Culling phenotypically inferior trees in seed production area enhances seed and seedling quality of Acacia auriculiformis

2011 ◽  
Vol 22 (1) ◽  
pp. 21-26 ◽  
Author(s):  
V. Sivakuma ◽  
B. Gurudevsingh ◽  
R. Anandalakshmi ◽  
R. R. Warrier ◽  
S. Sekaran ◽  
...  
Keyword(s):  
Seed Production ◽  
Seedling Quality ◽  
Acacia Auriculiformis ◽  
Production Area

Mating system of Racosperma auriculiforme in a seed production area in Zaire

1993 ◽  
Vol 71 (6) ◽  
pp. 779-785 ◽  
Author(s):  
P. Damase Khasa ◽  
William M. Cheliak ◽  
Jean Bousquet
Keyword(s):  
Mating System ◽  
Seed Production ◽  
Random Mating ◽  
Single Locus ◽  
Acacia Auriculiformis ◽  
Mixed Mating ◽  
Outcrossing Rates ◽  
Production Area ◽  
Mixed Mating Model ◽  
Mating Model

Analysis of the mating system of Racosperma auriculiforme (formerly Acacia auriculiformis) in a seed production area in Zaire was conducted using a mixed mating model at five polymorphic loci (Est-2, Est-3, G6p-dh, Nadhdh-2, Pgm-1). Single-locus estimates of outcrossing rate varied widely between 0.615 and 1.204 and were significantly heterogenous among and within the stands. Weighted means of single-locus estimates of outcrossing rates (ts) ranged from 0.859 to 1.032 while multilocus estimates of outcrossing rates (tm) ranged from 0.863 to 1.059. Comparisons between the single-locus estimates and the multilocus estimates of outcrossing rates indicated that most of the inbreeding detected was due to consanguineous (sibling) matings rather than selfing. Comparisons of observed and expected inbreeding coefficients indicated a general deficit of heterozygotes over the frequencies expected from random mating in the single stands and the pooled stands. Locus to locus variation in outcrossing rates suggested that violation of the mixed mating model might have occurred. Implications for seed production, collection, and distribution for reforestation are discussed. Key words: Acacia, mating system, Racosperma, seed production area, Zaire.

Importance of diseases in herbage seed production

1980 ◽  
Vol 1 ◽  
pp. 36-40
Author(s):  
G.C.M. Latch
Keyword(s):  
Seed Production ◽  
Control Measures ◽  
Puccinia Graminis ◽  
Minor Importance ◽  
Farming Practices ◽  
Head Smut ◽  
Yield And Quality ◽  
Suggested Keywords ◽  
Production Diseases

Yield and quality of herbage seed can be affected by many diseases. In New Zealand the most important diseases of grasses are rusts, especially stem rust on ryegrasses, cocksfoot and timothy; head smut of bromes; and ergot of paspalum. Blind-seed disease is of minor importance on ryegrass at present. Clover yield can be affected by rot, scorch and stem nematode. These diseases and others are discussed in relation to changing farming practices, and disease control measures are suggested. Keywords: Herbage seed production, diseases, Puccinia graminis, Ustilago bullata, Claviceps paspali, Gloeotinia temulenta

scholarly journals Seed production of lemon balm and the quality of its seeds in the middle of the Volga region

2019 ◽  
pp. 34-36
Author(s):  
Ilya Alexandrovich Khapugin
Keyword(s):  
Seed Production ◽  
Weather Conditions ◽  
Mineral Fertilizers ◽  
Small Scale ◽  
Melissa Officinalis ◽  
Seed Productivity ◽  
Lemon Balm ◽  
Maximum Productivity ◽  
Scale Experiment

The influence of mineral fertilizers on seed productivity and quality of obtained seeds of lemon balm (Melissa officinalis L.) was studied in the field small-scale experiment under conditions of unstable moistening of the Mordovia Republic. As a result, it was found that seed productivity varied depending on weather conditions and the types of fertilizers introduced. It was shown that the maximum productivity of Melissa officinalis plants was on the variant with the use of phosphorus-potassium fertilizers at a dose of P60K90 (71.2±78.5 g/m2 in 2017 and 48.8±4.3 g/m2 in 2018), while it exceeded the control variant by 74-91 %. The total germination of seeds of Melissa officinalis practically did not change over the years, and was in the range of 37-39 %. Separation of seeds according to the degree of aging allowed to increase germination 11.4-13.3 %.  

scholarly journals Reduction of Ryegrass (Lolium multiflorum Lam.) Natural Re-Sowing with Herbicides and Plant Growth Regulators

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1960
Author(s):  
Afonso Henrique Schaeffer ◽  
Otávio Augusto Schaeffer ◽  
Diógenes Cecchin Silveira ◽  
João Arthur Guareschi Bertol ◽  
Debora Kelli Rocha ◽  
...  
Keyword(s):  
Plant Growth ◽  
Plant Growth Regulators ◽  
Seed Production ◽  
Growth Regulators ◽  
Fruit Development ◽  
Lolium Multiflorum ◽  
Development Stage ◽  
Ammonium Glufosinate ◽  
Physiological Quality

Ryegrass (Lolium multiflorum Lam.) is the main winter weed of crops in Southern Brazil. High competitiveness, adaptability, widespread resistance to herbicides and seed dormancy make the plant a permanent problem. Herbicides, as well as plant growth regulators, can be used as a management option for ryegrass seed production, however there is no consensus among authors at which stage of the plant the application is most effective. Thus, this study aimed to evaluate the production and physiological quality of ryegrass seeds in response to the application of herbicides and plant growth regulators in three stages of plant development (inflorescence emergence, flowering and fruit development). Each treatment consisted of applying two different doses of each of the active ingredients: ammonium glufosinate, clethodim, glyphosate, iodosulfuron-methyl, paraquat and 2,4-D (herbicides); ethephon and trinexapac-ethyl (plant growth regulators), still an untreated control, totaling 17 treatments for each stage of development. The experimental design used was randomized blocks, with three replications. The variables evaluated were: seed production (kg ha−1), thousand seed weight (g), viability (%), germination (%), first germination count (%), dormant seeds (%) and dead seeds (%). The ryegrass seed production reduced 100% with clethodim, glyphosate, ammonium glufosinate or paraquat applied in the inflorescence emergence or flowering stages. In the fruit development stage, all treatments (herbicides and plant growth regulators) caused deleterious effects on seed production, the greatest effect occurred with paraquat (95%). Paraquat, ammonium glufosinate and clethodim affected the physiological quality of the seeds when applied in fruit development stage. This research demonstrated that the application of herbicides in the ryegrass reproductive stage decreases its seedbank replenishment (natural re-sowing), with the potential to harm its progeny.

scholarly journals Quantitative Determination and Sampling of Lamivudine and Zidovudine Residues for Cleaning Validation in a Production Area

2007 ◽  
Vol 90 (3) ◽  
pp. 715-719 ◽  
Author(s):  
Maria InÊs Rocha Miritello Santoro ◽  
Tatiana Tatit Fazio ◽  
Anil Kumar Singh ◽  
Erica Rosa Maria Kedor-Hackmann
Keyword(s):  
Chromatography Method ◽  
Drug Products ◽  
Cleaning Validation ◽  
Relative Standard ◽  
Immunodeficiency Virus ◽  
Production Area ◽  
The Mean ◽  
Liquid Chromatography Method ◽  
Carry Over

Abstract Lamivudine (3TC) and zidovudine (AZT) are systemic antiviral substances extensively used in human immunodeficiency virus (HIV) infected patients. Nowadays, 3TC, AZT, and several other pharmacologically potent pharmaceuticals are manufactured in the same production area. To assure quality of drug products and patient safety, properly validated cleaning methodology is necessary. A carefully designed cleaning validation and its evaluation can ensure that residues of 3TC and AZT will not carry over and cross contaminate the subsequent product. The aim of this study was to validate a simple analytical method for verification of residual 3TC and AZT in equipment used in the production area and to confirm the efficiency of the cleaning procedure. The liquid chromatography method was validated using a Nova-Pak<sup/> C18 column (3.9 150 mm, 4 m particle size) and methanolwater (20 + 80, v/v) as the mobile phase at a flow rate of 1.0 mL/min. Ultraviolet detection was made at 266 nm. The calibration curve was linear over a concentration range of 2.022.0 g/mL with a correlation coefficient of 0.9998. The detection and quantitation limits were 0.36 and 1.21 g/mL, respectively. The intra-day and interday precision expressed as relative standard deviation were below 2.0%. The mean recovery of the method was 99.19%. The mean extraction recovery from manufacturing equipment was 83.5%.

CONSUMPTION OF VARIOUS DOUGLAS-FIR CONE STRUCTURES BY BARBARA COLFAXIANA (LEPIDOPTERA: OLETHREUTIDAE)

1977 ◽  
Vol 109 (9) ◽  
pp. 1293-1294
Author(s):  
T. Evan Nebeker
Keyword(s):  
Energy Transfer ◽  
Seed Production ◽  
Energy Budget ◽  
Forest Ecosystem ◽  
Larval Stage ◽  
Douglas Fir ◽  
National Forest ◽  
Larval Instars ◽  
Production Area

During 1971 a study was conducted to determine the amount of the various Douglasfir cone structures (bracts, scales, and seeds) consumed by the Douglas-fir cone moth, Barbara colfaxiana (Kft.), in the Buckhead Seed Production Area, Willamette National Forest, Oregon. It was not the intent of this study to develop a complete energy budget for B. colfaxiana, but rather to determine the number of calories consumed, on the average, by an individual during the larval stage. The behavior of the various larval instars has been discussed by Radcliffe (1952), Keen (1958), Hedlin (1960), and Nebeker (1977). The calorie was selected as the unit of measure due to its usefulness in modeling energy transfer from one component to another in the forest ecosystem.

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