龍爪桑(sang)(Morus alba 'Tortuosa')是桑(sang)科(ke)、桑(sang)屬桑(sang)樹(shu)的栽(zai)培變種,喬(qiao)木或為灌(guan)木,株高可達3米,樹(shu)冠開張。枝條圓柱形,呈(cheng)S形扭曲。葉互(hu)生,葉(xie)片闊(kuo)卵(luan)(luan)形(xing)(xing)(xing)(xing),先端尖(jian),鋸齒緣(yuan)。樹皮厚,灰色,具(ju)不規(gui)則淺縱裂;冬(dong)芽紅(hong)褐色,卵(luan)(luan)形(xing)(xing)(xing)(xing),芽鱗(lin)覆瓦(wa)狀(zhuang)排列,灰褐色,有(you)細(xi)毛(mao)(mao);小枝有(you)細(xi)毛(mao)(mao)。葉卵(luan)(luan)形(xing)(xing)(xing)(xing)或(huo)(huo)廣卵(luan)(luan)形(xing)(xing)(xing)(xing),先端急(ji)尖(jian)、漸(jian)尖(jian)或(huo)(huo)圓(yuan)鈍,邊(bian)緣(yuan)鋸齒粗鈍,葉柄具(ju)柔毛(mao)(mao);托葉披針形(xing)(xing)(xing)(xing),早(zao)落,外面密被(bei)細(xi)硬毛(mao)(mao)。花(hua)(hua)單性,腋生或(huo)(huo)生于(yu)芽鱗(lin)腋內,與葉同時(shi)生出;雄(xiong)花(hua)(hua)序下垂,密被(bei)白色柔毛(mao)(mao),雄(xiong)花(hua)(hua)。花(hua)(hua)被(bei)片寬橢(tuo)圓(yuan)形(xing)(xing)(xing)(xing),淡綠色。花(hua)(hua)絲在芽時(shi)內折,球形(xing)(xing)(xing)(xing)至(zhi)腎形(xing)(xing)(xing)(xing),縱裂;雌雄(xiong)異(yi)株,雌花(hua)(hua)序直立。果實成熟時(shi)紫(zi)黑色。被(bei)毛(mao)(mao),雌花(hua)(hua)無(wu)梗,花(hua)(hua)被(bei)片倒卵(luan)(luan)形(xing)(xing)(xing)(xing),頂(ding)端圓(yuan)鈍,外面和邊(bian)緣(yuan)被(bei)毛(mao)(mao),無(wu)花(hua)(hua)柱,聚花(hua)(hua)果卵(luan)(luan)狀(zhuang)橢(tuo)圓(yuan)形(xing)(xing)(xing)(xing),成熟時(shi)紅(hong)色或(huo)(huo)暗紫(zi)色。5月開花(hua)(hua),6月中旬結果。
原產中(zhong)國中(zhong)北(bei)部,分布遼寧以南地區。陽(yang)性植(zhi)物。性喜溫(wen)暖(nuan)至高溫(wen)、濕(shi)潤(run)、向陽(yang)之(zhi)地,生性強健,成長快(kuai)速,耐(nai)(nai)熱也耐(nai)(nai)寒,耐(nai)(nai)旱、耐(nai)(nai)濕(shi)。
龍(long)爪(zhua)(zhua)桑果實(shi)味(wei)道鮮美,可用(yong)(yong)于生食(shi)(shi)及釀酒等。葉片大產葉量(liang)高(gao),可用(yong)(yong)于養蠶(can),因此.龍(long)爪(zhua)(zhua)桑是集觀賞、鮮食(shi)(shi)、加工、養蠶(can)多功能于一體的優良桑樹變種,具(ju)有一定(ding)的栽植應用(yong)(yong)前(qian)景。
喬(qiao)木或為灌木(mu),株高可達3米(mi),冠幅2.0-2.5米(mi)。胸徑可達50厘米,樹(shu)冠開張。枝條(tiao)圓(yuan)柱形(xing),呈S形(xing)扭(niu)曲(qu)。葉(xie)(xie)互(hu)生,葉(xie)(xie)片20x12厘米,闊(kuo)卵(luan)形(xing),先端尖(jian),鋸齒緣。樹皮厚,灰色,具不規則淺縱裂;冬(dong)芽紅(hong)褐色,卵形,芽(ya)鱗覆瓦狀(zhuang)排(pai)列,灰褐色,有(you)細毛;小枝有(you)細毛。葉(xie)(xie)卵(luan)形(xing)(xing)或(huo)廣卵(luan)形(xing)(xing),長(chang)5-15厘(li)米,寬5-12厘(li)米,先端(duan)急尖(jian)、漸尖(jian)或(huo)圓鈍,基(ji)部圓形(xing)(xing)至(zhi)淺心形(xing)(xing),邊緣鋸齒(chi)粗鈍,有(you)時葉(xie)(xie)為各種分裂,表面(mian)(mian)鮮綠色,無毛,背面(mian)(mian)沿脈有(you)疏毛,脈腋有(you)簇毛;葉(xie)(xie)柄長(chang)1.5-5.5厘(li)米,具柔毛;托葉(xie)(xie)披針形(xing)(xing),早(zao)落,外面(mian)(mian)密被細硬(ying)毛。
花(hua)(hua)(hua)(hua)(hua)單性,腋生(sheng)(sheng)(sheng)或生(sheng)(sheng)(sheng)于(yu)芽鱗腋內(nei),與葉同時(shi)生(sheng)(sheng)(sheng)出;雄(xiong)花(hua)(hua)(hua)(hua)(hua)序(xu)下(xia)垂(chui),長2-3.5厘(li)米(mi)(mi),密被(bei)(bei)(bei)白色柔毛(mao),雄(xiong)花(hua)(hua)(hua)(hua)(hua)。花(hua)(hua)(hua)(hua)(hua)被(bei)(bei)(bei)片(pian)寬橢(tuo)圓(yuan)形(xing),淡綠色。花(hua)(hua)(hua)(hua)(hua)絲在芽時(shi)內(nei)折,花(hua)(hua)(hua)(hua)(hua)藥2室,球(qiu)形(xing)至腎(shen)形(xing),縱裂;雌雄(xiong)異(yi)株,雄(xiong)花(hua)(hua)(hua)(hua)(hua)序(xu)下(xia)垂(chui),雌花(hua)(hua)(hua)(hua)(hua)序(xu)直立(li)。果實成熟(shu)(shu)時(shi)紫黑色。雌花(hua)(hua)(hua)(hua)(hua)序(xu)長1-2厘(li)米(mi)(mi),被(bei)(bei)(bei)毛(mao),總(zong)花(hua)(hua)(hua)(hua)(hua)梗長5-10毫米(mi)(mi)被(bei)(bei)(bei)柔毛(mao),雌花(hua)(hua)(hua)(hua)(hua)無(wu)梗,花(hua)(hua)(hua)(hua)(hua)被(bei)(bei)(bei)片(pian)倒卵(luan)形(xing),頂(ding)端(duan)圓(yuan)鈍,外面和邊(bian)緣(yuan)被(bei)(bei)(bei)毛(mao),兩側緊(jin)抱子房,無(wu)花(hua)(hua)(hua)(hua)(hua)柱(zhu),柱(zhu)頭2裂,內(nei)面有乳頭狀(zhuang)突起。聚花(hua)(hua)(hua)(hua)(hua)果卵(luan)狀(zhuang)橢(tuo)圓(yuan)形(xing),長1-2.5厘(li)米(mi)(mi),成熟(shu)(shu)時(shi)紅色或暗(an)紫色。花(hua)(hua)(hua)(hua)(hua)期5月,果期6月中旬。
原產中國中北部,分布遼寧以(yi)南地區。陽性植物(wu)。性喜溫暖至高溫、濕潤、向陽之地(di),生長(chang)適宜溫度18-30℃,日照70-100%。生性強健,成長(chang)快速,耐(nai)熱也耐寒,耐旱、耐濕。
播(bo)種育(yu)苗:據近年(nian)生(sheng)產實踐觀(guan)察,龍(long)爪桑播種(zhong)苗的葉片、果實性(xing)狀無變(bian)化,枝條彎曲程度稍小,但觀(guan)賞性(xing)不減(jian),而其適應性(xing)明(ming)顯(xian)提高。因此.可以用播種(zhong)法繁殖龍(long)爪桑苗木果實采集與(yu)種(zhong)子(zi)處理(li):6月中(zhong)下旬(xun)采集已(yi)充分(fen)(fen)成(cheng)熟的紫黑色漿果,攤于水泥地面,輕搓踏果實,使(shi)果肉(rou)與(yu)種(zhong)子(zi)分(fen)(fen)離。裝人桶中(zhong),多次加水漂(piao)投(tou),去果肉(rou)和癟粒,撈出(chu)種(zhong)子(zi),存(cun)于陰涼處,不可晾干或曬干,等待播種。
做床(chuang):6月(yue)上(shang)中旬(xun)采(cai)種(zhong)的(de)同時(shi)或前(qian)2天(tian),選平(ping)坦(tan)砂壤至中壤地塊,做1.2寬、0.10米(mi)(mi)高、10-25米(mi)(mi)長的(de)床(chuang)。床(chuang)表均(jun)勻(yun)撒細碎(sui)農家肥料,每10米(mi)(mi)用量50千(qian)克(ke)。翻土15厘米(mi)(mi)深,使糞與土混合。打碎(sui)土塊,整(zheng)平(ping)床(chuang)面.四(si)周床(chuang)緣(yuan)用鍬拍實。
播(bo)種:橫床(chuang)(chuang)向開2厘(li)米深(shen)溝(gou),溝(gou)距20-25厘(li)米,將(jiang)已(yi)混5倍沙子(zi)的種子(zi)撒人溝(gou)內(nei),覆(fu)原床(chuang)(chuang)土(tu)1厘(li)米厚,播(bo)種量20-25克/10平方米,播(bo)種后(hou)向床(chuang)(chuang)表覆(fu)蓋0.5厘(li)米厚的稻殼(ke)或1厘(li)米厚的細碎樹葉向覆(fu)蓋物上噴20-25℃的水,每3-5天一次,約(yue)15天出苗。
龍爪桑苗(miao)(miao)根系發達,枝條木(mu)質程度較高,越(yue)(yue)冬前(qian)一般不必進(jin)行越(yue)(yue)冬埋土防(fang)寒、防(fang)旱(han),特殊寒冷地區應簡(jian)易防(fang)寒出苗(miao)(miao)后的生長季保持土壤不干(gan)即可及時多(duo)次拔掉或鏟除雜草7月下旬至8月初(chu)向床(chuang)面均勻撒磷酸二(er)銨肥料,用量為10千(qian)克/667平方(fang)米,施(shi)肥后若無降雨,應噴水,以(yi)防燒苗。當年(nian)采(cai)種并播(bo)種長出的苗,到秋(qiu)末高(gao)度可(ke)達20-35厘(li)米,地徑達0.2-0.3厘(li)米,產苗量約8萬株/667平方米。
龍爪桑(sang)生長季遇食葉害蟲為害,可噴灑25%溴(xiu)氰菊酯(zhi)2000倍液。
龍(long)爪桑果實(shi)味道鮮美,可用(yong)于生食及(ji)釀酒等。葉(xie)片大產葉(xie)量(liang)高,可用(yong)于養蠶,因此.龍(long)爪桑是集觀賞、鮮食、加工、養蠶多功能于一體的優良桑樹變(bian)種,具有一定的栽植應用(yong)前景。