Biomass, nitrogen and potassium dynamics in hydroponic rose production
Daniela Alvarado-Camarilloa, Luis A. Valdez-Aguilar a, Ana María Castillo-Gonzálezb, Libia I. Trejo-Téllezc and
Silvia Y. Martínez-Amadord
aDepartamento de Horticultura, Universidad Autónoma Agraria Antonio Narro, Saltillo, México; bDepartamento de Fitotecnia, Universidad Autónoma Chapingo, Chapingo, México; cPrograma de Edafología, Colegio de Postgraduados, Montecillo, México; dDepartamento de Botánica, Universidad Autónoma Agraria Antonio Narro, Saltillo, México
ABSTRACT
Purpose: Roses are one of the ornamental species of major importance and economic value. Fertilisation programmes which maximise plant growth and quality, while minimising environmental impact are important. Here, we followed the N and K dynamics during rose development with the aim to define the nutrient demands as a basis for implementing
fertigation programmes.
Materials and methods: Roses with one basal break were grown in a closed hydroponic system. Destructive samples were taken to determine dry weight, N and K content. In each sample, plants were sectioned into roots, rootstock, basal break, stems and leaves from the zone of active leaves and the zone of cutting flowers, as well as the flower bud in the latter.
Results: The shoots of the active leaves and cutting flowers zones exhibited a biphasic growth; dry weight, N and K increased after pruning of the zone of active leaves and the cutting flowers zone, however, in the second phase, total dry weight did not show a significant difference between the phenological phases, while the accumulation of N and K decreased throughout the entire plant.
Conclusions: Our results suggest that greenhouse roses develop a dynamic and complex balance between the aerial parts of the plants and the roots for storage and/or transport of photoassimilates, N and K. The total demand for N was 411 and 799 mg per plant for the initial shoot development of the active leaf zone and cutting flowers zone, respectively. The demand for K was 149 and 106 mg per plant for both shoots, respectively. The loss of N (555 mg per plant) and K (167 mg per plant) from roses plants to the root environment implies that lower fertiliser inputs can be used as these nutrients may be re-uptaken by new emerging roots.
KEYWORD S
Fertiliser use efficiency; mineral nutrition; Rosa sp; cyclic growth; ornamentals
Can within field yield variation be explained using horizontal penetrometer
resistance and electrical conductivity measurements? Results from three Swedish
fields
Elisabeth Böleniusa, Johanna Wetterlindb and Thomas Kellera,c
aDepartment of Soil & Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden; bDepartment of Soil & Environment, Swedish University of Agricultural Sciences, Skara, Sweden; cDepartment of Agroecology & Environment, Agroscope, Zürich, Switzerland
ABSTRACT
Spatial variations in yield occur in all agricultural fields to some degree. Knowledge of the reasons for these variations, especially temporally stable yield patterns, is needed in order to improve productivity by changing production methods or inputs. This information must be provided in a simple, cost-effective way. This study investigated whether field-scale measurements of
penetration resistance (PR) could identify temporally stable yield patterns without complementary measurements of other properties. The PR measurements were also compared with field-scale apparent electrical conductivity (ECa) measurements and correlations between yield and PR and yield and ECa were investigated. Measurements with a newly constructed horizontal penetrometer and a non-invasive proximal electromagnetic induction sensor were carried out in three fields in east-central Sweden. The measurements were made once in each field, apart from one field where PR was measured twice in one season. The sensor measurements were compared with crop yield measured over the course of several years. The horizontal penetrometer was able to identify low-yielding areas in one field. However, single measurements of PR or ECa were insufficient to consistently identify yield variations. Parts of the fields showed more consistent patterns, with stronger correlations between PR, ECa and yield. PR and ECa data were better at explaining yield variations in drier years, but showed diverging patterns in different fields and neither showed a much stronger correlation to yield than the other. In future studies, simultaneous measurement of soil water content is recommended and also PR measurements at a water content drier than field capacity.
KEYWORD S
Penetration resistance; electrical conductivity; spatial variation; yield; soil physical properties; temporally stable patterns
Evaluating crude extracts of Monsonia burkeana and Moringa oleifera against
Fusarium wilt of tomato
Mapula Tshepo Pertunia Hlokwe, Mapotso Anna Kena and Ndivhuwo David Mamphiswana
Department of Plant Production, Soil Science and Agric, Engineering, University of Limpopo, Limpopo, South Africa
ABSTRACT
Fusarium wilt is one of the major soil-borne diseases of tomato crop globally. The study aimed to evaluate the efficacy of medicinal plants in the control of Fusarium wilt in tomato. Methanolic extracts of Monsonia burkena and Moringa oleifera were assessed in vitro and under greenhouse conditions. The in vitro experiments evaluated the effect of both extracts on Fusarium oxysporum f. sp lycopersici growth and response to varying concentrations. In greenhouse experiment, tomato seedlings cv. HTX14 were inoculated with conidial suspension of F. oxysporum and transplanted into pasteurised growth media amended with plant extract. Seedlings were treated with aqueous extracts at varying concentrations with an interval of 7 days between applications. Control treatments were treated with sterile distilled water. Both plant extracts significantly reduced pathogen growth in vitro and reduced wilt severity under greenhouse conditions. The highest mycelial growth suppression was observed in Mon. burkeana treatments. Under greenhouse conditions, both plant extracts significantly (P ≤ 0.05) reduced Fusarium wilt severity and had a positive effect on plant growth parameters. A significant increase in soil-pH was also recorded in extract treated soil resulting in reduction in disease severity. The results further provide new scientific information on how their effect on soil pH can be beneficial in the control of Fusarium wilt.
KEYWORD S
Disease severityFusarium oxysporum f.sp lycopersici; pathogen growth; plant extracts; soil Ph
Evaluation of hybrid and population cultivars on standard and high-input
technology in winter oilseed rape
Wenda-Piesik Anna and Hoppe Szymon
ABSTRACT
The problem raised here is the intensification of technology in field crops of winter oilseed rape. Is there a justification for this by explaining what relationship between the yield and individual yielding traits are formed in hybrid and population cultivars. During years 2012– 2015 field studies to evaluate five hybrid and five population cultivars response on the standard and highinput technology in winter oilseed rape production have been executed in Poland. High-input technology included: double foliar application (in autumn, and in spring) of micro-nutrients, additional top fertilisation of 40 kg N per ha in spring, double application of the amino-acid biostimulators, and additional growth regulator. According to the principle component analysis
made for both technologies it was found that hybrids and population cultivars displayed varied response which is explained here on the basis of morphological, growth, and yield elements. The high-input technology improved the yield responded elements e.g. number of siliques and number of seeds per silique as well as winter hardiness. This impact was more evident for population cultivars than for hybrids. We state that high-input technology, as the proposal in this paper, that provided 9.6% increase in seed yield, is biologically justified for winter oilseed rape crop and can be recommended in North and central European countries.
KEYWORD S
Brassica napus var. oleifera; population cultivars; hybrid cultivars; standard technology; high-input technology
Irrigation with salt water affects growth, yield, fruit quality, storability and
marker-gene expression in cherry tomato
Mohamed M. El-Mogy a,b, Cecile Garcheryb and Rebecca Stevensb
aVegetable Crops Department, Faculty of Agriculture, Cairo University, Giza, Egypt; bINRA, UR1052, Génétique et amélioration des fruits et légumes, Domaine St Maurice, Allée des Chênes, 84143 Montfavet, France
ABSTRACT
The use of saline water for plant production will become increasingly necessary over future decades. In some cases, fruit quality such as in tomato, can be improved by irrigation with saline water. The influence of different salt concentrations on physiological responses and the expression of some selected genes of cherry tomato ( Solanum lycopersicum L), cv. West Virginia 106, was examined. Tomato plants were grown in peatmoss substrate and irrigated with 0, 25, 50, 75, 100 or 150 mM sodium chloride (NaCl) in a glasshouse. The NaCl treatments of 75, 100 and 150 mM salt resulted in shorter plants, decreased stem width, a lower plant dry weight, fewer flowers, and smaller leaf area, while yield was reduced by treatment with concentrations of 50 mM NaCl and above. Average fruit weight and fruit number were also negatively affected by treatment with 50 mM salt and above. Salinity treatment led to increased fruit total soluble solids, titratable acidity and firmness and improved the taste index. Salt-responsive marker genes identified in Moneymaker were also induced in cherry tomato but not at the highest salt concentrations. Our results indicated that cherry tomato treated with 25 mM NaCl produced fruit with improved quality in comparison with non-salinized control plants without compromising yield, while at 50 and 75 mM the improved fruit quality was accompanied by a reduction in yield.
KEYWORD S
Solanum lycopersicum; salt; NaCl; postharvest; quality
Leaf gas exchange and water-use effi ciency of dry-land wheat genotypes under
water stressed and non-stressed conditions
Nkhathutsheleni Maureen Tshikundea, Alfred Odindoa, Hussein Shimelisa,b and Jacob Mashiloa,b
aSchool of Agricultural, Earth and Environmental Sciences, Discipline of Crop Science, University of KwaZulu-Natal, Pietermaritzburg, South Africa; bAfrican Centre for Crop Improvement (ACCI), University of KwaZulu-Natal, Pietermaritzburg, South Africa
ABSTRACT
The objective of this study was to determine drought tolerance characteristics of dryland wheat genotypes based on leaf gas exchange and water-use efficiency in order to identify promising genotypes for drought tolerance breeding. Physiological responses of ten genetically diverse wheat genotypes were studied under non-stressed (NS) and water stressed (WS) conditions
using a 2 × 10 factorial experiment replicated 3 times. A highly significant water condition × genotype interaction (P < 0.001) was observed for photosynthetic rate (A), ratio of photosynthetic rate and internal CO2 concentration (A/Ci), ratio of internal and atmospheric CO2 (Ci/Ca), intrinsic (WUEi) and instantaneous (WUEinst) water-use efficiencies suggesting genotypic variability among wheat genotypes under both test conditions. Principal component analysis (PCA) identified three principal components (PC’s) under both test conditions accounting for 84% and 89% of total variation, respectively. Bi-plot analysis identified G339 and G344 as drought tolerant genotypes with higher values of A, T, gs, A/Ci, WUEi and WUEinst under WS condition. The current study detected significant genetic variation for drought tolerance among the tested wheat genotypes using physiological parameters. Genotypes G339 and G344 were identified to be drought tolerant with efficient A, T, gs, A/Ci and water-use under water stressed condition.
KEYWORD S
Breeding; drought stress; drought tolerance; water-use efficiency; wheat
