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World agriculture is facing a great challenge since it is necessary to find a sustainable way to increase food production. Current trends in advancing the agriculture sector are based on leveraging remote sensing technology and the use of biostimulants. However, the efficient implementation of both of these on a commercial scale for the purposes of productivity improvement remains a challenge. Thus, by proposing a crop monitoring strategy based on remote sensing data, this paper aims to verify and anticipate the impact of applying a Glycinebetaine biostimulant (GB) on the final yield. The study was carried out in a rice-producing area in Eastern Spain (Valencia) in 2021. GB was applied by drone 33 days after sowing (tillering phase). Phenology was monitored and crop production parameters were determined. Regarding satellite data, Sentinel-2 cloud-free images were obtained from sowing to harvest, using the bands at 10 m. Planet data were used to evaluate the results from Sentinel-2. The results show that GB applied 33 days after sowing improves both crop productive parameters and commercial yield (13.06% increase). The design of the proposed monitoring strategy was based on the dynamics and correlations between the visible (green and red) and NIR bands. The analysis showed differences when comparing the GB and control areas, and permitted the determination of the moment in which the effect of GB on yield (tillering and maturity) may be greater. In addition, an index was constructed to verify the crop monitoring strategy, its mathematical expression being: NCMI = (NIR − (red + green))/(NIR + red + green). Compared with the other VIs (NDVI, GNDVI and EVI2), the NCMI presents a greater sensitivity to changes in the green, red and NIR bands, a lower saturation phenomenon than NDVI and a better monitoring of rice phenology and management than GNDVI and EVI2. These results were evaluated with Planet images, obtaining similar results. In conclusion, in this study, we confirm the improvement in rice crop productivity by improving sustainable plant nutrition with the use of biostimulants and by increasing the components that define crop yield (productive tillers, spikelets and grains). Additionally, crop monitoring using remote sensing technology permits the anticipation and understanding of the productive behavior and the evolution of the phenological stages of the crop, in accordance with crop management.

Chufa, also known as tigernut, is a typical irrigated crop in Valencia, Spain, where it is traditionally cultivated for its tubers. Its cultivation uses large amounts of water, in the order of 10,000 m3 ha(‑1) year‑1. During the last years, the research team in which this study has been developed, has carried out several studies leading to improve the irrigation water use efficiency in chufa. Although these improvements are considerable, they are not definitive, as the water requirements of the crop are still unknown. To know these needs, it would be recommended to determine the crop evapotranspiration (ETc). The experiment was carried out on an experimental plot of the Universitat Politecnica de Valencia, included in the traditional cultivation area. This plot includes a lysimetric station (Smart Field Lysimeter) which allows determining the daily ETc. In addition, the plot is equipped with a meteorological station, which provides the necessary parameters for the determination of the daily reference crop evapotranspiration (ETo) through the FAO-56 Penman-Monteith method. Relating the values of ETc and ETo, the crop coefficient (Kc) values corresponding to the different growth stages, has been estimated from the data obtained during the crop cycle. Considering the crop development, the length of the four growth stages were considered as 21, 76, 43 and 29 days for initial, development, mid-season and late season stages, respectively. The single Kc values for the initial, mean and end of the late season stages were established as 0.25, 1.43 and 0.75, respectively. The use of these Kc values will allow adjusting irrigation water doses to water requirements, thus reducing the volume of water applied and improving the irrigation application efficiencies in chufa crop.

Fertilizer-use efficiency is one of the most critical concerns in rice cultivation to reduce N losses, increase yields, and improve crop management. The effects of a new polymeric-coated controlled-release fertilizer (CRF) were compared to those of other slow-release and traditional fertilizers in a microscale experiment, which was carried out in cuvettes under partly controlled ambient conditions, and a large-scale field experiment. To evaluate the fertilizer’s efficiency, nitrogen and water-use efficiency were calculated using the measurement of different photosynthetic and crop yield parameters. Improved responses regarding some of the analyzed physiological and growth parameters were observed for those plants fertilized with the new CRF. In the microscale experiment, significantly increased yields (ca. 35%) were produced in the plants treated with CRF as compared to traditional fertilizer. These results were in accordance with ca. 24% significant increased levels of N in leaves of CRF-treated plants, besides increased P, Fe, Mn, and cytokinin contents. At the field scale, similar yields were obtained with the slow-release or traditional fertilizers and CRF at a 20% reduced N dose. The new controlled-release fertilizer is a urea-based fertilizer coated with lignosulfonates, which is cheaply produced from the waste of pulp and wood industries, containing humic acids as biostimulants. In conclusion, CRF is recommended to facilitate rice crop management and to reduce contamination, as it can be formulated with lower N doses and because it is ecological manufacturing., This research was funded by the Spanish Ministry of Economy and Competitiveness, grant number RTC-2014-1457-5, with the project entitled “Los CRFs como alternativa a los fertilizantes tradicionales: buscando una mayor protección del medio ambiente” (“CRFs as alternative to traditional fertilizers: looking for a better protection of the environment”).

[EN] Chufa is a typical crop in Valencia, Spain, where it is cultivated in ridges with furrow irrigation. It uses large volumes of water, and thus, different studies have been undertaken to maximize irrigation water use efficiency to obtain important water savings. Particularly, different values for turning water on, considering the basis of volumetric soil water content were analysed in drip irrigation. It was reported that starting each irrigation event when the volumetric soil water content dropped to 90% of the field capacity resulted in the best yield, and the best irrigation water use efficiency was obtained when it dropped to 80% of the field capacity. However, these results may be improved by defining the optimum criteria for turning water off, which is the aim of the present research. This investigation, conducted in 2015, 2016 and 2017, analises the productive response of the drip irrigated chufa crop, determining the yield and the irrigation water use efficiency. The volumetric soil water content was monitored using multi-depth capacitance probes, with sensors at 0.10, 0.20 and 0.30 m below the top of the ridge. Each irrigation event started when the volumetric soil water content at 0.10 m dropped to 85% of field capacity. Three irrigation strategies were considered. T1: each event resulting in water being turned off when the sum of the volumetric soil water content values that were measured at 0.10, 0.20 and 0.30 m reached the corresponding field capacity value; T2: turning water off in each event when the volumetric soil water content values that were measured at 0.20 m reached the corresponding field capacity value; and T3: each irrigation event applying 8.5 mm in 2015 and 2016, as well as 9.8 mm in 2017. Overall, the T2 strategy resulted in the largest yield, and T3 resulted in the highest irrigation water use efficiency in 2015 and 2016. The average tuber weight and dry matter content did not differ between the irrigation strategies., This work was supported by the Generalitat Valenciana [GV/2017/037].

[EN] Salinity and water shortages are two of the biggest environmental constraints that crops have to face in the climate change scenario. A fast and efficient way to overcome these stresses under the prism of a sustainable crop management is the use of grafting, combining the desired cultivar with the rootstock providing tolerances to abiotic stresses. Our aim was to validate three accessions previously selected for their tolerances to salt and water stresses (A25, B14 and C12) as rootstocks, in real field conditions. The physiological and productive behavior of the commercial pepper 'Adige' (A) grafted onto these accessions was compared along the growing cycle with this cultivar grafted onto the commercial rootstock 'Antinema' (ANT) and with the ungrafted pepper plant (A). Under water and salt stress, grafted plants onto the selected accessions, gave higher marketable yields than ungrafted plants or that plants grafted onto ANT, particularly the A25 accession. This rootstock was able to maintain high photosynthesis levels under stressing conditions through different adjustments made in the physiological processes, such as proline accumulation. The ANT rootstock showed comparable yields to A25 in control conditions. Under salt stress, Na+ and Cl- were equally accumulated in A/A25 plants and the ungrafted ones, but A/ANT, A/B14 and A/C12 were more restrictive in their absorption along the growing season. These results reinforce the idea that the use of tolerant pepper rootstocks is a good adaptation strategy for abiotic stressing conditions. The results also suggest that the abiotic stress was alleviated by the lack of negative effects mainly on photosynthesis, which maintained plant growth and the marketable yield., This work has been financed by INIA (Spain) through Project RTA2013-00022-C01 and the European Regional Development Fund (ERDF).

[EN] With the objective of studying the effect of two nutrient solutions and two crop systems (greenhouse and openfield) on nitrate accumulation, incidence of tipburn and chlorophyll content, endive (cv. Cuartana) was planted in 8 L pots, filled with a mixture of coconut coir:perlite (1:1) in three different cycles C1 (winter), C2 (spring) and C3 (summer). Plants were irrigated with two nutrient solutions of different nitrate content: S1, low ([NO¿3] = 7.91 mmol L¿1) and S2 moderate nitrate content ([NO¿3] = 16.91 mmol L¿1). Nitrate content was determined by reflectometry, tipburn was evaluated using a qualitative scale and chlorophyll content by soil plant analysis development(SPAD) values. Plants irrigated with S2 showed higher nitrate accumulation in leaves in all cycles, however, no influence of the nutrient solution was observed on the incidence of tipburn. Greenhouse-cultivated plants accumulated more nitrates than those cultivated in open field and also showed a higher incidence of tipburn and SPAD values.

[EN] New sources of water stress and salinity tolerances are needed for crops grown in marginal lands. Pepper is considered one of the most important crops in the world. Many varieties belong to the genus Capsicum spp., and display wide variability in tolerance/sensitivity terms in response to drought and salinity stress. The objective was to screen seven salt/drought-tolerant pepper accessions to breed new cultivars that could overcome abiotic stresses, or be used as new crops in land with water and salinity stress. Fast and effective physiological traits were measured to achieve the objective. The present study showed wide variability of the seven pepper accessions in response to both stresses. Photosynthesis, stomatal conductance and transpiration reduced mainly under salinity due to stomatal and non-stomatal (Na+ accumulation) constraints and, to a lesser extent, in the accessions grown under water stress. A positive relationship between CO2 fixation and fresh weight generation was observed for both stresses. Decreases in Ys and YW and increased proline were observed only when accessions were grown under salinity. However, these factors were not enough to alleviate salt effects and an inverse relation was noted between plant salt tolerance and proline accumulation. Under water stress, A31 was the least affected and A34 showed the best tolerance to salinity in terms of photosynthesis and biomass., INIA, Spain (Project RTA2013-00022-C02-01 and doctoral fellowship FPI-INIA to LLS); European Regional Development Fund (ERDF)

[EN] The artichoke crop in Spain is mainly reproduced by vegetative propagation, using cuttings, stumps or stalks, the cultivar ‘Blanca de Tudela’ with green heads being the most important. In the south of Valencia and Murcia Communities the cultivar ‘Violet de Provence’ with purple heads is also produced, to be exported to France. The vegetative propagation presents physiological, pathological and financial drawbacks. For that reason this work analyzes the viability of new seed cultivars of artichoke. The agronomic behaviour of 20 seed propagated cultivars/ lines was studied, eleven of them with green heads and nine with purple heads, and using ‘Blanca de Tudela’ and ‘Violet de Provence’ as respective controls, being both asexually propagated cultivars. Seeds were sown on 8 June 2010 and transplanting was carried out on 21 July 2010, in open-field conditions in Paiporta (Valencia, Spain). The highest early yield in green head cultivars/lines was achieved by NUN 4011 (0.51 kg m-2) not differing from that obtained in ‘Blanca de Tudela’ (0.4 kg m-2). The highest early yields in purple head cultivars/lines was obtained by NUN 4146 (0.44 kg m-2), not showing differences either from the control ‘Violet de Provence’ (0.4 kg m-2). At end of harvest, the greatest cumulative yield in the green head cultivars/lines was reached by ‘NUN 4011’ (2.75 kg m-2); while among purple head cultivars/lines it was achieved by ‘Opal’ (2.24 kg m-2). Final yield in both green and purple head control cultivars was lower than those for the most productive seed propagated cultivars/lines. Both ‘NUN 4011’ and ‘Opal’ excelled by their low level of non-marketable yield and good quality of artichoke heads., Thanks to Conselleria de Agricultura Pesca y Alimentación de la Comunidad Valenciana for the financial assistance in this study, which is included in the developed research for Programa Hortofrutícoloa, an I+D+i project.

[EN] A two-year study was conducted to analyze the yield and irrigation water-use efficiency of chufa crop in response to planting configuration and drip irrigation scheduling as a function of the volumetric soil water content. The planting configurations were: beds with three plant rows and three driplines (B3), beds with three plant rows and two driplines (B2), beds with two plant rows and two driplines (b), and ridges (R). The yield was affected by the planting configuration; greater yields were obtained in beds (on average 2.36 kg m−2) than in R (2.14 kg m−2). Considerably less irrigation water was applied in R and in B2 than in beds B3 and b. The irrigation water-use efficiency was affected by the planting configuration in the same line that the irrigation water was applied, with greater values being obtained in B2 (7.58 kg m−3) than in the R (6.63 kg m−3), which in turn was higher than B3 (5.92 kg m−3) and b (5.69 kg m−3). These values of the irrigation water-use efficiency were considerably higher than those obtained in previous experiments (based on the volumetric soil water content in the ridges). Neither the yield nor the average tuber weight were affected by the position of the different planting rows in the bed., This study was funded by the Regulatory Council of Denomination of Origin Chufa of Valencia of Spain.

[EN] The Spanish type cultivar 'Piel de Sapo' (Cucumis melo L var. saccharinus), has a limited compatibility with the Cucurbita maxima x Cucurbita moschata hybrids currently used as rootstocks. Double grafting can be used to improve compatibility between rootstock and scion by means of an intermediate rootstock compatible with both. Non-grafted, single, and double grafted melon plants of the cultivar Piel de Sapo were evaluated for water, nutrient absorption, photosynthesis activity, biomass production in early phases, as well as for yields and fruit quality in a long term trial. The hybrid 'Shintoza' (C. maxima x C. moschata) was used as rootstock, and the cantaloupe type melon cultivar 'Sienne' as an intermediate scion. Grafting did not affect net photosynthetic values, yet increased water use efficiency (35%). Double grafted plants increased aerial dry weights (66% and 31% with respect to non-grafted and simple graft plants, respectively), and also increased capacity for uptaking beneficial minerals (between 61% and 13% and particularly for NO(3)(-), P, K, Ca, Mn, and Zn) with respect to non-grafted and single grafted plants. The quantum efficiency PSII photochemistry values increased in double grafted plants (12%) with respect to the control plants. Consequently, double grafting on a vigorous rootstock such as 'Shintoza', with an intermediate scion, results in improved mineral and water absorption and achieves an increase in ion influx to the scion - so enabling an increase in light photosynthetic reaction and biomass. Double grafted plants increased fruit yield when compared to simple grafted and non-grafted plants (12% and 56%, respectively) and did not affect fruit quality in terms of degrees Brix and colour. In conclusion, double grafting presents several beneficial aspects that are counter-balanced by the extra cost of the technique. The difference in yields reflects compatibility problems., The authors gratefully acknowledge Conselleria de Agricultura, Pesca y Alimentacion (Generalitat Valenciana, Spain) for its financial support especially for the contract for A. Calatayud. The revision of this paper was funded by the Universidad Politecnica de Valencia, Spain.

The grafting technique is broadly used in Spain to control some soil pathogens in watermelon crop. However, it is scarcely used in melon crops, especially in `Piel de Sapo¿ cultivars, since them have low affinity with Cucurbita hibrida, the most important rootstock used in these crops, having the most resistance to the main soil borne diseases, specially Monosporascus and Melon Necrotic Spot Virus (MNSV). Some melon cultivars of `Cantaloup¿ and `Galia¿ types have proved to be tolerant to some diseases and have good affinity with `Piel de Sapo¿ cultivars but they do not resist intense attacks of Monosporascus. In the present study we tested the double grafting of four `Piel de Sapo¿ cultivars (`Ricura¿, `Torpedo¿, `Piel de Sapo IS¿ and `Sancho¿) on Cucurbita hibrida (`Strongtosa¿) using as intermediate rootstock four melon cultivars: three french `cantaloupe¿ varieties (`Troubadour¿, `Charentais¿ and `Sienne¿) and `Galia¿; using as controls the single grafted and the non-grafted plants. The grafting, both double and single, increased yields and fruit weights compared to non-grafted plants. The double grafted plants, whatever the intermediate rootstock used, did not increase yields or fruit weights compared to single grafted plants in all scion cultivars.

Plants of ‘Imperial Star’ and ‘Prelude’, planted on 30th July 2002, were sprayed three times, every two weeks, with gibberellic acid (GA3), chlormequat (CCC) and paclobutrazol (PBZ) at 30, 795 and 300 mg L-1respectively, starting on 13th September, applying a total of 375 L ha-1. Untreated plants served as controls. At the end of December 2002, plants of ‘Imperial Star’ had produced with all treatments, particularly with GA3, but ‘Prelude’ plants had only produced when treated with GA3. By the end of February 2003, plants of both cultivars treated with GA3 yielded the same, similar to ‘Imperial Star’ plants treated with CCC. With the exception of GA3-treated plants, ‘Imperial Star’ produced significantly higher yields than ‘Prelude’. By the end of the experiment (end of May 2003) ‘Imperial Star’ plants also yielded more than ‘Prelude’ while GA3-treated plants of ‘Imperial Star’ produced significantly less than those of other treatments included controls. With all treatments, ‘Prelude’ gave similar yields. Average head weight was slightly higher in ‘Imperial Star’ than in ‘Prelude’, and it was similar among treatments except in plants treated with GA3. In this case, the GA3-treated plants yielded a lower head weight at the end of February and May 2003. Unmarketable production was higher in the cultivar ‘Imperial Star’ and slightly higher, albeit not significantly, in GA3-treated plants.

Cape gooseberry (Physalis peruviana L.) is a solanaceous plant. The growth and time-course of nutrient accumulation of the plant and its partitioning between roots, stems, leaves, and fruits were examined. The study was conducted analyzing two nutrient solutions in soilless culture under greenhouse conditions during two consecutive seasons. The macronutrient contents were analyzed. On average, the yield was 8.9 t.ha(-1). Growth of the plant until 90 d after transplanting obeys an exponential function of time and the relative growth rate for this period was determined. Nitrogen (N) was the element that showed the highest concentration, corresponding to leaves (4.67%), followed by potassium (K) in stems (4.46%). The highest accumulations of N, phosphorous (P), calcium (Ca), and magnesium (Mg) were found in leaves and of K in the stems. Potassium showed the highest nutrient accumulation (29 g.plant(-1)) and the highest specific uptake rate.

[EN] Grafting has been proposed as an interesting strategy that improves the responses of crops under salinity. In pepper, we reported increased fruit yield of the commercial 'Adige' cultivar under salinity when grafted onto accessions Capsicum chinense Jacq. 'ECU-973' (12) and Capsicum baccatum L. var. pendulum 'BOL-58' (14), whereas no,effect was observed when grafted onto accession Capsicum annuum L var. 'Serrano' (5). We also analysed the physiological and biochemical mechanisms related to the tolerance conferred by these rootstocks. Responses to salinity (40 mM NaCl) were studied in the different plant combinations for 30 days by determining water relations, mineral content, proline accumulation, photosynthetic parameters, nitrate reductase activity and antioxidant capacity. Higher salt tolerance was achieved when the 'Adige' cultivar was grafted onto the 12 genotype, which allowed not only lower Na+ and Cl- accumulation in the scion, but also ion selectivity maintenance, particularly Na+/K+ discrimination. These traits led to a minor negative impact on photosynthesis, nitrate reductase activity and lipid peroxidation in grafted scion leaves. This work suggests that using tolerant pepper rootstocks that maintain the scion's ion homeostasis is a promising strategy to provide salinity tolerance and can consequently improve crop yield., This work has been financed by INIA (Spain) through Project RTA2010-00038-C03-01 and the European Regional Development Fund (ERDF). C.P. is beneficiary of a doctoral fellowship (FPI-INIA) associate with this project.

Sweet pepper is one of the most important vegetable crops in arid and semiarid regions. Grafting has been proposed as an interesting strategy that improves the responses of crops under the salinity and hydric deficits occurring in these areas. In a previous work, we selected Capsicum spp accessions with different degrees of salinity and hydric stress tolerance to be used as rootstocks (the highest to lowest): Capsicum chinense Jacq. ‘ECU-973’ (code 12), Capsicum baccatum L. var. pendulum ‘BOL-58’ (code 14) and Capsicum annuum L var. ‘Serrano’ (code 5). The behavior of commercial cultivar seedlings grafted onto these rootstocks was compared during 14 days under water stress (5% polyethylene glycol) and salinity (40 mM NaCl) in hydroponic culture. Different physiological parameters were measured to test the hypothesis that tolerance might be related to the role of rootstock in altering the stress perception by the scion and to identify differences in pepper-grafted plants adaptation mechanisms in response to salt and osmotic stresses. At a similar osmotic pressure of the solution, grafted plants onto the 12 and 14 rootstocks activated tolerance mechanisms based on ion specific responses under salinity, whereas osmotic adjustment based on proline accumulation was performed under water stress. The maintenance of the scion's homeostasis under salinity was achieved through the restriction of Cl- transport to leaves and to diminished Na+ loading in roots and leaves, thus favouring K+ uptake. Under both stresses, a minor negative impact on photosynthesis, nitrate reductase activity and lipid peroxidation in scion leaves grafted onto 12 and 14 rootstocks was observed. In conclusion, the results of these works reinforce that the use of tolerant pepper rootstocks is a promising strategy to provide salinity and water stress tolerance and can consequently improve crop yield.

Cultivated nutsedge is a common crop in Valencia (Spain). The aim of this research, which was conducted over two consecutive years, was to compare the productive response of the nutsedge crop with drip irrigation and traditional furrow irrigation, calculating the yield and the irrigation water use efficiency (IWUE). The volumetric soil water content was monitored with capacitance probes. Four irrigation strategies were considered: three in drip irrigation [D70, D80 and D90 with refill points at 70, 80 and 90 % of the field capacity, respectively] and one in furrow irrigation (refill point at 60 % field capacity); in the second year, the irrigation management was automated. On average, strategy D90 produced the highest yield and D70 the lowest, while the highest IWUE was obtained with D80 and the lowest with furrow irrigation. Considering the automation of irrigation management, strategy D90 led to the highest yield and to the highest IWUE., This study was funded by the Regulatory Council of Denomination of Origin Chufa of Valencia of Spain.

The production of watermelon in soilless culture is increasing in importance as a complement of the grafting technique to control phytopathological problems. The influence of this crop production system in fruit quality, particularly in sugar accumulation patterns, have not been studied yet comparing different substrates and the production in soil. On the other hand, the use of the synthetic cytokinin CPPU as an alternative or complementary method to fruit setting in watermelon production is also increasing in importance and its influence on fruit quality are not well clarified. In the present experiment two setting procedures (CPPU sprayed to the pistilate flowers and hand pollination with male flowers of the diploid cultivar ‘Dulce Maravilla’) were compared in three growing media (perlite, coir dust and rockwool) in watermelon plants of the triploid cultivar ‘Reina de Corazones’ grafted onto ‘Shintoza’. Plants were grown in a greenhouse from April to July. Yields, fruit weight, Hunter colour parameters and soluble sugars accumulation were determined by sampling fruits at 20, 25, 30, 35, 40 and 45 days after fruit setting. The substrate or fruit setting procedure did not influence yields. Fruit weight was significantly higher in plants grown in rockwool than in the other substrates and was not affected either by the fruit setting procedure. No interactions between both factors under study were found in any of the quality parameters analyzed. Sugar accumulation patterns and contents were similar to those found in other studies. CPPU delayed the internal redness colour and sugar accumulation, particularly of sucrose, but was dependent on substrates. The internal redness colour was faster in fruits grown in perlite. Little influence of the substrate was found in the fructose or glucose accumulation patterns but sucrose and total soluble solids were higher in fruits from plants cultivated in perlite. Since sugar accumulation in watermelon is affected by water availability, these results seem to be related to differences in the available water holding capacity of the substrates.

[EN] The localized application of the synthetic cytokinin CPPU ((2-chloro-4-pyridyl)-N-phenyl urea) to ovaries at flower opening was as effective as free pollination in setting parthenocarpic fruit in the triploid watermelon cultivar ' Reina de Corazones', and increased yield per unit land area by at least 50%, simply due to the lack of requirement for diploid pollen producing plants within the orchard. The application of the synthetic auxin 2,4-D (2,4-dichlorophenoxy acetic acid) as a full coverage spray, was also effective in setting fruit; total yield was however 10% smaller than in the CPPU-treated plots, but the cost of application was much less expensive. These applications had no adverse effect on fruit quality, and their effectiveness in commercial watermelon production was evaluated over 4 years. Localized applications of 2,4-D to ovaries were less effective in setting fruit, and increased hollow fruit.

The most significant problem in local accessions of serpent melon in Spain is their extreme susceptibility to Fusarium, particularly when grown at high temperatures. Comparing the effectiveness of two rootstocks (the cucurbit hybrid, Shintoza, and the melon cultivar ‘Accent’, resistant to Fusarium) in two cycles (spring and autumn), this study examines the behaviour of the serpent melon cultivar ‘Alficoz SGM’ cultivated in a glasshouse and grown in coconut peat substrate. In the spring cycle, the serpent melon was sown on 10 December 1999 and rootstocks on 20 December 1999. Planting took place on 10 February 2000. In the autumn cycle, the serpent melon and rootstocks were sown on 19 July 2000 and 25 July 2000 respectively, and planting was done on 18 August 2000. In the spring cycle, the harvest was staggered between 31 March and 10 July 2000. Yields varied between 11.1 and 28.7 kg plant-1, a significantly higher yield being recorded in grafted plants. Grafting also reduced mortality caused by Fusarium as well as increased fruit weight. In the autumn cycle, the harvest was staggered between 22 September and 25 October 2000. Yields were very low (between 0.7 and 3 kg plant-1) as a consequence of a severe viral affection. Grafting not only significantly increased yields compared with controls, but it also improved fruit weight and reduced mortality caused by Fusarium.

[EN] Water stress is a major environmental factor that limits crop production and it is important to develop crop varieties with higher yield under water scarcity. Increased pepper tolerance to water stress through grafting onto robust rootstocks could be an optimal alternative in the context of environmentally friendly agriculture. Our work evaluated the behaviour of 18 pepper genotypes during vegetative and reproductive stages under water stress in order to select tolerant genotypes to be used as rootstocks for pepper cultivation. The pepper tolerance screening was based on photosynthetic parameters. The genotypes Atlante, C-40, Serrano, PI-152225, ECU-973, BOL-58 and NuMex Conquistador were revealed as the most tolerant genotypes to water stress because they maintained net photosynthetic rate levels under water stress conditions. The selected genotypes were validated as rootstocks on a pepper cultivar in terms of productivity under severe water stress. Plants grafted onto cvs Atlante, PI-152225 and ECU-973 showed higher marketable yields when compared with ungrafted cultivar., Supported by Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Project RTA2010-00038-C03-01-03 and the European Regional Development Fund.

Chufa, also known as tigernut, is a typical crop in Valencia, Spain, where it is cultivated in ridges with furrow irrigation. This paper examines the effects of the planting strategy (PS) and irrigation system (IS) on yield and irrigation water use efficiency (IWUE) on the basis of the results from a two-year study. The authors analyzed three PS, ridges with a plant row (R) and flat raised beds containing two (B2) or three (B3) plant rows and compared two IS, furrow (FI) and drip irrigation (DI). Irrigation was based on the volumetric soil water content (VSWC), continuously monitored with capacitance sensors. Each irrigation event started when the VSWC in R dropped to 60 or 80% of the field capacity in FI or DI, respectively. Beds and ridges were irrigated simultaneously and for the same duration. There were differences among IS and PS, with DI and B2 obtaining the highest yield. On average, DI produced higher IWUE values than FI; the highest IWUE was obtained in R for DI, and the lowest IWUE was obtained in R for FI. Thus, modifications to the PS and the IS in chufa cultivation will increase IWUE and lead to major water savings.

Three chufa cultivars, were selected and characterized, based on quantitative traits that showed high heritability: leafy shoots per plant; length, length/width rate and unit weigth of tuber; tubers per plant; inflorescences per unit surface. GA is characterized for its large size and unit weight of their tubers, the low number of leafy shoots, the low number of tubers per plant and the intense bloom. The large tuber is very appreciated as a fresh product. AB produces small spherical tubers with high fat content, appreciated in the production of horchata, has a good tuber yield. LA produces average size oval tubers with high fat content. It yields more and is appreciate in the production of horchata. RAPD technique can be used for the characterization of chufa cultivars; it would improve the correct identification of cultivars in order to protect patent rights.

This two-year study (1994–95) analyses the effects of different irrigation treatments (using a drip irrigation system and furrow irrigation) and the subsequent varying degrees of soil water tension on both the productive response of tomato and the appearance of fruit cracking. Three cultivars were tested in these experiments: Evita 52®, a cherry tomato, Aguilas®, a fresh-market tomato and Guay®, a processing tomato. The fresh-market cultivar and that of the cherry type were grown in greenhouses using a drip irrigation system. The processing cultivar was grown under a floating cover with furrow irrigation. The irrigation treatments for both years were based on crop evapotranspiration (ETc) and their values were 0.5, 1.0 and 1.5 ETc for the first year, and 0.4, 0.8 and 1.2 ETc for the second year for the cultivars tested in greenhouses with the drip irrigation system. The cultivar grown outdoors received furrow irrigation with the values 0.5 and 1.0 ETc for the first year and 0.4 and 0.8 ETc for the second year. Soil water was measured with tensiometers during the entire treatment period. Higher rates of irrigation increased yields in two of the three cultivars. Longitudinal cracking was the type most frequently observed in these experiments. In both years of the furrow irrigation experiments, the incidence of cracking was high when large fluctuations of the soil matric potential were induced after having maintained high negative values of this parameter during several previous days. In the experiments using drip irrigation, cracking was limited, but increased when high fluctuations in the soil matric potential were induced after having maintained high negative values of matric potential for several previous days, as was the case with furrow irrigation. Differences in cultivar susceptibility to fruit cracking were detected in the experiments. More cracking occurred during periods of higher temperatures.

The effects of different irrigation treatments under furrow irrigation, and their respective soil water tension regimes on both the productive response and presence of fruit cracking were studied in this experiment, which was carried out in 1993–94. Two tomato cultivars used for processing, Guay® and Rio Grande@reg, were grown under floating cover with furrow irrigation. Irrigation treatments were based on ETc, and were 0.5 and 1 ETc. Soil water tension was measured with tensiometers throughout the treatment. Higher levels of irrigation increased yields. Longitudinal cracking appeared most frequently in this experiment. Fruit cracking was considerable after high fluctuations in soil matric potential following high negative values of this parameter. Differences in fruit cracking were detected between irrigations. Differences in cultivar susceptibility to fruit cracking were also detected. Fruit cracking was more frequent when temperatures were higher.

Waiting bed plants, used succesfully in Holland and Belgium, reduces the time between planting and harvest and could facilitate the production of strawberries during the winter in the warm climate of the Spanish mediterranean coast. Experiments were designed to investigate the behaviour of different types of multicrown plants of the cultivars Chandler, Pajaro and Vilanova, cold stored plants (CS), fresh plants from high elevation (HE) and fresh plants from low elevation (LE). These were planted in soil under a large polyethylene tunnel. Planting took place at the end of summer for CS plants and at the beginning of the winter for LE and HE plants. Harvesting from CS plants started at the end of November, continued during the winter and spring, with a cumulative total of more than 700 g/plant at the end of May. HE and LE plants started production at the beginning of March with both giving significantly lower production than CS plants, with no differences between them. Average fruit weight was significantly higher in HE than in LE plants.

[EN] Recent studies have shown that tolerance to abiotic stress, including water stress, is improved by grafting. In a previous work, we took advantage of the natural variability of Capsicum spp. and selected accessions tolerant and sensitive to water stress as rootstocks. The behavior of commercial cultivar 'Verset' seedlings grafted onto the selected rootstocks at two levels of water stress provoked by adding 3.5 and 7% PEG (polyethylene glycol) was examined over 14 days. The objective was to identify the physiological traits responsible for the tolerance provided by the rootstock in order to determine if the tolerance is based on the maintenance of the water relations under water stress or through the activation of protective mechanisms. To achieve this goal, various physiological parameters were measured, including: water relations; proline accumulation; gas exchange; chlorophyll fluorescence; nitrate reductase activity; and antioxidant capacity. Our results indicate that the effect of water stress on the measured parameters depends on the duration and intensity of the stress level, as well as the rootstock used. Under control conditions (0% PEG) all plant combinations showed similar values for all measured parameters. In general terms, PEG provoked a strong decrease in the gas exchange parameters in the cultivar grafted onto the sensitive accessions, as also observed in the ungrafted plants. This effect was related to lower relative water content in the plants, provoked by an inefficient osmotic adjustment that was dependent on reduced proline accumulation. At the end of the experiment, chronic photoinhibition was observed in these plants. However, the plants grafted onto the tolerant rootstocks, despite the reduction in photosynthetic rate, maintained the protective capacity of the photosynthetic machinery mediated by osmotic adjustment (based on higher proline content). In addition, water stress limited uptake and further NO3- transfer to the leaves. Increased nitrate reductase activity in the roots was observed, mainly in plants grafted onto the sensitive rootstocks, as well as the ungrafted plants, and this was associated with the lessened flux to the leaves. This study suggests that PEG-induced water stress can be partially alleviated by using tolerant accessions as rootstocks. (C) 2014 Elsevier GmbH. All rights reserved, This work was financed by INIA (Spain) through project RTA2010-00038-C01 and the European Regional Development Fund (ERDF).

A factorial experiment, was carried out in a greenhouse with pepper cv. Italverde (Italian type) in soilless culture using coir media that had been already been used for two years. Three media were tested based on ratios of coir dust and coir chips in the following proportions (% by volume respectively); 100:0, 60:40 and 40:60. These were compared under three irrigation schedules: high frequency (HF), medium frequency (MF) and low frequency (LF) derived respectively from a depletion ratio of 5%, 10% and 20 % of saturated substrate, in order to regulate nutrient solution use more efficiently. The results showed that significantly higher commercial yields (early and total yield) were obtained with the 100% coir dust and 60:40 coir dust: coir chip growing media. The greatest commercial yield was achieved with HF and MF frequency irrigation but the advantage was not statistically significant. Malformed fruit was the most important disorder reducing marketable yield, mainly in the 100% coir dust and 60:40 coir dust: coir chip growing media. Blossom-end-rot and sunscald only appeared at the end of this experiment; the highest BER incidence was in the 60:40 coir dust: coir chip substrate. Some statistically interactions between factors were also found. The greatest average marketable weight was obtained by low and medium frequency irrigation. The highest value of irrigation efficiency for marketable production was obtained by low frequency irrigation combined with the 60:40 coir dust: coir chip medium.

[EN] The production of seed propagated artichoke is considered one possible alternative to the vegetative propagation of green and purple artichoke heads. One drawback of using seed propagated artichokes is their late entry into production. In this study different gibberellic acid (GA3) concentrations, sprayed over different cultivars of seed propagated artichoke, are analysed in order to know the influence on earliness, yield, quality and crop behaviour. The experiment was carried out at the Experimental Station of Foundation Ruralcaja in Paiporta (Valencia, Spain), using six seed propagated cultivars, three with green heads (‘Imperial Star’, ‘Symphony’ and ‘Madrigal’) and three with purple heads (‘Opal’, ‘Opera’ and ‘Concerto’). On 21 July 2010 the potted plants were transplanted into a sandy loam soil, in lines 1.70 apart and 0.825 m between plants. Plants were sprayed three times every two weeks with GA3 at concentrations 0, 30, 60 and 90 mg L-1, starting on the 10 September. A foliar fertiliser was added at 0.1% (v/v) GA3 solution. In both green and purple head artichoke cultivars it was observed that the earliest cultivars need a lower concentration of GA3 (between 30 and 60 ppm) to produce in autumn, while late cultivars need highest concentrations of GA3 (90 ppm). In general, the greatest final yield was achieved by the control and the highest concentrations of GA3 induced to a lowering final yield, especially in the earliest cultivars. This reduction was also observed in late cultivars (‘Concerto’ and ‘Madrigal’) with the highest concentration (90 ppm). The largest GA3 concentrations produced initially a greater growing and an erect aspect of plants. On the contrary, the highest plant height was noticed in plants sprayed with the lowest concentrations of GA3 and in control plants., Thanks to Conselleria de Agricultura Pesca y Alimentación for the financial assistance in this study, which is included in the developed research for Programa Hortofrutícola, an I+D+i project

Chufa (Cyperus esculentus L. var. sativus Boeck.) is an important vegetable crop in Valencia (Spain), where its tubers are used to produce a refreshing drink called ¿horchata¿. Water is relatively inexpensive, there are no data regarding the volumes of water used to grow chufa, and the irrigation water use efficiency (IWUE) has neither been determined. The aim of this research was to compare the productive responses of the chufa crop to two irrigation strategies (IS). The volumetric soil water content (VSWC) was monitored with capacitance sensors. Trends in VSWC were used to determine the in situ field capacity (FC), beginning each irrigation event when the VSWC reached either approximately 45% (H1) or 60% (H2) of the FC at a soil depth of 0.10 m. The experiments were conducted over three consecutive seasons. An area velocity flow module measured the water flow. The yields, the water volumes used, and the IWUE were calculated. Plants were periodically sampled and the harvest index and relative growth rate were determined. The yield was affected by the year and by the IS. The greatest yields were obtained with the H2 strategy (on average 2.18 kg m¿2 for H2 vs. 1.94 kg m¿2 for H1; p ≤ 0.01), and the average tuber weight (ATW) was affected (p ≤ 0.01) by the year and IS interaction. IWUE was affected by the year, and none of the considered factors affected the harvest index (p ≤ 0.05). It can be concluded that maintaining a higher VSWC would increase both yield and ATW without affecting IWUE., This study was funded by the Regulatory Council of Denomination of Origin Chufa of Valencia of Spain.

The most interesting artichoke production period in the Spanish Mediterranean Coast is autumn-winter. Seeds of seven cultivars ('Imperial Star', 'Alberca', 'Harmony', 'Concerto', 'Madrigal', 'Opal' and 'Lorca') and five lines ('DS-1000', 'DS-2000', 'AR-1', 'AR-2' and 'AR-3') were sown in polystyrene trays on the 14th June 2005 and planted on the 1st August in south Valencia, Spain. 'Blanca de Tudela' and 'Violeta de Provenza', which are asexually propagated cultivars, were planted in the same date and used as controls. Three replicates of 10 plants per cultivar/line were arranged in a completely randomized design. All cultivars and lines were sprayed three times between 20th September and 20th October 2005 with gibberellic acid at 30 mg L-1. Harvest started in October for 'Blanca de Tudela' and among seed propagated cultivars/lines, 'Imperial Star' and 'Lorca' (beginning harvest in November) were the earliest, while 'Concerto' and 'Madrigal' (beginning harvest in February) were the latest. At the end of February 2006, 'Imperial Star' (0.72 kg m(-2) of market yield), 'Blanca de Tudela', 'Lorca' and 'DS-1000' (0.66 kg m(-2) for all three), were the most productive varieties. The highest total market yields (until the end of May 2006) were obtained in 'Madrigal' (2.28 kg m(-2)), 'Concerto' (1.86 kg m(-2)), 'AR-3' (1.77 kg m(-2)) and 'DS-1000' (1.69 kg m(-2)). Whereas the highest non-marketable yields were reached by 'AR-2' (1.05 kg m(-2)), 'AR-3' (0.84 kg m(-2)) and 'DS-2000' (0.78 kg m(-2)). Furthermore at the end of the experiment (end of May), there were not differences among cultivars/lines, for the variable head size (between 91 and 157 g), however some statistically differences during some controls made over the productive cycle were detected for this parameter.

Most of the interspecific rootstocks (Lycopersicum esculentum ¿ L. hirsutum) used in grafted Spanish tomato crops are resistant to Meloidogyne nematodes, but the `Mi¿ resistance gene does not work well at high soil temperatures. Ralstonia solanacearum is a bacterial disease usual in tropical areas, but recently identified with low incidence in several European countries. This disease could be controlled by grafting tomato on Solanum torvum, which is also resistant to Meloidogyne. However, S. torvum and tomato have low grafting affinity, which could be improved using an intermediate rootstock. Some cultivars of eggplant have a relatively good affinity with tomato and complete affinity with S. torvum. In this study we compared two tomato cultivars (one resistant to Verticillium dalihae, Fusarium oxysporum v. lycopersici race 2 and Meloidogyne spp., and one non-resistant) grafted onto `Beaufort¿ (Lycopersicum esculentum ¿ L. hirsutum), `Torvum Vigor¿ (Solanum torvum) and also with an intermediate grafting of eggplant (`Cristal¿) between tomato and S. torvum, with non-grafted plants as controls. This arrangement was carried out in two cropping cycles (winter-spring and summer-autumn). In both cycles, plants grafted onto S. torvum, both single or double grafted, yielded less than those grafted onto `Beaufort¿ or non-grafted plants. In the spring cycle, no differences were found between single and double-grafted plants using S. torvum rootstocks, but in the autumn cycle double grafted plants had higher yields than the single grafted plants. The severity of nematode infections, in terms of reducing yields, and/or hypothetical infections of Ralstonia, will determine the utility of this technique in tomato production.

[EN] The efficiency of fertilisation in agriculture is often low, and if one knows the nutrient uptake rate, efficiency can be improved by synchronizing nutrient supply with nutrient demand. Growth and the time-course of nutrient accumulation and its partitioning between the different organs of chufa (Cyperus esculentus L. var. sativus Boeck.), an under-exploited cultivated plant, were examined. The study was conducted in soilless, open-field conditions, at a planting density equivalent to 55,500 plants ha-1 in three consecutive seasons. Plants were sampled, fractionated into leaves, roots, and tubers, then dried and weighed. Their macronutrient contents were analysed fortnightly. On average, the yield was 5.0 kg fresh weight tuber m-2 . Growth of the whole plant until 90 d after planting obeys an exponential function of time; the relative growth rate (RGR) for this period was determined. The highest N and K concentrations were recorded in leaves, and the highest P, Ca and Mg concentrations were found in roots. The highest accumulations of N and P were found in tubers, and of K and Ca in leaves. Nitrogen had the highest nutrient accumulation (58.3 g m-2 ) as well as the highest specific uptake rate., This study was funded by the Consejo de Denominacion de Origen Chufa de Valencia, Spain. The authors thank the agricultural engineers, Juan Andres and Ramon Ballester, for assisting with the previous experiments, and Debra Westall for revising the manuscript.

[EN] To determine their influence on leaf tipburn incidence and yields six nutrient solutions with different proportions of potassium (K), calcium (Ca), and magnesium (Mg) were tested in ‘Camarosa’ strawberry plants. Response models were made to predict tipburn incidence, yields and fruit weight. A high Ca proportion in the nutrient solution was determinant for high yields in the first season, while a high Mg content was fundamental for high marketable yields during the two last seasons. In 2001 and 2002, the average fruit weight was higher with high Mg levels, and in 2000 the lowest fruit weights coincided with low levels of Ca in the nutrient solution. The models for tipburn incidence in 2000 and 2002 indicated that solutions with intermediate to high levels of Mg and intermediate to low levels of Ca resulted in a more frequent incidence of tipburn. Conversely, in 2001, the highest tipburn incidence appeared with high K contents.

[EN] Plugs of the strawberry cultivar ‘Camarosa’ were rooted in peat:perlite (5:1) substrate and placed at high (HE, 802 m) or low (LE, 10 m) elevations at the end of July. Then they were planted as rooted plants in a Venlo-type greenhouse in perlite bags on 22 September and on 17 October 2006. Before the first planting date, half of the plants from LE were kept at 4°C for two weeks to compare with the other treatments. Early fruit yield was higher with HE plugs planted in October and significantly lower with LE plugs planted in September. No significant differences were found for total yields. Fruit weight was significantly higher with HE plugs planted in October both for early and total production. The extra chilling of September LE plants increased early yields, which were not significantly different from those of HE plants planted in September., The authors acknowledge financial support by the "Ministerio de Educación y Tecnología"-FEDER, research project AGL2004-04365/AGR as well as the linguistic revision by Debra Westall

Three Italian-type sweet pepper cultivars, ‘Palermo’, ‘Estar’ and ‘Charly’, grown in rockwool, were subjected to CO2 enrichment up to 500 and 800 µL L-1 and compared with the natural concentration. Plant growth, measured as plant height, stem diameter, number of leaves and leaf area, was higher in the CO2enriched greenhouses. CO2 enrichment leads to a higher yields in all cultivars, particularly at the highest concentration. Average fruit weight at 800 µL L-1 was higher than in the other treatments, while blossom-end rot incidence was lower in the control plants and higher in plants with CO2 enrichment, especially at 500 µL L-1. The CO2 enrichment resulted in a significant improvement in water use efficiency, both for marketable and total production.

The seed propagated artichoke is sometimes used in Spain to extend the cropping season into the summer months, as with the most used cultivar, the asexually propagated ‘Blanca de Tudela’, the crop finishes at the end of May or the beginning of June. It is also possible to fill a similar cycle of the ‘Blanca de Tudela’ during autumn and winter with gibberellic acid (GA) treatments. The use of mulching is an interesting technique to reduce water consumption and herbicide utilization. This technique is of great importance within the concept of sustainable agriculture. The agronomical effects of the mulching film system (black polyethylene and co-extruded polyethylene (white and black) and the non-mulching system have been compared on artichoke (cv ‘Imperial Star’) from seed in two cycles. Within the spring cycle, two transplanting dates (6th February and 9th March) have been studied. Within the autumn cycle, only one date (12th July) has been studied, spraying the plants with GA. The spring cycle turned out to be less productive than the autumn one. In the spring cycle no differences in yield were detected but head weight was higher with black polyethylene mulching. In the summer transplant, the use of black polyethylene mulching film increases the post-transplant failure of plants and has a slowdown effect on plant growth, significantly reducing yields. No differences were observed in external quality parameters.

In Spain, the artichoke crop is interesting for autumn-winter production. With vegetative propagated cultivars, like ‘Blanca de Tudela’ or ‘Violeta de Provenza’, the harvest starts at the beginning of autumn and finishes at the end of spring. The currently available seed propagated cultivars are not as early as the asexually propagated ones mentioned above. For this reason, to obtain production in the autumn-winter cycle with seed propagated cultivars, it is necessary to use the earlier ones, to plant at the beginning of the summer and to spray plants with gibberellic acid (GA) to substitute the lack of vernalization requirements. The trials were conducted during three seasons. In 1999-2000, using the cultivar ‘A-106’ and ‘A-108’, two concentrations of GA (10 and 30 ppm) were compared with untreated plants. In the 2000-2001 season, using the cultivars ‘Lorca’ and ‘Nun 98465’ and in the 2001-2002 season, using the cultivars ‘A-106’ and ‘Nun 9409’, three concentrations of GA (10, 30 and 50 ppm) were also compared with untreated plants. The cultivars ‘A-106’ and ‘Lorca’ are similar to Imperial Star and earlier than the hybrids ‘Nun 98465’ and ‘Nun 9409’. In the earlier cultivars, GA applications increased early yields. No significant differences in yield or head weight were found among the GA concentrations tested. In the latest cultivars (‘Nun 98465’ and ‘Nun 9409’), higher concentrations of GA slightly increased early yields, but not high enough to be comparable to the earlier ones.

Research was conducted over three seasons (1996-97, 1997-98 and 1998-99) to determine the productive potential of green pods in first-year plants, studying two different production cycles, using a local accession of the botanic variety albiflorus D.C. of Dolichos lablab L. (Egyptian Bean). In the first experiment (1996/97), cropping was done in pots with peat substrate in a polyethylene greenhouse, the transplanting dates were 17th September (F1) and 21st January (F2). In the other two experiments cropping was done in a sandy loam soil in glasshouses; in the second experiment (1997/98) the transplanting dates were 20th October (F1) and 2nd January (F2) while in the third experiment (1998/1999) the transplanting dates were 17th September (F1) and 11th January (F2). Plants were placed in rows 1 m apart with 0.5 m between them. Plants were staked and tied. The immature pods were harvested twice a week. The accession used in these experiments adapted well to protected cultivation. The green pod yields obtained (95200 kg ha-1) are much higher than those reported for beans under identical growing conditions in the field (28000 kg ha-1). Transplanting in September allows for high-yield, green pod harvesting year-round, even in autumn and winter. Continued experiments are necessary to determine the performance of this plant in subsequent years.

The effect on fruit quality of grafting and fruit set treatments, was determined in the triploid watermelon (Citrullus lanatus (Thun.) Matsum. and Nakai) cultivar 'Reina de Corazones' grown in a heated greenhouse. Grafting the scion onto 'Shintoza' (Cucurbita maxima X Cucurbita moschata) rootstock and setting fruit through application of the synthetic cytokinin CPPU [1-(2-chloro-4-pyridyl)-3-phenylurea] retarded the accumulation of sugar and development of the flesh colour of the fruit, compared to fruit from non-grafted, pollinated plants. The effects of grafting and of CPPU application on sugar accumulation were additive. At commercial maturity, the fruit of grafted and/or CPPU-treated plants had lower total soluble solids and sugar concentrations, and lower sucrose to hexose ratios, than fruit from control plants. Fruit from CPPU-treated plants also had a weaker red colour than fruit set by pollination. Despite this loss of quality, fruit from grafted plants, set with CPPU and grown in a heated greenhouse, had a total soluble solids concentration similar to fruit from pollinated, non-grafted plants, grown outdoors.

[EN] Yield and fruit characteristics of grafted plants of the 'Reina de Corazones' watermelon cultivar (Citrullus lanatus (Thunb.) Matsum and Nakai), grown in Fusarium-infestated soils, were determined in a series of experiments performed in the 8-year period 1993-2000. The experiments were performed in the coastal area south Valencia, Spain, in soils with a clay content ranging from 16 to 38%. Plant survival and yield were the highest in plants grafted onto several Cucurbita maxima x Cucurbita moschata hybrids and onto 'Jover' and 'Bodi 1' C. moschata cultivars. The survival ratio of the plants grafted onto 'Shintoza' rootstock (C. maxima x C moschata) was 93%, while the mean yield in an early production cycle with harvests extending from the end of June to mid-August was 89,000 kg ha(-1). The 'Shintoza' rootstock increased fruit size compared to the non-grafted plants, and improved yield stability by decreasing the coefficient of variation to 20%. The use of 'Shintoza' rootstock had no effect on the soluble solids concentration of the central endocarp, and did not increase the development of yellowish bands in the flesh or the internal breakdown of the endocarp. The use of this rootstock is an advantageous alternative to soil fumigation by methyl bromide for the control of Fusarium, wilt in watermelon production, as it is cheaper and safer, and the yields are higher and more reliable. (C) 2004 Elsevier B.V. All rights reserved., We thank Conselleria de Agricultura, Pesca i Alimentació, Generalitat Valenciana, and Fundación Ruralcaja for financial support.

This two-year study (1999-2000) analysed the effects of three factors on the germination of caper seeds: the fruit position on the mother plant, the fruit maturation stage and the unit fruit weight. Plants of cultivar Comun were grown in Valencia, Spain. Ripe fruits were collected in September and early October. Mature dark brown seeds were selected. Germination tests were performed in closed Petri dishes in a growth chamber. Germination data were fitted to the logistic function and variables such as the maximum germination percentage; the time to reach 50% of final germination and the mean relative cumulative rate were calculated. The results indicate that the use of the logistic function is adequate to analyse the germination of caper seeds. The final germination percentage was affected by. fruit position and unit fruit weight, but not by the fruit maturation stage. The best results, over 90%, were obtained with fruits of large or medium size and with fruits set in the central or apical region of the branches. The time to reach 50% of final percentage and the mean relative cumulative rate were not affected by the factors studied. There were marked differences between the average values of these variables corresponding to the two years studied.

Research was conducted over two seasons (1997-98 and 1998-99) to determine the productive potential of green pods during the first and the second year plants, studying two different sowing dates and using a local accession of the botany variety albiflorus D.C. of Dolichos lablab L. (Egyptian bean). Cropping was done in a sandy loam soil under a glasshouse. Sowing was done in mid-September and midDecember 1997 in trays with peat. Harvesting began in March and April 1998 respectively in the first season, and in November 1998 (in both sowing dates) in the second season. The pods were harvested in an immature state twice a week and then counted and weighed. The accumulated autumn-winter-spring yields were higher with the second-year plants, but later yields were similar to those of the one-year old plants, and in both cases very high, up to 4.76 kg per plant. No significant differences in average pod weight were detected between both types of plants in study. The autumn-winter yields were higher with the earliest sowings.

To find techniques to improve root system development of waiting-bed strawberry plants ‘Camarosa’ grown in substrates, the influence of two substrates (peat and coconut coir dust), or plants from three waiting-beds at different altitudes, and of root treatments with different plant growth regulators (naphthalenacetic acid at 25, 50 and 75 mg g–1; indolebutyric acid at 10, 20 and 30 mg g–1; l-triacontanol at 0.02, 0.04 and 0.06 mg g–1) by dipping runners prior to planting, were studied in two experiments in the 1997–98 and 1998–99 seasons. In both years, plants from high elevation beds (HE) produced the greatest root development, and plants from medium elevation beds (ME) produced more new roots than those from low elevation beds (LE). Root development of plants grown in peat was greater than those grown in coconut coir dust in the first experiment and only on the first measuring dates (one month after planting). This difference was particularly high in plants from high or medium elevation nurseries, when the degree of root development was greater. No differences between substrates were observed in the second experiment. Treatments with the different growth regulators tested, at any of the concentrations used, did not improve root development on average for the other factors.

This study addresses vegetative growth and the uptake of nutrients and their accumulation in the vegetative and reproductive tissues of pepino (Solanum muricatum Ait.). The study was conducted in soilless plastic house conditions, with a planting density equivalent to 25 000 plants ha(-1) during two seasons (1997-98 and 1998-99). The plants were sampled, fractionated into leaves, stems, fruits and roots, then dried and weighed and the macronutrient content was analysed every 30 d for 300 d after transplanting. The yield obtained was 2 kg of fruit per plant, which is 30% of the total dry weight. The relative growth rate (RGR) ranged from 0.0028 to 0.0451 d(-1). The highest N, K, Ca and Mg concentrations were recorded in the leaves, and the highest P concentration in the roots. The nutrient accumulation of this yield was 10.64, 1.12, 16.06, 10.0 and 1.58 g of N, P, K, Ca and Mg per plant respectively. The highest accumulation of all nutrients was found in the leaves. The nutrient with the highest specific uptake rate was K, which ranged from 0.0037 to 0.0838 g g(-1) d(-1).

[EN] Tubers of Cyperus esculentus were an important food in ancient Egypt. in Spain the tubers are used to make a beverage named horchata, and are also consumed as fresh after soaking. in other countries tubers are used in sweetmeats or uncooked as a side dish. New products obtained can enhance the interest in this crop: as a source of dietary jiber in food technology; as a high quality cooking/salad oil or as biodiesel fue/; as caramel to add body, flavor or color to other products; as a source of starch; as an antioxidant-containing food, etc. The results of a twenty-year research program on nutrition, fertilization, lodging control, planting date, soil texture and use of herbicides are shown. Three cultivars ( 'Ametlla Bonrepos', 'Gegant Africana', and 'Llargueta Alboraia' ) are selected and characterized using horticultura/ and morphological traits, the chemical composition of tubers and horchatas, and the RAPD technique., [ES] Los tubérculos de Cyperus esculentus, que fueron un importante alimento en el antiguo Egipto, se utilizan, en España, para obtener una bebida refrescante denominada horchata y para consumo en fresco. En otros países se consume como entremés y en confitería. Su interés podría incrementarse con la obtención de nuevos productos de aplicación como materia prima en tecnología de alimentos (fibra; aceite de gran calidad, sustitutivo del aceite de oliva; aditivos de sabor, color y cuerpo; almidón; capacidad antioxidante), como combustible biodiesel, etc. Se presentan los resultados obtenidos en veinte años de investigación en aspectos agronómicos (nutrición, fertilización, control del encamado, fecha de plantación, textura del suelo y utilización de herbicidas) y de selección y caracterización varietal (características morfológicas y agronómicas, composición química de tubérculos y horchatas, utilización de la técnica RAPD), que han permitido la selección y caracterización de tres cultivares: 'Ametlla Bonrepos ', 'Gegant Africana', y 'Llargueta Alboraia '

Concurrently with studies about the behaviour of waiting-bed plants for winter production in Spain, we studied the influence of the number of crowns of these nursery plants and how they affect both production and fruit quality. This study was carried out in 1995 using multicrown plants of cvs Chandler, Oso Grande, Pajaro and Vilanova, from a low elevation nursery, which were divided into 5 groups having 1, 2, 3, 4 and 5 crowns. Planting occurred on December 27, 1994 in a large polyethylene tunnel. Vegetative parameters as well as production and fruit weight were measured. Production started at the begining of March. Crown number did not affect production in ‘Oso Grande’ or in ‘Vilanova’, but in ‘Chandler’ there was a linear increase in production with crown number and in ‘Pajaro’ a quadratic effect occurred. Fruit weight decreased linearly with crown number in ‘Oso Grande’ and ‘Vilanova’, and was not affected in ‘Chandler’ or ‘Pajaro’. The number of flowers and fruits in the middle of February increased with crown number, having significant linear and quadratic effects in ‘Chandler’, ‘Pajaro’ and ‘Vilanova’, but crown number had no effect in ‘Oso Grande’.