Search

Relevance and methods. Pumpkin fruits and seeds are valuable raw materials for the food and pharmaceutical industries. Of particular value are pumpkin seeds, from which oil and protein products are obtained. The purpose of our research is to identify the best breeding samples of pumpkin in terms of seed yield and pumpkin oil and to study their biochemical composition. The evaluation of 12 samples of pumpkin was carried out according to the main economic and biological characteristics. Results. According to the yield of seeds and the yield of pumpkin oil, the following samples were distinguished: Delta, Golosemyanno-kustovaya, Line 2-3, Line 2-5. The biochemical composition of seed samples with high seed yields was studied in terms of the content of proteins, fats, carbohydrates, amino acids, fatty acids, vitamins and minerals. A biochemical analysis of pumpkin seed oil for fatty acids, sterols and minerals was carried out. Seeds of hard-barked pumpkin of Belarusian selection are sources of high protein content (34-35%) with a wide range of essential amino acids, fats (43-45.8%), unsaturated and saturated fatty acids, as well as carbohydrates (9.6-11.9%) , a number of vitamins, macro- and microelements.

The use of organic substances in integrated pest management can contribute to human- and environment-safe crop production. In the present work, a combination of organic biostimulants (Fullcrhum Alert and BioVeg 500) and an inorganic corroborant (Clinogold, zeolite) was tested for the effects on the plant response to the quarantine pest tomato leaf curl New Delhi virus (ToLCNDV). Biostimulants were applied to healthy and infected greenhouse-grown zucchini plants, and the vegetative parameters and viral titer were evaluated. Although no antiviral effects were observed in terms of both virus replication and symptom expression, these biostimulants were shown to influence plant fitness. A significant increase in biomass and in leaf, flower, and fruit production was induced in both healthy and infected plants. Biostimulants also enhanced the production of metabolites commonly involved in plant response to virus infection, such as carbohydrates, phenylpropanoids and free amino acids. These results encourage new field trials to evaluate the actual productivity of infected plants after treatments and the possible application of organic biostimulants in agriculture.

The objective of this study was to analyse the effect of freezing and different culinary treatments (stir-fried and steamed) on the nutritional composition, bioactive compounds and the sensorial characteristics of zucchini. The zucchini was stir-fried for 8 minutes at 250ºC and steamed for 13 minutes at 100ºC. The freezing of raw zucchini does not significantly affect its nutritional compounds. The stir-frying process provoked important moisture loss; this being higher is zucchini that were previously frozen. The content of ash, proteins and fats, significantly increased in stir-fried zucchini. There was an important decrease in antioxidant activity and phenolic compounds when the zucchini was frozen. The antioxidant activity was much greater in the stir-fried produce in comparison to steamed and raw. Freezing the raw zucchini provoked a significant loss in its adhesiveness qualities and hardness. A lower hardness and adhesiveness was also observed in frozen zucchini after steamed and stir-fried, with these changes not being observed in freezing. The sensorial characteristics of previously frozen zucchini were valued less by the consumer as well as those that were steamed and stir-fried. The culinary treatment had less influence its sensorial values, only better valuations were observed in fresh steamed zucchini than the stir-fried. Ciencias de la Alimentación

This research was carried out aiming at evaluating the effects of nitrate and ammonium ions on nutrient accumulation, biochemical components and yield of Italian zucchini (cv. Caserta) grown in a hydroponic system under salt stress conditions. The experiment was carried out in a greenhouse utilizing an experimental design in randomized blocks, arranged in a 2 x 5 factorial scheme, with 4 replications. The treatments consisted of two forms of nitrogen (nitrate - NO3- and ammonium - NH4+) and 5 electrical conductivity levels of irrigation water (ECw) (0.5, 2.0, 3.5, 5.0 and 6.5 dS m-1). The analysis of the results indicated that supply of N exclusively in NH4+ form promotes greater damage to the leaf membrane and reduction in accumulation of macronutrients and higher Na+/K+, Na+/Ca++ and Na+/Mg++ ratios in the shoots of zucchini plants. Electrical conductivity of irrigation water above 2.0 dS m-1 reduces the accumulation of nutrients in shoot and yield of Italian zucchini plant. The toxicity of NH4+ under Italian zucchini plants overlap the toxicity of the salinity, since its fertilization exclusively with this form of nitrogen inhibits its production, being the NO3- form the most suitable for the cultivation of the species. Resumo Este trabalho foi desenvolvido com o objetivo de avaliar os efeitos dos íons nitrato e amônio sobre o acúmulo de nutrientes e produção da abobrinha italiana (cv. Caserta) cultivada em sistema hidropônico sob estrese salino. O experimento foi conduzido em casa de vegetação utilizando o delineamento experimental em blocos casualizados, arranjados em esquema fatorial 2 x 5, com 4 repetições. Os tratamentos foram constituídos de duas formas de nitrogênio (nitrato - NO3- e amônio - NH4+) e cinco níveis de condutividade elétrica da água de irrigação (CEa) (0,5; 2,0; 3,5; 5,0 e 6,5 dS m-1). As análises dos resultados indicaram que suprimento de N exclusivamente em forma de NH4+ promove maiores danos na membrana foliar e redução no acúmulo de macronutrientes e maiores relações Na+/K+, Na+/Ca++ e Na+/Mg++ na parte aérea das plantas de abobrinha. A irrigação com água a cima de 2,0 dS m-1 reduz o acúmulo de nutrientes na parte aérea das plantas e a produção de abobrinha. A toxicidade do NH4+ sob abobrinha italiana sobrepõe-se à toxicidade da salinidade, pois a fertilização exclusiva com esta forma de nitrogênio inibe sua produção, sendo a forma NO3- a mais adequada para o cultivo da espécie.

Plant biostimulants are “green” solutions to improve crop production. Trichoderma spp. and phosphites, ordinarily used as biocontrol agents, can trigger phytostimulation, also promoting endogenous mechanisms involved in plant growth and development. The present study aimed at assessing the efficacy of a phosphite-based formulation (Phosphit-One) and Trichoderma harzianum-T22 on the morpho-physiological response and modulation of the metabolomics profile in zucchini squash plants (Cucurbita pepo L.) cultivated in controlled growth conditions (Fitotron®). The highest values of fresh biomass production (390.9 g plant−1) and root dry weight (5.6 g plant−1) were obtained for Trichoderma-treated plants. This last treatment resulted in an improved physiological performance (SPAD index, CO2 assimilation rate, and Fv/Fm ratio) measured 30 days after transplanting. Both Trichoderma and phosphite treatments induced a broad metabolic reprogramming in leaves, evident also for the phosphite treatment that did not result in a growth promotion. The microbial and the non-microbial treatments showed distinctive signatures in secondary metabolism yet, common responses could be also highlighted. For instance, both Trichoderma and phosphite triggered ROS-mediated signaling processes, together with the accumulation of phenylpropanoids, glucosinolates, and phytoalexins. Furthermore, a significant alteration of phytohormones was observed, with terpenoid gibberellins and brassinosteroids showing the largest differences. The metabolomic signatures induced by Trichoderma and phosphite in zucchini squash provided molecular insights into the processes underlying elicitation of plant defense due to biostimulation. Interestingly, the modulation of plant secondary metabolism by both treatments did not impair plant growth.

The quality and preservability of fresh-cut fruits can be improved by osmotic dehydration (OD). In this study, the impact of Strained Yoghurt Whey (SY Whey) (along with other osmotic solutes) on mass transfer kinetics (water loss, solid gain, water activity decrease), quality attributes (color, texture, sensory characteristics, vitamin C), and microbial stability during OD and subsequent refrigerated storage (5&ndash, 15 &deg, C) of OD-processed pumpkin cuts was studied. The effect of temperature (35&ndash, 55 &deg, C), time (10&ndash, 240 min), and type of osmotic solvent was evaluated to select the optimal processing conditions (55 &deg, C&ndash, 120 min, WL: 9-99-10.86 g w./g i.d.m. SG: 1.47&ndash, 1.79 g s./g i.d.m., aw: 0.89). The use of SY Whey vs. water as solvent enhanced the mass transfer phenomena increasing the solids uptake diffusion coefficient by 20%. Water and whey osmosed samples were of similar quality (32&ndash, 38% increase of hardness, total sensory quality score: 7.9&ndash, 8.2/9.0, vitamin C content: 77&ndash, 81 mg/100 g). At all studied storage temperatures, ODSY Whey samples presented lower quality degradation rates compared to the respective ODWater samples (e.g., almost half for hardness change). The shelf life of both OD processed pumpkin cuts exceeded 90 days at 5&ndash, C (no microbial growth) supporting the applicability of SY whey as novel osmotic solvent.

The reuse of livestock by-products in agricultural management is becoming an increasingly common and necessary practice, both for enabling good plant nutrition and for reducing fertilizer costs. In this way, the objective was to evaluate the biomass production and leaf contents of macronutrients of the Italian zucchini, hybrid Corona, cultivated in two soil types and fertilized with different biofertilizers. The experiment was conducted in pots in Fortaleza, Ceará. The design used was was randomized blocks in subdivided plots. The plots consisted of two soil types (S1: Alfisol Paleudalf soil and S2: Entisol Fluvent) and the subdivided plots of five aerobic fermentation biofertilizers (F1 = quail, F2 = sheep, F3 = bovine + quail + sheep, F4 = bovine and F5 = enriched crab), with five replicates. The analyzed variables were: shoot, root and total dry mass, and macronutrient leaf contents (nitrogen, phosphorus, potassium, calcium and magnesium). The Entisol fertilized with the mixed biofertilizer allowed higher values of shoot and total dry mass of zucchini plants compared to Alfisol and the other biofertilizers, root dry mass was higher when fertilized with mixed biofertilizer in both soils. The Alfisol allowed a greater contribution of leaf macronutrients (N, P, K and Mg) in zucchini plants mainly when associated with mixed and bovine biofertilizers. Leaf contents of Ca were higher when the zucchini was cultivated in Entisol, except when fertilized with sheep biofertilizer. La reutilización de subproductos ganaderos en el manejo agrícola se está convirtiendo en una práctica cada vez más común y necesaria, tanto para permitir una buena nutrición de las plantas como para reducir los costes de fertilización. Así, el objetivo de este estudio fue evaluar la producción de biomasa y el contenido de macronutrientes de las hojas de calabacín italiano, híbrido Corona, cultivado en dos tipos de suelo y fertilizado con diferentes biofertilizantes. El experimento se realizó en macetas, en Fortaleza, Ceará. El diseño utilizado fue en bloques al azar en parcelas subdivididas. Las parcelas consistieron en dos tipos de suelo (S1: Alfisol Paleudalf soil y S2: Entisol Fluvent) y las parcelas subdivididas de cinco biofertilizantes de fermentación aeróbica (F1 = codorniz, F2 = oveja, F3 = bovino + codorniz + oveja, F4 = bovino y F5 = cangrejo enriquecido), con cinco repeticiones. Las variables analizadas fueron: masa seca de la parte aérea, raíz y total, y el contenido foliar de los macronutrientes (nitrógeno, fósforo, potasio, calcio y magnesio). El Entisol fertilizado con el biofertilizante mixto permitió valores más altos de MSPA y MST de las plantas de calabacín en comparación con Alfisol y los otros biofertilizantes, mientras que el MSR fue mayor cuando se fertilizó con el biofertilizante mixto en ambos suelos. El Alfisol hizo posible proporcionar un mayor suministro de macronutrientes foliares (N, P, K y Mg) en las plantas de calabacín principalmente cuando se asocia con biofertilizantes mixtos y bovinos. El contenido de Ca de las hojas fue mayor cuando se cultivó el calabacín en Entisol, excepto cuando se fertilizó con el biofertilizante de oveja. O reaproveitamento de subprodutos da pecuária no manejo da agricultura vem se tornando uma prática cada vez mais comum e necessária, tanto por possibilitar boa nutrição de plantas quanto por reduzir os custos com fertilizantes. Dessa maneira, objetivou-se avaliar a produção de biomassa e os teores foliares de macronutrientes da abobrinha italiana, híbrido Corona, cultivada em dois tipos de solo e adubada com diferentes biofertilizantes. O experimento foi conduzido em vasos, em Fortaleza, Ceará. O delineamento utilizado foi em blocos ao acaso em parcelas subdivididas. As parcelas se constituíram de dois tipos de solo (S1: Argissolo Vermelho Amarelo e S2: Neossolo Flúvico) e as parcelas subdivididas de cinco biofertilizantes de fermentação aeróbia (F1 = codorna, F2 = ovino, F3 = bovino + codorna + ovino, F4 = bovino e F5 = caranquejo enriquecido), com cinco repetições. As variáveis analisadas foram: massa seca da parte aérea, raiz e total, e os teores foliares de macronutrientes (nitrogênio, fósforo, potássio, cálcio e magnésio). O Neossolo fertilizado com o biofertilizante misto possibilitou maiores valores de MSPA e MST de plantas de abobrinha em comparação ao Argissolo e os demais biofertilizantes, já a MSR foi maior quando fertilizada com o biofertilizante misto em ambos os solos. O Argissolo possibilitou maior aporte de macronutrientes foliares (N, P, K e Mg) nas plantas de abobrinha principalmente quando associado aos biofertilizantes misto e bovino. Já os teores de foliares de Ca foram maiores quando se cultivou a abobrinha em Neossolo, exceto quando fertilizada com o biofertilizante ovino.

Plants and animals are sources of various bioactive compounds that exhibit a broad spectrum of health-promoting effects. Scientists continue studies on the chemical composition of many products in search of foods with high nutritional value. The pumpkin (Cucurbita sp.) is unquestionably a source of valuable nutrients. This vegetable is well-known all over the world and it is appreciated due to its high content of carotenoids, but it is still not much used in the processing industry. The aim of present study was to compare the flesh of 15 pumpkin varieties belonging to the Cucurbita pepo and C. moschata species in terms of the bioactive compound content (carotenoids, phenolic acids, flavonols, minerals and vitamins) and to demonstrate whether the variety has an effect on the chemical composition. To date, no such extensive research has been carried out in this area. The research revealed that the pumpkin pulp had high content of carotenoids. In nearly all cases lutein was the most abundant carotenoid. Numerous phenolic acids and flavonols were also identified. All the cultivars contained gallic acid, protocatechuic acid, 4-hydroxybenzoic acid, vanillic acid, chlorogenic acid, caffeic acid, and rutin. The pumpkin pulp also contained alpha- and gamma-tocopherol. No beta- or delta-tocopherol was found. Potassium, calcium, and sodium were the most abundant minerals. The research also proved that the profile of bioactive compounds in the pumpkin pulp was considerably diversified and depended on the species and cultivar

The present study deals with the antimicrobial activity of different extracts of pumpkin (Cucurbita pepo L.) (Seed, Leaves and pulp) against seven microorganisms: two Gram-positive bacteria, i.e. Staphylococcus aureus, Bacillus cereus; three Gram-negative bacteria, i.e. Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis and two yeasts, i.e. Candida albicans & C. parapsilosis. Results revealed that all extracts (Seed, Leaves and pulp) were very effective against P. aeruginosa while some extracts showed no inhibition against S. aureus at all tested concentration (20, 40 & 80 µg/ml). The maximum inhibition zone at 80 µg/ml concentration of n-hexane pulp extract was 39 ± 0.1 mm against P. aeruginosa. The minimum concentration (MIC) for n-hexane pulp extract was 1.65 µg/ml for P. aeruginosa, leading to a conclusion that the n-hexane pulp extract of pumpkin was found to be the most potent. Thus it can be concluded that n- hexane pulp extract of Cucurbita pepo L. was more potent as compared n- hexane seed and leaves extract of Cucurbita pepo L. KEYWORDS: Cucurbita pepo L; n-Hexane extract; Seeds extract; Leaves extract; Pulp extract; Antimicrobial activity.

We investigated the effect of gibberellin and the antigibberellic agent chlormequat-chloride on gas exchange and use of reserve substances in pumpkin seedlings during germination in the light and in the dark. We established that an artificial strengthening or growth inhibition of pumpkin seedlings in conditions of skotomorphogenesis caused an increase in of respiration intensity. Gibberellin treatment increased the proportion of assimilation processes in carbon dioxide gas exchange of seedlings, and growth inhibition by retardant caused an increase in respiratory costs when the nutrition type switches in the light from heterotrophic to autotrophic. The formation by seedlings of the demand for reserve assimilates from cotyledons was largely determined by change of activity of subapical meristems, which is manifested in the acceleration of seed germination, enhancing of histogenesis for the actions of gibberellin and in the weakening of these processes under the influence of retardants. Reserve substances used both oil and nitrogen-containing compounds. The content of protein nitrogen in pumpkin cotyledons decreased more in the light than in the dark, moreover growth inhibition by the retardant slowed down and growth increase by gibberellin accelerated this process both in conditions of photomorphogenesis and skotomorphogenesis.

In order to study the effects of Dekap (0, 1, 2 and 3 L ha-1) foliar applications on some physiological and morphological treats of Cucurbita pepo an experiment was conducted based on Randomized Complete Block Design at Azerbaijan Shahid Madani University Research Farm. The result showed that the foliar application had significant effects on plant length, number of auxiliary branches, leaf number, number of female flower, total number of fruit, fruit diameter, fruit fresh weight, intact fruit number, fruit yield, number of intact and immature seeds in fruits and oil percent. The highest number of auxiliary branches, plant height, leaf number per plant and the highest data for oil percent, seed length, fruit fresh weight and fruit diameter were recorded at 1 and 2 L ha-1 foliar application. The highest data for intact seed number was recorded at 1 L ha-1 foliar application but, the highest number of immature seeds were recorded at 2 and 3 L ha-1 foliar application. The highest data for female flower number and total number of fruits per plant were recorded at 1 L ha-1 treatment. The treatment used in this experiment had not significant effects on protein content, seed dry weight, leaf dry weight, potassium and phosphor concentrations. Considering the fact that, in the present experiment there was no significant difference between 1 and 2 L ha-1 of Dekap foliar applications in some of the evaluated traits, so, we can claim that 1 L ha-1 Dekap foliar application can be recommended for the extension section.

Harvesting and drying are essential procedures to obtain high quality seeds as well as for their conservation during storage. The goal of this research was to identify the physiological maturity stage and to verify the effect of drying speeds on the quality of zucchini seeds. A completely randomized design in a 3x2x2 factor scheme was used, involving three fruit maturation stages (49, 56 and 63 days after anthesis - DAA), two drying speeds (slow and quick) and two storage periods (0 and 6 months). Seed quality was evaluated by germination, first count, accelerated aging, electrical conductivity, tetrazolium, seedling emergence, emergence speed index and seed health test. Moisture content, thousand seed mass and percentage full seeds were also evaluated. Zucchini seeds reach maximum quality at 49 DAA. Slow or quick drying and storage do not affect the physiological quality of seeds that were harvested at 49 DAA. The delayed harvest of fruits reduces the quality of seeds. Quick drying reduces the incidence of the fungi Alternaria, Cladosporium, Phoma and Fusarium, and increases the occurrence of Aspergillus and Penicillium. Resumo: A colheita e secagem são procedimentos essenciais para obtenção de sementes de elevada qualidade, bem como, para sua conservação durante o armazenamento. O objetivo nesta pesquisa foi identificar o estádio de maturidade fisiológica e verificar o efeito de velocidades de secagem sobre a qualidade de sementes de abobrinha. Utilizou-se o delineamento inteiramente casualizado em esquema fatorial 3x2x2, envolvendo três estádios de maturação de frutos (49, 56 e 63 dias após a antese - DAA), duas velocidades de secagem (lenta e rápida) e dois períodos de armazenamento (0 e 6 meses). A qualidade das sementes foi avaliada pelos testes de germinação, primeira contagem, envelhecimento acelerado, condutividade elétrica, tetrazólio, emergência de plântulas, índice de velocidade de emergência e sanidade. Também foi determinado o teor de água, massa de mil sementes e porcentagem de sementes cheias. As sementes de abobrinha atingem máxima qualidade aos 49 DAA. A secagem lenta e rápida e o armazenamento não influenciam a qualidade fisiológica das sementes colhidas aos 49 DAA. O atraso da colheita dos frutos reduz a qualidade das sementes. A secagem rápida reduz a incidência dos fungos Alternaria, Cladosporium, Fusarium e Phoma, e aumenta a ocorrência de Aspergillus e Penicillium.

Background and objectives: Cucurbita Pepo L. is a one-year creeper plant with wide heart shaped leaves covered by tiny trichome with many benefits in its fruit, seed, leaf and root. Currently some studies has been directed to show its preventive and curetive properties for some diseases as an alternative or supplement for other methods. The purpose of present study was to investigate the mentioned properties of Cucurbita Pepo L in Islamic medicine and traditional medicine and to find modern studies on these properties. Methods: The resources used by the researchers in this study have been Tradition references including books and articles Results: Books and articles demonstrated its effectiveness on prevention and treatment of different diseases such as diabetes, anemia, skin diseases, brain diseases and parasitic diseases but there is not an absolute and reliable idea due to dispersal of studies and absence of adequate well controlled randomized clinical trial Conclusion: it seems that further well-designed clinical trials is necessary to discover and confirm the advantages of this miraculous plant.

In this study, physicochemical characteristics, pesticide residues and aflatoxin contaminations of cold pressed pumpkin seed ( Cucurbita pepo L. ) oils cultivated in four different central Anatolia regions of Turkey, were investigated. Lab-scale screw press machine was used to produce cold pressed pumpkin seed oils and the oil contents were found between 42.8%−47.4% for naked seeds. The physicochemical characteristic ( refractive index, viscosity, color value, triglyceride profile analysis, peroxide value, iodine value, free fatty acid, saponification number, unsaponified matter, specific extinction values at 232 and 270 nm ) of cold pressed oils were determined by using different analytical techniques. The results showed that there was a non-significant difference between cold pressed pumpkin seed oils from different regions, in terms of physicochemical characteristics. The contents of pesticide residue and aflatoxin B 1 , B 2 , G 1 and G 2 contamination were determined by using validated UHPLC-MS/MS method. The chlorpyrifos pesticide residue was detected under the limit value declared by official authorities for the quality assessment of edible oils. Aflatoxins weren’t detected in any of studied pumpkin seed oils. Therefore, in food industry the positive effect of screw-pressing application could be useful for preservation of bioactive compounds during edible oil production and also enhancing of their functional properties.

With the aim of determining whether the arbuscular mycorrhizal (AM) inoculation would give an advantage to overcome salinity problems and if the phosphorus (P) concentration can profoundly influence zucchini (Cucurbita pepo L.) plant responses to AM, a greenhouse experiment was carried out with AM (+AM) and non-AM (−AM). Plants were grown in sand culture with two levels of salinity (1 and 35 mM NaCl, giving electrical conductivity values of 1.8 and 5.0 dS m−1) and P (0.3 and 1 mM P) concentrations. The percentages of marketable yield and shoot biomass reduction caused by salinity were significantly lower in the plants grown at 0.3 mM P, compared to those grown at 1 mM P. However, even at high P concentration, the absolute value of yield and shoot biomass of +AM zucchini plants grown under saline conditions was higher than those grown at low P concentration. The +AM plants under saline conditions had higher leaf chlorophyll content and relative water content than −AM. Mycorrhizal zucchini plants grown under saline conditions had a higher concentration of K and lower Na concentration in leaf tissue compared to −AM plants. The P content of zucchini leaf tissue was similar for +AM and −AM treatments at both low and high P concentrations in the saline nutrient solution. The beneficial effects of AM on zucchini plants could be due to an improvement in water and nutritional status (high K and low Na accumulation).

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.

Research was carried out in Latina province (Italy) on rocket, radish and zucchini grown under tunnel. Ten treatments, obtained by the factorial combination of two crop cycles (autumn-winter and winter-spring) and six nitrogen fertilizer forms (organic, organic-mineral, mineral in three modes, control with no nitrogen fer- tilization) were compared. The effects of these treatments were evaluated in terms of yield and nitrate content in the edible organs. In rocket, no significant difference in yield was detected between the autumn-winter and winter-spring crop cycles, although the former cycle resulted in a higher leaf nitrate content. The organic fertilizer treatment and the N-unfertilized control gave the lowest yields, but the mineral fertilizers caused the highest leaf nitrate accumulation. Radish yield did not vary between the two crop cycles, but the hypocotyl nitrate content was higher in the autumn-winter cycle. The crops fertilized with the two highest mineral supplies produced the highest yields, compared with the organic or organic-mineral treatments. In the autumn-winter crop, the mineral N fertilization resulted in the highest hypocotyl nitrate content, whereas in the winter-spring crop only the highest mineral N dose caused a higher nitrate content compared with the organic fertilizer. The highest zucchini yield was obtained from the winter-spring cycle at the two highest mineral fertilizer supplies. In the autumn-winter crop the highest mineral nitrogen dose resulted in the highest fruit nitrate content, while in winter-spring the two highest supplies caused this effect., Advances in Horticultural Science, Vol 25 No 2 (2011)

O objetivo deste trabalho foi quantificar os índices de crescimento, a produção e a distribuição de matéria seca da cultura da abobrinha italiana cultivada em substrato de casca de arroz in natura com solução nutritiva recirculante, em duas épocas de cultivo: primavera-verão de 2005 e verão-outono de 2006, caracterizadas, respectivamente, como períodos de alta e baixa disponibilidades de radiação solar. Cada tratamento correspondeu a uma época de amostragem, sendo a produção de matéria seca quantificada aos 0, 18, 32, 46 e 68 dias após o transplante (DAT) no cultivo de primavera-verão, e aos 0, 15, 29, 43 e 55 DAT no cultivo de verão-outono. A produção de matéria seca foi maior quando a disponibilidade de radiação solar foi mais elevada. Nessa situação (alta disponibilidade de radiação solar), os frutos caracterizaram-se como os maiores drenos da cultura, não ocorrendo o mesmo em condições de baixa disponibilidade de radiação solar. As taxas de crescimento (da cultura, dos frutos, dos órgãos vegetativos aéreos e relativa) também foram mais elevadas quando a radiação solar disponível foi mais elevada. A razão de área foliar e a área foliar específica apresentaram dinâmicas semelhantes à taxa de crescimento relativo, decrescendo com o decorrer do período de cultivo. The objective of this work was to quantify the growth rates, dry matter production and distribution of summer squash grown in raw rice husk medium with recirculating nutrient solution, in two crop seasons: spring-summer 2005 and summer-autumn 2006, which are periods characterized by high and low solar radiation availability, respectively. Each treatment corresponded to a sampling date and dry matter production was evaluated at 18, 32, 46 and 68 days after setting (DAS) in spring-summer, and 15, 29, 43 and 55 DAS in the summer-autumn crop season. Dry matter production was highest in high solar radiation availability conditions. In those conditions, fruits were characterized as the largest drains of the crop, which did not happen in low solar radiation availability. The growth rates (crop, fruits, shoot organs and relative crop rates) also were higher in high solar radiation availability conditions. Leaf area ratio and specific leaf area showed similar dynamics to the relative crop rate, decreasing according with the time-course of the crop.

Organic agricultural production and related food sector has become important in Turkey and over the world. Greenhouse production, especially with soilless culture techniques, might provide growers a viable system to become a consistent supplier of special crops year around for the organic market. Soilless organic systems could recover the disadvantages of soil based greenhouse production and it could create new opportunities for growers in the near future. An experiment was carried out to compare the effects of organic and synthetic- inorganic fertilization on plant growth, nutrient status and yield of soilless grown summer squash. The cultivar 'Alata Yesili F1' was grown in open perlite system during early spring in plastichouse. Two fertilization treatments; (1) control as conventional nutrition by synthetic fertilizers and (2) organic nutrition by plant extract and chicken manure, were used to grow the plants. Growth parameters, namely shoot fresh weight, leaf area, leaf number, root fresh weight and plant height were not different in both treatments for 30 days after transplanting. However, 60 days after transplanting synthetic fertilized plants had 18%, 12%, 25% and 27% higher shoot fresh weight, leaf area, root fresh weight and plant height, respectively. Organic fertilized squash plants had 25% less yield in comparison to synthetic fertilized plants. Number of fruit was less affected from the treatments. However difference in mean fruit weight was 19% and organic fruits were smaller. Therefore the organic fertilized plants had similar number of fruit, but the size of fruits was smaller. Concentrations of N, P, K, Ca, Mg, Fe, Mn, Zn and Cu in plant samples were similar or had some small differences between two nutrition treatments.

Soilless cultivation is a method that permits the achievement of high yields, good control of plant growth and development, and is currently in practice all over the world. Several irrigation systems have been developed for containerized-crops (drip-irrigation and subirrigation). Irrigation system can significantly impact the effect of irrigation water salinity on crop performance. Comparing the subirrigation and drip-irrigation systems using saline and non-saline nutrient solutions can be useful for developing optimal management strategies in semiarid regions which are characterized by the shortage of good quality water. A greenhouse experiment was carried out during the spring-summer season to determine the influence two irrigation systems (drip and subirrigation) and two nutrient solution concentrations (2.0 and 4.1 dS m −1 ) on substrate electrical conductivity (EC e ), growth, yield, fruit quality (dry matter, carbohydrates, protein, Vitamin C), yield water use efficiency (WUE y ) and tissue mineral composition of zucchini squash ( Cucurbita pepo L.). At the mid and at the end of the trial, plants grown with the subirrigation system resulted in a higher EC e in the upper and lower parts of the substrate in comparison to the drip-irrigation system, especially at an EC of 4.1 dS m −1 . At an EC of 2.0 dS m −1 , zucchini yield (total and marketable) was 13% lower with the subirrigation than with the drip-irrigation systems but offered several benefits: higher fruit quality (dry matter, glucose, fructose, starch and total carbohydrates content) and WUE y . The yield reduction with subirrigation was more pronounced at an EC 4.1 dS m −1 , where the zucchini production with subirrigation was lower by 36% than with drip-irrigation. Increasing salinity from 2.0 to 4.1 dS m −1 improved fruit quality (high content of dry matter, reduced sugars, starch, total carbohydrates, and Vitamin C) in both irrigation systems. The results indicate that the choice of the irrigation system appears to be of foremost importance especially when using low quality irrigation water. Unlike subirrigation, using drip-irrigation with saline solution (4.1 dS m −1 ) would be an attractive strategy in limiting yield reduction, taking advantage of the quality effect of saline water and improving the WUE y .

Agrobacterium rhizogenes (wild-type strains 8196 and 15834) transformation of pumpkin (Cucurbita pepo L.) intact seedlings grown in vivo, and 6–8-day-old excised cotyledons cultured in axenic conditions was investigated. Transformed (hairy) roots were successfully induced only on the excised cotyledons with the strain 8196, while intact seedlings failed to form hairy roots with either of the two different bacterial strains. Axenic hairy-root cultures established on MS medium without hormones grew vigorously. Mannopine was detected in all transgenic root clones examined. The peroxidase activity in transformed roots was higher compared with normal roots. Electrophoretic analyses of soluble proteins and isoperoxidases showed substantial differences between transformed and normal pumpkin roots.