白瓜又叫稍瓜、生瓜、越瓜、酥瓜、田瓜等,屬葫蘆科。白(bai)瓜(gua)外皮(pi)光(guang)滑,有縱長線條,汁多、質脆。可(ke)以生(sheng)吃(chi),亦(yi)可(ke)做菜、湯等(deng)。
主要分布于亞(ya)洲(zhou)熱帶、亞(ya)熱帶地區,澳大(da)利(li)亞(ya)東(dong)部,馬達加(jia)斯加(jia);我國各地栽培。
一年生蔓(man)生草本;莖(jing)密被黃褐(he)色(se)毛(mao)。卷須(xu)常(chang)分2-3叉;葉柄粗(cu)壯;葉片腎狀近圓(yuan)形,寬10-30厘米(mi),基部灣缺深,5-7淺(qian)裂或有(you)時中裂,邊緣有(you)小(xiao)鋸(ju)齒,兩面(mian)生有(you)硬毛(mao)。
雌雄同株;花(hua)(hua)單(dan)生(sheng)(sheng),花(hua)(hua)梗被(bei)硬(ying)毛(mao);花(hua)(hua)萼裂片(pian)有鋸(ju)齒,反折;花(hua)(hua)冠黃色(se),輻狀(zhuang),裂片(pian)寬倒卵(luan)形(xing),長3-6厘(li)米;雄蕊3,分(fen)生(sheng)(sheng),藥室多回折曲;子房卵(luan)形(xing)或圓(yuan)筒(tong)形(xing),密生(sheng)(sheng)黃褐(he)色(se)硬(ying)毛(mao),柱(zhu)頭(tou)3, 2裂。果實長圓(yuan)柱(zhu)狀(zhuang)或近球狀(zhuang),大型(xing),有毛(mao)和(he)白(bai)粉;種(zhong)子卵(luan)形(xing),白(bai)色(se)或淡黃色(se),壓扁狀(zhuang)。
白(bai)瓜屬喜溫作物,耐(nai)寒性差(cha),一(yi)般在當地斷(duan)霜后,土溫15℃和氣溫20℃以上的季節栽培。
白(bai)瓜(gua)為大眾經常食用(yong)的(de)蔬(shu)菜,有(you)非常高的(de)藥用(yong)價值,白(bai)瓜(gua)的(de)營養成分:每100克(ke)(ke)(ke)(ke)(ke)白(bai)瓜(gua)中含(han)有(you)蛋白(bai)質0.9克(ke)(ke)(ke)(ke)(ke),糖2.9克(ke)(ke)(ke)(ke)(ke),熱量62.7千焦,鈣24毫(hao)(hao)(hao)克(ke)(ke)(ke)(ke)(ke),磷(lin)1l毫(hao)(hao)(hao)克(ke)(ke)(ke)(ke)(ke),鐵0.2毫(hao)(hao)(hao)克(ke)(ke)(ke)(ke)(ke),胡蘿卜(bu)素(su)0.02毫(hao)(hao)(hao)克(ke)(ke)(ke)(ke)(ke),維生(sheng)素(su)B1 0.02毫(hao)(hao)(hao)克(ke)(ke)(ke)(ke)(ke),維生(sheng)素(su)B2 0.03毫(hao)(hao)(hao)克(ke)(ke)(ke)(ke)(ke),尼克(ke)(ke)(ke)(ke)(ke)酸0.2毫(hao)(hao)(hao)克(ke)(ke)(ke)(ke)(ke),維生(sheng)素(su)白(bai)瓜(gua)的(de)功效:白(bai)瓜(gua)性(xing)味甘、寒,有(you)利小便、解(jie)熱毒的(de)作用(yong),可治煩(fan)熱口渴,小便不利等(deng)癥(zheng)。
白瓜富(fu)含(han)蛋白質(zhi)(zhi)、礦(kuang)物質(zhi)(zhi)和維生(sheng)素等物質(zhi)(zhi),不含(han)脂肪(fang),還含(han)有(you)瓜氨酸、腺嘌(piao)呤、天門冬氨酸等物質(zhi)(zhi),且含(han)鈉鹽很(hen)低。
白瓜(gua)屬葫蘆科甜瓜(gua)屬一(yi)年(nian)生(sheng)蔓生(sheng)植(zhi)物,近年(nian)來,白瓜(gua)種植(zhi)面(mian)積(ji)不斷(duan)擴大,種子需求量不斷(duan)增加,但由于受華南(nan)地區特殊的氣候因素制(zhi)約,白瓜(gua)采種時常出現種瓜(gua)腐爛現象,嚴重影響(xiang)留種效益。
有機白瓜(gua)屬喜溫作物,耐(nai)寒性差(cha),一般在當地斷(duan)霜后(hou),土溫15℃和氣溫20℃以上的季節(jie)栽培(pei)。在廣東,適(shi)播(bo)(bo)期為4—8月,春植白瓜(gua)一般在清明后(hou)直播(bo)(bo),播(bo)(bo)種太早,易受凍害,出苗緩慢且不整齊,影響植株中后(hou)期生長(chang)發育和種子形(xing)成。
由(you)于華(hua)南地區降雨量(liang)大,多采(cai)用高畦、深(shen)排水溝、覆地膜(或(huo)稻草、蕨類植(zhi)物芒箕等)栽培。為提高種子產(chan)量(liang),采(cai)種田應合理(li)密植(zhi)。一般采(cai)用單(dan)行(xing)植(zhi)或(huo)雙行(xing)植(zhi),單(dan)行(xing)株距18—20cm,行(xing)距130—150cm;雙行(xing)株距40—60cm,行(xing)距150—200cm,每穴2—4粒,667m2栽3000—3500株。
白瓜是雌雄異花(hua)(hua)同株的蟲媒花(hua)(hua)植物,品(pin)種(zhong)(zhong)間容易發生(sheng)自然(ran)雜交,要求(qiu)在采種(zhong)(zhong)田周圍1500cm以內無(wu)甜(tian)瓜屬的其他品(pin)種(zhong)(zhong)同期開(kai)花(hua)(hua)。在此(ci)隔離條件(jian)下,可(ke)完全由昆(kun)蟲自由授(shou)粉留(liu)種(zhong)(zhong)。為了提高產量可(ke)采用人工(gong)輔助授(shou)粉方式留(liu)種(zhong)(zhong)。
人工輔(fu)助授粉時,在選定的雌(ci)(ci)花(hua)(hua)(hua)(hua)(hua)(hua)開放前l天下午,用(yong)3cm長(chang)的鋁(lv)線(xian)碼(ma)同(tong)時分別夾(jia)住同(tong)一(yi)種株上的雌(ci)(ci)花(hua)(hua)(hua)(hua)(hua)(hua)和雄花(hua)(hua)(hua)(hua)(hua)(hua)花(hua)(hua)(hua)(hua)(hua)(hua)冠(guan),松緊適度;然(ran)后于(yu)開花(hua)(hua)(hua)(hua)(hua)(hua)當日(ri)上午8—11時,采(cai)集夾(jia)過的雄花(hua)(hua)(hua)(hua)(hua)(hua),去掉花(hua)(hua)(hua)(hua)(hua)(hua)瓣(ban),用(yong)雄花(hua)(hua)(hua)(hua)(hua)(hua)花(hua)(hua)(hua)(hua)(hua)(hua)藥輕抹(mo)雌(ci)(ci)花(hua)(hua)(hua)(hua)(hua)(hua)柱頭后,用(yong)原鋁(lv)線(xian)碼(ma)夾(jia)住雌(ci)(ci)花(hua)(hua)(hua)(hua)(hua)(hua)花(hua)(hua)(hua)(hua)(hua)(hua)冠(guan),并掛牌標(biao)記,一(yi)般(ban)一(yi)朵雄花(hua)(hua)(hua)(hua)(hua)(hua)可授1—2朵雌(ci)(ci)花(hua)(hua)(hua)(hua)(hua)(hua)。
為保(bao)證種(zhong)(zhong)子(zi)純度,必(bi)須進行種(zhong)(zhong)株(zhu)及種(zhong)(zhong)瓜(gua)的(de)選擇。首先,在定苗(miao)前,選擇生(sheng)長(chang)(chang)一致、無(wu)(wu)病蟲危(wei)害(hai)、無(wu)(wu)畸(ji)形(xing)表(biao)現的(de)幼苗(miao)定苗(miao);其次,在開(kai)花(hua)(hua)坐(zuo)果時,選生(sheng)長(chang)(chang)勢中等,雌花(hua)(hua)節位(wei)適中,無(wu)(wu)畸(ji)形(xing)表(biao)現和無(wu)(wu)病蟲危(wei)害(hai)的(de)植株(zhu)作(zuo)種(zhong)(zhong)株(zhu),授粉坐(zuo)果后,分期(qi)選生(sheng)長(chang)(chang)正(zheng)常的(de)果實(shi)作(zuo)種(zhong)(zhong)瓜(gua),并掛牌標記;最后,在種(zhong)(zhong)瓜(gua)采(cai)收時選瓜(gua)形(xing)正(zheng)常、符(fu)合品種(zhong)(zhong)特(te)性(xing)、無(wu)(wu)病蟲為害(hai)的(de)果實(shi)采(cai)種(zhong)(zhong)。
有機白瓜(gua)以(yi)側(ce)蔓(man)(man)(man)(man)(man)、孫(sun)(sun)蔓(man)(man)(man)(man)(man)結(jie)瓜(gua)為(wei)主(zhu)。根(gen)據雌雄花著生習性,主(zhu)蔓(man)(man)(man)(man)(man)、側(ce)蔓(man)(man)(man)(man)(man)和孫(sun)(sun)蔓(man)(man)(man)(man)(man)應及(ji)時(shi)打頂(ding)。打頂(ding)原則一(yi)般采(cai)用(yong)“五五三”制,即(ji)主(zhu)蔓(man)(man)(man)(man)(man)、側(ce)蔓(man)(man)(man)(man)(man)、孫(sun)(sun)蔓(man)(man)(man)(man)(man)打頂(ding)均在5片真葉時(shi)進(jin)行,側(ce)蔓(man)(man)(man)(man)(man)和孫(sun)(sun)蔓(man)(man)(man)(man)(man)的蔓(man)(man)(man)(man)(man)條分(fen)別保留(liu)5條、3條;具體為(wei):主(zhu)蔓(man)(man)(man)(man)(man)4—5片真葉時(shi)打頂(ding),其后(hou)長出側(ce)蔓(man)(man)(man)(man)(man)4—5條,及(ji)時(shi)理蔓(man)(man)(man)(man)(man)使之均勻分(fen)布在主(zhu)蔓(man)(man)(man)(man)(man)兩側(ce)的畦面上;每條側(ce)蔓(man)(man)(man)(man)(man)又留(liu)4—5葉打頂(ding),以(yi)促(cu)孫(sun)(sun)蔓(man)(man)(man)(man)(man)生長。一(yi)般每條側(ce)蔓(man)(man)(man)(man)(man)留(liu)2—3條孫(sun)(sun)蔓(man)(man)(man)(man)(man)為(wei)宜(yi);孫(sun)(sun)蔓(man)(man)(man)(man)(man)再(zai)留(liu)4—5葉打頂(ding),其上不(bu)再(zai)保留(liu)支蔓(man)(man)(man)(man)(man)。
及時打(da)頂、理蔓是保(bao)證坐(zuo)(zuo)果,提高種子產量的重要保(bao)證。留(liu)蔓過(guo)多(duo),植(zhi)株枝(zhi)葉過(guo)繁,造成跑秧,而(er)抑制生殖生長,不利于坐(zuo)(zuo)果,產種量低。
在(zai)施(shi)肥上有機(ji)白瓜采種(zhong)田應(ying)根(gen)據其對養分的需要,掌(zhang)握(wo)多施(shi)有機(ji)肥的原(yuan)則(ze)。在(zai)作(zuo)畦前,667m2施(shi)農家肥如豬糞1500—2000kg和復合肥20kg,追(zhui)肥以無機(ji)肥為主(zhu),其中(zhong)667m2氮(dan)肥10—15kg,采種(zhong)田需肥量大,但坐(zuo)果(guo)前應(ying)適(shi)當控制(zhi)肥水(shui),防止因(yin)植株(zhu)生長過旺導致化瓜。坐(zuo)瓜后,開始追(zhui)肥澆水(shui),保持植株(zhu)長勢,促進(jin)果(guo)實膨(peng)大。果(guo)實定型后,應(ying)適(shi)當控制(zhi)水(shui)分,促進(jin)種(zhong)子發育飽滿(man)。
危(wei)害(hai)(hai)白(bai)瓜種瓜的病(bing)蟲害(hai)(hai)主(zhu)要有:綿(mian)腐(fu)病(bing)、炭(tan)疽病(bing)和潛葉蠅等。尤(you)其是春植(zhi)白(bai)瓜,因華南(nan)地(di)區(qu)春末至夏初雨水(shui)多,高(gao)溫高(gao)濕,植(zhi)株匍匐(fu)生(sheng)長,側蔓、果(guo)實(shi)常與地(di)面接觸,容易(yi)發(fa)生(sheng)病(bing)蟲害(hai)(hai)。炭(tan)疽病(bing)發(fa)生(sheng)時,果(guo)實(shi)感病(bing)初為(wei)淡綠色水(shui)漬小斑點,后擴(kuo)大(da)為(wei)中(zhong)間凹陷(xian)近(jin)圓形的褐色病(bing)斑,表面有橙色粘(zhan)稠物溢出,致(zhi)果(guo)實(shi)腐(fu)爛,注意科(ke)學防治。
采種(zhong)有機白瓜(gua)(gua)于花(hua)后25—35天(tian)為收獲適期。此(ci)時果(guo)肉柔軟,果(guo)梗易脫落(luo),皮色變黃。華南地區5—6月(yue)份多(duo)高(gao)溫陰雨天(tian)氣,7—9月(yue)份為臺風(feng)季(ji)節,因(yin)此(ci),春植(zhi)白瓜(gua)(gua)在6月(yue)份采種(zhong)期間,要(yao)保產保質,適時收獲種(zhong)瓜(gua)(gua),預(yu)防爛瓜(gua)(gua)是關鍵;夏、秋植(zhi)白瓜(gua)(gua)采種(zhong)時,正值(zhi)臺風(feng)季(ji)節,由于白瓜(gua)(gua)耐澇性較差,要(yao)特別注意防澇、排(pai)澇,以免(mian)授粉植(zhi)株被水(shui)淹(yan),病(bing)蟲害發生嚴重。苦水(shui)淹(yan)超(chao)過24h(小時),則果(guo)實全(quan)部腐爛。
采收(shou)(shou)種(zhong)(zhong)(zhong)瓜(gua)(gua)可(ke)(ke)根(gen)據(ju)種(zhong)(zhong)(zhong)瓜(gua)(gua)成熟(shu)度分(fen)3—4次進行。種(zhong)(zhong)(zhong)瓜(gua)(gua)采收(shou)(shou)后,置(zhi)陰(yin)涼通(tong)風(feng)干(gan)(gan)燥處后熟(shu)3—7天(tian),掏出種(zhong)(zhong)(zhong)子(zi)和(he)瓜(gua)(gua)瓤,放(fang)置(zhi)在木、瓦質盆缸中發酵12—24h后,用手揉搓,使(shi)種(zhong)(zhong)(zhong)子(zi)和(he)瓜(gua)(gua)瓤分(fen)離,后用清水洗凈置(zhi)于通(tong)風(feng)干(gan)(gan)燥處晾(liang)干(gan)(gan)2—3天(tian),再在陽(yang)光下曬(shai)干(gan)(gan),最(zui)后置(zhi)于低溫(wen)干(gan)(gan)燥處,可(ke)(ke)保存3—5年。一般每株采種(zhong)(zhong)(zhong)瓜(gua)(gua)2—4個(ge),667m2可(ke)(ke)采收(shou)(shou)種(zhong)(zhong)(zhong)子(zi)20—30kg。種(zhong)(zhong)(zhong)子(zi)卵形,淺黃白色(se),千粒重(zhong)16—17g。