scholarly journals Depression by inbreeding after four sucessive self-pollination squash generations

2004 ◽  
Vol 61 (2) ◽  
pp. 224-227 ◽  
Author(s):  
Antonio Ismael Inácio Cardoso
Keyword(s):  
Regression Analysis ◽  
Seed Production ◽  
Inbreeding Depression ◽  
Seed Quality ◽  
Inbreeding Coefficient ◽  
Cucurbita Moschata ◽  
F1 Hybrid ◽  
Self Pollination ◽  
Parental Lines ◽  
Level Effect

The strategy for breeding F1 hybrid squash is to develop parental lines through self-pollination. However, it increases plant mean homozygosis, which is not the natural genetic state of a cross-pollinated species, and can cause "inbreeding depression". The objective of this work was to evaluate this depression with sucessive generations of self-pollination (without selection) in Cucurbita moschata, cv. Piramoita. Populations were obtained from lines with one to four generations of self-pollination (obtained by the SSD method), from the original cv. Piramoita (population S0). Randomized blocks were used with five treatments (different generations of self-pollination - S0 to S4), six replicates and five plants per plot. Regression analysis was made by the Wright inbreeding coefficient (F) to measure the homozygosis level effect on vigor loss. There was a linear reduction of mean weight and fruit length, seed production (number and weight) per fruit with the increase of the homozygosis level; however inbreeding did not affect seed quality (weight of 100 seeds and germination).

scholarly journals Inbreeding Depression of Progenies of Castor Bean, From of the Variety FCA-PB, Results of Three Types of Pollinations

2019 ◽  
Vol 11 (16) ◽  
pp. 68
Author(s):  
Jackson da Silva ◽  
Andréia Rodrigues Ramos ◽  
Deoclecio Jardim Amorim ◽  
Maurício Dutra Zanotto ◽  
Maria Márcia Pereira Sartori
Keyword(s):  
Inbreeding Depression ◽  
Castor Bean ◽  
Inbreeding Coefficient ◽  
Genetic Aspect ◽  
Self Pollination ◽  
Lower Productivity ◽  
Grain Productivity ◽  
Wide Range ◽  
Productivity Variable ◽  
Coefficient Of Inbreeding

Oil of castor bean despite its wide range of use, still present a relevant deficit in the Brazilian market. This deficit could be softened or extinguished with increased productivity, in which the genetic aspect has a great contribution. The most productive genotypes are the hybrid varieties, however for obtaining the hybrids pure lineages are required which have appropriate agronomic characteristics and that express the minimum of inbreeding depression. Thus, the objective of this research was to evaluate the inbreeding depression of castor bean progenies, from the cultivar FCA-PB, resulting from three types of pollination. The experiments were implanted in design in randomized blocks, in the 30 × 3 factorial scheme, being 30 progenies and 3 types of pollination (free, cross and self-pollination), in 2 environments (São Manuel and Araçatuba) and in 2 crops (2004/2005 and 2005/2006), with three replications. Inbreeding depression was estimated under the grain productivity variable. It was observed that cross-pollination presented grain productivity close to 2500 kg ha-1, in which the lowest coefficient of inbreeding was determined, zero (0). Opposed It self-pollination, in which resulted in lower productivity, around 2000 kg ha-1, and the highest inbreeding coefficient being of 0.77. The reflection of the coefficient of inbreeding on productivity presents inversely proportional behavior, ie, the measure that increases the coefficient of inbreeding decreases the grain yield.

Mixed mating in Banksia media

2002 ◽  
Vol 50 (5) ◽  
pp. 627 ◽  
Author(s):  
S. J. Wooller ◽  
R. D. Wooller
Keyword(s):  
Seed Production ◽  
Inbreeding Depression ◽  
Western Australia ◽  
Fruit Set ◽  
Mating Strategy ◽  
South Coast ◽  
Mixed Mating ◽  
The South ◽  
Self Pollination ◽  
Mixed Mating Strategy

Differential exclusion of vertebrates and invertebrates from the inflorescences of Banksia media R.Br. on the south coast of Western Australia showed the species to be partially self-compatible. Access by invertebrates increased fruit set and additional access by vertebrates resulted in even greater fruit set. Honeyeater birds and marsupial nectarivores were abundant and widespread in the study area and most carried the pollen of Banksia media while it flowered. However, although B. media had the floral characteristics attributed to vertebrate pollination, self-pollination and pollination by insects clearly also play major roles in seed production. Banksia media regenerates solely from seed released after fire and we suggest that its mixed mating strategy is a compromise between inbreeding depression and risk of elimination from areas prone to occasional fires.

scholarly journals Breeding system and inbreeding depression in the rare orchid, Platanthera praeclara, in a fragmented grassland landscape

Botany ◽  
2018 ◽  
Vol 96 (3) ◽  
pp. 151-159 ◽  
Author(s):  
Steven E. Travers ◽  
Kirk Anderson ◽  
Pati Vitt ◽  
Marion O. Harris
Keyword(s):  
Inbreeding Depression ◽  
Seed Quality ◽  
Detectable Effect ◽  
Plant Fitness ◽  
Cross Pollination ◽  
Self Pollination ◽  
Capsule Production ◽  
Hand Pollination ◽  
Platanthera Praeclara ◽  
Self Compatibility

An important consequence of self-compatibility in plants is that self-pollination can have deleterious effects on plant fitness because of inbreeding. We conducted a hand pollination experiment under field conditions to measure the magnitude of inbreeding depression associated with self-pollination in the rare western prairie fringed-orchid Platanthera praeclara Sheviak and Bowles. By comparing capsules and seeds resulting from cross versus self-pollination treatments, we determined that self-pollination reduces seed quality while having no detectable effect on capsule production or seed numbers. A smaller percentage of seeds resulting from self-pollination contained an embryo (18%) relative to seeds from cross-pollination (46%). Seeds that had an embryo were scored for the size of the embryo, small or large. A smaller proportion of seeds from self-pollination contained a large embryo (75%) relative to seeds from cross-pollination (92%). These results suggest that sexual reproduction and recruitment in this rare plant are dependent on the frequency of pollinator visitations that result in outcrossing.

scholarly journals Inbreeding and Gene Action in Butternut Squash (Cucurbita moschata) Seed Starch Content

2014 ◽  
Vol 67 (1) ◽  
pp. 7169-7175 ◽  
Author(s):  
Sanin Ortiz Grisales ◽  
Lucy Viviana Bastidas Burbano ◽  
Ginna Alejandra Ordoñez Narváez ◽  
Magda Piedad Valdés Restrepo ◽  
Diosdado Baena García ◽  
...  
Keyword(s):  
Seed Production ◽  
Inbreeding Depression ◽  
Recurrent Selection ◽  
Gene Action ◽  
Starch Content ◽  
Inbred Lines ◽  
Cucurbita Moschata ◽  
Additive Type ◽  
Type Gene ◽  
Valle Del Cauca

The effect of inbreeding and gene action on butternut squash (Cucurbita moschata Duch.) seed production and seed starch content was evaluated at two locations in the department of Valle del Cauca, Colombia, using six accessions (S0) and their inbred lines S1 and S2. Significant differences were found between the accessions and inbred lines, but not between localities. The seed production and seed starch content showed no significant effects of inbreeding depression. An additive-type gene action predominated, suggesting that recurrent selection could be the best strategy to increase the frequencies of genes promoting seed production and seed starch content.

Effect of method and time of application of nitrogen fertiliser on yield and quality of seed of creeping red fescue

2000 ◽  
Vol 80 (4) ◽  
pp. 809-811 ◽  
Author(s):  
N. A. Fairey ◽  
L. P. Lefkovitch
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Seed Quality ◽  
Early Spring ◽  
Festuca Rubra ◽  
Grass Seed ◽  
Red Fescue ◽  
Time Of Application ◽  
Vigorous Plant ◽  
Tiller Density

Six trials were conducted on commercial seed fields of creeping red fescue (Festuca rubra L. var. rubra) in the Peace region to evaluate the sensitivity of seed production to the method and time of application of N fertiliser. In each trial, 68 kg ha−1 N was applied using three methods (surface-broadcast, granular, ammonium nitrate 34-0-0; foliar/soil spray of 28-0-0 solution N; soil-injected 28-0-0 solution N) at each of three times (fall, early spring, late spring). No statistically significant (P = 0.05) interaction, or main effect, of method and time of N were revealed for seed yield, fertile tiller density or for several seed quality characteristics. Seed yield varied greatly among trials (142 to 1240 kg ha−1) and averaged 566 kg ha−1. The results indicate that there is considerable flexibility in the method and time of application of N fertiliser for seed production of creeping red fescue in the Peace region, provided it is applied before the commencement of vigorous plant growth in the spring. Key words: Creeping red fescue, Festuca rubra L., nitrogen fertility, grass seed production, grass seed quality

scholarly journals Effects of inbreeding on number of piglets born total, born alive and weaned in Austrian Large White and Landrace pigs

2009 ◽  
Vol 52 (1) ◽  
pp. 51-64 ◽  
Author(s):  
A. Köck ◽  
B. Fürst-Waltl ◽  
R. Baumung
Keyword(s):  
Inbreeding Depression ◽  
Reproductive Performance ◽  
Regression Models ◽  
Inbreeding Coefficient ◽  
Significant Positive Effect ◽  
Weaned Piglets ◽  
Large White ◽  
Inbreeding Coefficients ◽  
Negative Effect ◽  
Positive Effect

Abstract. In this study records of 58 925 litters of Austrian Large White and 17 846 litters of Austrian Landrace pigs were analysed. Regression models were used to determine the effects of litter, dam and sire inbreeding on total number of born, born alive and weaned piglets in Large White and Landrace. In both populations, litter and dam inbreeding showed a negative effect on all traits. Sire inbreeding had no effect in Large White, whereas a significant positive effect was observed in Landrace. On average, inbred sires with an inbreeding coefficient of 10 % had 0.45 more piglets born total and 0.43 more piglets born alive in comparison to non-inbred sires. In a further analysis the total inbreeding coefficients of the animals were divided into two parts: »new« and »old« inbreeding. »New« inbreeding was defined as the period of the first five generations. It was shown that the observed inbreeding effects were not only caused by recent inbreeding. Reproductive performance was also affected by »old« inbreeding. Finally partial inbreeding coefficients of four important ancestors in each population were calculated to investigate if inbreeding effects are similar among these ancestors. The results revealed a varation of inbreeding effects among the four ancestors. Alleles contibuting to inbreeding depression were descendent from specific ancestors.

Preharvest glyphosate in alfalfa for seed production: Effect on alfalfa seed yield and quality

2003 ◽  
Vol 83 (1) ◽  
pp. 189-197 ◽  
Author(s):  
W. E. May ◽  
H. A. Loeppky ◽  
D. C. Murrell ◽  
C. D. Myhre ◽  
J. J. Soroka
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Seed Quality ◽  
Seedling Emergence ◽  
Canada Thistle ◽  
Seedling Vigour ◽  
Yield And Quality ◽  
Alfalfa Seed ◽  
Medicago Sativa L ◽  
Seed Yields

Preharvest applications of glyphosate have been shown to be effective in controlling Canada thistle in annual crops, but may reduce alfalfa seed yield depending on time and rate of application. The objective of this study was to determine the effect of preharvest applications of glyphosate on subsequent alfalfa seed yield and quality. The effects of timing, 1, 26, 51 and 76% alfalfa seed pod maturity, and rate, 0, 440, 880, 1320, and 1760 g a.i. ha-1, of a preharvest application of glyphosate on alfalfa seed yield and quality in the year of application, and regrowth and seed yield in the following year were determined. The rate of glyphosate applied did not affect seed yield in the application year; however, in the following year, growth and seed yield were reduced as rates increased. Delaying the application of glyphosate increased seed yields in the application year, but decreased alfalfa regrowth and flowering the following year. Germination and seedling emergence were not affected by the rate or timing of the glyphosate. A preharvest application of glyphosate at 1760 g a.i. ha-1 at 76% pod maturity is a viable option in the last year of seed production. Key words: Alfalfa (Medicago sativa L.), glyphosate, abnormal seeds, seed quality, and seedling vigour

Calcium Effects on Soybean Seed Production, Elemental Concentration, and Seed Quality

Crop Science ◽  
2000 ◽  
Vol 40 (2) ◽  
pp. 476-482 ◽  
Author(s):  
M.G. Burton ◽  
M.J. Lauer ◽  
M.B. McDonald
Keyword(s):  
Seed Production ◽  
Elemental Concentration ◽  
Seed Quality ◽  
Soybean Seed ◽  
Calcium Effects
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