镉离子诱导对洋葱根尖及表皮细胞凋亡的影响研究

以洋葱根尖细胞和鳞茎内表皮细胞为试材,用不同浓度氯化镉溶液为诱导剂,研究Cd2+对洋葱根尖凋亡的影响。结果表明:Cd2+能诱发根尖细胞凋亡和染色体畸变,且凋亡现象随着Cd2+处理浓度的增加和处理时间的延长而严重,有微核出现和细胞核逐渐解体等现象;洋葱表皮细胞随Cd2+浓度增高及处理时间的延长,表皮细胞逐渐发生质壁分离,而且越来越严重,并且细胞核发生偏离,逐渐靠近细胞壁等现象。     

Quality preservation of salted,vacuum packaged and refrigerated mahi sefid (Rutilus frisii kutum) fillets using an onion (Allium cepa) extract

The combined effect of light salting, vacuum packaging and onion extract on the shelf life of mahi sefid (Rutilus frisii kutum) fillets under refrigeration was assessed using chemical, microbiological and sensory methods. The shelf life of control, air‐packaged, salted (APS), vacuum‐packaged, salted (VPS) and vacuum‐packaged, salted with onion extract (VPSOE) samples was determined to be up to 6, 9, 15 and 18 days respectively. The values of total volatile basic nitrogen, free fatty acid and thiobarbituric acid increased progressively during the storage period for all the treatments. However, the preservative methods applied led to an extended shelf life of fillets based on chemical indices and sensory attributes in the following order: VPSOE>VPS>APS>control group. The assay of the total viable count (TVC) revealed that 2% and 4%VPSOE produced a decrease in TVC throughout the storage period. According to the results obtained, the best method to preserve the mahi sefid fillet was by 4%VPSOE treatment.     

外源脱落酸对洋葱鳞茎休眠的影响

研究了不同浓度外源脱落酸(ABA)对洋葱鳞茎休眠的影响.结果表明:10 μmol·L-1的ABA处理效果最好,其贮存100 d后的鳞茎发芽率只有2.9%,比对照低63.8%.进一步对ABA处理后洋葱不同部位的可溶性蛋白、可溶性糖含量和过氧化物酶(POD)、超氧化物歧化酶(SOD)活性变化进行了研究.结果表明:从处理后第1天至第4天,新叶除了POD活性外其他指标处理后均高于对照;鳞茎内层可溶性蛋白和可溶性糖含量处理后均低于对照;SOD和POD在处理后前期低于对照,处理1 d后逐步高于对照.处理4 d后各部位除了POD活性外,其他指标和对照基本一致.     

不同营养液配方对红葱生长及品质影响

研究4个营养液配方对红葱生长及营养品质的影响,结果发现:在水培条件下,从栽种开始前40d红葱生长主要是茎叶生长,40d~55d分蘖数急剧增加,茎叶生长量也继续增加;栽种前40d内配方T4较好,红葱产量较高,可溶性糖、可溶性蛋白、Vc含量高,硝酸盐含量最低。生产上可采用配方T4,并及时采收产品。     

五层网带式洋葱穿流干燥系统的设计

针对我国果蔬网带式干燥设备存在的干燥效率低、能耗大、自动化程度低、干燥品质差等问题,结合洋葱的干燥特性,设计了一套适用于洋葱干燥的五层网带式穿流干燥系统.该系统由机架、金属网带、供风系统、换热系统、上料机构组成,可实现金属网带自动清洗、自动调速以及分段、分区控温控时的功能,该系统干燥效率与生产效率较高,含水率为8%的洋葱丁的生产率可达300kg/h.     

葱苗性状、移栽方式对大葱产量的多元回归分析

以章丘大葱"大梧桐"品种为试材,研究了秋季育苗和春季育苗、切葱叶和不切葱叶、葱苗大小分级处理对大葱株高、葱白长、葱白直径、单株重以及单位面积产量的影响。结果表明:在本试验条件下以秋不切葱叶1级苗处理的总体农艺性状表现最好。葱苗大小对大葱各农艺性状影响显著;切葱叶显著降低大葱叶片数,但对1级苗产量影响较小,对2级苗和3级苗的产量影响较大;秋季育苗的株高和葱白长显著高于春季育苗。葱白直径和株高显著影响大葱单株重和单位面积产量。     

大葱苗期除草剂初步筛选

为了探索大葱田安全高效的除草技术,推进大葱规模化简易生产,在室内条件下对大葱除草剂进行了筛选.结果表明,330 g/L二甲戊乐灵495(推荐剂量)～1 485 g/hm2在药后18 d和27d对禾本科杂草的防效较好,药效达到4级;30％辛酰溴苯腈375 g/hm2(推荐剂量)在药后18 d和27 d对阔叶杂草的防效较好,药效达到3级,且它们对大葱基本无药害,可在大葱田推荐使用.50％乙草胺、960 g/L精异丙甲草胺、480 g/L灭草松、50 g/L精喹禾灵、15％精吡氟禾草灵虽对部分杂草有较好防效,但会对葱苗产生轻度至中度药害,应限制使用.大葱对25％扑草净、90％莠去津、200 g/L氯氟吡氧乙酸、50％异丙隆较敏感,在大葱田严禁使用这4种除草剂.     

Recovery of Pantoea ananatis, causal agent of center rot of onion, from weeds and crops in Georgia, USA

Center rot of onion, caused by Pantoea ananatis, has been a problem of sweet onions in Georgia since 1997. A polymerase chain reaction (PCR) protocol was developed to screen for populations of P. ananatis on plant surfaces. Plant samples producing a positive PCR reaction were targeted for further processing to culture the bacterium. In a survey of the Vidalia onion-growing region of Georgia, we detected and cultured P. ananatis from 25 asymptomatic weed species, which included commonly occurring weeds such as crabgrass (Digitaria sanguinalis), Florida beggarweed (Desmodium tortuosum), Florida pusley (Richardia scabra), sicklepod (Cassia obtusifolia), Texas Millet (Panicum texanum), tall verbena (Verbena bonariensis) and yellow nutsedge (Cyperus esculentus). In addition, the bacterium was recovered from crop plants such as Bermuda grass (Cynodon dactylon), cowpea (Vigna unguiculata) and soybean (Glycine max). Based on the field survey and tests with strains held in storage in the Coastal Plain Experiment Station culture collection, we concluded that P. ananatis was in Georgia prior to 1997, and was distributed widely on weeds and crops throughout southern Georgia.     

氮肥减施与氨基酸液体肥增施对露地膜下滴灌洋葱生长、产量和品质的影响

【目的】分析减少不同氮肥施用量和增施不同氨基酸液体肥施用量对洋葱植株性状、产量和品质的影响。【方法】以白皮洋葱白雪为试材,设置4个施氮水平,25(CK)、20(N₁)、17.5(N₂)、15 kg/667m²(N₃);3个氨基酸液体肥施用量,22(M₁)、26(M₂)、28 kg/667m²(M₃),共10个处理。在洋葱鳞茎膨大中期测洋葱形态指标,在采收时测洋葱鳞茎形态指标和产量指标,采收后测洋葱鳞茎的品质指标。【结果】在减氮20%(N₁)、30%(N₂)这2组中,随着氨基酸液体肥使用量的增加,与CK相比,洋葱植株形态指标的株高、茎粗与叶长较CK平均分别增加了4.09%、3.91%、7.51%与4.76%、5.74%、6.90%;洋葱植株鳞茎的横茎与纵茎较CK平均分别增加了3.27%、4.86%与3.19%、4.71%;洋葱的产量较CK平均增加了10%、6.61%;品质指标上,硝酸盐含量较CK平均降低了30.11%、25.53%;可溶性固形物较CK平均增加了6.68%、8.86%;可溶性蛋白较CK平均增加了43.09%、75.61%;VC含量较CK平均增加了1.64、1.58(mg/100g)。减氮20%(N₁)与30%(N₂)施用氨基酸液体肥这2组之间相比,前者比后者产量和经济效益平均分别增加了3.15%、3.43%;品质指标上可溶性固形物、可溶性蛋白与可溶性糖含量后者较前者平均分别增加了2.10%、23.08%与20.40%。【结论】减氮量为20%(N₁)时,氨基酸液体肥施用量为M₁、M₂时,洋葱的产量最高,品质较好;减氮量为30%(N₂)时,氨基酸液体肥施用量为M₁、M₂时,洋葱的品质表现的最好,产量指标较好。     

机械深松技术对大葱产量影响研究

为了研究机械深松技术对大葱生长发育和产量的影响,在陕西乾县“漠西大葱”示范基地布置大田试验。通过连续两个年度试验表明：大葱栽培使用机械深松技术后,土壤深松深度可达40~45 cm,与非机械深松大葱相比,平均每株葱高、次生根数量、根系长度、葱根以上10 cm葱白直径、葱白长度和葱重都有不同程度的增加,平均增产16.0%和31.6%。该研究为大葱生产推广应用机械深松技术提供了理论依据。同时在机械深松时必须保证土壤墒情良好,若墒情较差,需及时进行喷灌或浇灌,和墒时机械深松、开沟移栽。避免因土壤墒情差,深松后造成土壤疏松,开沟质量差,沟槽不成型,增加大葱移栽的难度,影响移栽质量。