detect the presence of inhibitory substances. These include some of the classical tests used by investigators of growth-promoting substances—i.e., the various Avena coleoptile assays which utilize intact, decapitated, or isolated cylinders and the split pea stem test. Effects on seed germination and seedling shoot or root growth and development have also been measured in addition to other visible expressions of inhibition. Details of many of these tests have been compiled by Mitchell et al. (99). Tests have been carried out in Petri dishes, with various solution culture techniques, and by sand and soil culture. Effects so measured may or may not be similar to those obtained under field situations— i.e., the establishment of inhibition under controlled conditions pro-... 

Aerial portions contained more extractable inhibitory substances than did the roots. Seed germination of tall fescue, ball clover, sericea (Lespedeza cwneflW (Dumond) G. Don) and Kobe lespedeza Lespedeza striata (Thumb) H. and A.) were inhibited by extracts of pepperweed. The toxic substance(s) was present in all parts of the plant, and was toxic to crownvetch at a concentration of 1 150. The extracts were also toxic to five species of fungi. When pepperweed residues were mixed with soil there was no effect on seed germination, but seedling growth was retarded. The authors were of the opinion that the toxicity of pepperweed may be of significance in its competition with other plant species. 

Cutillo, F., D Abrosca, B., DellaGreca, M., DiMarino, C., Golino, A., Previtera, L. Zarrelli, A. (2003) Cinnamic add amides from Chenopodlum album effects on seeds germination and plant growth. Phytochemistry 64, 1381-1387. 

Alantolactone was reported to have strong inhibitory effects on seed germination and seedling growth. 

Aflatoxins have been found to have little effect on seed germination in most species, but post-germination, developmental responses may vary (Crissan, 1973 Llewellyn et al., 1982). Walker et al. (1985) have reported active uptake of aflatoxin (AFB ) by cultured soybean roots suggesting the possibility of contamination of the crop when it is grown on contaminated soils. 

M. J. Krogmeier and J. M. Bremner, Effects of phenolic acids on seed germination and. seedling growth in soil. Biol. Fertil. Soil ftll6 (1989). 

Effects of Sesquiterpene Lactones on Seed Germination. Sesquiterpene lactones are common constituents of the Asteraceae but are also found in other angiosperm families and in certain liverworts (31,32). These highly bitter substances exhibit a wide spectrum of biological activities (J 3) which include cytotoxicity, anti-tumor, anti-microbial, insecticidal (34) and molluscicidal (35) properties. Furthermore, they are known causes for livestock poisoning and contact dermatitis in humans (33). Structure-activity relationship studies on sesquiterpene lactones have demonstrated that biological activity frequently depend on the presence of the cr... 

Table II. Effects of Palmer Amaranth (Amaranthus Palmeri) Extracts on Seed Germination... 

Table III. Effects of Isolated and Identified Chemical Constituents of Palmer Amaranth on Seed Germination...

Table IV. Effects of 1 Hour Pretreatment with Diehloromethane on Seed Germination Percentages...

While the DCM pretreatment itself had no significant effect on the germination of the amaranth seed over 7 days, the chondrillasterol produced the effects observed in Table V. The effects of... 

Table V. Time-Course Study of Effects of Chondrillasterol on Seed Germination in Amaranthus Species...

Table VII. Effect of Ragweed (Ambrosia artemisiifolia) Aqueous Leaf Extract on Seed Germination... 

Table IX. Effects of Sesquiterpenes (MW 204) Isolated from Ragweed on Seed Germination... 

Bioassay on Solid Medium. A-9, a medium previously shown to be favorable for antibiotic production by actinomycetes in shake flasks (36), was modified for bioassays on solid medium. We halved the concentration of components in A-9 and adjusted the pH to 6.9-7.1 with KOH to reduce the possibility of osmotic or toxic effects of medium components themselves on seed germination and seedling growth. The medium was amended with 15 g agar per liter and poured into 10 x 10 x 1.5 cm square plastic petri dishes, about 60 ml per plate. 

Much remains to be accomplished in the separation, isolation, and identification of both naturally occurring and synthetic bioactive materials effective in the germination of parasitic weed seeds. Structure-activity studies suffer from the lack of separation of isomers in most synthetic samples. Strigol is an important tool in basic studies on the effect of chemicals on seed germination, but it is highly unlikely that the compound will meet practical field... 

Malinconico M, Immirzi B, Massenti S, La Mantia FP, Mormile P, Petti L (2002) Blends of poly-vinylalcohol and functionalized polycaprolactone. A study on the melt extrusion and post-cure of films suitable for protected cultivation. J Mat Sci 37 4973 1978 Mallek SB, Prather TS, Stapleton JJ (2007) Interaction effects of Allium spp. residues, concentrations and soil temperature on seed germination of four weedy plant species. Appl Soil Ecol 37 233-239. doi 10.1016/j.apsoil.2007.07.003... 

Mallek SB, Prather TS, Stapleton JJ (2007) Interaction effects of Allium spp. residues, concentrations and soil temperature on seed germination of four weedy plant species. Appl Soil Ecol 37 233-239... 

This work describes the application to soil of compounds of a previous study (11) which dealt primarily with organic synthesis and physical properties of reaction products of pure fatty acids with BETA. In this study derivatives were prepared from various industrial fatty materials. In addition, water infiltration studies on sand, sandy soil, and clay soils were carried out on the previously prepared and new compounds. Finally, an investigation was initiated to determine the biological effects of one water-repelling chemical, the partially hydrogenated tallow-fatty acid-DETA reaction product, on seed germination and plant growth. 

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