白瓜又叫稍瓜、生瓜、越瓜、酥瓜、田瓜等,屬葫蘆科。白瓜外皮光滑,有縱(zong)長線(xian)條,汁多、質脆。可(ke)以(yi)生吃,亦可(ke)做(zuo)菜、湯等。
主(zhu)要分布于亞洲熱帶(dai)、亞熱帶(dai)地區,澳大利(li)亞東(dong)部(bu),馬(ma)達加斯加;我國各地栽培。
一年生(sheng)蔓生(sheng)草(cao)本;莖密(mi)被黃褐色毛(mao)(mao)。卷(juan)須(xu)常分2-3叉;葉柄粗壯;葉片腎狀近圓形(xing),寬10-30厘米,基部灣缺深,5-7淺裂(lie)或有(you)時中裂(lie),邊緣有(you)小鋸齒,兩面生(sheng)有(you)硬毛(mao)(mao)。
雌(ci)雄同株;花單生(sheng),花梗(geng)被硬(ying)(ying)毛;花萼裂(lie)(lie)片(pian)有鋸(ju)齒,反折(zhe);花冠黃色,輻(fu)狀(zhuang),裂(lie)(lie)片(pian)寬(kuan)倒卵形(xing),長(chang)3-6厘米;雄蕊3,分生(sheng),藥室多(duo)回(hui)折(zhe)曲;子(zi)房卵形(xing)或圓筒形(xing),密生(sheng)黃褐色硬(ying)(ying)毛,柱(zhu)頭3, 2裂(lie)(lie)。果實長(chang)圓柱(zhu)狀(zhuang)或近球狀(zhuang),大型,有毛和白粉;種子(zi)卵形(xing),白色或淡黃色,壓(ya)扁(bian)狀(zhuang)。
白瓜屬喜(xi)溫(wen)作(zuo)物,耐寒(han)性差(cha),一(yi)般在當(dang)地斷霜后,土溫(wen)15℃和氣溫(wen)20℃以上(shang)的季(ji)節栽培。
白瓜(gua)為(wei)大眾經常(chang)食用的(de)蔬菜,有(you)非常(chang)高的(de)藥用價(jia)值(zhi),白瓜(gua)的(de)營(ying)養成分:每100克(ke)(ke)(ke)白瓜(gua)中含有(you)蛋白質(zhi)0.9克(ke)(ke)(ke),糖2.9克(ke)(ke)(ke),熱量62.7千(qian)焦(jiao),鈣24毫(hao)克(ke)(ke)(ke),磷1l毫(hao)克(ke)(ke)(ke),鐵0.2毫(hao)克(ke)(ke)(ke),胡蘿卜(bu)素(su)0.02毫(hao)克(ke)(ke)(ke),維生素(su)B1 0.02毫(hao)克(ke)(ke)(ke),維生素(su)B2 0.03毫(hao)克(ke)(ke)(ke),尼克(ke)(ke)(ke)酸0.2毫(hao)克(ke)(ke)(ke),維生素(su)白瓜(gua)的(de)功效:白瓜(gua)性味甘、寒,有(you)利小便、解(jie)熱毒的(de)作用,可治(zhi)煩熱口渴,小便不(bu)利等癥。
白瓜(gua)富(fu)含(han)蛋白質(zhi)、礦物質(zhi)和(he)維生素等(deng)物質(zhi),不含(han)脂(zhi)肪,還含(han)有瓜(gua)氨酸、腺嘌呤(ling)、天門冬氨酸等(deng)物質(zhi),且含(han)鈉鹽很(hen)低。
白(bai)(bai)瓜(gua)屬(shu)葫蘆科(ke)甜瓜(gua)屬(shu)一年生蔓生植(zhi)物,近年來,白(bai)(bai)瓜(gua)種(zhong)植(zhi)面(mian)積不斷擴大(da),種(zhong)子需(xu)求量不斷增(zeng)加,但(dan)由于受華南地區特(te)殊的氣候因素制約,白(bai)(bai)瓜(gua)采種(zhong)時常出(chu)現種(zhong)瓜(gua)腐爛(lan)現象,嚴(yan)重(zhong)影(ying)響留種(zhong)效益。
有機白瓜(gua)屬喜溫(wen)(wen)作(zuo)物,耐(nai)寒性差,一般在(zai)當地斷霜(shuang)后(hou),土溫(wen)(wen)15℃和(he)氣溫(wen)(wen)20℃以上的季(ji)節栽(zai)培(pei)。在(zai)廣東,適播(bo)期(qi)為4—8月,春植白瓜(gua)一般在(zai)清明后(hou)直播(bo),播(bo)種(zhong)(zhong)太早,易受凍害(hai),出苗緩慢且(qie)不整(zheng)齊,影響植株中后(hou)期(qi)生長發育和(he)種(zhong)(zhong)子形(xing)成(cheng)。
由于華南地區降雨量大,多(duo)采用高(gao)畦、深排水溝(gou)、覆地膜(或稻草(cao)、蕨類(lei)植(zhi)(zhi)物芒(mang)箕(ji)等)栽培。為提高(gao)種子產量,采種田(tian)應合理密植(zhi)(zhi)。一般采用單(dan)行(xing)植(zhi)(zhi)或雙行(xing)植(zhi)(zhi),單(dan)行(xing)株(zhu)距(ju)18—20cm,行(xing)距(ju)130—150cm;雙行(xing)株(zhu)距(ju)40—60cm,行(xing)距(ju)150—200cm,每穴2—4粒(li),667m2栽3000—3500株(zhu)。
白瓜是雌雄異(yi)花(hua)同株的蟲媒花(hua)植(zhi)物,品種(zhong)間容易發生自然雜交,要(yao)求在采種(zhong)田(tian)周圍1500cm以內無甜瓜屬的其他(ta)品種(zhong)同期開花(hua)。在此隔離條(tiao)件下(xia),可(ke)(ke)完全(quan)由(you)昆蟲自由(you)授粉留(liu)種(zhong)。為了提(ti)高(gao)產量(liang)可(ke)(ke)采用人工輔助(zhu)授粉方(fang)式留(liu)種(zhong)。
人工輔助(zhu)授粉時,在選定的(de)雌(ci)(ci)(ci)花(hua)(hua)(hua)(hua)開(kai)放前l天下(xia)午,用(yong)3cm長的(de)鋁線碼同時分別夾住同一種株上的(de)雌(ci)(ci)(ci)花(hua)(hua)(hua)(hua)和雄花(hua)(hua)(hua)(hua)花(hua)(hua)(hua)(hua)冠(guan),松緊適(shi)度;然后于(yu)開(kai)花(hua)(hua)(hua)(hua)當(dang)日上午8—11時,采集(ji)夾過的(de)雄花(hua)(hua)(hua)(hua),去掉花(hua)(hua)(hua)(hua)瓣,用(yong)雄花(hua)(hua)(hua)(hua)花(hua)(hua)(hua)(hua)藥輕抹(mo)雌(ci)(ci)(ci)花(hua)(hua)(hua)(hua)柱頭后,用(yong)原鋁線碼夾住雌(ci)(ci)(ci)花(hua)(hua)(hua)(hua)花(hua)(hua)(hua)(hua)冠(guan),并(bing)掛牌標記,一般一朵雄花(hua)(hua)(hua)(hua)可授1—2朵雌(ci)(ci)(ci)花(hua)(hua)(hua)(hua)。
為(wei)保證種(zhong)(zhong)(zhong)子純度,必須進行種(zhong)(zhong)(zhong)株及(ji)種(zhong)(zhong)(zhong)瓜的選擇(ze)。首先,在定苗(miao)前(qian),選擇(ze)生長一致、無(wu)病蟲(chong)危害、無(wu)畸形(xing)表(biao)現的幼苗(miao)定苗(miao);其次,在開花坐果時(shi),選生長勢中(zhong)(zhong)等,雌花節位(wei)適中(zhong)(zhong),無(wu)畸形(xing)表(biao)現和無(wu)病蟲(chong)危害的植(zhi)株作(zuo)種(zhong)(zhong)(zhong)株,授粉坐果后(hou),分期選生長正常(chang)的果實作(zuo)種(zhong)(zhong)(zhong)瓜,并掛(gua)牌標記(ji);最(zui)后(hou),在種(zhong)(zhong)(zhong)瓜采(cai)收時(shi)選瓜形(xing)正常(chang)、符合品種(zhong)(zhong)(zhong)特(te)性、無(wu)病蟲(chong)為(wei)害的果實采(cai)種(zhong)(zhong)(zhong)。
有機白瓜以(yi)側(ce)(ce)蔓(man)(man)(man)、孫(sun)(sun)(sun)蔓(man)(man)(man)結瓜為(wei)主(zhu)(zhu)。根(gen)據雌(ci)雄(xiong)花著(zhu)生習性,主(zhu)(zhu)蔓(man)(man)(man)、側(ce)(ce)蔓(man)(man)(man)和孫(sun)(sun)(sun)蔓(man)(man)(man)應及時(shi)打(da)頂(ding)(ding)。打(da)頂(ding)(ding)原(yuan)則一般(ban)采(cai)用“五五三”制,即(ji)主(zhu)(zhu)蔓(man)(man)(man)、側(ce)(ce)蔓(man)(man)(man)、孫(sun)(sun)(sun)蔓(man)(man)(man)打(da)頂(ding)(ding)均(jun)在5片真葉時(shi)進行(xing),側(ce)(ce)蔓(man)(man)(man)和孫(sun)(sun)(sun)蔓(man)(man)(man)的蔓(man)(man)(man)條分別保(bao)留(liu)5條、3條;具(ju)體為(wei):主(zhu)(zhu)蔓(man)(man)(man)4—5片真葉時(shi)打(da)頂(ding)(ding),其后長(chang)(chang)出側(ce)(ce)蔓(man)(man)(man)4—5條,及時(shi)理蔓(man)(man)(man)使(shi)之(zhi)均(jun)勻分布(bu)在主(zhu)(zhu)蔓(man)(man)(man)兩側(ce)(ce)的畦面上(shang);每(mei)條側(ce)(ce)蔓(man)(man)(man)又(you)留(liu)4—5葉打(da)頂(ding)(ding),以(yi)促孫(sun)(sun)(sun)蔓(man)(man)(man)生長(chang)(chang)。一般(ban)每(mei)條側(ce)(ce)蔓(man)(man)(man)留(liu)2—3條孫(sun)(sun)(sun)蔓(man)(man)(man)為(wei)宜;孫(sun)(sun)(sun)蔓(man)(man)(man)再留(liu)4—5葉打(da)頂(ding)(ding),其上(shang)不(bu)再保(bao)留(liu)支蔓(man)(man)(man)。
及時打頂、理蔓是保證坐(zuo)果,提高種(zhong)子產量的(de)重(zhong)要保證。留蔓過多(duo),植(zhi)株(zhu)枝葉過繁,造成跑秧,而抑制生(sheng)殖生(sheng)長,不(bu)利于坐(zuo)果,產種(zhong)量低。
在施(shi)肥(fei)(fei)上有機(ji)白瓜(gua)采種田(tian)應(ying)(ying)根據其對養分的需要,掌(zhang)握多施(shi)有機(ji)肥(fei)(fei)的原則。在作(zuo)畦(qi)前,667m2施(shi)農家肥(fei)(fei)如豬糞(fen)1500—2000kg和復合肥(fei)(fei)20kg,追肥(fei)(fei)以無機(ji)肥(fei)(fei)為主,其中667m2氮肥(fei)(fei)10—15kg,采種田(tian)需肥(fei)(fei)量(liang)大,但坐(zuo)果(guo)前應(ying)(ying)適當控制肥(fei)(fei)水,防止(zhi)因植株生長(chang)(chang)過(guo)旺(wang)導(dao)致(zhi)化瓜(gua)。坐(zuo)瓜(gua)后,開始追肥(fei)(fei)澆水,保持植株長(chang)(chang)勢(shi),促進(jin)果(guo)實膨大。果(guo)實定型后,應(ying)(ying)適當控制水分,促進(jin)種子發育飽滿。
危害(hai)(hai)白瓜(gua)種瓜(gua)的(de)病(bing)(bing)蟲害(hai)(hai)主要有(you):綿腐病(bing)(bing)、炭疽(ju)(ju)病(bing)(bing)和潛葉蠅等。尤其是春(chun)植(zhi)(zhi)白瓜(gua),因華南地區(qu)春(chun)末(mo)至(zhi)夏初雨水多,高溫(wen)高濕(shi),植(zhi)(zhi)株匍(pu)匐生長,側蔓、果實(shi)(shi)常與地面(mian)接觸,容易(yi)發生病(bing)(bing)蟲害(hai)(hai)。炭疽(ju)(ju)病(bing)(bing)發生時,果實(shi)(shi)感病(bing)(bing)初為(wei)淡綠色(se)水漬小斑點,后(hou)擴(kuo)大為(wei)中間凹陷(xian)近圓形的(de)褐色(se)病(bing)(bing)斑,表面(mian)有(you)橙(cheng)色(se)粘稠物溢出(chu),致果實(shi)(shi)腐爛,注意(yi)科學防治。
采(cai)(cai)種(zhong)有(you)機白瓜(gua)(gua)于(yu)花后25—35天為(wei)收獲適(shi)期。此時(shi)(shi)果肉(rou)柔軟,果梗易(yi)脫落,皮色(se)變黃。華南地區(qu)5—6月份(fen)多高溫陰(yin)雨天氣,7—9月份(fen)為(wei)臺(tai)風季(ji)節(jie),因此,春植白瓜(gua)(gua)在6月份(fen)采(cai)(cai)種(zhong)期間,要(yao)保產保質,適(shi)時(shi)(shi)收獲種(zhong)瓜(gua)(gua),預(yu)防(fang)爛瓜(gua)(gua)是關鍵(jian);夏(xia)、秋植白瓜(gua)(gua)采(cai)(cai)種(zhong)時(shi)(shi),正值臺(tai)風季(ji)節(jie),由于(yu)白瓜(gua)(gua)耐(nai)澇性(xing)較差,要(yao)特(te)別注(zhu)意防(fang)澇、排澇,以免授(shou)粉(fen)植株被水(shui)淹,病蟲(chong)害發生嚴重。苦水(shui)淹超過24h(小時(shi)(shi)),則果實全部腐爛。
采收(shou)(shou)種(zhong)(zhong)瓜(gua)可(ke)根據種(zhong)(zhong)瓜(gua)成熟度分(fen)3—4次進行。種(zhong)(zhong)瓜(gua)采收(shou)(shou)后(hou),置(zhi)陰涼通(tong)風干燥處后(hou)熟3—7天,掏出種(zhong)(zhong)子(zi)(zi)和(he)瓜(gua)瓤,放置(zhi)在(zai)木、瓦質盆缸中發酵12—24h后(hou),用手(shou)揉搓(cuo),使種(zhong)(zhong)子(zi)(zi)和(he)瓜(gua)瓤分(fen)離,后(hou)用清(qing)水洗凈置(zhi)于通(tong)風干燥處晾干2—3天,再在(zai)陽光下曬干,最后(hou)置(zhi)于低溫(wen)干燥處,可(ke)保(bao)存(cun)3—5年。一般每(mei)株(zhu)采種(zhong)(zhong)瓜(gua)2—4個(ge),667m2可(ke)采收(shou)(shou)種(zhong)(zhong)子(zi)(zi)20—30kg。種(zhong)(zhong)子(zi)(zi)卵(luan)形,淺黃白色,千粒重16—17g。