Temperature-Dependent Growth Model for Eggs and Larvae of Cephalcia arvensis (Hymenoptera: Pamphiliidae)

A set of density-dependent growth and survivorship equations is derived from evidence that the instantaneous death rate in the sea is inversely proportional to particle size. The survivorship equation reproduces several well-known phenomena observed in fish populations. It predicts: 1) that winter and spring spawning species ought to produce larger eggs than summer spawners, 2) that it is advantageous for species that spawn in batches to produce progressively smaller eggs in spring and summer, and 3) that the death rate of a cohort of fish should decrease continuously as the survivors grow and approach the critical size.The biological basis for the observed variation in the size of pelagic fish eggs and larvae is thought to be due primarily to trophic relations within the pelagic community. It is suggested from what is known of the relative abundance and foraging capabilities of different sized particles, that the survival rates of larval and juvenile fish should increase as they grow and occupy a progressively higher position in the food chain.

Download Full-text

Temperature-dependent growth and consumption of young-of-the-year sablefish Anoplopoma fimbria: Too hot, too cold or just right?

Fisheries Research ◽

10.1016/j.fishres.2018.09.005 ◽

2019 ◽

Vol 209 ◽

pp. 32-39 ◽

Cited By ~ 2

Author(s):

Joseph R. Krieger ◽

Ashwin Sreenivasan ◽

Ron Heintz

Keyword(s):

Temperature Dependent ◽

Anoplopoma Fimbria ◽

Young Of The Year ◽

Dependent Growth ◽

Just Right

Download Full-text

KEX2 mutations suppress RNA polymerase II mutants and alter the temperature range of yeast cell growth

Molecular and Cellular Biology ◽

10.1128/mcb.9.6.2341-2349.1989 ◽

1989 ◽

Vol 9 (6) ◽

pp. 2341-2349

Author(s):

C Martin ◽

R A Young

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Single Gene ◽

Yeast Cells ◽

Temperature Sensitive ◽

Temperature Dependent ◽

Growth Properties ◽

Cold Sensitive ◽

Dependent Growth ◽

Kex2 Protease

Suppressors of a temperature-sensitive RNA polymerase II mutation were isolated to identify proteins that interact with RNA polymerase II in yeast cells. Ten independently isolated extragenic mutations that suppressed the temperature-sensitive mutation rpb1-1 and produced a cold-sensitive phenotype were all found to be alleles of a single gene, SRB1. An SRB1 partial deletion mutant was further investigated and found to exhibit several pleiotropic phenotypes. These included suppression of numerous temperature-sensitive RNA polymerase II mutations, alteration of the temperature growth range of cells containing wild-type RNA polymerase, and sterility of cells of alpha mating type. The ability of SRB1 mutations to suppress the temperature-sensitive phenotype of RNA polymerase II mutants did not extend to other temperature-sensitive mutants investigated. Isolation of the SRB1 gene revealed that SRB1 is KEX2. These results indicate that the KEX2 protease, whose only known substrates are hormone precursors, can have an important influence on RNA polymerase II and the temperature-dependent growth properties of yeast cells.

Download Full-text

Pythium myriotylum is recovered most frequently from Pythium soft-rot infected ginger rhizomes in China

Plant Disease ◽

10.1094/pdis-05-21-0924-re ◽

2021 ◽

Author(s):

Paul Daly ◽

Yifan Chen ◽

Qimeng Zhang ◽

Hongli Zhu ◽

Jingjing Li ◽

...

Keyword(s):

Severe Disease ◽

Zingiber Officinale ◽

Soft Rot ◽

Temperature Dependent ◽

Pythium Myriotylum ◽

Disease Symptoms ◽

Ginger Rhizome ◽

Oomycete Pathogen ◽

Dependent Growth ◽

Pythium Soft Rot

Pythium soft rot is a major soil-borne disease of crops such as ginger (Zingiber officinale). Our objective was to identify which Pythium species were associated with Pythium soft-rot of ginger in China, where approximately 20% of global ginger production is from. Oomycetes infecting ginger rhizomes from seven provinces were investigated using two molecular markers, the internal transcribed spacer (ITS) and cytochrome c oxidase subunit II (CoxII). In total, 81 isolates were recovered and approximately 95% of the isolates were identified as Pythium myriotylum and the other isolates were identified as either P. aphanidermatum or P. graminicola. Notably, the P. myriotylum isolates from China did not contain the SNP in the CoxII sequence found previously in the P. myriotylum isolates infecting ginger in Australia. A subset of 36 of the isolates was analyzed repeatedly by temperature-dependent growth, severity of disease on ginger plants and aggressiveness of colonization of ginger rhizome sticks. In the pathogenicity assays, 32/36 of the isolates were able to significantly infect and cause severe disease symptoms on the ginger plants. A range of temperature-dependent growth, disease severity and aggressiveness in colonization was found with a significant moderate positive correlation between growth and aggressiveness of colonization of the ginger sticks. This study identified P. myriotylum as the major oomycete pathogen in China from infected ginger rhizomes and suggests that P. myriotylum should be a key target to control soft rot of ginger disease.

Download Full-text