【作者】 罗佳；

【导师】 邹志荣；

【作者基本信息】 西北农林科技大学 ， 园艺， 2008， 硕士

【摘要】 本试验以番茄为研究材料,通过分析四种棚龄土壤和番茄果实内硝酸盐含量的变化,探讨了随着棚龄变长,土壤和番茄果实内硝酸盐累积的规律。又在相对应不同棚龄（10年,7年,5年,3年）大棚内分别对番茄施用了不同浓度（高,中,低）的ALA、DCD,以引起番茄果实NO₃^-,NO₂^-含量和有关营养品质（糖度,番茄红素,总酸,VC和β胡萝卜素）含量的变化。通过频数分布法、回归分析法、相关分析法和差异的显著性检验,揭示了施用ALA、DCD后所产生的番茄安全品质（NO₃^-,NO₂^-含量）和营养品质的调控效应。结果表明:（1）随着棚龄的变长,番茄果实内的硝酸盐含量有明显的上升趋势。这和土壤内硝酸盐含量有较明显上升密切相关。土壤和番茄果实内的硝酸盐含量上升速度相比较,番茄果实的升速明显较快,似乎存在着由土壤污染引起的激发、放大效应。（2）长龄棚和短龄棚比较,硝酸盐在土壤各个层次的含量都较短龄棚同层次的含量为高;在垂直方向上,长龄棚和短龄棚内土壤硝酸盐含量均随深度增加而减少,但长龄棚的递减梯度较短龄棚为大。从而造成在土壤深层长龄棚和短龄棚的硝酸盐含量趋于接近的态势。（3）施用ALA和DCD后,取得抑制番茄果实内NO₃^-,NO₂^-累积的较好效果,尤其对于硝酸盐和亚硝酸盐含量较高的长龄棚,抑制效果更好。在ALA和DCD的浓度试验范围内,随着浓度增加,对NO₃^-,NO₂^-累积的抑制效应明显上升。从对NO₃^-,NO₂^-累积抑制的比较看,对后者的抑制效果更佳。（4）施用ALA和DCD后,不但取得抑制番茄果实内NO₃^-,NO₂^-累积的较好效果,且对番茄果实的营养品质有所改善,在品质中以对糖度,番茄红素和总酸含量的改善更为明显。ALA和DCD的作用相比较,ALA的改善营养品质的效应明显超过DCD的效应。若对番茄果实NO₃^-,NO₂^-累积的抑制效应和改善营养品质的效应进行综合评价,则ALA的作用在总体上超过了DCD的。（5）施用ALA和DCD后,番茄果实内NO₃^-,NO₂^-含量的变化和其营养品质的变化并不是彼此独立的现象,而是具有一定关联,其中NO₃^-,NO₂^-累积机的抑制水平和糖度增加幅度呈明显负相关;其次,和VC含量增加亦有一定负相关关系。这启示人们在采取施用ALA或DCD的措施时,既要考虑对提高番茄果实安全品质的效用,又要考虑对改善番茄营养品质的效用,应全面衡量、综合评价,争取获得双赢的最好结果。更多还原

【Abstract】 Tomato was the material in the experiment. The nitrate cumulation law of tomato and soil was investigated with age of the facilities by analyzing the nitrate content change of tomato and soil in four age of greenhouse. Different concentration （high, middle, low） of ALA and DCD application on tomato in different age of greenhouse （10 years,7 years, 5 years, 3years） induced the changes of NO₃^-, NO₂^- and nutritive quality content （sugar content, lycopene, total acid, VC,β-Carotene ）. By using frequency analysis method, regression analysis method, correlative analysis method, difference significance test, revealed the security quality （the NO₃^-, NO₂^- content） and nutritive quality regulating effect of ALA and DCD application on tomato. The result as follows:（1） The nitrate content of tomato keep rising with age of greenhouse. It is related to the nitrate content rising of soil. Comparing the increasing speed of tomato fruit and soil, tomato fruit increased rapider than soil, the stimulated amplifying effect induced by the soil pollution maybe exist.（2） The nitrate content in different soil levels of old-aged greenhouses is higher than the young-aged ones. The nitrate content of old-aged and young-aged greenhouses decreased with the increase of depth in perpendicular direction, but the old-aged greenhouses’decreasing gradient were larger than the young-aged ones, it induced that the old-aged greenhouses’nitrate content was closed to the young-aged ones in deep layers of soil.（3） The NO₃^-, NO₂^- cumulation of tomato fruit was inhibited by the ALA and DCD application. The inhibition effect is better to the old-aged greenhouse with high nitrate and nitrite content. The NO₃^-, NO₂^- cumulation inhibition effect was increased obviously with the increasing concentration in the concentration range. The inhibition effect of NO₂^-was better than NO₃^-.（4） By applying ALA and DCD, not only the NO₃^-, NO₂^- cumulation was inhibited, but also improved the nutritive quality of tomato fruit, it’s more distinct to the sugar content, lycopene and total acid in the 5 qualities. ALA had more distinctness effect than DCD. Comprehensive evaluate the effect to tomato fruit on the NO₃^-, NO₂^- cumulation inhibition and nutritive quality improving effect, ALA was better than DCD.（5） By applying ALA and DCD, the tomato fruit’s change of the NO₃^-, NO₂^- content and the nutritive quality is correlated. The NO₃^-, NO₂^- cumulation inhibition quality and sugar content increase range presented obviously negative correlation, in the next place, it is also negative correlation to the increasing of the VC content. It implied that when people applying ALA or DCD, they would not only think over the effect to improve the tomato security quality, but also concentrate on the effect to improve the tomato nutritive quality, take into account comprehensively, strive after the win-win result.更多还原