Dominance of bush growth habit in spaghetti squash (Cucurbita pepo)

Summary Bush and vine habit accessions and their reciprocal F₁s of spaghetti squash (Cucurbita pepo) were compared for various vegetative and reproductive characteristics. Bush habit was dominant to vine. Vine plants produced more leaves, longer internodes, and more male flowers than did bush and F₁ plants. Pistillate flowers developed at lower nodes in bush and F₁ plants than in vine plants. Vine plants produced as much or more vegetative matter than did bush and F₁ plants, but bush and F₁ plants produced more fruits and greater yields than did vine plants.     

Phenotypic and marker‐assisted pyramiding of genes for resistance to zucchini yellow mosaic virus in oilseed pumpkin (Cucurbita pepo)

We report on the identification of phenotypic and molecular markers for genes introgressed into oilseed pumpkin Cucurbita pepo from C. moschata germplasm originating in Nigeria, Portugal and Puerto Rico, which provide resistance against zucchini yellow mosaic virus (ZYMV) and on pyramiding these genes for improved and long‐lasting field protection of oilseed pumpkins. One SCAR and two SSR markers have been found for three dominant resistance genes, Zym‐0, Zym‐1 and Zym‐2. Characteristic reactions to ZYMV inoculation of plants carrying the recessive genes for resistance zym‐4* and zym‐6 have been defined. Described are procedures and results of pyramiding various combinations of these genes in oilseed pumpkin using the three markers and the specific phenotypic reactions to infection of some of these genes. The putative combination of all six resistance genes in one genotype resulted in a resistance that appeared to be at least as strong as or even stronger than that of the resistance source germplasm in C. moschata.     

部分南瓜品种资源数量分类初步研究

选取25个主要分类性状,对22个南瓜品种进行了数量分类研究。通过Q型聚类分析,综合考虑多个性状,反映出各品种之间的亲缘及演化关系。结果表明:Q型聚类分析得出的树系图,可以明显地将22种南瓜材料归为4类,即美洲南瓜、中国南瓜、印度南瓜和黑籽南瓜,与传统分类学的结果相符;R型聚类分析反映了各性状的信息,揭示了南瓜品种分类的关键,为今后进行性状观察、记载及取舍等提供了定量依据;同时,还探讨了南瓜品种间的亲缘关系。     

南瓜籽粕酶法制备血管紧张素转化酶抑制肽工艺优化

用中性蛋白酶水解南瓜籽粕,制备血管紧张素转换酶（angiotensin-converting enzyme,ACE）抑制肽,是南瓜籽粕蛋白深度开发的途径之一。为了探寻南瓜籽粕酶法制备ACE抑制肽的最佳工艺,该文以ACE抑制率为响应值,用响应面分析法研究酶浓度、底物质量浓度和水解时间等因素对酶解产物的ACE抑制活性的影响,优化制备工艺。结果表明,各因素对制备ACE抑制肽的活性具有极显著影响（P<0.001）。获得中性蛋白酶水解南瓜籽粕制备ACE抑制肽的最佳工艺条件为：酶体积分数为4.8%、底物质量浓度为4.0g/100 mL、水解时间为320 min。在此条件下,南瓜籽粕蛋白酶解产物对ACE的理论抑制率最高可达80.0％,验证值为80.56％±0.23%,预测模型可靠性高,可应用于南瓜籽粕ACE抑制肽的酶法制备。通过优化,提高了南瓜籽粕ACE抑制肽的活性。     

硝酸钙胁迫对南瓜幼苗生长和膜脂过氧化的影响

以温室专用南瓜品种蜜冠为材料,采用砂培法,研究了不同浓度Ca(NO3)2胁迫对南瓜幼苗生长和膜脂过氧化的影响。结果表明,随着Ca(NO3)2浓度提高(0~100 mmol/L),南瓜幼苗株高、茎粗、根长、叶片数及植株干质量和鲜质量均显著降低;0~75 mmol/L Ca( NO3)2条件下,叶绿素a、叶绿素b、类胡萝卜素和丙二醛含量及质膜相对透性显著增加,抗坏血酸含量则显著降低。表明Ca( NO3)2胁迫造成了南瓜幼苗膜脂过氧化伤害,而幼苗的抗氧化能力降低,使南瓜幼苗生长受到严重抑制。     

早熟优质南瓜新品种兴蔬红蜜一号的选育

兴蔬红蜜一号南瓜是由两个自交系N92和N97配制而成的一代杂种,早熟,抗白粉病,生长势强,第一雌花节位17节左右,主侧蔓均可结瓜,果实长葫芦形,成熟果桔红色带条形斑纹,果面有棱沟,商品瓜长41 cm左右。果实可溶性固形物含量8.8%左右,口感粉甜、肉质细腻,开花至采收40 d左右。单果重3.5~5.0 kg,一般产量4 000 kg/667m2左右。适于华中、华南早熟露地爬地栽培。     

南瓜侧蔓扦插繁殖初探

为提高南瓜繁殖率,实现优良品种的快速推广,对南瓜侧蔓进行了10次扦插试验,各次扦插分别在室外自然条件、室内无阳光直射、室外遮阳网、室内萘乙酸生根液、室外漂浮苗床等处理条件下完成。结果表明,扦插苗成活率在20%~92%不等,其中以第3次(6月21日)室内环境下、无阳光直射、温度为25~30℃、空气湿度70%左右处理的成活率最高。根据成活率趋势认为,随着秧龄的延长,成活率呈下降趋势;采用适度遮阳手段,降低温度,可明显提高扦插成活率;而萘乙酸对成活率的影响不大。     

超声波辅助浸提南瓜多糖的工艺研究

研究了超声波频率、浸提时间、固液比和提取液pH值等因素对多糖提取量的影响,并通过正交试验得到了超声波提取南瓜多糖的最佳工艺参数为:超声波频率为13kHz,提取时间15min,固液比为1g∶30mL,提取液pH值为10,在此条件下南瓜多糖的提取量为27.63mg/g。     

南瓜红薯营养粉条生产工艺

红薯粉条具有独特的风味,在传统粉条中添加南瓜全乳可改善其品质,提高其营养价值。介绍了南瓜红薯营养粉条的生产工艺。     

早熟南瓜新品种红阳南瓜的选育

红阳南瓜是以自交系Y-3-7-9-2-11为母本,以Y-5-1-9为父本配制而成的印度南瓜一代杂种。植株蔓生,生长势较强,早熟,第1雌花节位为6～8节,从开花到果实成熟40 d（天）左右,全生育期102 d（天）;果实扁圆形,果皮橙红色,果面光滑亮泽,外形美观,果肉橙红色,肉厚3.0 cm左右,肉质致密,口感甜糯,粉质度高,具板栗香味,品质佳。田间调查表明对白粉病、病毒病的抗性强于对照红蜜南瓜。单果质量1.5 kg左右,一般每667 m2产量3 000～4 000 kg,适宜早春露地及春秋保护地栽培。