Effect of slow-release oxygen supply by fertigation on horticultural crops under soilless culture

Oxygen deficiency has an immediate effect on both water and nutrient uptake, the yield of the whole plant under different soilless culture is affected. The oxygen level required for the respiration of the root system then becomes a limiting factor as much in soil culture as in soilless culture. The total area of soilless crops in SE Spain today is estimated to be about 5000 ha. The objective of this experiment was to study the effect of potassium peroxide as an oxygen generator on vegetable crops growing in commercial substrates and to determinate the supply fraction for its use. Bioassay was used to determinate the fraction of potassium peroxide needed. Three greenhouse experiments were conducted in soilless culture with perlite and rockwool. Sweet pepper, melon and cucumber crop were supplied with potassium peroxide through fertigation to increase the oxygen content for one day per week. There were treatments: one with (T1) and the other without potassium peroxide (T0) in the nutrient solution. Fertigation parameters, yield and its quality were measured. Bioassay suggested that one gram per litre is the best fraction to use in soilless culture. Yield of sweet pepper was about 20% higher for T1 than T0 and 15% for melon; there was no significant difference in cucumber plants.     

Soilless systems as an alternative to wild strawberry (Fragaria vesca L.) traditional open-field cultivation in marginal lands of the Tuscan Apennines to enhance crop yield and producers’ income

Yield and quality of wild strawberry (Fragaria vesca L.) cultivars ‘Regina delle Valli’ and ‘Alpine’ cultivated in soil, as the traditional production system, and in soilless (both in open air and protected environments), as an innovative and sustainable production system, were investigated in a marginal and inner area of the Pistoiese Apennine Mountains during two production seasons. An earlier marketable production was obtained in soilless culture, but total marketable yield was higher from plants grown in a traditional open-field environment. Fruits obtained from the protected soilless system were larger, but developed some mildew, had some visual defects, and revealed a reduced skin chroma index, flesh firmness, and total soluble solids content compared to fruits harvested from plants grown under direct sunlight, while no significant differences were observed in total titratable acidity and pH between growing systems. ‘Alpine’ was more suited to soilless protected cultivation, with a much higher yield compared to ‘Regina delle Valli’. Physicochemical properties of berries were not affected by the cultivar, but fruit quality changed with plant age and seasonal crop cycle. ‘Alpine’ fruits gained a greater sensorial preference, both in traditional soil and soilless culture.     

菌渣与河沙不同配比对番茄栽培的影响

试验利用菌渣和廉价的河沙以不同比例配制混合基质进行番茄无土栽培,以期筛选出利用菌渣与河沙混合基质栽培番茄的最佳配比。试验结果表明,菌渣可以促进番茄植株的生长,加速根系发育,改善果实品质,以菌渣与河沙混合作为无土栽培基质明显优于传统的土壤栽培方法,其中,以菌渣∶河沙=8∶2的处理效果最好。     

Influence of Different Soilless Substrates to Morpho-physiological Characteristics and Yield Relations in Strawberries

Some of the advantages of soilless production systems over conventional systems are higher yield, better pest control management and more efficient labor use. Among berries, strawberry responds quite well to soilless production systems. Major yield-affecting factors for strawberries in soilless systems may be listed as; growing medium, source and types of plantlets, density of plants and efficiency of fertigation system. The present research was conducted with strawberry plants (Fragaria x ananassa ‘Camarosa’) grown in four different media; (1) Cocopeat (C), (2) Peat (P) and (3 and 4) 1:1 mixtures with Pumice (Pu), to evaluate the effects of soilless media on marketable yield and root-shoot morpho-physiological parameters. Correlation measurements were made to assess if there is any interaction between yield and any tested morpho-physiological feature. The experiment was conducted in greenhouse, using frigo plantlets (11.6 plantlet/m²) planted in July and through 1 June of following year. Results showed that growth medium had an effect on yield, numbers of developed leaves, shoot-root dry mass, number and length of roots. Yield was correlated with these morphological features. Growth medium also had an influence on plant nutrient accumulations i.?e., shoot accumulation of nitrogen (N) and potassium (K) and root accumulation of phosphorus (P) and all the micro-nutrients that with exception of boron (B). There were some interactions between yield and plant nutrient content of tissues determined by correlation analyses. The most striking were negative correlations with yield and shoot N–K amounts and positive correlation with yield and root P amount. Some positive correlations were also found between yield and copper (Cu), manganese (Mn) and zinc (Zn) contents of both shoot and root tissues. Boron (B) contents was correlated only with the root tissues. The medium which had the best overall performance for soilless strawberry production was C?+?Pu and should be recommended to be used with frigo plantlets of ‘Camarosa’.     

Using mini-rockwool blocks as growing media for limited-cluster tomato production

Rockwool is an excellent growing medium for the hydroponic production of tomato; however, the standard size rockwool blocks [4 x 4 x 2.5 inches (10 x 10 x 6.3 cm) or 3 x 3 x 2.5 inches (7.5 x 7.5 x 6.3 cm)] are expensive. The following experiments were conducted with less expensive minirock wool blocks (MRBs), on rayon polyester material (RPM) as a bench top liner, to reduce the production cost of tomatoes (Lycopersicon esculentum) grown in a limited-cluster, ebb and flood hydroponic cultivation system. Fruit yield for single-cluster plants growing in MRBs [2 x 2 x 1.6 inches (5 x 5 x 4 cm) and 1.6 x 1.6 x 1.6 inches (4 x 4 x 4 cm)] was not significantly different from plants grown in larger sized blocks (3 x 3 x 2.5 inches). When the bench top was lined with RPM, roots penetrated the RPM, and an extensive root mat developed between the RPM and the bench top. The fruit yield from plants on RPM was significantly increased compared to plants without RPM due to increases in fruit size and fruit number. RPM also significantly reduced the incidence of blossom-end rot. In a second experiment, single- and double-cluster plants were grown on RPM. Fruit yield for double-cluster plants was 40% greater than for single-cluster plants due to an increase in fruit number, although the fruit were smaller in size. As in the first experiment, fruit yield for all plants grown in MRBs was not significantly different from plants grown in the larger sized blocks. MRBs and a RPM bench liner are an effective combination in the production of limited-cluster hydroponic tomatoes.     

Response of some horticultural crops to irrigation in the semi-arid region of Tunisia

Response to a limited water supply was determined for 3 horticultural crops, pepper, melon (cantaloup) and tomato, in the Nebhana Valley, Tunisia. Varying fractions of potential evapotranspiration (PET), as calculated by Penman, were used to define 4 irrigation treatments which were replicated 4 times. The study was conducted on a shallow sandy loam soil in the lower Nebhana Valley, near Monastir. For each of the crops the following production parameters were evaluated: marketable yield; average fruit weight; number of fruits per unit land area. For socio-political reasons, the cost price of the irrigation water to the farmers in the Nebhana Valley is of negligible importance, and thus the economic threshold could be drawn from the relationship between yield and total available water. The marketable yield for pepper, melon and tomato crops was not significantly affected by rationing the seasonal water application volumes to 57, 47 and 67%, respectively, of the calculated PET. To increase the water-use efficiency for the crops studied, limited irrigation is advisable.     

中药渣有机基质对番茄产量和品质的影响

以中药厂废渣为原料制成的中药渣有机基质添加不同比例的无机基质,进行番茄无土栽培试验.结果表明:与对照土壤栽培相比,75%中药渣+10%蛭石+15%珍珠岩能显著提高番茄的产量.通过营养分析得知,中药渣有机基质能提高番茄果实的Vc含量、茄红素含量和可滴定酸含量,从而改善番茄果实品质.综合中药渣有机基质对番茄产量和果实品质的影响发现,75%中药渣+10%蛭石+15%珍珠岩是最适合番茄生长的中药渣有机基质配比.     

复混基质对南疆日光温室番茄根区环境、果实品质及产量的影响

以粗砂、蛭石、菇渣、树叶、锯末为基质材料,不同材料按体积比复配后形成10种复混基质,以粗砂基质为对照,进行"欧曼"品种番茄栽培试验。采用相同尺寸栽培槽填充基质、无土栽培水肥管理及田间整枝管理措施,研究了不同配比基质理化性质、根区温度与根区湿度,及其对番茄果实品质及产量的影响。结果表明:复混处理后基质的容重较CK显著降低,孔隙度较CK显著升高;复混基质能改善根区的温湿环境,不同处理平均温度较CK提高了0.35~1.24℃,平均湿度较CK提高1.86%~13.32%;对比果实产量和品质发现T6与T8处理总体表现最好,果实硬度、单果质量、单株产量、单株结果数、增产率均优于其它处理,维生素C、可溶性蛋白质、有机酸含量也均处于较好水平,综合比较发现T6处理(粗砂∶蛭石∶菇渣∶树叶∶锯末=2.5∶2.5∶1∶2∶2)和T8处理(粗砂∶蛭石∶菇渣∶树叶∶锯末=2.5∶2.5∶1∶1∶3)能为番茄生长提供良好生长环境,并能提高番茄的产量及品质。     

Growth,yield, fruit quality and nutrient uptake of hydroponically cultivated zucchini squash as affected by irrigation systems and growing seasons

Zucchini plants (Cucurbita pepo L.) were grown in closed soilless systems to analyze the effects of two of the most promising and used irrigation systems (drip and subirrigation) and two cropping seasons (spring-summer and summer-fall) in terms of substrate EC, growth, yield, fruit quality (dry matter, carbohydrates, protein, Vitamin C, nitrates and mineral composition), total nutrient uptake, mineral solution composition and water use efficiency (WUE). Plants grown with subirrigation had a high electrical conductivity in the upper and lower layers of the pots in both growing seasons, especially in the spring-summer season. In the spring-summer season, zucchini yield (total and marketable) was 18% lower with the subirrigation than with the drip-irrigation system, but the fruit quality was higher (dry matter, glucose and fructose concentrations), while no significant difference of total and marketable yield were recorded between irrigation systems during summer-fall season. In both growing seasons, and after 76 days of solution recycling, the variation of nutrients (N, P, K, Mg and Na) in the solution composition at the end of the experiment was lower with the subirrigation than with the drip-irrigation systems. Compared with the spring-summer season, plants grown in the summer-fall season exhibited a 35 and 33% lower total and marketable yield, respectively, but offer several benefits: earlier production (10 days), and higher fruit quality (higher concentration of glucose, fructose, sucrose, starch, P, K, and Mg), and water use efficiency. To produce 1 kg of marketable fruits 29 L of nutrient solution were necessary in the summer-fall season and 42 L in the spring-summer season. From an environmental point of view, growing zucchini during the summer-fall season represents an important practice to improve WUE especially in areas where water conservation is a concern.     

The influence of growing season on fruit yield and quality of greenhouse melon (Cucumis melo L.) grown in nutrient film technique in a Mediterranean climate

Summary

The influence of growing season on some physiological and biochemical variates related to fruit yield and quality was investigated in melon (Cucumis melo L.) plants cultivated in nutrient film technique in a greenhouse located at Pisa, Central Italy, from mid-March to mid-June, or from mid-July to mid-September. Compared with spring, the plants grown in summer exhibited faster growth and development, but produced fewer fruits of larger size and poorer quality due to reduced sucrose content. Growing season did not affect total leaf area, but dry-matter production and partitioning to the fruits was significantly lower in summer than in spring. Summer fruit ripened within 30–35 d after anthesis, about 14 d fewer than in spring. Higher average temperature was presumably responsible for earlier fruit maturation in summer, as in both seasons all melons were harvested after 450–500 degree-days (base temperature of 12°C) from anthesis. Fruit swelling did not account for the reduction of sucrose content in summer-grown fruits, which instead was due to shortage of photoassimilate supply and inadequate sucrose synthesis, as suggested by the rate of leaf gas exchange and the activity of sucrose phosphate synthase in the fruit flesh, as determined during the final stages of fruit development. Lower solar radiation was presumably responsible for the reduced leaf carbon assimilation in summer, as growing season did not affect leaf turgor, stomatal conductance, mineral status and chlorophyll content.     

Responses of field grown tomato plants to arbuscular mycorrhizal fungal colonization under varying intensities of drought stress

The effects of root colonization by the arbuscular mycorrhizal (AM) fungus Glomus intraradices Schenck and Smith on growth, flower and fruit production, and fruit quality were studied in field-grown tomato plants exposed to varying intensities of drought stress. Inoculated (M+) and non-inoculated (M−) tomato seedlings were exposed to varying intensities of drought stress by adjusting irrigation intervals. Mycorrhizal plants had significantly higher uptake of N and P in both roots and shoots regardless of intensities of drought stress. AM inoculation also significantly increased shoot dry matter and the number of flowers and fruits. The fruit yields of M+ plants under severe, moderate, mild drought-stressed conditions were higher than M− plants by 24.7%, 23.1%, 16.2% and 12.3%, respectively. Furthermore, M+ plants produced tomato fruits that contain significantly higher quantities of ascorbic acid and total soluble solids (TSS) than M− plants. Mycorrhizal effects increased with increasing intensity of drought. The overall results suggest that mycorrhizal colonization affects host plant nutritional status, water stratus and growth under field conditions and thereby alters reproductive behaviour, fruit production and quality of fruits under both well-watered and drought-stressed conditions.     

有机生态型无土栽培技术及其营养生理基础

以番茄为试材,介绍了应用消毒有机肥代替营养液的有机生态型无土栽培技术的方法与原理。1991～1994年的试验结果表明:与营养液栽培相比,有机生态型无土栽培方法可降低肥料成本、增加果实中还原糖和维生素C含量、降低有机酸含量;采用有机生态型无土栽培,在番茄的整个生长期间,基质中营养元素的供应水平与植株对营养元素的吸收要求一致,吸收氮、磷、钾的比例为N:P2O5:K2O=1:0.251:1.141;同时,有机生态型无土栽培对环境无污染。     

Effects of auxin application on fruit formation in tomato growing under stress temperatures in the field

Summary

Tomato (Lycopersicon esculentum L. Mill) cultivars Early Urbana and Red Clode were grown in the field at adverse temperatures (stress regimes) until they set fruit in two growing seasons (Autumn and Spring) during 1999 and 2000 in Ahwaz (Southern Iran). To test the effectiveness of auxins in enhancing fruit set, racemes of tomato were sprayed during early fruit set with 25, 50 and 100 mg l^–1 4-chlorophenoxy acetic acid (4-CPA) and indole-3-butyric acid (IBA) followed by two additional applications at three intervals. The control plants were treated with deionized water. At harvest, racemes from autumn and spring plantings that were treated with 4-CPA had more large fruits than the control racemes. In both growing seasons, neither cultivar showed a significant difference in fruit set in plants treated with IBA, compared with controls. The ratio of fruit/flower in all racemes treated with 4-CPA increased significantly compared with the other treatments. However, auxin treatments did not significantly affect the number of flowers per raceme. Plants treated with 4-CPA produced the highest yield of marketable fruit. The greatest increase in total yield and parthenocarpic fruit occurred with 4-CPA treatments. Also, there was little difference between concentrations of 4-CPA on fruit set in both cultivars. It may be concluded that the response of fruit setting in tomato to either low or high temperatures regimes was auxin dependent and that 4-CPA was more effective than IBA.     

沼渣混配基质对黄瓜和番茄生长、产量及品质的影响

为实现固体废弃物资源化应用,减少无土栽培基质生产成本,以黄瓜和番茄为试验材料,将沼渣、醋糟、蛭石按一定比例混配,研究混配基质在黄瓜和番茄育苗与栽培中的应用效果。试验结果表明,混配基质T_4(沼渣∶醋糟∶蛭石=4∶4∶2)黄瓜出苗率、壮苗指数、根系活力等均较高,分别比对照增加了7.95%、17.65%和32.14%;混配基质T_6(沼渣∶醋糟∶蛭石=2∶6∶2)番茄出苗率、株高、茎粗、根系活力、壮苗指数等高于其他处理。另外,混配基质T_4黄瓜和番茄叶绿素含量和光合速率较高,产量、可溶性糖、可溶性蛋白及维生素C含量最高。综上所述,沼渣混配基质T_4和T_6可分别作为黄瓜和番茄育苗基质,获得优质壮苗;沼渣混配基质T_4可作为黄瓜和番茄栽培基质。     

塑料大棚无土栽培高品质番茄品种筛选

为筛选出适宜京郊塑料大棚无土栽培的高品质番茄品种,对引进的6个高品质番茄品种的生育期、植株和果实性状、果实口感、商品果产量等指标进行比较分析。结果表明：京采8号、高糖102番茄果实总糖含量分别达到8.23%、6.13%,糖酸比达到8.12、6.93,果实沙甜,口感较好。除去因脐腐果等丧失商品性的果实,京采8号、高糖102折合667 m²商品果产量分别达到1 883.4、2 307.6 kg,表现突出,适宜在京郊进一步示范种植。     

曼陀罗嫁接番茄抗温室根结线虫病研究

以曼陀罗做根砧进行了温室番茄嫁接抗根结线虫病的研究.结果表明:曼陀罗与番茄具有良好的亲合性,嫁接后植株生长势和抗根结线虫能力增强,产量提高,果实无毒,口感同自根苗番茄无明显差别.     

配方施肥对基质栽培樱桃番茄产量、品质和环境的影响

采用有机肥配方施肥和常规营养液基质栽培樱桃番茄的试验结果表明：采用鸡粪＋花生麸、鸡粪＋ 茶麸和鸡粪＋ 花生麸＋ 茶麸等有机肥的配方施肥,可提高樱桃番茄产量、改善品质、降低成本并增加收入;纯鸡粪处理较对照减产,鸡粪加少量复合肥则增产增收。鸡粪＋ 茶麸处理的灌溉排出液硝酸盐含量低,对环境无污染。     

京郊风味甜瓜整枝留果方式探索试验

为提高风味甜瓜的产量,以"帅果7号"为试验材料,采用随机区组试验方法,设置单蔓整枝留1果、单蔓整枝留2果、双蔓整枝留2果3个处理,研究不同整枝及留果方式对风味甜瓜生长、产量和品质的影响.结果表明:风味甜瓜单蔓整枝留1果和双蔓整枝留2果效果均佳,果实大小适中,果形周正,果实含糖量以单蔓整枝留1果处理最佳,667 m2产量...     

Essential and non-essential element composition of tomato plants fertilized with poultry manure

Poultry manure (PM) must be disposed of from poultry farms, but is a potentially valuable source of macro- and micronutrients for plant growth. The objective of this study was to examine the effects of poultry manure on the growth of tomato (Lycopersicon esculentum) plants. Yields of fruits and vegetative material of plants grown in soil with 0, 10, 20 and 40 g kg⁻¹ PM added were measured. Concentrations of N, P, K, Ca, Mg, S, Fe, Zn, Cu, Mn, Mo, Cl, Si, Br, Rb, Sr and Ba in leaves at flowering and at final harvest and in fruits were determined by polarized energy dispersive X-ray fluorescence (PEDXRF). Poultry manure fertilization improved tomato shoot growth and also fruit yield and increased leaf N concentrations at the harvest stage. In addition, P concentrations of the leaves and fruits were increased as the application rate of PM was increased. Fruit Ca and Mg were significantly reduced by increased rate of PM application, but not to the extent to cause the calcium deficiency disorder blossom end rot. Applied high levels of PM slightly increased the concentrations of leaf Mo and Br at the harvest stage. Poultry manure applications had a positive effect on the concentrations of leaf Zn, Cu, Cl and Rb at both sampling stages, but leaf Si concentration was reduced by PM treatments. The concentrations of Zn and Rb were increased in the fruits by PM treatments, but the concentrations of Br were decreased. Applied PM levels had no significant effects on the concentrations of K, S, Fe, Sr or Ba in tomato plants. It is concluded that the increased fruit yield, and the increased concentration of Zn (an element required in the human diet) and the lowered concentration of potentially harmful Br in the fruit make poultry manure a valuable growing medium for tomato production.     

Photosynthetic parameters and cut-flower yield of rose ‘Eurored’ (H.T.) are adversely affected by mild water stress irrespective of substrate composition

The aim of the present study was to provide a better insight into the adaptive processes within rose plants ‘Eurored’ (Hybid Tea), grown in soilless cultivation, when exposed to water deficit. Rose plants were grown in three different substrates (perlite, pine bark–almond shells 1:1, and perlite–pumice 1:1) and under two water regimes (100 and 67% of the irrigation needs). Photosynthetic parameters, water relations, leaf chlorophyll content, chlorophyll fluorescence and cut-flower production were determined.