In vitro germination and pollen tube growth of maize (Zea mays) pollen. IX. Pollen source genotype and nonionic surfactant interactions

Abstract

Because of their structure and active metabolic state, pollen grains are vulnerable to any agent in the in vitro germination medium. Surfactants are used in biological systems to reduce surface tension but are also known to produce subtle biochemical effects. This study investigated the effect of three nonionic surfactants on the germination characteristics of pollen grains from three pollen source genotypes. Pollen grains from three single cross hybrids (Wf9 × H55, K64 × K55, Ky228 × Ky226) were cultured on an artificial medium (15% sucrose, 0.6% bacto-agar, 0.03% calcium nitrate, 0.01% boric acid) supplemented with all possible combinations of three concentrations (10, 100, 1000 ppm, v/v) of the following surfactants: (i) Tween 80 (polyoxyethylene sorbitan monooleate); (ii) X-114 (alkyl phenoxypolyethoxy ethanol); and (iii) commercial sticker spreader (alkyl olefin aromatic polymers). A control containing no supplement was included. Over all genotypes, increasing concentrations of Tween 80 had the least effect on the germination characteristics measured (germination and ruptured percent, pollen tube length at 1, 2, and 3 h after inoculation) and X-114 had the greatest effect with no germination found above 10 ppm. For most of the germination characteristics, highly significant pollen source genotype X concentration interactions were found for each surfactant. The direction and magnitude of the surfactant effects depended on the surfactant, its concentration, the germination characteristic involved, and the pollen source genotype.

In vitro Germination Characteristics of Maize Pollen to Detect Biological Activity of Environmental Pollutants

“…Gentile et al (25) avoided these limitations with maize pollen by placing the agent at a given concentration on the surface of the prepared medium and then allowing the agent to dry. However, pollen source genotype interactions with various concentrations of nonionic surfactants added directly to the medium have been reported in maize (20). Using this modification, a large number of pesticides and adjuvants were found markedly to reduce in vitro pollen germination and tube growth with concentrations having small effects as expected (25).…”

“…The effects of three nonionic surfactants on the germination characteristics of pollen grains from three pollen source genotypes were studied (20). However, they are known to produce subtle biochemical effects.…”

In vitro germination characteristics of maize pollen to detect biological activity of environmental pollutants.

“…Pollen source genotypes were included as part of this study (25) but their individual response patterns were not reported. However, pollen source genotype interactions with various concentrations of nonionic surfactants added directly to the medium have been reported in maize (20). The effects of various pesticides on in vitro pollen germination of other species have been examined with similar depressions in germination and tube growth found (26)(27)(28).…”

“…However, they are known to produce subtle biochemical effects. The effects of three nonionic surfactants on the germination characteristics of pollen grains from three pollen source genotypes were studied (20). Pollen grains from three single cross hybrids (Wf9xH55, Ky228xKy226, K64xK55) were cultured on a medium (15% sucrose, 0.6% bacto-agar, 0.03% calcium nitrate, 0.01% boric acid) supplemented with all possible combinations of three concentrations (10, 100, 1000 ppm v/v) of the following surfactants: Tween 80 (polyoxyethylene sorbitan monooleate); X-114 (alkyl phenoxypolyethoxy ethanol; and commercial sticker spreader (alkyl olefin aromatic poly-128 mers).…”