番茄秸秆堆肥提高番茄果实风味的适宜添加比例研究

【目的】我国蔬菜生产面积大,食用部分收获后的蔬菜废弃物剩余量大,需要妥善处理。本文以番茄秸秆废弃物为原料进行堆肥,研究了其与菜园土混合作为基质用于番茄生产后,对番茄果实挥发性物质含量的影响,为番茄秸秆堆肥的科学应用提供依据。【方法】选用陕西地区的主栽番茄品种‘金棚1号’为试验材料,以常规基质 (氮磷钾总养分含量 ≥ 2%,有机质 ≥ 30%) 栽培为对照 (CK) 进行了盆栽试验,设置6个番茄秸秆堆肥与菜园土混配质量占比为0% (T1)、5% (T2)、7.5% (T3)、10% (T4)、12.5% (T5)、15% (T6)。在果实成熟期取样,利用顶空固相微萃取?气相色谱?质谱联用技术 (SPME-GC-MS) 测定番茄果实挥发性物质成分和含量。【结果】7个试验处理的番茄果实共检测出73种挥发性物质,包括9种酮类、25种醛类、19种醇类、5种酯类和4种烃类与11种其他未分类成分,施用堆肥的各处理挥发性物质种类与常规栽培相比差异较大,主要体现在醛类与醇类物质种类上;不同应用配比的堆肥产物对番茄果实挥发性物质含量影响不同,其总含量由高到低依次为T6 > T5 > CK > T4 > T2 > T3 > T1,整体随堆肥产物施用量的增高而增高,其中T5与T6处理的挥发性物质总含量分别较常规栽培番茄提高了81.0%与137%。被检测出的挥发性物质中包含11种番茄特征效应化合物,影响青香、果香与花香这3种类型的香气成分的总含量与挥发性物质总含量高低顺序一致,且T5与T6处理的番茄特征效应化合物总含量分别较常规栽培番茄提高了24.8%与72.2%;T5处理的番茄产量高于T6处理,且与对照无显著性差异。【结论】番茄秸秆经过堆腐处理后作为有机肥料用于番茄生产,不仅可实现番茄秸秆废弃物资源再利用,还可以有效改善番茄的风味品质,使果实香气丰富,果味浓郁。在本试验条件下,将12.5%的番茄秸秆堆肥产物与园土混配 (质量比) 时,番茄果实挥发性物质成分含量显著高于栽培基质对照,且产量与对照无显著差异,是较适宜的掺混比例。     

植物源杀菌包膜复合肥对番茄生长、氮肥利用率及病害的影响

利用植物源杀菌材料作为包衣剂研制出杀菌包膜复合肥, 在番茄小区试验中研究了其杀菌及对番茄生长的影响。结果表明: 各杀菌包膜复合肥处理(分别用ZYF1~ ZYF5 表示)均能有效延缓养分的释放, 与施普通复合肥处理(CK1)相比各杀菌包膜复合肥处理土壤硝态氮在番茄生长后期仍能保持较高含量。除ZYF4 处理外, 其余杀菌包膜复合肥处理番茄产量均明显高于CK1, 其中ZYF3 处理番茄产量最高, 达11.1 kg·m^-2, 较CK1 高16.8%。各杀菌包膜复合肥处理的氮肥利用率也均大于CK1(33.3%), 其中ZYF2、ZYF3 处理分别较CK1 处理高9.9 个和9.5 个百分点。各杀菌包膜复合肥对番茄的Vc 含量无显著影响, ZYF1 处理显著降低了番茄的硝酸盐含量, 而ZYF2、ZYF4、ZYF5 处理则促进了番茄对硝酸盐的累积。各杀菌包膜复合肥处理显著降低了番茄枯萎病、灰霉病的发病率, 其中ZYF1 处理对这两种病菌均有较高的抑制作用, 使发病率较CK1 分别下降17.7 个和12.5 个百分点。     

猪粪和秸秆替代部分化肥提高番茄营养品质及挥发性风味物质种类和数量

  【目的】  研究猪粪和秸秆替代部分化肥对番茄果实营养品质和挥发性风味物质的影响，为番茄优质栽培提供参考。  【方法】  在等氮磷钾条件下，将猪粪 (M)、秸秆 (S) 单独或配合替代化肥中1/4和1/2的氮素。在日光温室进行9年定位试验后，于2018年取番茄果实样品，分析不同施肥处理对果实营养品质、果实中挥发性物质种类和含量的影响。  【结果】  单独施用猪粪或者秸秆替化肥的处理不同程度地降低了番茄果实中果糖、葡萄糖和番茄红素含量，但是对果实中硝酸盐、Vc和可滴定酸含量没有显著影响；秸秆和猪粪配合替代1/2的化肥氮，不会降低果实的营养品质，而且可改善果实的风味。配合猪粪处理的果实中水果香味和花香味的挥发性物质的种类和含量增加，如2-异丁基噻唑、β-紫罗兰酮、3-甲基-丁醇和3-甲基-丁醛、6-甲基-5-庚烯-2-酮；部分风味物质3-甲基-丁醇、6-甲基-5-庚烯-2-酮、3-甲基-丁醛、2-异丁基噻唑、β-紫罗兰酮和E-2-己烯醛含量随着猪粪替代比例的提高呈逐渐增加趋势。  【结论】  在长期等氮磷钾施肥条件下，猪粪和秸秆配合替代1/2的化肥氮素，不会降低番茄的营养品质，还可提高番茄风味品质。猪粪有助于具有水果香味和花香味的挥发性物质在果实内的积累，如2-异丁基噻唑、β-紫罗兰酮、3-甲基丁醇和3-甲基丁醛、6-甲基-5-庚烯-2-酮，且积累量以化肥、猪粪和秸秆配施效果最佳。在30余种挥发性物质中，有12种挥发性物质受不同处理的影响超过预期平均贡献，以E, E-6,10,14-三甲基-5,9,13-十五碳三烯-2-酮和2-甲基-4-戊烯醛最为显著。     

日光温室不同时段补光对番茄果实品质及挥发性物质影响

为探明日光温室中提高番茄产量和品质的最佳补光时段,以"粉太郎"番茄为试材,从植株定植后第25天到第一穗果完全成熟时进行补光,利用LED灯设置3种补光时段:揭帘前补光5 h(T1)、盖帘后补光5 h(T2)、揭帘前盖帘后分别补光2.5h(T3),以不补光作为对照(CK),研究其对番茄产量、果实品质以及挥发性物质成分和含量的影响。结果表明:补光处理可提高番茄平均单株产量、果实可溶性糖含量、可溶性固形物含量、糖酸比、挥发性物质总数量和总质量分数,但会降低有机酸含量,T1处理效果最显著(P<0.05)。4个处理共检测出83种挥发性物质,包括12种酮类、22种醛类、22种醇类、6种酯类、6种烃类和15种其他类物质。各处理挥发性物质总数量和总质量分数由大到小为:T1(68种,3 107.98μg/kg)、T3(65种,2 610.74μg/kg)、T2(63种,2 438.96μg/kg)、CK(59种,2 086.03μg/kg)。每个处理醇类含量最多,烃类含量最低,并且含量最高的物质均是顺-3-己烯-1-醇。3种补光处理均可提高酮类、醛类、醇类和其他类物质含量,但显著降低烃类物质含量(P<0.05),酯类物质含量只在T1处理时有所提高。所有被检测出的挥发性物质包含11种番茄特征香气成分,主要分为花香、果香与青香3种类型,其中青香味物质含量最多。综上,对番茄进行补光尤其是揭帘前补光5 h可有效提高番茄产量、果实品质和风味,是当地日光温室越冬茬番茄栽培的较优补光时段。研究结果可为设施番茄种植的光环境调控技术提供科学依据。     

Effects of abscisic acid and calcium on tomato fruit aroma volatiles

Aroma volatiles are derived from precursors, such as amino acids, fatty acids and carotenoids in tomato fruit. Volatiles enhance the main flavor components in the fruit, particularly sugars. Abscisic acid (ABA) is derived from the carotenoid pathway and there may be an indirect connection to this pathway. Therefore, the purpose of this study was to examine the influence of ABA on tomato fruit volatiles. This study identified five flavor volatile compounds that were consistently present in “Mt. Fresh Plus” tomato fruit tissue. They were 2-methyl furan, (E)-2-hexeanl, 1-hexanol, hexenal, and 6-methyl-5-hepten-2-one. ABA treatments did not have an effect on volatile concentrations in “Mt. Fresh Plus” tomato fruit. Majority of the volatiles identified did not differ between the ABA treated plants and the ABA control plants. However, ABA treatments did significantly decrease (E)-2-hexenal. These results indicated that ABA treatments did not have a major effect on the aroma volatile profile of the fruit.     

Carotenoid pigmentation affects the volatile composition of tomato and watermelon fruits, as revealed by comparative genetic analyses

Tomato near-isogenic lines differing in fruit carotenogenesis genes accumulated different aroma volatiles, in a strikingly similar fashion as compared to watermelon cultivars differing in fruit color. The major volatile norisoprenoids present in lycopene-containing tomatoes and watermelons were noncyclic, such as geranial, neral, 6-methyl-5-hepten-2-one, 2,6-dimethylhept-5-1-al, 2,3-epoxygeranial, (E,E)-pseudoionone, geranyl acetone, and farnesyl acetone, seemingly derived from lycopene and other noncyclic tetraterpenoids. Beta-ionone, dihydroactinodiolide, and beta-cyclocitral were prominent in both tomato and watermelon fruits containing beta-carotene. Alpha-ionone was detected only in an orange-fleshed tomato mutant that accumulates delta-carotene. A yellow flesh (r) mutant tomato bearing a nonfunctional psy1 gene and the yellow-fleshed watermelon Early Moonbeam, almost devoid of carotenoid fruit pigments, also lacked norisoprenoid derivatives and geranial. This study provides evidence, based on comparative genetics, that carotenoid pigmentation patterns have profound effects on the norisoprene and monoterpene aroma volatile compositions of tomato and watermelon and that in these fruits geranial (trans-citral) is apparently derived from lycopene in vivo.     

Application of the porapak q column extraction method for tomato flavor volatile analysis

The Porapak Q column method (PQM) was compared to the method of simultaneous distillation extraction (SDE) under reduced pressure for extraction of the volatile compounds produced by tomato cv. Momotaro. The PQM was found to be effective at trapping and isolating many low and high boiling point volatile compounds and at producing the very desirable natural ripe tomato flavor of extracts. The SDE method was less effective in isolating the higher boiling point volatile compounds and caused deterioration of volatile compounds due to the heating process that takes place during extraction, resulting in an unpleasant boiled green tomato flavor of extracts. The advantages of using the PQM are its simplicity and its high efficiency in isolating many volatile compounds from nonvolatile materials at room temperature. A total of 367 volatile compounds were isolated by the PQM. Of these, hexanal, (Z)-3-hexenal, (E)-2-hexenal, 2- and 3-methylbutanol, and 2-phenylethanol were relatively more abundant than other compounds and (Z)-3-hexenal showed the highest relative amount.     

酸性条件下氮素形态对西红柿根系释放羟基的影响

为研发酸化土壤的生物修复技术,本文用水培实验和电位滴定方法研究了酸性条件下氮素形态对西红柿根系释放羟基的影响,结果表明,在初始pH为4.0、NO3-/NH4+ 比为15:1、5:1、1:1和1:5的营养液中,由于西红柿对NO3--N的偏好吸收导致根系释放羟基,培养液pH升高。培养1周后4个NO3-/NH4+ 比培养液pH分别升高了1.60、1.15、0.57和0.29,与西红柿对NO3--N的吸收量和羟基释放量的大小一致。当西红柿生长在初始pH为5.0营养液中时,仅NO3-/NH4+ 比为15:1和5:1体系中西红柿根系释放羟基,导致培养液pH升高;在NO3-/NH4+ 比为1:1和1:5体系中西红柿根系释放质子,导致培养液pH降低。初始pH5.0条件下西红柿吸收的NO3--N低于初始pH4.0条件下的,其根系释放的羟基量也低于pH4.0体系中的。这些结果说明低pH条件有利于西红柿对NO3--N的吸收,西红柿根系也会释放更多的羟基。因此可以根据西红柿在强酸性条件下对NO3--N的偏好吸收和根系释放羟基的特点对酸化土壤进行生物修复。     

设施栽培番茄的氮磷钾肥料效应研究

采用"3414"肥料试验设计开展了设施栽培番茄的氮、磷、钾肥料效应研究。结果表明,在高肥力土壤上适量施用氮、磷、钾肥均可增加番茄产量,但过量施用会降低其产量;钾肥的增产作用大于磷肥,氮肥的作用较小;氮、钾肥和磷、钾肥配施可增加番茄产量,而氮、磷肥配施降低产量。氮、磷(P_2O_5)和钾(K_2O)最佳经济施肥量分别为119.0、50.4和375.6 kg/hm~2,施肥比例为1∶0.42∶3.16。不同施氮量对番茄硝酸盐和亚硝酸盐含量的影响不规律,增施磷、钾肥番茄硝酸盐含量呈先增加后减少趋势;氮、磷肥和磷、钾肥配施可降低番茄硝酸盐和亚硝酸盐含量。氮、钾肥和磷、钾肥配施提高了番茄可溶性糖含量,氮、磷肥和磷、钾肥配施降低了番茄总酸含量,氮、钾肥配施则有增加番茄总酸含量的趋势,氮、钾肥和磷、钾肥配施均可提高番茄Vc含量。氮、磷、钾肥料合理配施对番茄产量和品质的提高具有重要作用。     

Anionic relationships in leaf petiole sap of tomato and capsicum plants growing in a glasshouse

The nitrate, chloride and sulphate content and their interaction effects in capsicum and tomato plants growing in glasshouse under fertigation systems was studied. Using leaf petiolesap concentrations as an index of the uptake rhythm, it was found that nitrate‐chloride and nitrate‐chloride plus sulphate relationships are regulated by potential or logarithmical laws. Nitrate‐sulphate interactions only appear clear in capsicum plants, but not for tomato.

The utilization of these interaction curves may permit the use of waters with a relatively high saline level for the irrigation of the both capsicum and tomato plants, by suitable planning of the nitrate supply in the fertigation program.     

Nitrogen forms affect root growth,photosynthesis, and yield of tomato under alternate partial root‐zone irrigation

To increase efficiency of water and nitrogen (N) fertilizer use, this study was conducted with a split‐root pot experiment to investigate the effects of different forms of N fertilizer on root growth, photosynthesis, instantaneous water use efficiency (IWUE), and yield of tomato (Lycopersicon esculentum L.) under alternate partial root‐zone irrigation (APRI). Three irrigation modes comprised conventional irrigation (CI) and two kinds of APRI, i.e., APRI with water content in the drying soil compartment controlled at ≥ 60% or 40% of the water‐holding capacity (APRI‐60, APRI‐40). Two N forms included ammonium‐N and nitrate‐N supplied as calcium nitrate or ammonium sulfate, respectively. The results show that APRI‐60 enhanced root growth and increased leaf IWUE with a slight yield reduction compared with CI regardless of the N form supplied. In contrast, APRI‐40 significantly decreased root growth and inhibited photosynthesis, thereby resulting in a significant yield loss. In addition, at the flowering stage tomato plants grew better with ammonium‐N than nitrate‐N supply; however, at the fruit expansion stage and maturity stage, the tomato plants had a higher biomass accumulation and yield with nitrate‐N than ammonium‐N supply. Therefore, the application of APRI should consider the soil water condition coupled with an appropriate N form. In the present study, APRI controlled at ≥ 60% of the water‐holding capacity (WHC) for the drying soil side with nitrate‐N supply was the best water‐fertilizer supply for tomato cultivation.     

腐植酸对番茄苗期氮素代谢的影响

腐植酸对肥料具有改性增效的作用,以番茄为供试材料,研究腐植酸增效剂不同添加量对番茄苗期生长及氮素代谢酶活性的影响,为腐植酸的开发应用提供参考依据。采用砂培试验方法,设置了向霍格兰营养液分别加入腐植酸增效剂0(HA0),1(HA1),2(HA2),5(HA3),10(HA4) mL/L处理。培养30天后,测定番茄的生长指标、植株养分含量、硝酸还原酶活性、谷氨酰胺合成酶和谷氨酸脱氢酶活性。添加适量腐植酸增效剂能促进番茄苗期生长,HA3处理番茄根系干重比HA0提高了31.68%,HA1处理番茄地上部干重最大。添加腐植酸可以提高番茄苗期叶片叶绿素含量,HA3处理番茄苗期叶片叶绿素总量和类胡萝卜素含量最高,分别比HA0提高了17.11%,24.04%。添加适量腐植酸增效剂能增加番茄苗期根系和地上部对氮素的吸收,HA3处理的番茄根系、地上部及总氮素积累量比HA0分别提高了30.61%,20.24%,21.54%。添加腐植酸增效剂可以调控番茄根系和叶片氮素代谢过程,提高了氮素代谢酶活性,与HA0相比,HA4处理根系硝酸还原酶活性最大,HA3处理根系谷氨酰胺合成酶活性最高,HA2处理根系谷氨酸脱氢酶的活性最大;HA3处理番茄苗期叶片中硝酸还原酶、谷氨酰胺合成酶和谷氨酸脱氢酶活性最大,与HA0处理相比分别提高了38.27%,64.54%,106.63%。添加腐植酸增效剂可以促进番茄苗期的生长和对氮素的吸收,提高氮素代谢酶活性,处理中以在营养液中添加5 mL/L腐植酸增效剂效果最佳,腐植酸增效剂添加量低于5 mL/L时,对番茄苗期的生长及氮素代谢具有明显的促进作用。     

Effect of overexpression of fatty acid 9-hydroperoxide lyase in tomatoes (Lycopersicon esculentum Mill.).

To modify the flavor properties of tomato fruits, cucumber fatty acid hydroperoxide lyase (HPL), which can act on 9-hydroperoxides of fatty acids to form volatile C9-aldehydes, was introduced to tomato plants. Through enzyme assay, high activity of the introduced HPL could be found in either the leaves or fruits of transgenic tomatoes; however, the composition of volatile short-chain aldehydes and alcohols in the transgenic tomato fruits was little modified. This was unexpected because tomato fruits have high lipoxygenase activity to form 9-hydroperoxides. When linoleic acid was added to a crude homogenate prepared from the transgenic tomato fruits, a high amount of C9-aldehyde was formed, but the amount of C6-aldehyde was almost equivalent to that in nontransgenic tomatoes. Through quantification of fatty acid hydroperoxides, it has been revealed that 13-hydroperoxides of fatty acids are preferably formed from endogenous substrate, whereas 9-hydroperoxides are formed from fatty acids added exogenously. From these observations, possible mechanisms to regulate metabolic flow of the lyase pathway are discussed.     

移栽定殖根际有益菌番茄苗的田间效应研究

为评估移栽定殖根际有益菌(PGPR)番茄苗对果实产量和青枯病防控效果的影响,通过连续3季田间试验,研究了基于生物有机肥的施用,移栽生物育苗基质(在普通育苗基质中添加分离自根际的解淀粉芽孢杆菌)所育种苗(BIONS),相比于移栽普通育苗基质所育种苗(BIO),对设施番茄产量、发病率、收获期植株土体与根际微生物数量和土壤基本理化性质的影响。连续3季田间试验结果表明:相比于BIO处理,BIONS处理第一、二、三季的增产幅度分别达38.86%、47.87%、34.60%,产量差异均达到显著性水平;BIONS处理的发病率每季均极显著低于BIO处理;BIONS处理增加了根际细菌数量,降低了根际真菌数量;土壤基本理化性质方面,BIONS处理的硝态氮含量和铵态氮含量每季均高于BIO处理,且硝态氮含量与产量呈显著正相关,硝态氮含量和铵态氮含量与发病率呈显著负相关。因此,以生物有机肥为底肥,移栽生物育苗基质所育种苗,能够有效防控番茄青枯病的发生,进而提高产量。     

Quantitation of free and glycosidically bound volatiles in and effect of glycosidase addition on three tomato varieties (Solanum lycopersicum L.)

The volatile fractions of three tomato cultivars (p73, Jorge, and Durinta) were studied in both free and glycosidically bound forms. The possibility of increasing the concentration of free volatile compounds by adding selected glycosidases was also tested. The free volatile fraction (FVF) of tomato juice was directly determined by headspace solid-phase microextraction (SPME). To analyze the glycosidically bound fraction (GBF), tomato juice samples were extracted with C18 cartridges and the resulting glycoside extracts were enzymatically hydrolyzed. The released aglycons were determined by headspace SPME. Of these compounds, six were not previously reported to belong to the tomato GBF. The concentration of 21 of 24 compounds detected in the FVF was significantly different between cultivars, the majority of them being greater in p73 than in Durinta and Jorge cultivars. In the GBF, 19 of 26 compounds that were detected were significantly different between cultivars but only the amount of trans-linalool oxide was significantly the greatest in the p73 cultivar. The addition of Candida molischiana beta-glucosidase (BGLN) and Saccharomyces cerevisiae exoglucanase (EXG1) to tomato juice samples led to increases in the concentration of 10 compounds, with variations depending on the cultivar or enzyme. These results provide scientific support for using glycosidases as a tool to improve tomato aroma.     

Boron Toxicity Alters Nitrate Reductase Activity,Proline Accumulation,Membrane Permeability,and Mineral Constituents of Tomato and Pepper Plants

ABSTRACT

Boron (B) toxicity is an important disorder that can limit plant growth on soils of arid and semi arid environments throughout the world. Although of considerable agronomic importance, our understanding of B toxicity is rather fragmented and limited. The effects of increasing levels of B (0, 0.5, 5, 50 mg kg^{? 1}) on plant growth, proline accumulation, membrane permeability, nitrate reductase activity (NRA), and mineral nutrient interactions of tomato and pepper plants were investigated in greenhouse conditions. Increasing levels of B increased the B contents of plants. Boron toxicity symptoms occurred at 5 and 50 mg kg^{? 1} levels. Fresh and dry weights of the plants clearly decreased with the application of the 50 mg kg^{? 1} level of B. Membrane permeability and proline accumulation were significantly increased by the 50 mg kg^{? 1} level of B. Nitrate reductase activity of tomato plants was increased with increasing levels of B. With the exception of potassium (K) and calcium (Ca) in pepper and magnesium (Mg) in tomato, B treatments significantly affected nutrient concentrations of tomato and pepper. Except for sulfur (S) and Ca in tomato, the highest rate of B applied increased the N, phosphorus (P), and K concentrations of tomato and N, P, Mg, and S concentrations of pepper.     

Nitrogen Metabolism and Tomato Yield in Response to Organic Fertilization

We assessed the effects of organic fertilization on the response of biochemical and physiological indicators and the yield of saladette-type tomato (Solanum lycopersicum L.) grown under greenhouse conditions. Five fertilization forms [sand + inorganic nutrient solution (F1); sand + vermicompost tea (F2); a mixture of sand, compost, + vermicompost tea (F3); a mixture of sand, vermicompost, + vermicompost tea (F4); and a mixture of sand, compost, vermicompost, + vermicompost (F5)] and two genotypes (Cuauhtémoc and El Cid) were evaluated. The parameters analyzed were leaf pigments, enzymatic activity of nitrate reductase (NR) in vivo, and yield. A fertilizer source of sand + vermicompost tea resulted in the best assimilation of nitrate (NO₃-), the greatest NR endogenous activity, the second highest foliar concentration of organic nitrogen (N), and the second best yield. In conclusion, for improved tomato cultivation during organic production, treatment F2 produced the maximum organic yield and resulted in more efficient N utilization.     

Effects of nitrogen application on flavor compounds of cherry tomato fruits

A pot experiment was conducted to determine the effects of N application on volatile compounds, taste compounds, and firmness of fresh tomato fruits. Each pot was filled with 8 kg of clean sand. The experiment consisted of six nitrogen (N)‐application rates with 0, 2.25, 4.50, 9.00, 18.00, and 36.00 mmol N L^–1 in the nutrient solution. Volatile compounds, soluble sugars, soluble solids, titratable acidity, and firmness of fresh tomato fruits were measured. The results show that increasing N application increased the concentrations of 1‐penten‐3‐one, hexanal, cis‐3‐hexenal, 2‐methyl‐4‐pentenal, trans‐2‐hexenal, 6‐methyl‐5‐hepten‐2‐one, titratable acidity, soluble sugars, and soluble solids. By contrast, increasing N supply decreased the concentration of phenylacetaldehyde and first increased and then decreased the concentrations of 2E–4E‐hexadienal and the firmness of fresh tomato fruits. Close relationships between the concentration of various volatile compounds, titratable acidity, soluble sugars, and soluble solids were found. However, concentrations of these flavor compounds were very poorly correlated with fruit firmness. Based on contributions of these compounds to tomato flavor, we assume that moderate high N supply improves tomato flavor, whereas excessive N supply can deteriorate it.     

日光温室秋冬茬番茄氮素供应目标值的研究

通过连续两年的田间试验,以寿光当地的传统施肥处理为对照,通过对日光温室秋冬茬番茄主要生育时期土壤无机氮素供应水平的调控,确定番茄在第一穗果膨大期、第二穗果膨大期和第四穗果膨大期合理的无机氮素供应水平(追肥前根层土壤Nmin+追施化肥氮量)分别为N237、173和153kg/hm2。在3次追肥期间土壤有机氮矿化数量分别为N53、13和21kg/hm2;有机肥矿化提供的氮素量分别为N41、8和-17kg/hm2;灌溉水带入氮素量分别为N11、5和5kg/hm2。因此,若考虑土壤Nmin、土壤有机氮矿化、有机肥矿化、化肥氮及灌溉水带入的氮素等来源的氮素供应,则日光温室秋冬茬番茄在第一穗果膨大期、第二穗果膨大期和第四穗果膨大期时的氮素供应目标值分别为N342、199和162kg/hm2。目标产量为73t/hm2的番茄全生育期的氮素供应目标值为N481kg/hm2。     

水氮耦合供应对温室番茄果实硝酸盐累积的影响

采用2水平灌水量(W1:4541.0、W2:2270.6 m3/hm2)×3水平氮肥追施量(N1:747.4、N2:373.7及N3:0 kg/hm2),研究了不同灌溉、施氮量对日光温室番茄果实硝酸盐累积的影响。结果表明,番茄果实硝酸盐含量随果实成熟度的提高而降低、随结果部位的提高而提高。水氮耦合供应可以显著影响番茄果实中硝酸盐含量。在施氮量相同的情况下,果实硝酸盐含量随着灌水量的增加而降低;而在灌水量相同的情况下,果实硝酸盐含量随施氮量的增加而增加。