一、莎草类发生概况莎草,俗称三棱草、香附子,是植物界的一大类群,属被子植物门、单子叶植物纲、莎草目、莎草科。世界有70多个属,5000多种,主要分布在温带和热带地区。中国有30多个属,600余种,危害农作物最重的是莎草属,如香附子、碎米莎草、扁穗莎草、异型莎草等。莎草最适宜在山坡荒地、水生地、潮湿沼泽地生长,现已广泛蔓延,分布全国各地的非耕田、草坪、水田和多种旱田作物。因适应性强、分布广、繁殖快、危害重、防除难,被列为世界恶性杂草之一。莎草类具明显突出外部症状:地上部有细长的叶和较高的茎,叶丛生于茎基部,茎三棱形,不分节,外表光滑,因种类不同,茎高在15~90厘米不等。地下根呈球茎连接,匍匐延长,球茎产生根茎,根茎再产生新的球茎,新球茎萌生幼芽,一株接一株,连绵不断,在一个生长季节内几十倍繁殖。球茎多为圆型或纺锤型,外表有纹状,呈黑色或黑褐色,内心白色。球茎 First, the occurrence of sedge class Sesame, commonly known as Sanxiancao, Cyperus rotundus, is a large group of plant kingdom, is an angiosperm door, monocotyledons, Sage, Cyperaceae. The world has more than 70 genera, more than 5000 species, mainly in temperate and tropical regions. There are more than 30 genera and 600 species in China. The hardest crop is the genus Cyperus, such as Cyperus rotundus, Brassica oleracea, Cuscutacea, Shaped sedges. Sedge grass is most suitable for growing on hillside wasteland, aquatic land and wet marshes. It has spread widely and distributed non-farmland, lawn, paddy field and various dryland crops all over the country. Because of its adaptability, wide distribution, rapid propagation, endangering the heavy, controlling difficult, it is listed as one of the world’s malignant weeds. Cyperaceae with obvious prominent external symptoms: the upper part of the slender leaves and tall stems, leaves were born in the base of the stem, stems triangular, regardless of section, the appearance of smooth, due to the different types of stem height 15 ~ 90 Centimeter range. Roots were underground bulbous connection, creeping extended corms produce rhizomes, rhizomes produce new bulbs, new bulbous sprouting buds, one after another, continuous, in a growing season within a few times breeding. Corolla mostly round or spindle type, the appearance of a pattern, was black or dark brown, white heart. bulb