Results 51 to 60 of about 79,061 (307)
American Journal of Agricultural Economics, EarlyView.Abstract While multiple factors explain low adoption rates of improved varieties by small‐scale farmers in sub‐Saharan Africa, a key supply‐side constraint is the limited availability of seed embodying new traits in the volume, quality, price, and timeliness required by farmers. This constraint is partly attributable to classical failures in the market
Dawit Mekonnen +5 more
wiley +1 more source
Panicle inclination influences pollination stability of rice (Oryza sativa L.)
Plant Production Science, 2020 Rice pollination occurs when pollen grains fall by gravity from the anther onto the stigma and has been thought to be assured under suitable conditions. However, the position of the stigma relative to the anther pores may affect pollination.
Aung Win +2 more
doaj +1 more source
Morphology and tructure of the pollen cone and pollen grain of the Araucaria species from Argentina [PDF]
, 2008 The pollen cone and the pollen grain of the two Argentinean species of Araucaria are described with LM, SEM and TEM. Primordia of pollen cones are formed in April and May and reach maturity by mid-October in A. angustifolia (Bert.) O.
Caccavari, Marta Alicia +2 more
core
American Journal of Botany, EarlyView.Abstract Premise We examined the African arid corridor (AAC) disjunction pattern of vascular plants between northeastern and southwestern Africa in the context of geological and climatic events since the late Miocene. We developed a phylogenetic and biogeographical framework for the arid‐adapted genus Sesamothamnus (Pedaliaceae), a classic example of ...
John G. Zaborsky +6 more
wiley +1 more source
Fullerene fine particles adhere to pollen grains and affect their autofluorescence and germination
Nanotechnology, Science and Applications, 2011 Hideki Aoyagi, Charles U UgwuLife Science and Bioengineering, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, JapanAbstract: Adhesion of commercially produced fullerene fine particles to Cryptomeria japonica ...
Aoyagi H, Ugwu CU
doaj
Morphological differentiation of Primula veris L. pollen from natural and cultivated populations
Acta Societatis Botanicorum Poloniae, 2011 Micromorphological characterisation and the comparative statistical analysis of the size of Primula veris L. pollen grains collected in three natural and three cultivated populations were done. Observations were carried out with SEM.
Maria Morozowska, Krystyna Idzikowska
doaj +1 more source
The Anatomical Record, EarlyView.Abstract Teleocichla comprises small cichlids that inhabit the rapid streams of Amazonian rivers; however, there has been limited research on their encephalon morphology. This study examined the neuroanatomy of four species, focusing on volumetric measurements of their encephalon subregions, and providing a histological description of the encephalon of
Renan Leão‐Reis +4 more
wiley +1 more source
Callose (β-1,3 glucan) is essential for Arabidopsis pollen wall patterning, but not tube growth [PDF]
, 2005 Background: Callose (β-1,3 glucan) separates developing pollen grains, preventing their underlying walls (exine) from fusing. The pollen tubes that transport sperm to female gametes also contain callose, both in their walls as well as in the plugs that ...
Swanson, Rob
core +2 more sources
High-resolution palynological analysis in Lake Sapanca as a tool to detect recent earthquakes on the North Anatolian Fault [PDF]
, 2009 High-resolution palynological analysis of a 38-cm-long core collected from Lake Sapanca, northwest Turkey, reveals large earthquakes that occurred during the second half of the 20th century along the North Anatolian Fault Zone. Four events have disturbed
Boyraz, S, Gürbüz, A, Leroy, SAG
core +1 more source
Early evolutionary history of the seed
Biological Reviews, EarlyView.ABSTRACT The seed is an essential stage in the life history of gymnospermous and angiospermous plants, facilitating both their survival and dispersal. We reappraise knowledge of the evolutionary history of the gymnospermous seed, from its origin in the late Devonian through to the well‐known end‐Permian extinctions – an interval encompassing the ...
Richard M. Bateman +2 more
wiley +1 more source