草莓的说明文有的发来

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/09 12:50:31
草莓的说明文有的发来

草莓的说明文有的发来
草莓的说明文
有的发来

草莓的说明文有的发来
草莓,又叫洋莓,红莓,原产欧洲,本世纪初传入我国而风靡华夏.草莓外观呈心形,其色鲜艳粉红,果肉多汁,酸甜适口,芳香宜人,营养丰富,故有“水果皇后”之美誉.
据分析,草莓富含氨基酸、果糖、蔗糖、葡萄糖、柠檬酸、苹果酸、果胶、胡萝卜素、维生素B1、B2、烟酸及矿物质钙、镁、磷、铁等,这些营养素对生长发育有很好的促进作用,对老人、儿童大有裨益.国外学者研究发现,草莓中的有效成分,可抑制癌肿的生长.每百克草莓含维生素C50-100毫克,比苹果、葡萄高10倍以上.科学研究业已证实,维生素C能消除细胞间的松驰与紧张状态,使脑细胞结构坚固,皮肤细腻有弹性,对脑和智力发育有重要影响.饭后吃一些草莓,可分解食物脂肪,有利消化.
草莓的食法比较多,常见的是将草莓冲洗干净,直接食用,或将洗净的草莓拌以白糖或甜牛奶食用,风味独特,别具一格.随着食品工业的发展,草莓已制成各种果酱、果冻、果脯、糖水罐头、果汁等,市场前景十分可观.
草莓入药亦堪称上品,中医认为,草莓性味甘、凉,入脾、胃、肺经,有润肺生津,健脾和胃,利尿消肿,解热祛暑之功,适用于肺热咳嗽,食欲不振,小便短少,暑热烦渴等.草莓中丰富的维生素C除了可以预防坏血病以外,对动脉硬化、冠心病、心绞痛、脑溢血、高血压、高血脂等,都有积极的预防作用.草莓中含有的果胶及纤维素,可促进胃肠蠕动,改善便秘,预防痔疮、肠癌的发生.草莓中含有的胺类物质,对白血病,再生障碍性贫血有一定疗效.
草莓属(Fragaria)
蔷薇科蔷薇亚科的1属.矮小多年生草本,有短而粗壮根茎,紧贴地面上,由叶腋生出细长匍匐茎,茎上有长节间,节上生根与叶,供繁殖用.叶互生成簇,叶柄通常较叶片长,叶为羽状.3或5小叶,托叶鞘状,附着在叶柄基部,与叶同时长大.花常成总状或伞房状花序,生于直立的花葶上,两性或单性,花托突出成圆锥状,萼片5,有5片副萼,在果时宿存;花瓣5,白色,着生在花托边缘上,雄蕊多数,有时少数或不存;心皮多数,着生在花托上,每1心皮有1侧生花柱与1胚珠.花托在开花后增大成为肉质,其上着生多数种子状瘦果,成为聚合果或称多心皮果.草莓属约有50种,分布亚洲、欧洲和美洲.中国产9种,其中一种系引种栽培.
草莓属的野生种有:①野草莓,又名欧洲草莓,分布于北温带.在中国产于东北、西北、西南,生长于山坡、草地、林边.②东方草莓,产中国东北、华北、西北;朝鲜、蒙古以及苏联远东地区也有分布.③黄毛草莓,产华西、西南以至台湾;尼泊尔、锡金、印度、越南也有分布.④西南草莓,分布西南、西北至西藏.⑤五叶草莓,产西北至四川.⑥纤细草莓,产西北、华西至西藏.⑦西藏草莓,产西藏,分布锡金、巴基斯坦、阿富汗,以及克什米尔地区.⑧裂萼草莓,产西藏.引种栽培者名为凤梨草莓(F.xananassa),系园艺杂种,由智利草莓和威州草莓杂交成八倍体.一般野生草莓多为二倍体(2n=14)或四倍体(2n=28),杂交后成为八倍体(2n=56).
草莓是全世界温带和亚热带广泛栽培的草本浆果之一,主要产于欧洲各国和北美各地.中国栽培历史较短,目前产量虽不大,但中国草莓资源丰富,分布普遍,且草莓植株矮小,繁殖栽培方法简易,开始结果年龄较早,移植后第一年春季即能开花结果.第二年即可丰产.果实香嫩多汁,含有极丰富的营养物质.除生食外,适宜冻藏或加工,制成果酱、果汁、果酒、果糕等.
编辑词条
开放分类:
植物、生物学、蔷薇亚科

strawberry
The strawberry (Fragaria) is a genus of plants in the family Rosaceae, and the fruit of these plants. There are more than 20 named species and many hybrids and cultivars. The most comm...

全部展开

strawberry
The strawberry (Fragaria) is a genus of plants in the family Rosaceae, and the fruit of these plants. There are more than 20 named species and many hybrids and cultivars. The most common strawberries grown commercially are cultivars of the Garden strawberry, a Fragaria × ananassa hybrid. Strawberries are a valuable source of vitamin C.
Morphology
The strawberry is an accessory fruit; that is, the fleshy part is derived not from the ovaries (which are the "seeds", actually achenes) but from the peg at the bottom of the hypanthium that held the ovaries. So from a technical standpoint, the seeds are the actual fruits of the plant, and the flesh of the strawberry is a vegetable. It is greenish-white as it develops and in most species turns red when ripe.
The rosette growth of the plants are a well-known characteristic. Most species send out long slender runners that produce a new bud at the extremity. The leaves typically have three leaflets, but the number of leaflets may be five or one.
While the flower has the typical rosaceous structure, the fruit is very peculiar, but it may be understood by the contrast it presents with the rose hip of the rose. In a rose the top of the flower-stalk expands as it grows into a vase-shaped cavity, the hip, within which are concealed the true fruits or seed-vessels. In the rose the extremity of the floral axis is concave and bears the carpels in its interior. In the strawberry, the floral axis, instead of being concave, swells out into a fleshy, dome-shaped or flattened mass in which the carpels or true fruits, commonly called pips or seeds, are more or less embedded but never wholly concealed. A ripe strawberry in fact may be aptly compared to the fruit of a rose turned inside out.
Strawberries are now out of season.
Classification
There are more than 20 Fragaria species worldwide. Key to the classification of strawberry species is recognizing that they vary in the number of chromosomes. There are seven basic types of chromosomes that they all have in common. However, they exhibit different polyploidy. Some species are diploid, having two sets of the seven chromosomes (14 chromosomes total). Others are tetraploid (four sets, 28 chromosomes total), hexaploid (six sets, 42 chromosomes total), octoploid (eight sets, 56 chromosomes total), or decaploid (ten sets, 70 chromosomes total).
As a rough rule (with exceptions), strawberry species with more chromosomes tend to be more robust and produce larger plants with larger berries (Darrow).
Etymology
The name is derived from Old English streawberige which is a compound of streaw meaning "straw" and berige meaning "berry". The reason for this is unclear. It may derive from the strawlike appearance of the runners, or from an obsolete denotation of straw, meaning "chaff", referring to the scattered appearance of the achenes.
Interestingly, in other Germanic countries there is a tradition of collecting wild strawberries by threading them on straws. In those countries people find straw-berry to be an easy word to learn considering their association with straws.
There is an alternative theory that the name derives from the Anglo-Saxon verb for "strew" (meaning to spread around) which was streabergen (Strea means "strew" and Bergen means "berry" or "fruit") and thence to streberie, straiberie, strauberie, straubery, strauberry, and finally, "strawberry", the word which we use today. The name might have come from the fact that the fruit and various runners appear "strewn" along the ground.
Popular etymology has it that it comes from gardeners' practice of mulching strawberries with straw to protect the fruits from rot (a pseudoetymology that can be found in non-linguistic sources such as the Old Farmer's Almanac 2005). However, there is no evidence that the Anglo-Saxons ever grew strawberries, and even less that they knew of this practice.

收起