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

1981 ◽  
Vol 37 ◽  
pp. 125-132 ◽  
Author(s):  
P L Pfahler
Keyword(s):  
Biological Activity ◽  
Environmental Pollutants ◽  
In Vitro Germination ◽  
Maize Pollen ◽  
Germination Characteristics

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

1980 ◽  
Vol 58 (5) ◽  
pp. 557-561 ◽  
Author(s):  
P. L. Pfahler ◽  
H. F. Linskens ◽  
M. Wilcox
Keyword(s):  
Pollen Tube ◽  
Calcium Nitrate ◽  
Pollen Grains ◽  
Tween 80 ◽  
Tube Length ◽  
In Vitro Germination ◽  
Sorbitan Monooleate ◽  
Germination Characteristics ◽  
Surfactant Effects

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 and pollen tube growth of maize (Zea mays) pollen. III. The effect of pollen genotype and pollen source vigor

1970 ◽  
Vol 48 (1) ◽  
pp. 111-115 ◽  
Author(s):  
P. L. Pfahler
Keyword(s):  
Pollen Tube ◽  
Calcium Nitrate ◽  
Pollen Grains ◽  
Germination Percentage ◽  
In Vitro Germination ◽  
Artificial Medium ◽  
Germination Characteristics ◽  
The Mean ◽  
Single Cross Hybrids

Pollen grains from three inbreds (H49, H55, and H50) and two of their single cross hybrids (H49 × H55 and H49 × H50) were cultured on an artificial medium containing 15% sucrose and 0.6% bactoagar supplemented with all possible combinations of two levels (0.00 and 0.03%) of calcium nitrate (Ca) and two levels (0.00 and 0.01%) of boric acid (B). For all characteristics measured (germination percentage, germination with more than one pollen tube percentage, rupturing percentage, length and growth rate of the pollen tubes), significant differences between inbreds were obtained on most combinations of Ca and B. Since the inbreds were presumably homozygous and, as a result, each produced pollen grains of only one genotype, these differences in germination characteristics were apparently produced by the genetic differences between the inbreds. Therefore, the in vitro germination characteristics of pollen grains are associated with pollen genotype. The response of the hybrids could not be accurately predicted from the behavior of their inbred parents. In general, the hybrid mean was in the range between the means for the two inbred parents. However, the value of the mean for the hybrid relative to the values of the parental means depended on which hybrid combination was involved. The results indicated that the germination characteristics of pollen grains on various combinations of Ca and B are influenced in large part by pollen genotype but that the genetic expression is quite complex. Vigor of the pollen source per se was not a factor.

In vitro germination and pollen tube growth of maize (Zea mays) pollen. IV. Effects of the fertility restoring Rf1 locus

1971 ◽  
Vol 49 (1) ◽  
pp. 55-57 ◽  
Author(s):  
P. L. Pfahler
Keyword(s):  
Pollen Tube ◽  
Calcium Nitrate ◽  
Pollen Grains ◽  
Germination Percentage ◽  
Tube Length ◽  
In Vitro Germination ◽  
Germination Characteristics ◽  
Bacto Agar ◽  
Pollen Tube Length

Pollen grains from the near-isogenic inbreds, Oh 43 Rf1Rf1, Oh 43 rf1rf1, 106 Rf1Rf1, and 106 rf1rf1 were cultured on an artificial medium containing 15% sucrose and 0.6% bacto-agar supplemented with all possible combinations of two levels (0.00 and 0.03%) of calcium nitrate (Ca) and two levels (0.00 and 0.01%) of boric acid (B). At certain combinations of Ca and B, significant differences between the Rf1Rf1 and rf1rf1 genotypes were obtained for germination percentage, rupturing percentage, and pollen tube length. However, the effect of the Rf1 and rf1 alleles was not consistent in magnitude for both inbreds. Apparently, the Rf1 and rf1 alleles can alter certain in vitro germination characteristics but genetic background is also involved.

In vitro germination protocol for the propagation of the endangered butternut tree (Juglans cinerea L.)

2019 ◽  
Vol 20 (2) ◽  
pp. 117-122 ◽  
Author(s):  
Martin Williams ◽  
Kathleen Forbes ◽  
Charlene Williams ◽  
Tannis Beardmore
Keyword(s):  
In Vitro Germination ◽  
Juglans Cinerea

COMPARATIVE STUDIES OF THE POTENTIATION OF CORTICOTROPHIN ACTIVITY BY SEVERAL INACTIVE DERIVATIVES

1963 ◽  
Vol 42 (2) ◽  
pp. 209-213 ◽  
Author(s):  
Arthur I. Cohen ◽  
Edward H. Frieden
Keyword(s):  
Biological Activity ◽  
Comparative Studies ◽  
Free Amino ◽  
Hormonal Activity ◽  
Amino Groups

ABSTRACT A number of corticotrophin analogues have been prepared, some of which potentiate the biological activity of the untreated hormone in vitro. The free amino groups of corticotrophin appear to be essential not only for hormonal activity, but also for the interaction of the analogues with the tissue corticotrophin inactivating system which is assumed to account for the potentiating effect.

Effect of C6-Volatiles on Bioluminescent Plant Pathogens

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 557d-557
Author(s):  
Jennifer Warr ◽  
Fenny Dane ◽  
Bob Ebel
Keyword(s):  
Biological Activity ◽  
Bacterial Growth ◽  
Xanthomonas Campestris ◽  
Plant Pathogens ◽  
Genetically Engineered ◽  
The Other ◽  
Computer Assisted ◽  
Signal Molecules ◽  
Low Concentrations

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.

Sign in / Sign up

Export Citation Format

Share Document