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Cytological Observations in Coffea. VI. Embryo and Endosperm Development in Coffea arabica L
... The outer cover of the seed is formed by a hard pale brown endocarp that becomes the "parchment" after drying. The endocarp contains an enclosed seed, which has a thin, green testa known as the spermoderm or "silver skin" (figure 1), which is a remnant of the perisperm (Mendes, 1941). ...
... Measurements made with a large number of seeds of Coffea arabica indicate that the seeds are 10 to 18 mm long and 6.5 to 9.5 mm wide (Dedecca, 1957); C. canephora seed 5.62 to 7.44 mm wide. Other species such as C. racemosa have smaller seeds (5-7 mm long and 3-3.5 mm wide (Guerreiro Filho, 1992) (figure 2).The endosperm, which is a living tissue, contains a hard external region and soft internal region, which surround the embryo (Krug and Carvalho, 1939;Mendes, 1941;Dedecca, 1957;De Castro and Marraccini, 2006). The part of the endosperm in front of the radicle tip is referred to as endosperm cap or micropylar endosperm and around the rest of the embryo is the lateral endosperm (Silva et al., 2004) (figure 1). ...
... The embryo contains few storage reserves, and depends upon the endosperm for nutrients until the seedling become autotrophic (Giorgini and Campos, 1992). Polyembryony and empty seeds have been observed in coffee at a frequency of 1.2 % (Mendes, 1941). Thus, using coffee seed having endosperm quality (healthy) and better seed size with enough endosperm play vital contribution for seedling growth up to it independently prepare its own food and in growing productive coffee plant. ...
Coffea arabica is angiosperm plant and propagates by seed like other coffea species. Limited quality coffee seed production and supplying system is currently challenging issue. Thus, the present review conducted with the intension of factors affecting quality coffee seed production and its supplying system in Ethiopia. The two principal factors that affect quality coffee seed production are pre-harvest and post-harvest factors. Pre-harvest factor include field management practice, insect pest and disease and stage of fruit maturity; while seed drying method, seed storage time, seed initial moisture content and types of container for seed storage are post harvest factors. Deep reddening and reddening stage fruit used for seed showed more than 88% germination; but at yellow and green stage germination was 70% and less. Seed drying under corrugated iron and glass tukul enhanced germination up to 80% and more; but under open sun it ceased to 70%. Seedling emergence percentage rapidly decreased after 3-5 months of storage time; hence, seed sowing to nursery as soon as harvesting without further storage increase seedling emergence and make earlier the attain first true leaf and mean day of germination. Seed with initial moisture content of 55.2% stored in glass jar recorded 97.5%, 89.1%, and 84.5% in seed viability; seedling emergence percentage and seedling attain first true leaf respectively after 5 months storage. Jimma Agricultural Research Center (JARC) has released 42 improved coffee varieties up date, and distributed 341.821 ton and 347,308 coffee seed and seedling respectively. However, seed demand and supply is not compatible as a result of seed supply system problems in Ethiopia. Formal coffee seed supply system mandate given to JARC, and well established informal coffee seed supply system is lacking in Ethiopia. Thus, for further technology disseminate and to response seed demand, formal and informal coffee seed supply need to be diversified with strong agricultural extension work in Ethiopia.
... The outer cover of the seed is formed by a hard pale brown endocarp that becomes the "parchment" after drying. The endocarp contains an enclosed seed, which has a thin, green testa known as the spermoderm or "silver skin" (figure 1), which is a remnant of the perisperm (Mendes, 1941). ...
... Measurements made with a large number of seeds of Coffea arabica indicate that the seeds are 10 to 18 mm long and 6.5 to 9.5 mm wide (Dedecca, 1957); C. canephora seed 5.62 to 7.44 mm wide. Other species such as C. racemosa have smaller seeds (5-7 mm long and 3-3.5 mm wide (Guerreiro Filho, 1992) (figure 2).The endosperm, which is a living tissue, contains a hard external region and soft internal region, which surround the embryo (Krug and Carvalho, 1939;Mendes, 1941;Dedecca, 1957;De Castro and Marraccini, 2006). The part of the endosperm in front of the radicle tip is referred to as endosperm cap or micropylar endosperm and around the rest of the embryo is the lateral endosperm (Silva et al., 2004) (figure 1). ...
... The embryo contains few storage reserves, and depends upon the endosperm for nutrients until the seedling become autotrophic (Giorgini and Campos, 1992). Polyembryony and empty seeds have been observed in coffee at a frequency of 1.2 % (Mendes, 1941). Thus, using coffee seed having endosperm quality (healthy) and better seed size with enough endosperm play vital contribution for seedling growth up to it independently prepare its own food and in growing productive coffee plant. ...
... The outer cover of the seed is formed by a hard pale brown endocarp that becomes the "parchment" after drying. The endocarp contains an enclosed seed, which has a thin, green testa known as the spermoderm or "silver skin" (figure 1), which is a remnant of the perisperm (Mendes, 1941). ...
... Measurements made with a large number of seeds of Coffea arabica indicate that the seeds are 10 to 18 mm long and 6.5 to 9.5 mm wide (Dedecca, 1957); C. canephora seed 5.62 to 7.44 mm wide. Other species such as C. racemosa have smaller seeds (5-7 mm long and 3-3.5 mm wide (Guerreiro Filho, 1992) (figure 2).The endosperm, which is a living tissue, contains a hard external region and soft internal region, which surround the embryo (Krug and Carvalho, 1939;Mendes, 1941;Dedecca, 1957;De Castro and Marraccini, 2006). The part of the endosperm in front of the radicle tip is referred to as endosperm cap or micropylar endosperm and around the rest of the embryo is the lateral endosperm (Silva et al., 2004) (figure 1). ...
... The embryo contains few storage reserves, and depends upon the endosperm for nutrients until the seedling become autotrophic (Giorgini and Campos, 1992). Polyembryony and empty seeds have been observed in coffee at a frequency of 1.2 % (Mendes, 1941). Thus, using coffee seed having endosperm quality (healthy) and better seed size with enough endosperm play vital contribution for seedling growth up to it independently prepare its own food and in growing productive coffee plant. ...
... Il arrive cependant des cas de polyspermie. De même, des ovaires triloculés sont présents chez certaines espèces comme C. heterocalyx et C. arabica (Chevalier, 1947 ;Dedecca, 1957 ;Mendes, 1941 ;Vishveshwara & Chinnappa, 1965). La fécondation des deux ovules conduit à des fruits contenant deux graines. ...
... Le devenir de cette dernière zone est sujet à controverse. En effet, certains auteurs considèrent que ce tissu est composé d'une seule couche de cellules quadrangulaires qui disparait dans les fruits matures (Chevalier, 1947) ; pour d'autres l'endocarpe est constitué de plusieurs couches de cellules et devient ensuite la parche (De Castro & Marraccini, 2006 ;De Toledo, 1961 ;Dedecca, 1957 ;Mendes, 1941 ;Vishweswara & Chinnappa, 1965). ...
... Cinq à six semaines après la floraison les premières divisions de l'endosperme apparaissent et il devient visible au moins à partir de 12 semaines après floraison (SAF) (Vishveshwara & Chinnappa, 1965). A partir de là, l'endosperme, qui est un tissu triploïde d'origine nonsporophytique (Mendes, 1941 ;Medina, 1964Medina, , 1965De Castro et al., 2001), se développe et remplace progressivement de périsperme. A la fin de la croissance, l'endosperme occupe la totalité de la loge et le périsperme forme une fine pellicule argentée de 70µm entourant l'albumen (De Castro et al., 2001 ;Dedecca, 1957 ;Mendes, 1941). ...
Coffea arabica var Laurina (Bourbon pointu, BP), is a natural mutant of C. arabica ‘Bourbon’ (B). The laurina mutation is recessive, monolocus and Mendelian, with pleiotropic effects. This work highlighted new effects of this mutation, with histological, morphological and biochemical approaches on seeds development and on seedlings. Simultaneous fitting of growth curves of B and BP and their standardization allow comparisons of these varieties and fine study of polysaccharide cell wall (PCW) composition over time. Thus, anatomic specificities, development stages (st) and fruit age were linked (growth: st 1-2 to 4; maturation: st 5 to 7). When taking in account the CWP evolution in time-course, three phases occurred: φ 1 (st 1-2, 3), φ 2 (st 3, 4 and the beginning of 5), and φ 3 (the end of 5, st 6, 7). The two first were affected by the mutation probably through maternal effect (perisperm). In seedlings, the hypocotyls semi-dwarfism in light growth condition is an effect of the mutation and was due to a lower cell number than in B. The phytohormones content was also affected (ABA, auxine, cytokinins). But, neither CWP composition nor chlorogenics acids (CQA) content were affected by the mutation, or growth condition (expected for CQA content in roots). The composition in CWP and CQA was different depending on organs. Finally, caffeine (CAF) content was affected by the mutation in light or darkness conditions. These results represent an important step in 1/ the characterization of the pleiotropic effects of the laurina mutation, 2/ the understanding of the CWP evolution in seed time course, and 3/ new knowledge on seedlings (hormone, CAF, CQA and CWP composition).
... Questo lavoro mirato allo studio dello sviluppo del seme di Coffea arabica, avvalendosi di differenti tecniche microscopiche, ha cercato di dare un contributo agli studi effettuati precedentemente da Houk (1938), Mendes (1941), Dedecca (1957), Wormer (1966), Dentan (1977 e De Castro (2002Castro ( , 2005 Per prima cosa è stata effettuata l'analisi dimensionale delle drupe su un pool di campioni scelto casualmente tra quelli arrivati in laboratorio usando un calibro digitale lungo tre linee di misura: lunghezza, asse maggiore e asse minore in millimetri, sia per le drupe che per i semi. I campioni selezionati sono stati inclusi in resina Technovit 7100 (dall'inizio della fioritura fino alla 20 a settimana AA) e tagliati con un microtomo rotativo (sezioni da 6 µm). ...
... Secondo Leliveld (1938) la fecondazione del sacco embrionale in Coffea arabica dovrebbe avvenire da trenta a cinquanta ore dopo l'impollinazione, mentre secondo Mendes (1941) anche solo dopo dodici ore. In alcuni casi è possibile che il periodo di attesa tra impollinazione e fecondazione si protragga per qualche giorno. ...
... Il piccolo embrione si trova alla base del seme, nella parte convessa, dotato di ipocotile e cotiledoni cuoriformi; nelle prime fasi embrionali, lo zigote resta in un periodo di quiescenza di circa sessanta-settanta giorni, prima di accrescersi. L'endosperma può essere osservato nel seme intorno ai trenta giorni dopo la fecondazione del fiore (Mendes, 1941); nel seme maturo è un tessuto corneo, formato principalmente da cellule poliedriche. La fila di cellule più esterna, a contatto con la pellicola argentea, è più uniforme. ...
... The histological structure of the coffee bean was also studied from pollination up to maturation (Graner 1936(Graner , 1938Joshi 1938;Leliveld 1938;Fagerlind 1939;Mendes 1941;Chevalier 1947;Dedecca 1957;Vishveshwara and Chinnappa 1965). In C. arabica, the ovary is generally two or even rarely three loculed, 1 and each locule contains one anatropous ovule, although polyspermy sometimes occurs. ...
... For other authors, it would be formed by several layers at the origin of the parchment. (Mendes 1941;Dedecca 1957;Pia de Toledo 1961;Vishveshwara and Chinnappa 1965;De Castro et al. 2005). ...
... After this date, endosperm gradually replaces perisperm. At the end of growth, perisperm remains are located on the external part of the seed in the form of ''silver skin'', and the seeds are considered to be albuminous (Mendes 1941;Dedecca 1957;De Castro et al. 2001). The endosperm sometimes aborts, resulting in an empty locule (Sybenga 1961;Wormer 1966). ...
Key message
The comparison between the cultivar Bourbon and its mutant, the Bourbon pointu, of
Coffea arabica
led to five novel findings on fruit development and three main impacts of the mutation.
Abstract
Coffea arabica ‘Laurina’ (Bourbon pointu) is a natural mutant of Coffea arabica ‘Bourbon’. Relative to the ‘Bourbon’ cultivar, it is characterized by internode dwarfism, a Christmas tree shape, and lower caffeine content. The effects of the laurina mutation on fructification over time, the fruit structure and seed characteristics were studied here. Fruits of ‘Bourbon’ and ‘Bourbon pointu’ were monitored. The trees were grown in the same plot and flowered on the same day. Harvesting was done every 2 weeks from the 6th to the 26th week after flowering. Histological observations were carried out using multiphoton and conventional microscopes. The measurements concerned the fruit, parchment and seed. Five novel findings on fructification development were obtained: (1) a sigmoid model and non-linear regression efficiently described the phenomenon; (2) a precise relationship was defined between the qualitative stages of fructification and quantitative observations, thus revealing key weeks in this process; (3) the parchment had a mesocarpic origin; (4) a meristematic zone was present close to the parchment; and (5) an endocarp with three cell layers was visible in young fruits. Three effects of the laurina mutation were highlighted: (1) fruit growth ended 1 week earlier in ‘Bourbon’, but without difference in fruit length. In contrast, fruits were wider on average in ‘Bourbon’; (2) the parchment of narrow seeds in ‘Bourbon pointu’ was thicker than in other ‘Bourbon pointu’ and ‘Bourbon’ seeds; and (3) the narrow seed frequency in ‘Bourbon pointu’ depended on environmental conditions.
... The outer cover of the seed is formed by a hard pale brown endocarp that becomes the "parchment" after drying. The endocarp contains an enclosed seed, which has M.T.S. EIRA et al. a thin, green testa known as the spermoderm or "silver skin" (figure 1), which is a remnant of the perisperm (Mendes, 1941). In C. canephora seeds the spermoderm is adherent and brown (Fazuoli, 1986). ...
... The endosperm, which is a living tissue, contains a hard external region and soft internal region, which surround the embryo (Krug and Carvalho, 1939;Mendes, 1941;Dedecca, 1957;De Castro and Marraccini, 2005). The part of the endosperm in front of the radicle tip is referred to as endosperm cap or micropylar endosperm and around the rest of the embryo is the lateral endosperm (da Silva et al., 2004) (figure 1). ...
... The embryo contains few storage reserves, and depends upon the endosperm for nutrients until the seedling become autotrophic (Giorgini and Campos, 1992). Polyembryony and empty seeds have been observed in coffee at a frequency of 1.2 % (Mendes, 1941). ...
Coffee is a member of the Rubiaceae family and the genus Coffea. There are more than 70 species of coffee but only two are economically important: Coffea arabica L. and Coffea canephora Pierre; 70 % of the coffee traded in the world is arabica and 30 % is robusta (C. canephora). Other species such as C. congensis, C. dewevrei and C. racemosa have some interesting genetic characteristics, including resistance to pests and diseases and are used in breeding programs. To satisfy the demand for coffee within Brazil and around the world, intensive breeding programs have been undertaken to create new cultivars which are resistant to diseases and insects, and to incorporate new traits of value. In addition, new production and processing technologies are introduced every year, which have led to an enormous improvement in coffee production. Although progress has been made, not many studies have been devoted to the improvement of coffee seed quality for propagation. The purpose of this paper is to review our understanding of coffee seed physiology. Most of the work published in the literature and reported in this paper is on C. arabica seeds, although some aspects of C. canephora seed physiology are also included. Knowledge of seed physiology of other Coffea species is poor, with the exception of storage physiology, which is mostly related to germplasm conservation. Although this review will discuss some aspects of seed development and morphology, germination and storage physiology, the focus will be on germinability, and desiccation tolerance, with emphasis on the conservation of genetic resources
... The coffee (Coffea arabica L.) embryo is enveloped by an endosperm tissue (Krug and Carvalho 1939; Mendes 1941). The fully differentiated embryo lies inside an embryo cavity, is 3–4 mm long, and is composed of an axis and two cotyledons (Rena and Maestri 1986). ...
... The endosperm is surrounded by the endocarp, which resembles a seed coat (Chin and Roberts 1980). The coffee endosperm is composed of a hard greenish tissue with polyhedral cells, is isodiametrically divided into a hard external endosperm and a soft internal endosperm (Dedecca 1957), and belongs to the nuclear type (Mendes 1941). The endosperm cells have very thick walls that are crossed by plasmodesmata (Dentan 1985). ...
... celery (Jacobsen and Pressman 1979; van der Toorn and Karssen 1992). However, the mature coffee seed contains a fully differentiated mature embryo (Mendes 1941 ) but still displays growth before completion of germination. Valio (1976) proposed that ABA inhibits germination of the coffee seed through inhibition of embryo growth. ...
The mechanism and regulation of coffee seed germination were studied in Coffea arabica L. cv. Rubi. The coffee embryo grew inside the endosperm prior to radicle protrusion and abscisic acid (ABA) inhibited the increase in its pressure potential. There were two steps of endosperm cap weakening. An increase in cellulase activity coincided with the first step and an increase in endo-beta-mannanase (EBM) activity with the second step. ABA inhibited the second step of endosperm cap weakening, presumably by inhibiting the activities of at least two EBM isoforms and/or, indirectly, by inhibiting the pressure force of the radicle. The increase in the activities of EBM and cellulase coincided with the decrease in the force required to puncture the endosperm and with the appearance of porosity in the cell walls as observed by low-temperature scanning electronic microscopy. Tissue printing showed that EBM activity was spatially regulated in the endosperm. Activity was initiated in the endosperm cap whereas later during germination it could also be detected in the remainder of the endosperm. Tissue printing revealed that ABA inhibited most of the EBM activity in the endosperm cap, but not in the remainder of the endosperm. ABA did not inhibit cellulase activity. There was a transient rise in ABA content in the embryo during imbibition, which was likely to be responsible for slow germination, suggesting that endogenous ABA also may control embryo growth potential and the second step of endosperm cap weakening during coffee seed germination.
... La cubierta exterior de la semilla está formada por un endocarpio duro marrón claro que se convierte en el pergamino después del secado. El endocarpio contiene una semilla que posee una testa delgada y de color verde conocida como espermodermo o "piel plateada", que constituye el remanente del perispermo (Mendes, 1941). Las mediciones realizadas en un gran número de semillas de Coffea arabica indican que las semillas tienen de 10 a 18 mm de largo y de 6,5 a 9,5 mm de ancho (Dedecca 1957). ...
... Se han observado casos de poliembrionía y de semillas vacías con una frecuencia de 1,2%. (Mendes, 1941) En el café, la producción de semilla se caracteriza típicamente por una floración y desarrollo de frutos asincrónicos. En café Arábica, la antesis puede ocurrir en un solo día o durante varios días, con una o más floraciones en un solo periodo reproductivo (Wormer 1964, Alvim 1973. ...
... Below, is presented a schematic graph of tissue changes occurring during coffee fruit development. R.D. DE CASTRO and P. MARRACCINI the endosperm (figures 1and 2), sometimes referred to as the " silver skin " (Mendes, 1941Mendes, , 1942 Wormer, 1964 Wormer, , 1966 De Castro et al., 2001, 2005 Miriam et al., in this issue). The endosperm actually corresponds to the bean that, after the post-harvest treatments, will form the " green coffee " that is sold in the international markets. ...
... Leroy and C. Montagnon, personal communication). Endosperm: As in other plants, the endosperm of coffee is a triploid tissue with a non-sporophytic origin (Mendes, 1941, Medina, 1964, 1965, De Castro et al., 2001). Cytological observations carried out a few days after anthesis already allows its identification, as the embryo sac (se) (figure 2A). ...
In commercial coffee species (Coffea arabica and Coffea canephora), fruit development is a lengthy process, characterized by
tissue changes and evolutions. For example, soon after fecundation and up to mid development, the fruit is mainly constituted
of the pericarp and perisperm tissue. Thereafter, the perisperm gradually disappears and is progressively replaced by the
endosperm (true seed). Initially present in a “liquid” state, the endosperm hardens as it ripens during the maturation phase, as
a result of accumulation of storage proteins, sucrose and complex polysaccharides representing the main reserves of the seed.
The last step of maturation is characterized by the dehydration of the endosperm and the color change of the pericarp. Important
quantitative and qualitative changes accompany fruit growth, highlighting the importance of its study to better understand
the final characteristics of coffee beans. Following a description of the coffee fruit tissues, this review presents some data
concerning biochemical, enzymatic and gene expression variations observed during the coffee fruit development. The latter will
also be analyzed in the light of recent data (electronic expression profiles) arising from the Brazilian Coffee Genome Project.
... Fertilization in C. arabica happens around 24 hours after pollination and the first cell division of the endosperm occurs 21-27 days after fertilization. The first zygote division occurs 60-70 days after pollination [81,6,9]. N.B. ...
Arabica coffee, native to Ethiopia, is esteemed for its exceptional quality and dominates the global specialty coffee market. As the primary cultivated coffee species, it accounts for approximately 60–65% of global coffee production. The genetic diversity of Arabica coffee, shaped through natural evolution and human domestication, is a cornerstone of its adaptability and resilience against biotic and abiotic stresses. Domestication syndrome traits such as reduced seed dispersal, compact growth, and increased uniformity have facilitated its cultivation, yet these traits have inadvertently narrowed its genetic base, making the crop more vulnerable to environmental and pathogenic threats. The genetic makeup of Arabica coffee is unique, with an allotetraploid genome that combines contributions from two diploid species, Coffea canephora and Coffea eugenioides. Despite its evolutionary significance, Arabica coffee exhibits relatively low genetic variation compared to other Coffea species. This limited diversity heightens its susceptibility to genetic erosion caused by deforestation, climate change, and unsustainable monoculture practices. Conservation efforts are crucial to preserving Arabica’s genetic resources, employing both ex-situ and in-situ strategies. Ex-situ methods include seed banks, cryopreservation, and field gene banks, while in-situ conservation protects wild populations in their natural habitats. Modern biotechnological tools such as molecular markers, genetic mapping, and somatic embryogenesis enhance the precision and efficiency of germplasm conservation and utilization. Breeding programs aim to address the challenges posed by climate change, pests, and diseases by developing varieties with enhanced drought tolerance, disease resistance, and higher yields. Hybrid vigor (heterosis) has shown promise in boosting adaptability and productivity. While vegetative propagation ensures uniformity and retention of elite traits, it limits genetic recombination, which is vital for long-term adaptability. In contrast, seed-based propagation facilitates genetic improvement but may compromise trait consistency. Notable achievements in breeding include improved cultivars like Geisha, SL28, and F1 hybrids, which balance productivity with stress resilience. Preserving Arabica coffee’s genetic base and advancing breeding efforts remain essential to securing the crop’s future and maintaining its contribution to global agriculture and livelihoods.
... During coffee seed development, the endosperm grows inside the seed, occupying the space left by the perisperm, the internal cells of which are progressively digested. The endosperm replaces completely the perisperm, of which only the thin silverskin remains (Mendes 1941;Dedecca 1957). In view of this peculiar origin, silverskin is particularly appropriate to be studied from a taxonomical perspective. ...
Coffea liberica originally found near Monrovia in Liberia is the third commercially exploited coffee species known for its larger cherries, compared with those of Coffea arabica or Coffea canephora; it contributes less than one per cent of the marketed coffee. The latter reflects in part the beverage quality being inferior to that of Arabica and in part the agronomical performance not satisfying when compared with those of Robusta. However, this species remains still attracting for some genetical characteristic like certain pest resistance genes in breeding programs as the resistance to coffee leaf rust conferred by the SH3 locus.
Currently, all Liberica taxa were grouped in one species, C. liberica W. Bull ex Hiern that included two varieties, C. liberica var. liberica, C. liberica var. dewevrei (De Wild. and T. Durand) Le Brun, and a form C. liberica f. bwambensis Bridson. The taxonomic differences between the two varieties still raise doubts that leave the question ‘species or variety?‘ still open. For this reason, the search of possible traits or molecular markers able to discriminate and shed light on these doubts has never stopped. In this paper we focus our attention on two characteristics not yet investigated in detail: silverskin tissue and seed diterpenes.
For the first time, an in-depth microscopic study of silverskin morphology was used to discriminate liberica from dewevrei coupled with the diterpenes characterization, the major components of the unsaponifiable fraction of seed lipids, already known as molecular markers and efficiently used for coffee species authentication purposes.
... The endocarp which is brown encloses the seed. The endosperm is a living tissue, contain a hard external region and soft internal region, which surround the embryo (Krug and Carvalho, 1939;Mendes, 1941;Dedecca, 1957;De Castro and Marraccini, 2005). The tissue of the endosperm has a high content of polysaccharides (Wolfrom et.al., 1961). ...
Coffee is an important commodity crop that plays vital role in socio-economy of more than 50 countries. Coffee belongs to the genus Coffea on the family Rubiaceae and it was believed to be originated from tropical Africa. Coffea species were grouped into four sections (Agrocoffea, Paracoffea, Mascarocoffea,Eucoffea). The two most important commercial species are Coffea arabica and Coffea canephora. All the species are diploid with 2n=2x=22 chromosomes except C arabica which is tatraploid with 2n=4x=44. Evaluation of the genetic diversity and available resources with the genus is an important step in coffee breeding. A variety of techniques like morphological, biochemical and genetic markers had been used to measure genetic variation of Coffea species. Coffea arabica has been found to have low polymorphic compared to other species. Coffee is prone to lot of diseases infestation. Two most prominent of them are coffee berry disease and coffee leaf rust which impaired photosynthesis, premature defoliation and reduced folia initiation. Coffee especially C arabica and C canephora are susceptible to insect pest. The most important insect pests are leaf miner and coffee stem borer. Caffeine is the most important chemical component of coffee beans and it varies in value (0.8% and 1.4% in Arabica coffee and 1.7% and 4.0% for canephora). Other components of coffee beans are cellulose, minerals, sugars, lipids, tannin and polyphenols. Coffee storage behavior is intermediate and low temperature is detrimental to the surviving of coffee seeds. Abscisic acid (ABA) induces dormancy and inhibit germination and seed priming is used to enhance uniformity of germination for better crop establishment. The effect of shade on coffee are higher in coffee bean weight, larger bean size, higher antioxidant activity with total phenolic content, and higher chlorogenic acid content.
... Le café a fait l'objet de nombreuses recherches dans le monde, afin de mieux connaître et d'estimer le patrimoine génétique des caféiers, mais aussi pour d'autres domaines, par exemple les différents processus d'hybridation qu'ont connus ces espèces, les processus de floraisons… etc., (Mendes A. J. T., 1941 ;Krug C. A., 1949 ;Medina D. M., 1965 ;Le Pierrès, D., 1999 ;Noirot M., et al., 2003 Ainsi la diversité génétique de Coffea arabica, de ces cultivars et des autres espèces de caféiers, ont été estimées lors de différentes études dans le monde, en étudiant l'ADN à l'aide de : ...
https://dumas.ccsd.cnrs.fr/dumas-01265034
Première île du « Nouveau Monde » à avoir accueilli pour la première fois le café : Coffea Arabica variété Typica en 1720, la Martinique pourtant ne connait aujourd’hui, plus aucune véritable plantation de caféiers. Or elle dispose de la variété Typica, aux origines historiques remarquables et aux valeurs sensorielles globalement reconnues dans le monde. La relance de la culture du café en Martinique présente aujourd’hui plusieurs enjeux. D’un point de vue économique, il s’agirait de lancer un produit de terroir à haute valeur ajoutée, d’un point de vue historique et culturel c’est une façon de se réapproprier un patrimoine historique et de le valoriser, et d’un point de vue agronomique il s’agit de mettre en valeur la biodiversité utile. Pour rendre réelle ces perspectives, cette présente étude s’attache surtout et d’abord à traiter l’aspect agro-écologique. Autrement dit pour relancer la culture, il est nécessaire de connaître les milieux potentiellement aptes de nos jours à accueillir la culture de café Typica, vis-à-vis des exigences éco-climatiques spécifiques à l’espèce, puisqu’il n’y a plus de plantations de café sur l’île pouvant servir « d’indicateur » de milieux favorables. L’objectif final, à l’aide d’un Système d’Information Géographique (SIG), est de cartographier les milieux propices de nos jours au café arabica variété typica en Martinique. Puis l’étude permet aussi d’analyser l’impact du changement climatique sur les possibilités de culture du café Arabica variété Typica en Martinique durant les prochaines années, au regard de sa faible tolérance pour la hausse des températures.
Mots-clés : Coffea arabica var. typica, profil écologique, facteurs éco-climatiques, spatialisation, biotopes, Martinique, changement climatique.
... In the dry seed, the role of this envelope is to prevent the diffusion of solutes, but not water (Welbaum and Bradford 1990). Although in the case of the grain of coffee species the storage tissue was originally suggested to correspond to perisperm (Houk 1938), it is now identified as endosperm (Mendes 1941). Here, during development the grain is dominated by a well-developed maternal perisperm tissue up to approximately the halfway stage of maturation, following which the locular space is progressively filled with endosperm up to full grain maturity (Rogers et al. 1999). ...
Sugarbeet is a crop of high economic importance because it is one of the two main sources of plant sugar, the other being sugarcane. The sugarbeet seeds have the peculiarity of containing at maturity a large starchy storage tissue, called the perisperm. In contrast to the well-documented cereal endosperm, the physiology of this perisperm is completely unknown. Here, we used proteomics of perisperm isolated either from dry mature or imbibed sugarbeet seeds to unravel the mechanisms of starch remobilization during germination. We also carried out a comparative proteomics analysis with the perisperm isolated from the dry mature sugarbeet seeds. We observed an accumulation of α-amylase in the perisperm isolated from imbibed whole seeds but not from the isolated imbibed perisperm alone, suggesting a role of the embryo in triggering the accumulation of this starch-mobilizing enzyme in the perisperm during germination. In this way, the mechanisms occurring in the sugarbeet seed perisperm during germination would appear to be similar to those documented for the endosperm of cereals. In contrast, an accumulation of β-amylase and α-glucosidase was observed in the isolated imbibed perisperm, suggesting that the embryo was not mandatory for induction of these enzymes in the perisperm during imbibition.
... Leaves and fruits of C. arabica were collected from a tree growing at the experimental arca ofour department. Immature fruits were considered those with ivory and opaque endosperm, as described by Mendes (1941) . Matute fruits were eonsidered those with hardened endosperm. ...
... In the later stage the locular space of seeds is progressively filled with endosperm, up to full seed maturity. 43,44 Whole fruits were therefore used in the early stages (stages a-d), whereas in the later stages (stages e and f) the pericarp and seeds were separated and used. Only fruit and seed weights are shown in Figure 3.4 to keep the figure simple, but the pericarp weights in stages e-g can immediately be calculated as the fruit weight minus the seed weight. ...
Trigonelline (N-methylnicotinic acid) is a major alkaloid in coffee seeds. During roasting, it is converted to nicotinic acid (niacin) and other metabolites that are related to the taste and aroma of coffee beverage. Trigonelline is present in all parts of coffee plants. Its content in coffee seeds is 1–3% dry weight. In contrast to caffeine, there has been little study of the biosynthesis and degradation of trigonelline in Coffea arabica and Coffea canephora. This study reveals the outline of trigonelline metabolism in Coffea plants. The major biosynthetic pathway is NAD → nicotinamide mononucleotide → nicotinamide riboside → nicotinamide → nicotinic acid → trigonelline. High trigonelline biosynthesis activity was found in young fruits and in the pericarp of developing fruits. Trigonelline synthase activity was detected in Coffea plants, but the gene encoding this enzyme has not yet been cloned. A useful biotechnology for creating trigonelline-rich coffee beans is set out.
... The coffee embryo is surrounded by endosperm tissue (Krug and Carvalho 1939;Mendes 1941). The endosperm cells possess thick cell walls, which are largely composed of mannan-rich polymers with 2 % of galactose (Wolfrom et al. 1961;Bewley et al. 2012). ...
Germination of coffee (Coffea arabica L.) seed is slow and uneven. Its germination is the net result of events that occur simultaneously in the embryo and endosperm and which are controlled by abscisic acid (ABA). The aim of the study was to monitor the expression of genes related to the cell cycle and to cell wall modifications, including an actin (ACT), a cyclin-dependent kinase (CDK2a) and α-expansin (α-EXP) in the embryo, and α-galactosidase (α-GAL), β-mannosidase (LeMSIDE2), endo-β-mannanase (MANA) in the micropylar endosperm. The first seed germinated after 5 days of imbibition and 50 % germination was reached after 10 days. The embryo grew inside the seed prior to radicle protrusion and ABA inhibited both embryo growth and radicle protrusion. The expression of the genes associated with the embryo growth increased during germination and ABA partially inhibited expression. The expression of β-mannosidase and endo-β-mannanase increased during imbibition and ABA completely inhibited expression of these genes. However, α-galactosidase displayed a more constitutive expression and was less affected by ABA. ABA plays a dual role in the regulation of coffee seed germination; it concomitantly controls both endosperm weakening and embryo growth.
... Para Coffea arabica requiere de 6 a 8 meses para madurar, (30). En este caso solamente la capa externa del tejido perisperma permanece circundante al endosperma, (31). El endosperma actualmente corresponde al grano que, después de los tratamientos postcosecha, formará el "café verde" que es vendido en los mercados internacionales. ...
... Leaves and fruits of C. arabica were collected from a tree growing at the experimental area of our department. Immature fruits were considered those with ivory and opaque endosperm, as described by Mendes (1941). Mature fruits were considered those with hardened endosperm. ...
The coffee species Coffea dewevrei and Coffea arabica have marked differences in caffeine metabolism and the control of the caffeine content during fruit ripening and leaf aging is still not clear. The aim of this work was a detailed investigation on the alkaloid degradation in young and aged leaves, and immature and mature fruits of these species. Young and aged leaves, and immature and mature fruits were fed with [2- 14C] caffeine. After an incubation period they were extracted for [2- 14C] caffeine and metabolites and analysed by reversed-phase liquid chromatography and radiocounting of collected fractions. In leaves and fruits of Coffea dewevrei there were higher degradation rates of caffeine. In both species, compared to young tissues, aged leaves and mature fruits presented lower capacity to degrade the alkaloid, what was shown by the low radioactivities detected in the metabolites formed in the degradation pathway. Radioactivity was detected in 7-methylxanthine, which is also a precursor in the caffeine biosynthesis. The data support the conclusion that the ratio between biosynthesis and biodegradation controls the variation of the caffeine content during fruit ripening and leaf aging in C. arabica and C. dewevrei.
... Although mature AC1 fruits were smaller than mature MN fruits, the pattern of AC1 fruit development was similar to that of MN fruits. During coffee fruit development, the perisperm is substituted by the endosperm (Mendes, 1941;DeCastro and Marraccini, 2006), which pattern was similar in both MN and AC1. However, closer inspection of our data suggests that the AC1 fruits developed earlier than the MN fruits. ...
We compared the biochemical characteristics of the beans of a naturally decaffeinated Arabica coffee (AC1) discovered in 2004 with those of the widely grown Brazilian Arabica cultivar "Mundo Novo" (MN). Although we observed differences during fruit development, the contents of amino acids, organic acids, chlorogenic acids, soluble sugars and trigonelline were similar in the ripe fruits of AC1 and MN. AC1 beans accumulated theobromine, and caffeine was almost entirely absent. Tests on the supply of [2-14C] adenine and enzymatic analysis of theobromine synthase and caffeine synthase in the endosperm of AC1 confirmed that, as in the leaves, caffeine synthesis is blocked during the methylation of theobromine to caffeine. The quality of the final coffee beverage obtained from AC1 was similar to that of MN.
... Iniciaram-se depois as análises genéticas dos característicos das principais variedades dessa espécie (10) e realizaram-se também observações quanto à biologia da flor (2) e contagem de cromosômios das formas existentes (12,18). Efetuaram-se pesquisas relativas à micro e megasporogênese (14,19,21,22,23), desenvolvimento do endosperma (16) e, em alguns casos, sobre a morfologia dos cromosômios (15). ...
A hibridação como método de melhoramento do cafeeiro, oferece amplas possibilidades que ainda se acham pouco exploradas. Para o caso da espécie C. arabica, a hibridação entre suas variedades, além de fornecer dados seguros sôbre a constituição genética, permite também a verificação de ocorrência da heterose, o melhoramento sem mudança dos caracteres das variedades, ou sintetização de estruturas genéticas novas. Os cruzamentos interespecíficos poderão contribuir decisivamente para a solução do problema da melhoria da qualidade do produto e dar indicações a respeito das relações das várias espécies e da reação dos fatôres genéticos de uma espécie em ambientes genéticos diversos. Cêrca de 2500 híbridos se acham em estudo na Secção de Genética, envolvendo plantas da mesma variedade, plantas de variedades diferentes e cafeeiros pertencentes a espécies distintas. As diversas possibilidades dêsses cruzamentos no melhoramento do cafeeiro são indicadas, chamando-se especial atenção para os híbridos interespecíficos, principalmente aquêles que envolvem a espécie tetraplóide C. arabica e outras espécies diplóides, como C. canephora, C. Dewevrei e C. congensis. Êstes híbridos triplóides, após duplicação do número de cromosômios, poderão constituir fonte de novas formas de Coffea, permitindo a expansão do cultivo do café era São Paulo.
... arabica) fruit is a drupe containing two seeds. The coffee seed is comprised of an endosperm that envelops an embryo and a peripheral spermoderm or 'silver skin' (Krug and Carvalho, 1939; Mendes, 1941). The coffee endosperm is composed of a hard greenish tissue and is divided into a hard external endosperm and a soft internal endosperm (Dedecca, 1957). ...
Coffee propagation is performed by seeding. However, germination in coffee seed is slow and uneven.
Indeed, the production of plants in field is affected by environmental factors, which retards the
germination rates and, in consequence, the number of plants obtained. Plant tissue culture provides the
possibility of applying different growing conditions, such as different types of media and using
phytoregulators, to induce a response in order to shorten zygotic embryo germination times. Therefore,
due to limited understanding of growing zygotic embryos of coffee, we evaluated the effect of certain
plant growth regulators on zygotic embryo germination of Coffea arabica. To study germination times,
we evaluated the effects of culture media with incubation either at photoperiod or darkness and with
certain plant growth regulators [gibberellic acid (GA), abscisic acid (ABA), indole-3-butyric acid (IBA),
naphthalene acetic acid (NAA), kinetin (KIN) and salicylic acid (SA), at concentrations of 0.1, 1, and 10
mg l-1 each]. Zygotic embryos were cultured on Murashige and Skoog (MS), and Gamborg media at
different concentrations (1/1, ½, and ¼ of its ionic strength) under conditions of darkness and
photoperiod. Germination times of zygotic embryos cultured in MS medium had a mean of 5.1 days,
whereas zygotic embryos cultured in B5 medium germinated with a mean of 7.5 days. Among the plant
growth regulators used, gibberellic acid at 0.1 mg l-1 proved to be the most efficient in germinating
zygotic embryos, with 100% germination reached by the 5th day. Germination time of zygotic embryos
was 12 days when ABA at 0.1 mg l-1 was used; however, ABA inhibited germination of embryos when it
was used at concentrations of 1.0 and 10 mg l-1 since only 10% germination occurred. Regarding the
germination times of zygotic embryos of coffee, the priority order of efficiency was GA > KIN > SA > IBA
> NAA > ABA. Also, with the exception of SA, concentrations higher than 0.1 mg l-1 increased the
zygotic embryo germination rates.
... While most of the pollen studies of Coffea have focussed on the morphology, development, viability, germination and importance to taxonomy (Mendes, 1949;Kwack, 1965;Sybenga, 1960;Chinnappa & Adams, 1974;Chinnappa & Warner, 1981;Ram et al., 1988;Arowolo, 1991;Lashermes et al., 1996b), there are also a few studies undertaken on the storability of Coffea pollen (Carvalho & Monaco, 1969;Ferwerda, 1937Ferwerda, , 1969Walyaro & van der Vossen, 1977). Unlike seed, pollen is not a conventional material for germplasm storage and the main use of pollen is in coffee breeding, since crosses may have to be made between trees which do not flower simultaneously or grow far apart (Walyaro & van der Vossen, 1977). ...
No single conservation technique can adequately conserve the full range of genetic diversity of a target species or genepool. To optimize the efficiency of germplasm conservation, a range of conservation techniques needs to be applied simultaneously. In this paper we review the progress made in the application of both in situ and ex situ complementary conservation strategies and techniques to the conservation of the genus Coffea and identify areas where more research work is required. Traditionally, Coffea species have been conserved ex situ as living plants in field genebanks due to their intermediate seed storage behaviour. However, progress made in the field of biotechnology in recent years have made it possible to envisage the use of in vitro, slow growth and cryopreservation for medium- and long-term conservation of Coffea germplasm, respectively. In situ conservation is also an important option for long-term conservation, but there are no genetic reserves specifically set up for conserving Coffea. Protected areas and managed reserves offer the best opportunities for conserving Coffea. A case study for Mascarene Coffea in Mauritius is presented and a strategy for their conservation is discussed.
... In the initial stage of coffee fruit development, the fruits consist of pericarp and perisperm. In the later stage, the locular space of seeds is progressively filled with endosperm, up to full seed maturity [27,28]. Whole fruits were therefore used in the early stages, whereas in the later stages, pericarp and seeds were separated and used in the estimation of caffeine and trigonelline content and of metabolic activities. ...
Caffeine and trigonelline are major nitrogenous alkaloids found in coffee seeds. Accumulation of these alkaloids in two cultivars of Coffea arabica and in a cultivar of Coffea canephora seeds was monitored. Growth stages are specified by letters, A to G. They correspond to the pinhead and small (A), rapid expansion and pericarp growth (B), endosperm formation (C), early dry matter accumulation (D), mature (green) (E), ripening (pink) (F) and fully ripened (red) (G) stages. Caffeine and trigonelline content increased at stages D and E. The concentrations of caffeine in ripe seeds (stage G) of the two cultivars of C. arabica and C. canephora seeds were respectively 1.0% and 1.9% dry weight. A high biosynthetic activity of caffeine, which was estimated via the incorporation of [8-14C]adenine into purine alkaloids, was found in whole fruits (perisperm and pericarp) in stages B and C, and in developing seeds (endosperm) in stages D and E. The biosynthetic activities of caffeine were reduced in both pericarp and seeds in stages F and G. In C. arabica cv. Mokka and in C. canephora, the transcripts of CmXRS1, CTS2 and CCS1, three N-methyltransferase genes for caffeine biosynthesis, and of methionine synthase gene (MS) were detected in every stage of growth, although the amounts of these transcripts were significantly less in stage G. The pattern of expression of genes for caffeine synthesis during growth is roughly related to the in situ synthesis of caffeine from adenine nucleotides, although exceptions were found in the very early and later stages of fruit growth. The amounts of the transcripts of CmXRS1, CTS2 and CCS1 were higher in seeds than in pericarp, but reverse was true for MS transcripts in developing coffee fruits. Similarly, caffeine synthase (N3-methyltransferase) activity was also higher in seeds than in pericarp. Concentrations of trigonelline in ripe seeds (stage G) of C. arabica cv. Mokka, C. arabica cv. Catimor and C. canephora were ca. 1.3%, 1.0% and 1.4% of dry weight, respectively. High biosynthetic activity of trigonelline was found in young fruits (stages A–C) and in the pericarp of developing fruits (stage E). The biosynthetic activity was reduced markedly in seeds at stages F and G. These results suggest that active trigonelline biosynthesis occurs in the pericarp of coffee fruits. Although the final concentration of caffeine and trigonelline varies in the three Coffea plants, the patterns of fluctuations of the caffeine and trigonelline biosynthetic activity in all Coffea plants are all similar.
... The mature coffee grain has been convincingly identified as endosperm [18] and not perisperm as suggested previously [19]. This identification has been supported by more recent studies [20][21][22]. ...
Changes in concentration of mono- and oligosaccharides, sugar alcohols, myo-inositol, carboxylic acids and inorganic anions in coffee grains were analysed during grain development in three cultivars of Coffea arabica L (Arabica) and two of C. canephora L var. Robusta (Robusta) by high performance anion exchange chromatography coupled to pulsed electrochemical detection (HPAE-PED). The majority of the components analysed either decreased in concentration during the first half of the development period or accumulated steadily during the latter half of the period. The profiles are taken to indicate relationships between the perisperm, the principal tissue in the young grain and the endosperm during maturation. While most of the free sugar in the mature grain is accounted for by sucrose, fructose and glucose are both at higher concentrations in the perisperm. Considerable amounts of myo-inositol (3–4% dry weight (DW)) are found in young grains, while only the phosphorylated form phytic acid occurs in mature grains (0.3–0.6% DW). Quinic acid, which is present in very low amounts in mature endosperm, represents between 6 and 16% DW in young grains, this possibly being the major precursor pool for the high amounts of chlorogenic acids (5–10% DW) which are a characteristic of mature coffee grains. Of the other organic acids analysed, citric and malic acids are dominant in the mature grain, with higher concentrations in Arabica than Robusta. The results are discussed with respect to the potential implications for transport mechanisms in developing coffee grains and also the importance of the compounds analysed for industrial quality and flavour.
... In coee fruits, the ®rst cellular divisions of the endosperm start 20±30 days after anthesis and pollination (Mendes, 1941). As the endosperm grows, it occupies the inner fruit space, replacing the perisperm, until it reaches full size, at approx. ...
Polyphenol oxidase (PPO) was characterized in partially purified extracts of leaves (PPO-L) and fruit endosperm (PPO-E) of coffee (Coffea arabica L.). PPO activity was higher in early developmental stages of both leaves and endosperm of fruits. Wounding or exposure of coffee leaves to methyl jasmonate increased PPO activity 1.5–4-fold. PPO was not latent and was not activated by protease treatment. PPO activity was stimulated 10–15% with sodium dodecyl sulphate (SDS) at 0.35–1.75 mM, but at higher concentrations activities were similar to the control samples, without detergent. Prolonged incubation of extracts with trypsin or proteinase K inhibited PPO activity but pepsin had no effect. Inhibition of PPO with proteinase K was increased in the presence of SDS. PPO activity from both tissues was optimal at pH 6–7 and at an assay temperature of 30°C. Activity was highest with chlorogenic acid as substrate with a Km of 0.882 mM (PPO-L) and 2.27 mM (PPO-E). Hexadecyl trimethyl-ammonium bromide, polyvinylpyrrolidone 40, cinnamic acid and salicylhydroxamic acid inhibited PPO from both tissues. Both enzymes were inactivated by heat but the activity in endosperm extracts was more heat labile than that from leaves. The apparent Mr determined by gel filtration was 46 (PPO-L) and 50 kDa (PPO-E). Activity-stained SDS–polyacrylamide gel electrophoresis (PAGE) gels and western blots probed with PPO antibodies suggested the existence of a 67 kDa PPO which is susceptible to proteolytic cleavage that generates a 45 kDa active form.
Die Kaffeebohne ist der weitgehend von der Samenschale befreite Samen verschiedener Arten sowie deren zahlreichen Kulturformen und Kreuzungen der Gattung Coffea L., die im tropischen und subtropischen Afrika und Asien (bis zu den Sundainseln) heimisch ist und außerdem in Mittel- und Südamerika kultiviert wird. Besonders in neuerer Zeit ist durch die Arbeiten von Cheney (1925), Chevalier (1929, 1940, 1942, 1947), Houk (1939), Krug-Mendes-Carvalho (1939), de Wildeman (1941), Lebrun (1941), Carvalho (1945/46, 1952), Coste (1955), Haarer (1956, 1962), Cramer (1957), Wellman (1961) und Léon (1962) eine weitgehende Klärung der recht komplizierten systematischen Verhältnisse und der Nomenklatur erfolgt.
Die Befruchtung der Archegoniaten (Bryophyten und Pteridophyten) ist dadurch charakterisiert, daß sich die befruchtungsfähigen, frei beweglichen männlichen Gameten (Spermatozoiden) in einem die Antheridien und Archegonien bedeckenden wäßrigen Medium, in das sie von den Antheridien entleert wurden, aktiv zu den Archegonien — chemotaktisch von diesen angelockt — bewegen. Durch den von Schleim erfüllten Halsteil des Archegoniums gelangen sie in unmittelbare Nähe der Eizelle, worauf die Vereinigung der männlichen und weiblichen Fortpflanzungszellen und die Verschmelzung der männlichen und weiblichen Kerne die Befruchtung abschließt.
Drawing from a lifetime of teaching botany, Dr. Nels Lersten presents the study of the structures and processes involved in the reproduction of plants in his text Flowering Plant Embryology. This richly illustrated reference text, with more than 350 figures and illustrations, presents general angiosperm embryology as it applies to economically important plants. The unique focus on economically important species increases the relevance of this book to today's students and researchers in the plant sciences. Lersten emphasizes the plant species that affect human livelihood, including weeds and other cultivated plants that are used for commercial products. Selected from the thousands of economically important plants, the examples chosen for illustration and discussion are familiar, especially to students from North America, Northern Europe, and Japan. Although the emphasis of this book is economically important plants, the information within applies to almost all flowering plants. Extremely readable and well-written, this book is neither dense nor academic in tone. Lersten treats topics with a uniformity of style and organization that enhances comprehension. Terms are well-defined and the derivation of each is explained to further facilitate student learning. The book presents research results, hypotheses, and speculations about why things are as they are, with supporting facts and specific examples that provide a firm foundation for students' understanding of embryological diversity among economic plants.
Trigonelline (N-methylnicotinic acid) is a major alkaloid in coffee seeds. During roasting, it is converted to nicotinic acid (niacin) and other metabolites that are related to the taste and aroma of coffee beverage. Trigonelline is present in all parts of coffee plants. Its content in coffee seeds is 1–3% dry weight. In contrast to caffeine, there has been little study of the biosynthesis and degradation of trigonelline in Coffea arabica and Coffea canephora. This study reveals the outline of trigonelline metabolism in Coffea plants. The major biosynthetic pathway is NAD → nicotinamide mononucleotide → nicotinamide riboside → nicotinamide → nicotinic acid → trigonelline. High trigonelline biosynthesis activity was found in young fruits and in the pericarp of developing fruits. Trigonelline synthase activity was detected in Coffea plants, but the gene encoding this enzyme has not yet been cloned. A useful biotechnology for creating trigonelline-rich coffee beans is set out.
Woody plants such as trees have a significant economic and climatic influence on global economies and ecologies. This completely revised classic book is an up-to-date synthesis of the intensive research devoted to woody plants published in the second edition, with additional important aspects from the authors' previous book, Growth Control in Woody Plants. Intended primarily as a reference for researchers, the interdisciplinary nature of the book makes it useful to a broad range of scientists and researchers from agroforesters, agronomists, and arborists to plant pathologists and soil scientists. This third edition provides crutial updates to many chapters, including: responses of plants to elevated CO2; the process and regulation of cambial growth; photoinhibition and photoprotection of photosynthesis; nitrogen metabolism and internal recycling, and more. Revised chapters focus on emerging discoveries of the patterns and processes of woody plant physiology. * The only book to provide recommendations for the use of specific management practices and experimental procedures and equipment * Interdisciplinary approach will appeal to a broad range of scientists, researchers, and growers * Thoroughly updated with the latest research devoted to woody plants.
The germination process of coffee beans occurs while these non-orthodox seeds are still inside the cherry. A range of metabolic reactions related to germination have already been induced in harvested coffee seeds at this time. The germination process is asynchronous and the evolution of germination depends heavily on how the beans are processed post-harvest.The microflora associated with the coffee cherry surface comprises several bacterial, yeast and fungal species and greatly affects the processing of coffee beans. In particular, indigenous (or applied) lactic acid bacteria and yeast are essential to ferment the coffee berry mucilage after de-pulping. On the other hand, the fungi negatively affect coffee quality, especially regarding food safety, spoilage, off-tastes and mycotoxin contamination. The first part of this review gives an overview of C. arabica and C. robusta germination. Additionally, plant growth hormones contributing to the process are also discussed. The second section deals with microflora associated with the beans during harvesting and processing exploring its effects on coffee quality and safety. Biological control strategies for improving the microbial safety of coffee beans are also discussed.
O presente estudo anatômico de Coffea arabica L. var. typica Cramer tem por finalidade fornecer informações básicas necessárias ao estudo da anatomia comparada das principais espécies e variedades de cafeeiros, cultivadas no Estado de São Paulo. Nesta primeira contribuição o autor realiza o estudo anatômico detalhado dos órgãos vegetativos e reprodutivos da variedade typica, não se limitando apenas à anatomia descritiva dos diversos órgãos, mas também, sempre que possível, discutindo o desenvolvimento ontogenético das diversas partes do cafeeiro. No estudo da raíz e do caule procurou-se estabelecer a duração do desenvolvimento primário, assinalando o local de aparecimento, primeiramente do câmbio vascular e, posteriormente, do felógeno ou câmbio suberoso. Na discussão da anatonia das folhas mereceu especial atenção o estudo das domácias, sua morfologia e possível função. As flores são estudadas detalhadamente nos seus diversos elementos. Nos capítulos referentes à anatomia do fruto e da semente, além do estudo puramente descritivo das suas estruturas são ainda discutidas as diversas modificações verificadas durante o desenvolvimento do ovário e dos óvulos, respectivamente em fruto e sementes.
Em Coffea arabica a côr amarela do endosperma é determinada por um fator genético recessivo cera (ce ce). Endospermas que tragam uma ou duas doses do dominante Ce são de côr verde. Êsse fenômeno de xenia foi utilizado para determinar a velocidade de penetração do tubo polínico através do estilo. O método adotado foi o da polinização simultânea ou com Uoras de intervalo, dos mesmos estigmas com pólen Ce e pólen cc. Em seguida, de espaços a espaços de tempo eram eliminados os estilos. Verificou-se que sem a introdução do tubo polínico no interior do ovário não se produz o estímulo para a frutificação. O pólen estranho emite tubos po-linicos mais velozes nos estilos da varietlade cêra do que o próprio pólen. No primeiro caso, os tubos polínicos levam 24 a 48 horas para se introduzir na cavidade ovariana; na autofecundação êsse tempo se eleva para 48 a 68 horas. Comparando tais resultados com os obtidos anteriormente nas variedades typica, semperflorens e no café Mundo Novo, conclui-se que a velocidade do tubo polinico varia também de acôrdo com a variedade ou com as condições ambientes na ocasião da polinização.
The time required for development of the fruit of Coprosma lucida from fertilisation to maturity was 17 months, whereas the period was 6 months in other Coprosma species studied. A prolonged “pin-head” stage of fruit development was responsible for the delay in maturation. Application of the plant growth substances 2,4-D and GA3 accelerated development of the fruit.
The embryology ofOldenlandia umbellata Linn. has been investigated. Floral parts arise in acropetalous succession. A transection of an young anther shows a group
of microscope mother cells followed by a layer of tapetum, a middle layer, an endothecium and an epidermis. The uninucleate
tapetum is of the glandular type. Microspore tetrads are tetrahedral and isobilateral. The pollen grain is binucleate at the
time of anther dehiscence and the endothecium fibrillar. A hypodermal archesporial cell directly functions as the megaspore
mother cell. Embryo sac development follows the Polygonum type. Fertilisation is porogamous. Endosperm is free nuclear and
embryogeny conforms to the solanad type.
Uma pequena porcentagem de frutos sem sementes é comum às plantas de tôdas as variedades de Coffea arabica, parecendo tratar-se de um fenômeno puramente fisiológico. No café Mundo Novo porém, além dêste tipo de plantas, há outras com elevada porcentagem de lojas vazias ("chochos"). Constituindo isto um grave defeito para uma variedade comercial, procurou-se estudar a sua causa. As observações feitas no processo da microsporogênese mostraram irregularidades na distribuição dos cromossômios. Sendo encontradas tanto nas plantas de alta porcentagem como nas de baixa porcentagem de chochos, não deve residir nessas anomalias a causa procurada. Em estudos comparativos dos dois tipos de plantas do Mundo Novo e da variedade bourbon, pôde-se verificar : a) que, em linhas gerais, o processo da formação do saco embrionário e o desenvolvimento do endosperma e do embrião são idênticos, havendo um ligeiro atrazo para as plantas Mundo Novo ; b) que nestas últimas existem anormalidades diversas no saco embrionário, em proporção muito mais elevada do que no bourbon. Ocorrendo com igual freqüência nos dois tipos de plantas do café Mundo Novo, estas anormalidades também não devem se relacionar com a formação de chochos. Estudos realizados em frutos de diversas idades, permitiram relacionar a alta freqüência de lojas vazias com o aparecimento de uma estrutura anormal, em forma de disco, encontrada no interior dos restos de perisperma. Êste "disco" (com cêrca de 3 mm de diâmetro) só apareceu na planta de alta freqüência de chochos, não tendo sido constatado na planta Mundo Novo de baixa freqüência de chochos, nem na planta bourbon. O exame citológico revelou que essa estrutura é constituida de endosperma, contendo um embrião anormal ; de côr clara a princípio, torna-se pardacenta à medida que degenera ; recebeu a denominação de "endosperma discóide". De oito plantas examinadas a seguir, encontrou-se endosperma discóide nas quatro que produzem alta porcentagem de lojas sem sementes, o que permitiu classificar as plantas Mundo Novo em duas categorias : 1) plantas onde ocorre o "disco" ; 2) plantas nas quais o "disco" não ocorre. A alta freqüência de chochos nessa variedade está, pois, condicionada à presença do endosperma discóide. Os autores sugerem uma hipótese genética para explicar êsse novo fenômeno : plantas de alta freqüência de chochos são heterozigotas para um par de fatores, que na condição duplamente recessiva têm ação letal ; como conseqüência, há paralização do endosperma no início do seu desenvolvimento, e, em seu lugar, é encontrado o "disco".
Em um conjunto de cafeeiros existentes em Mundo Novo, hoje Urupês, na região Araraquarense do Estado de São Paulo, foram feitas seleções de vários cafeeiros baseando-se no seu aspecto vegetativo, na produção existente na época da seleção e na provável produção do ano seguinte. Estudou-se a origem da plantação inicial desse café, tanto em Urupês como em Jaú, chegando-se à conclusão de que é provavelmente originário desta última localidade. Progênies do café "Mundo Novo", anteriormente conhecido por "Sumatra" e derivado de plantas selecionadas em Urupês e Jaú, acham-se em estudo em seis localidades do Estado : Campinas, Ribeirão Prêto, Pindorama, Mococa, Jaú e Monte Alegre do Sul. No presente trabalho são apenas aproveitados dados referentes à variabilidade morfológica e característicos da produção das progênies dos primeiros cafeeiros selecionados em Urupês e estudados em Campinas, Jaú, Pindorama e Mococa. Em tôdas as localidades, observou-se variação nos caracteres morfológicos das progênies, verificando-se a ocorrência de plantas quase improdutivas. A maioria das progênies, no entanto, se caracteriza por acentuado vigor vegetativo. Foram estudadas as produções totais das progénies e das plantas, no período 1946-1951, notando-se que algumas progénies se salientaram pela elevada produção em tôdas as localidades. Os tipos de sementes "moca", "concha" e "chato" foram determinados em amostras de tôdas as plantas, por um período de três anos, notando-se que a variação ocorrida é da mesma ordem que a encontrada em outros cafeeiros em seleção. Procurou-se eliminar, pela seleção, cafeeiros com elevada produção de frutos sem sementes em uma ou duas lojas, característico êsse que parece ser hereditário. Os resultados obtidos de cruzamento entre os melhores cafeeiros "Mundo Novo" de Campinas e plantas da variedade murta, indicaram que esses cafeeiros são do tipo bourbon. Provavelmente, êsses cafeeiros constituem recombinações de um cruzamento primitivo entre o café "Sumatra" e o bourbon. As progênies mais produtivas do café "Mundo Novo" e livres de vários dos defeitos mencionados, já se acham em multiplicação, a fim de, em breve, serem fornecidas sementes aos lavradores, que tanto interêsse têm demonstrado por êsse café.
The growth of a coffee berry and the beans contained therein is the result of a highly complex physiological process carried on in the tree, several recognized shapes of beans emerging as a result of the various factors influencing the growth. In the present study, a quantitative definition has been provided to these shapes at the important wet parchment stage in terms of their length, width, depth and the areas of flat and transverse surfaces, the latter being obtained by a cross-sectioning of the bean. Both Arabica and Robusta varieties have been studied.Empirical equations for various been shapes have been proposed, based on a large number of measurements, to express the correlation between the three principal dimensions of a bean. Another set of suggested equations can be used to predict with reasonableaccuracy either of the two areas from a measurement of any one of these three dimensions. For both the areas, the relationship between the calculated (from a consideration of a truly elliptical shape) and the measured value have also been shown.Arabica and Robusta coffee are seen to have varying characteristics, the former being larger in size with a generally elongated shape longitudinally as well as laterally in comparison with the latter variety.
Polyphenoloxidase (PPO) was purified from coffee beans at the pinhead stage. Purification was carried out by precipitation of contaminating proteins with 30% (NH4)2SO4, dialysis of the supernatant and chromatography on phenyl sepharose and DEAE columns. A purification factor of 364 was obtained. Two bands (29 and 64 kDa) of the purified PPO were detected after SDS-PAGE which presented activity in partially denaturing SDS-PAGE and gave a positive response when probed in Western blots with an apple 27 kDa PPO antibody. It is suggested that the 29 kDa band was a cleavage product of the 64 kDa PPO. The N-terminal sequencing of the 29 kDa protein did not show similarity with others PPOs. Other reports have shown that the 64 kDa is a pre-protein which is converted to a 45 kDa mature form by action of a chloroplastid protease. The 45 kDa was not detected in pinhead fruits but usually detected in the leaves and endosperm of coffee. It is suggested that the appearence of the 45 kDa form might be controlled by the developmental stage of the fruit. Chlorogenic acid was the preferred substrate for the purified PPO.
Various aspects of pollen longevity, in vitro germination of pollen and controlled pollination in Coffea arabica were investigated. High pollen viability could be maintained for more than two years, much longer than previously reported, by storing it under vacuum at 18C. The most satisfactory method of in vitro germination of pollen was the hanging drop in a Van Tieghem cell, with a 10, sucrose solution. For artificial cross-pollination it is necessary to carry out emasculation and bagging at the latest one day before anthesis. The stigmas of unpollinated flowers remained receptive for at least nine days.
Two experiments were conducted to investigate selenite toxicity in coffee (Coffea arabica cv. Catua). In the first aqueous selenite solution (10 M Na2SeO3) was used to infiltrate leaves of an adult coffee plant. The infiltrated leaves and fruits adjacent to them showed enhanced contents of caffeine and soluble sugars. Amino acid contents were not affected, whereas pigments (chlorophylls, carotenoids and xanthophylls) exhibited a significant decrease. In the second experiment, coffee seedlings were irrigated with aqueous selenite solutions (10,100 and 1000 M Na2SeO3) and the first and third pairs of leaves were analyzed. Control plants did not receive selenium. The plants were not different in height, but at the highest selenium concentration showed lower dry matter accumulation in roots and leaves, lower leaf area and thicker leaves. Increases in caffeine and soluble sugars were observed in the first pair of leaves at the highest selenium concentration, although selenium content itself increased steadily with increasing solution concentration. Phenols increased in both leaf pairs and pigments decreased in the third pair. Nitrate reductase activity, measured in the second leaf pair, was much lower at all selenium levels. The profile of free amino acid was altered in leaves of plants treated with selenium.
By constantly improved techniques in selection, cross-pollination and grafting in Java since 1907, and by accompanying studies
in flower biology, fruitsetting and fruit-dropping, increased yields up to 100% are now achieved after two or three generations
of coffee breeding.
This chapter investigates the genetic characters of coffee, which is a woody perennial plant. The genus Coffea(C) is polymorphic. All species so far studied have been found to have 2n=22 chromosomes with the exception of C. arabica that has 2n=44 chromosomes. The haploid form of C. arabica occurs rather frequently and is relatively vigorous. The haploid forms have been used for artificial chromosome duplication and the production of homozygous plants that are of special value for breeding and for the study of mutation rates; both natural and artificially induced. At the beginning of the meiotic prophase, the chromosomes of C. canephora and C. arabica species present heterochromatic; intensively stained regions around the centromeres and faintly stained euchromatic ends. All species of coffee are self-sterile except for C. arabica that is self-fertile. The results derived from the study of natural pollen transmission have shown that C. arabica is predominantly autogamous. The study of several generations, resulting from artificial selfings of several varieties of C. Arabica, have also shown that inbreeding does not have a harmful effect on either plant development or yield.
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