The rate of preimaginal development of the blowfly, Calliphora vicina R.-D. (Diptera, Calliphoridae) under field and laboratory conditions

Vigor of soybean [Glycine max (L.) Merrill] seeds can be evaluated by measuring the electrical conductivity (EC) of the seed soaking solution, which has shown a satisfactory relationship with field seedling emergence, but has not had aproper definition of range yet. This work studies the relationship between EC and soybean seedling emergence both in the field and laboratory conditions, using twenty two seed lots. Seed water content, standard germination and vigor (EC, accelerated aging and cold tests) were evaluated under laboratory conditions using -0.03; -0.20; -0.40 and -0.60 MPa matric potentials, and field seedling emergence was also observed. There was direct relationship between EC and field seedling emergence (FE). Under laboratory conditions, a decreasing relationship was found between EC and FE as water content in the substrate decreased. Relationships between these two parameters were also found when -0.03; -0.20 and -0.40 MPa matric potentials were used. EC tests can be used successfully to evaluate soybean seed vigor and identify lots with higher or lower field emergence potential.

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Selección para calidad fisiológica de la semilla y rendimiento en líneas S2 derivadas de cuatro poblaciones tropicales de maíz (Zea mays L.)

Agronomía Mesoamericana ◽

10.15517/am.v7i1.24790 ◽

2016 ◽

Vol 7 (1) ◽

pp. 58

Author(s):

Enrique Navarro ◽

Cristina Vega ◽

Fernando Narváez ◽

Hugo Córdova

Keyword(s):

Genetic Variability ◽

Grain Yield ◽

Recurrent Selection ◽

Zea Mays L ◽

Agronomic Traits ◽

Reciprocal Recurrent Selection ◽

Laboratory Conditions ◽

Flower Plant ◽

Ear Height ◽

Field And Laboratory Conditions

This study was carried out in 1993 to evaluate S2 lines from four maize tropical populations improved by reciprocal recurrent selection. These lines were evaluated under field and laboratory conditions, the latter one to determine physiology quality. The main goal was to measure genetic variability within and among populations for traits such as grain yield, vigor and germination and to select the best lines under field and laboratory conditions. The combined analysis of variance showed great genetic variability among the S2 lines within and among populations for grain yield, days to flower, plant and ear height, among others. The maximum genetic variability was observed on the lines from population 43 and pool 23 for most of the traits, although the latter showed a greater genetic variability for grain yield. Besides, it is important to mention that the above populations included the best genotypes for grain yield, germination and vigor. Taking into account the above mentionel agronomic traits, fifteen lines were selected; 2 belong to population 43* pool 20, 2 from pool 19* pool 23, 8 from population 43, and 3 from pool 23. These results confirm the genetic superiority of the lines from populations 43 and pool 23, so that these populations should be recommended for future genetic improvement by reciprocal recurrent procedures.

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Annual dormancy cycles in Lesquerella fendleri (Brassicaceae) seeds stored under both field and laboratory conditions

Canadian Journal of Botany ◽

10.1139/b99-142 ◽

2000 ◽

Vol 77 (11) ◽

pp. 1648-1654

Author(s):

Laura A Hyatt ◽

Ann S Evans ◽

Carol C Baskin

Keyword(s):

Seed Storage ◽

Storage Conditions ◽

Perennial Species ◽

Lesquerella Fendleri ◽

Laboratory Conditions ◽

Fluctuating Environments ◽

Growth Chambers ◽

Field And Laboratory Conditions ◽

Dormancy Cycles ◽

Over Time

Patterns of germination over time were investigated in a short-lived desert perennial species, Lesquerella fendleri (Gray) S. Wats. Field-collected seeds were either buried in the field in cloth bags or stored in a glass jar under laboratory conditions. Regular germination tests were conducted under a range of alternating temperatures (buried seeds) or under differing water regimes (laboratory-stored seeds). Testing revealed Lesquerella fendleri to have an annual dormancy-nondormancy cycle, which was manifest regardless of seed storage conditions, suggesting that cycles may be partially endogenously regulated. Increasing seed germinability in field-stored seeds (maximum of 30% in year 1 and 95% in year 2) leads to the formation of a seed bank for at least 1 year and enhances the possibility of spreading germination events through time. This allows parent plants to maximize fitness in randomly fluctuating environments. The existence of two seedling flushes in the field and single germinability peaks in growth chambers suggests that dormancy cycling may support the formation of a metapopulation with subpopulations which are, although physically intermingled, genetically distinct.

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The Mobility of Hydrocarbons at Unsaturated Water Conductivity Under Field and Laboratory Conditions

Soil & Environment - Contaminated Soil ’95 ◽

10.1007/978-94-011-0415-9_87 ◽

1995 ◽

pp. 369-370

Author(s):

I. Drachenberg ◽

D. Goetz

Keyword(s):

Water Conductivity ◽

Laboratory Conditions ◽

Field And Laboratory Conditions

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Applied Zoology for Forming of Research Competence at Students of Biologists

Advances in Educational Technologies and Instructional Design - Handbook of Research on Students' Research Competence in Modern Educational Contexts ◽

10.4018/978-1-5225-3485-3.ch017 ◽

2018 ◽

pp. 321-341

Author(s):

Farit Miniyarov

Keyword(s):

Research Work ◽

Rating System ◽

Research Projects ◽

Research Activity ◽

Research Competence ◽

Laboratory Conditions ◽

Uniform Approach ◽

System A ◽

Field And Laboratory Conditions

This chapter about how to involve students of biologists in research work, using benefits of applied zoology. The first part of the chapter provides the overview of such questions as research activity of students, methods and conditions of its forming, feature for students of biologists. The second part is devoted to the step-by-step organization of research activity according to levels of readiness of students. Much attention in this part is paid to questions of applied zoology: directions and objects of researches; structure and content of laboratory works, scientific and practical and research projects; uniform approach to use of techniques of researches in field and laboratory conditions. For assessment of results of researches and formation of research competence of students such methods as rating system, a portfolio, methods of expert estimates are offered.

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Effects of Age, Burial, and Region on Germination and Viability of Halogeton Seed

Weed Science ◽

10.1017/s0043174500030915 ◽

1969 ◽

Vol 17 (1) ◽

pp. 63-65 ◽

Cited By ~ 11

Author(s):

W. C. Robocker ◽

M. C. Williams ◽

R. A. Evans ◽

P. J. Torell

Keyword(s):

Seed Germination ◽

Soil Surface ◽

First Year ◽

Laboratory Conditions ◽

Winter Conditions ◽

Field Germination ◽

Field And Laboratory Conditions ◽

Halogeton Glomeratus

The longevity of brown and black forms of seed of halogeton (Halogeton glomeratus (M. Bieb.) C. A. Mey.), buried at four depths, was determined for a 10-year period in Nevada, Idaho, Utah, and Washington. The black form of seed had almost 100% field germination at all depths by the end of the first year and had completely germinated or was nonviable by the end of the second. Brown seed on the soil surface began field germination the first year at all locations and had germinated or become nonviable at the end of 6 years. Burial at 1, 3, and 6 inches delayed the peak of viability and tended to increase longevity of brown seed. Germination was less than 0.5% at the end of 10 years, and viability was near zero under both field and laboratory conditions. Seed germinated and lost viability most rapidly in Washington, the location where most favorable winter conditions for germination occurred.

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