Lychee
Lychee is the sole member of the genus Litchi in the soapberry family, Sapindaceae. It is a tropical tree native to the Guangdong and Fujian provinces of China, where cultivation is documented from 1059 AD. China is the main producer of lychees, followed by India, other countries in Southeast Asia, the Indian Subcontinent and South Africa. A tall evergreen tree, the lychee bears small fleshy fruits; the outside of the fruit is pink-red textured and inedible, covering sweet flesh eaten in many different dessert dishes. Lychee seeds contain methylenecyclopropylglycine which can cause hypoglycemia associated with outbreaks of encephalopathy in undernourished Indian and Vietnamese children who had consumed lychee fruit. Litchi chinensis is the sole member of the genus Litchi in Sapindaceae, it was described and named by French naturalist Pierre Sonnerat in his account "Voyage aux Indes orientales et à la Chine, fait depuis 1774 jusqu'à 1781", published in 1782. There are three subspecies, determined by flower arrangement, twig thickness and number of stamens.
Litchi chinensis subsp. Chinensis is the only commercialized lychee, it grows wild in southern China, northern Vietnam, Cambodia. It has thin twigs, flowers have six stamens, fruit are smooth or with protuberances up to 2 mm. Litchi chinensis subsp. Philippinensis Leenh, it is common in the wild in the Philippines and cultivated. It has thin twigs, six to seven stamens, long oval fruit with spiky protuberances up to 3 mm. Litchi chinensis subsp. Javensis, it is only known in Malaysia and Indonesia. It has thick twigs, flowers with seven to eleven stamens in sessile clusters, smooth fruit with protuberances up to 1 mm. Litchi chinensis is an evergreen tree, less than 15 m tall, sometimes reaching 28 m, its evergreen leaves, 5 to 8 in long, are pinnate, having 4 to 8 alternate, elliptic-oblong to lanceolate, abruptly pointed, The bark is grey-black, the branches a brownish-red. Its evergreen leaves are 12.5 to 20 cm long, with leaflets in two to four pairs. Lychee have a similar foliage to the Lauraceae family due to convergent evolution.
They are adapted by developing leaves that repel water, are called laurophyll or lauroid leaves. Flowers grow on a terminal inflorescence with many panicles on the current season's growth; the panicles grow in clusters of ten or more, reaching 10 to 40 cm or longer, holding hundreds of small white, yellow, or green flowers that are distinctively fragrant. The lychee bears fleshy fruits that mature in 80–112 days depending on climate and cultivar. Fruits vary in shape from round to ovoid to heart-shaped, up to 5 cm long and 4 cm wide, weighing 20 g; the thin, tough skin is green when immature, ripening to red or pink-red, is smooth or covered with small sharp protuberances textured. The rind is inedible but removed to expose a layer of translucent white fleshy aril with a floral smell and a fragrant, sweet flavor; the skin turns dry when left out after harvesting. The fleshy, edible portion of the fruit is an aril, surrounding one dark brown inedible seed, 1 to 3.3 cm long and 0.6 to 1.2 cm wide.
Some cultivars produce a high percentage of fruits with shriveled aborted seeds known as'chicken tongues'. These fruit have a higher price, due to having more edible flesh. Since the perfume-like flavour is lost in the process of canning, the fruit is eaten fresh. Cultivation of lychee began in the region of southern China, going back to 1059 AD, northern Vietnam. Unofficial records in China refer to lychee as far back as 2000 BC. Wild trees still grow on Hainan Island. There are many stories of the fruit's use as a delicacy in the Chinese Imperial Court, it was first described and introduced to the West in 1656 by Michal Boym, a Polish Jesuit missionary. In the 1st century, fresh lychees were in such demand at the Imperial Court that a special courier service with fast horses would bring the fresh fruit from Guangdong. There was great demand for lychee in the Song Dynasty, in his Li chi pu, it was the favourite fruit of Emperor Li Longji's favoured concubine Yang Yuhuan. The emperor had the fruit delivered at great expense to the capital.
The lychee attracted attention of European travellers, such as Juan González de Mendoza in his History of the great and mighty kingdom of China, based on the reports of Spanish friars who had visited China in the 1570s gave the fruit high praise: hey haue a kinde of plummes, that they doo call lechias, that are of an exceeding gallant tast, neuer hurteth any body, although they shoulde eate a great number of them. Lychees are extensively grown in China, Thailand and the rest of tropical Southeast Asia, the Indian Subcontinent, in South Africa, the Caribbean, Australia and the southeastern United States, they require a tropical climate, frost-free and is not below the temperature of −4 °C. Lychees require a climate with high summer heat and humidity. Growth is best on well-drained acidic soils rich in organic matter and mulch. A wide range of cultivars are available, with early and late maturing forms suited to warmer and cooler climates, respectively, they are grown as an ornamenta
Pyrena
Pyrena or pyrene is the name for the stone within a drupe or drupelet. It consists of a seed surrounded by hard endocarp tissue
Nutmeg
Nutmeg is the seed or ground spice of several species of the genus Myristica. Myristica fragrans is a dark-leaved evergreen tree cultivated for two spices derived from its fruit: nutmeg, from its seed, mace, from the seed covering, it is a commercial source of an essential oil and nutmeg butter. The California nutmeg, Torreya californica, has a seed of similar appearance, but is not related to Myristica fragans, is not used as a spice. If consumed in amounts exceeding its typical use as a spice, nutmeg powder may produce allergic reactions, cause contact dermatitis, or have psychoactive effects. Although used in traditional medicine for treating various disorders, nutmeg has no known medicinal value. Nutmeg is the spice made by grinding the seed of the fragrant nutmeg tree into powder; the spice has a distinctive pungent fragrance and a warm sweet taste. The seeds are dried in the sun over a period of six to eight weeks. During this time the nutmeg shrinks away from its hard seed coat until the kernels rattle in their shells when shaken.
The shell is broken with a wooden club and the nutmegs are picked out. Dried nutmegs are grayish brown ovals with furrowed surfaces; the nutmegs are egg-shaped, about 20.5–30 mm long and 15–18 mm wide, weighing 5–10 g dried. Two other species of genus Myristica with different flavors, M. malabarica and M. argentea, are sometimes used to adulterate nutmeg as a spice. Mace is the spice made from the reddish seed covering of the nutmeg seed, its flavour is more delicate. In the processing of mace, the crimson-colored aril is removed from the nutmeg seed that it envelops and is flattened out and dried for 10 to 14 days, its color changes to pale orange, or tan. Whole dry mace consists of flat pieces—smooth and brittle—about 40 mm long; the most important commercial species is the common, true or fragrant nutmeg, Myristica fragrans, native to the Banda Islands in the Moluccas of Indonesia. It is cultivated on Penang Island in Malaysia, in the Caribbean in Grenada, in Kerala, a state known as Malabar in ancient writings as the hub of spice trading, in southern India.
In the 17th-century work Hortus Botanicus Malabaricus, Hendrik van Rheede records that Indians learned the usage of nutmeg from the Indonesians through ancient trade routes. Nutmeg trees are dioecious plants and asexually. Sexual propagation yields 50 % male seedlings; as there is no reliable method of determining plant sex before flowering in the sixth to eighth year, sexual reproduction bears inconsistent yields, grafting is the preferred method of propagation. Epicotyl grafting, approach grafting, patch budding have proved successful, with epicotyl grafting being the most adopted standard. Air layering is an alternative though not preferred method because of its low success rate; the first harvest of nutmeg trees takes place seven to nine years after planting, the trees reach full production after twenty years. Nutmeg and mace have similar sensory qualities, with nutmeg having a sweeter and mace a more delicate flavour. Mace is preferred in light dishes for the bright orange, saffron-like hue it imparts.
Nutmeg is used for flavouring many dishes, nowadays is found in Western supermarkets in ground or grated form. Whole nutmeg can be ground at home using a grater designed for nutmeg. In Indonesian cuisine, nutmeg is used in various dishes in many spicy soups, such as some variant of soto, oxtail soup, sup iga and sup kambing, it is used in gravy for meat dishes, such as semur beef stew, ribs with tomato, European derived dishes such as bistik and bistik lidah. In Indian cuisine, nutmeg is used in many sweet, as well as savoury, dishes. In Kerala Malabar region, grated nutmeg is used in meat preparations and sparingly added to desserts for the flavour, it may be used in small quantities in garam masala. Ground nutmeg is smoked in India. In traditional European cuisine and mace are used in potato dishes and in processed meat products, it is commonly used in rice pudding. In Dutch cuisine, nutmeg is added to vegetables such as Brussels sprouts and string beans. Nutmeg is a traditional ingredient in mulled cider, mulled wine, eggnog.
In Scotland and nutmeg are both ingredients in haggis. In Italian cuisine, nutmeg is used as part of the stuffing for many regional meat-filled dumplings like tortellini, as well as for the traditional meatloaf. Nutmeg is a common spice for pumpkin pie and in recipes for other winter squashes, such as baked acorn squash. In the Caribbean, nutmeg is used in drinks, such as the Bushwacker and Barbados rum punch, it is a sprinkle on top of the drink. The pericarp is used to make jam, or is finely sliced, cooked with sugar, crystallised to make a fragrant candy. Sliced nutmeg fruit flesh is made as manisan, either wet, seasoned in sugary syrup liquid, or dry coated with sugar, a dessert called manisan pala in Indonesia. In Penang cuisine, dried, sh
Hilum (biology)
In botany, a hilum is a scar or mark left on a seed coat by the former attachment to the ovary wall or to the funiculus. On a bean seed, the hilum is called the "eye". For some species of fungus, the hilum is the microscopic indentation left on a spore when it separates from the sterigma of the basidium. A hilum can be a nucleus of a starch grain; the adjectival form hilar denotes the presence of such a mark, can be used as a distinguishing characteristic of a seed or spore
Fruit anatomy
Fruit anatomy is the plant anatomy of the internal structure of fruit. Fruits are ovaries of one or more flowers. In fleshy fruits, the outer layer is the pericarp, the tissue that develops from the ovary wall of the flower and surrounds the seeds, but in some pericarp fruits, the edible portion is not derived from the ovary. For example, in the fruit of the ackee tree the edible portion is an aril, in the pineapple several tissues from the flower and stem are involved; the outer covering of a seed is tough. Fruits are found in three main anatomical categories: simple fruits, aggregate fruits, multiple fruits. Aggregate fruits contain many ovaries or fruitlets. Examples include blackberries. Multiple fruits are formed from the fused ovaries of multiple flowers or inflorescence. An example of multiple fruits are the fig and the pineapple. Simple fruit may contain one or many seeds, they can be either dry. In fleshy fruit, during development, the pericarp and other accessory structures become the fleshy portion of the fruit.
The types of fleshy fruits are berries and drupes. In berries, the entire pericarp is fleshy but this excludes the exocarp which acts as more as a skin. There are berries that are known as pepo, a type of berry with an inseparable rind, or hesperidium, which has a separable rind. An example of a pepo is the cucumber and a lemon would be an example of a hesperidium; the fleshy portion of the pomes is developed from the floral tube and like the berry most of the pericarp is fleshy but the endocarp is cartilaginous, an apple is an example of a pome. Lastly, drupes are known for being one seeded with a fleshy mesocarp, an example of this would be the peach. However, there are fruits were the fleshy portion is developed from tissues that are not the ovary, such as in the strawberry; the edible part of the strawberry is formed from the receptacle of the flower. Due, to this difference the strawberry is known as an accessory fruit. There is a shared method of seed dispersal within fleshy fruits; these fruits depend on animals to eat the fruits and disperse the seeds in order for their populations to survive.
Dry fruits develop from the ovary but unlike the fleshy fruits they do not depend on the mesocarp but the endocarp for seed dispersal. Dry fruits depend more like wind and water. Dry fruits' seeds can perform pod shattering, which involve the seed being ejected from the seed coat by shattering it; some dry fruits are able to perform wisteria, an extreme case where there is an explosion of the pod, resulting the seed to be dispersed over long distances. Like fleshy fruits, dry fruits can depend on animals to spread their seeds by adhering to animal's fur and skin, this is known as epizoochory. Types of dry fruits include achenes, follicles or nuts. Dry fruits can be separated into dehiscent and indehiscent fruits. Dry dehiscent fruits are described as a fruit where the pod has an increase in internal tension to allow seeds to be released; these include the sweet pea, alfalfa, mustard and poppy. Dry indehiscent fruit differ in that they do not have this mechanism and depend on physical forces. Examples of species indehiscent fruit are sunflower seeds and dandelions.
There is a wide variety in the structures of fruit across the different species of plants. Evolution has selected for certain traits in plants; this diversity arose through the selection of advantageous methods for seed protection and dispersal in different environments. It is known. A study looking at the Rubiaceae family found that within the family, fleshy fruits had evolved independently at least 12 times; this means that fleshy fruits were not passed on to following generations but that this form of fruit was selected for in different species. This may imply that fleshy fruit is a favorable and beneficial trait because not only does it disperse the seeds, but it protects them. There is a variety of dispersal methods that are used by different plants; the origins of these modes of dispersal have been found to be a more recent evolutionary change. Of the methods of dispersal, the plants that use animals have not changed in many ways from the original trait. Due to this, it may be assumed that animal dispersal is an efficient form of dispersal, however there has been no evidence that it increases dispersal distances.
Therefore, the question remains. It has been found, that simple changes within developmental regulatory genes can cause large alterations within the anatomical structure of the fruit. Without knowing the mechanism involved in the biodiversity of fruit, it is clear that this diversity is important to the continuation of plant populations. In berries and drupes, the pericarp forms the edible tissue around the seeds. In other fruits such as Citrus stone fruits only some layers of the pericarp are eaten. In accessory fruits, other tissues develop into the edible portion of the fruit instead, for example the receptacle of the flower in strawberries. In fleshy fruits, the pericarp is made up of three distinct layers: the epicarp, the outermost layer. In a citrus fruit, the epicarp and mesocarp make up the peel. In dry fruits, the layers of the pericarp are not cle
Ovule
In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: The integument, forming its outer layer, the nucellus, the female gametophyte in its center; the female gametophyte — termed a megagametophyte— is called the embryo sac in angiosperms. The megagametophyte produces an egg cell for the purpose of fertilization. In flowering plants, the ovule is located inside the portion of the flower called the gynoecium; the ovary of the gynoecium produces one or more ovules and becomes the fruit wall. Ovules are attached to the placenta in the ovary through a stalk-like structure known as a funiculus. Different patterns of ovule attachment, or placentation, can be found among plant species, these include: Apical placentation: The placenta is at the apex of the ovary. Simple or compound ovary. Axile placentation: The ovary is divided into radial segments, with placentas in separate locules. Ventral sutures of carpels meet at the centre of the ovary.
Placentae are along fused margins of carpels. Two or more carpels. Basal placentation: The placenta is at the base of the ovary on a protrusion of the thalamus. Simple or compound carpel, unilocular ovary. Free-central placentation: Derived from axile as partitions are absorbed, leaving ovules at the central axis. Compound unilocular ovary. Marginal placentation: Simplest type. There is only one elongated placenta on one side of the ovary, as ovules are attached at the fusion line of the carpel's margins; this is conspicuous in legumes. Simple carpel, unilocular ovary. Parietal placentation: Placentae on inner ovary wall within a non-sectioned ovary, corresponding to fused carpel margins. Two or more carpels, unilocular ovary. Superficial: Similar to axile, but placentae are on inner surfaces of multilocular ovary Ovule orientation may be anatropous, such that when inverted the micropyle faces the placenta, campylotropous, or orthotropous. In gymnosperms such as conifers, ovules are borne on the surface of an ovuliferous scale within an ovulate cone.
In some extinct plants and ovules were borne on the surface of leaves. In other extinct taxa, a cupule surrounds the ovule; the ovule appears to be a megasporangium with integuments surrounding it. Ovules are composed of diploid maternal tissue, which includes a megasporocyte. Megaspores remain inside the ovule and divide by mitosis to produce the haploid female gametophyte or megagametophyte, which remains inside the ovule; the remnants of the megasporangium tissue surround the megagametophyte. Megagametophytes produce archegonia. After fertilization, the ovule contains a diploid zygote and after cell division begins, an embryo of the next sporophyte generation. In flowering plants, a second sperm nucleus fuses with other nuclei in the megagametophyte forming a polyploid endosperm tissue, which serves as nourishment for the young sporophyte. An integument is a protective cell layer surrounding the ovule. Gymnosperms have one integument while angiosperms have two integuments; the evolutionary origin of the inner integument has been proposed to be by enclosure of a megasporangium by sterile branches.
Elkinsia, a preovulate taxon, has a lobed structure fused to the lower third of the megasporangium, with the lobes extending upwards in a ring around the megasporangium. This might, through fusion between lobes and between the structure and the megasporangium, have produced an integument; the origin of the second or outer integument has been an area of active contention for some time. The cupules of some extinct taxa have been suggested as the origin of the outer integument. A few angiosperms produce vascular tissue in the outer integument, the orientation of which suggests that the outer surface is morphologically abaxial; this suggests that cupules of the kind produced by the Caytoniales or Glossopteridales may have evolved into the outer integument of angiosperms. The integuments develop into the seed coat; the integuments do not enclose the nucellus but retain an opening at the apex referred to as the micropyle. The micropyle opening allows the pollen to enter the ovule for fertilization. In gymnosperms, the pollen is drawn into the ovule on a drop of fluid that exudes out of the micropyle, the so-called pollination drop mechanism.
Subsequently, the micropyle closes. In angiosperms, only a pollen tube enters the micropyle. During germination, the seedling's radicle emerges through the micropyle. Located opposite from the micropyle is the chalaza. Nutrients from the plant travel through the phloem of the vascular system to the funiculus and outer integument and from there apoplastically and symplastically through the chalaza to the nucellus inside the ovule. In chalazogamous plants, the pollen tubes enter the ovule through the chalaza instead of the micropyle opening; the nucellus is part of the inner structure of the ovule, forming a layer of dipl
Gymnosperm
The gymnosperms known as Acrogymnospermae, are a group of seed-producing plants that includes conifers, cycads and gnetophytes. The term "gymnosperm" comes from the Greek composite word γυμνόσπερμος, meaning "naked seeds"; the name is based on the unenclosed condition of their seeds. The non-encased condition of their seeds stands in contrast to the seeds and ovules of flowering plants, which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, which are modified to form cones, or solitary as in Yew, Ginkgo; the gymnosperms and angiosperms together compose the spermatophytes or seed plants. The gymnosperms are divided into six phyla. Organisms that belong to the Cycadophyta, Ginkgophyta and Pinophyta phyla are still in existence while those in the Pteridospermales and Cordaitales phyla are now extinct. By far the largest group of living gymnosperms are the conifers, followed by cycads and Ginkgo biloba. Roots in some genera have fungal association with roots in the form of mycorrhiza, while in some others small specialised roots called coralloid roots are associated with nitrogen-fixing cyanobacteria.
The current formal classification of the living gymnosperms is the "Acrogymnospermae", which form a monophyletic group within the spermatophytes. The wider "Gymnospermae" group is thought to be paraphyletic; the fossil record of gymnosperms includes many distinctive taxa that do not belong to the four modern groups, including seed-bearing trees that have a somewhat fern-like vegetative morphology. When fossil gymnosperms such as these and the Bennettitales and Caytonia are considered, it is clear that angiosperms are nested within a larger gymnospermae clade, although which group of gymnosperms is their closest relative remains unclear; the extant gymnosperms include 12 main families and 83 genera which contain more than 1000 known species. Subclass Cycadidae Order Cycadales Family Cycadaceae: Cycas Family Zamiaceae: Dioon, Macrozamia, Encephalartos, Ceratozamia, Zamia. Subclass Ginkgoidae Order Ginkgoales Family Ginkgoaceae: GinkgoSubclass Gnetidae Order Welwitschiales Family Welwitschiaceae: Welwitschia Order Gnetales Family Gnetaceae: Gnetum Order Ephedrales Family Ephedraceae: EphedraSubclass Pinidae Order Pinales Family Pinaceae: Cedrus, Cathaya, Pseudotsuga, Pseudolarix, Nothotsuga, Abies Order Araucariales Family Araucariaceae: Araucaria, Agathis Family Podocarpaceae: Phyllocladus, Prumnopitys, Halocarpus, Lagarostrobos, Saxegothaea, Pherosphaera, Dacrycarpus, Falcatifolium, Nageia, Podocarpus Order Cupressales Family Sciadopityaceae: Sciadopitys Family Cupressaceae: Cunninghamia, Athrotaxis, Sequoia, Cryptomeria, Taxodium, Austrocedrus, Pilgerodendron, Diselma, Callitris, Thuja, Chamaecyparis, Cupressus, Xanthocyparis, Tetraclinis, Microbiota Family Taxaceae: Austrotaxus, Taxus, Amentotaxus, Torreya There are over 1000 living species of gymnosperm.
It is accepted that the gymnosperms originated in the late Carboniferous period, replacing the lycopsid rainforests of the tropical region. This appears to have been the result of a whole genome duplication event around 319 million years ago. Early characteristics of seed plants were evident in fossil progymnosperms of the late Devonian period around 383 million years ago, it has been suggested that during the mid-Mesozoic era, pollination of some extinct groups of gymnosperms was by extinct species of scorpionflies that had specialized proboscis for feeding on pollination drops. The scorpionflies engaged in pollination mutualisms with gymnosperms, long before the similar and independent coevolution of nectar-feeding insects on angiosperms. Evidence has been found that mid-Mesozoic gymnosperms were pollinated by Kalligrammatid lacewings, a now-extinct genus with members which resembled the modern butterflies that arose far later. Conifers are by far the most abundant extant group of gymnosperms with six to eight families, with a total of 65-70 genera and 600-630 species.
Conifers most are evergreens. The leaves of many conifers are long and needle-like, other species, including most Cupressaceae and some Podocarpaceae, have flat, triangular scale-like leaves. Agathis in Araucariaceae and Nageia in Podocarpaceae have flat strap-shaped leaves. Cycads are the next most abundant group of gymnosperms, with two or three families, 11 genera, 338 species. A majority of cycads are native to tropical climates and are most abundantly found in regions near the equator; the other extant groups are one species of Ginkgo. Gymnosperms have major economic uses. Pine, fir and cedar are all examples of conifers that are used for lumber, paper production, resin; some other common uses for gymnosperms are soap, nail polish, food and perfumes. Gymnosperms, like all vascular plants, have a sporophyte-dominant life cycle, which means they spend most of their life cycle with diploid cells, while
