Phenotypic yield and its structure variability of moderately late and late potato cultivars

The breeding of new potato cultivars of a given earliness group is closely related to the knowledge of the range of variability and interdependence of traits in a given year and between years. The research results were based on the field experience conducted in 2010–2012, in Central-Eastern Poland (51°34'N, 23°02'E), on lessive, slightly acidic soil. The experiment was carried out in a randomized block design in triplicate. Seventeen medium late and late potato cultivars were tested. Agronomic and plant protection treatments were carried out following the principles of good agricultural practice. The variability of potato economic characteristics was assessed through variance analysis, variance component analysis, cluster analysis, and principal component analysis (PCA). The years of research (52.5–94.6%) have played a dominant role in the phenotypic variability of general yield, commercial and seed yield, and their structure. The genetic factor was from 1.3 to 24.1%, and the interaction of the cultivar × years – from 3.1 to 61.7% of the variance share in the total variance. The analysis of the main components has identified four groups of cultivars with specific properties. They can be used in the decision-making system of breeding the new potato creations.

Thirty years of the PROINPA Foundation's contribution to Bolivian agriculture: Case of “Marcela” potato crop

With the objetive of recognizing Bolivian researchers, who are not always mentioned, we have written this simple but significant document, in which the case of potato cultivation “Marcela”, which is being widely used in the valleys from Tarija and Potosí heights mainly, due to its tolerance to drought, resistance to late potato blight (Phytophthora infestans) and precocity, with yields ranging from 15 to 20 t ha-1. This cultivar was assumed by INIAF as an alternative strategy to deal with reducing the effects of climate change on potato production.

Analysis of potate quality: In vitro versus clonal propagation

Potato, one of the most important food crops in the world, is susceptible to viruses, which reduce its yield and production efficiency. The resistance of potatoes to viral infection is an essential factor in the preservation of the variety’s productive qualities. In addition, there are several ways of selection for recovering and obtaining the initial seed material that is free from viruses for further reproduction in the seed growing of potatoes. It should be noted that in the literature the issues of medium-late potato varieties resistance to viral diseases in the Forest-Steppe zone of Ukraine are not fully covered, which has become the subject of our research. In our studies we used the material obtained by the method of improving selections, as well as using thermotherapy and apical meristem culture. Over the years of reproduction both meristematic and seed material from improving selections, the virus infestation in plants wasn’t changed significantly, provided that all seed growing events were observed. It has been proven that the yield of super-super-elite of Lybid variety is not significantly changed depending on the method of obtaining the initial material. The variety Gorlitsa has higher yield in the plantations formed by clonal propagation. It has been established that the yield of variety Lybid super-elite varies, but not significantly, depending on the method of obtaining the initial material. The variety Gorlitsa has a higher super-elite yield when using the initial material from clonal propagation in breeding nurseries with use of improved selections. Significant influence on the manifestation of the sign, both in the cultivation of super-super-elites and super-elites, has the weather conditions of the year and the biological characteristics of the variety. In 2017, the highest yield of tubers was obtained at Gorlitsa – 3.74·104 kg ha-1, at Lybid the lower yield was 2.43·104 kg ha-1. In 2018, the highest yield of tubers was formed by Lybid variety – 3.50·104 kg ha-1, and the lowest was byt Gorlitsa variety – 2.56·104 kg ha-1.

Effects of potassium fertilisation on late potato blight and yield – short communication

Potato yields and infestation by P. infestans are related to the supply of potassium. Potassium was applied as soil fertilisation combined with split foliar applications or only as split foliar treatments at a maximum dose of 150 kg/ha K₂O in both strategies, Lord and Ditta cultivars were used. Additionally, water spraying was included as an alternative treatment in order to maintain uniform moisture in the rows of plants. Plants fertilised with foliar spraying only were more infested than plants fertilised with combined methods. The fertiliser increased the protection impact of copper treatments against P. infestans. This may suggest a possible synergistic effect in reducing the symptoms of the disease, however not always statistically significant in both cultivars. Plants sprayed with water but without soil application of fertiliser showed a statistically significantly higher infestation rate, both in Lord and Ditta cultivars, compared to plants with soil application of fertiliser but without watering.

Mitochondrial targeting of glycolysis in a major lineage of eukaryotes

Glycolysis is a major cytosolic catabolic pathway that provides ATP for many organisms1. Mitochondria play an even more important role in the provision of additional cellular ATP for eukaryotes2. Here, we show that in many stramenopiles, the C3 part of glycolysis is localised in mitochondria. We discovered genuine mitochondrial targeting signals on the six last enzymes of glycolysis. These targeting signals are recognised and sufficient to import GFP into mitochondria of a heterologous host. Analysis of eukaryotic genomes identified these targeting signals on many glycolytic C3 enzymes in a large group of eukaryotes found in the SAR supergroup3, in particular the stramenopiles. Stramenopiles, or heterokonts, are a large group of ecologically important eukaryotes that includes multi- and unicellular algae such as kelp and diatoms, but also economically important oomycete pathogens such as Phytophthora infestans. Confocal immunomicroscopy confirmed the mitochondrial location of glycolytic enzymes for the human parasite Blastocystis. Enzyme assays on cellular fractions confirmed the presence of the C3 part of glycolysis in Blastocystis mitochondria. These activities are sensitive to treatment with proteases and Triton X-100 but not proteases alone. Our work clearly shows that core cellular metabolism is more plastic than previously imagined and suggests new strategies to combat stramenopile pathogens such as the causative agent of late potato blight, P. infestans.

Impact of meteorological drought on crop water deficit and crop yield reduction in Polish agriculture

The study presents the quantification of the effect of meteorological drought on crop water deficit and crop yield reduction in different agro-climatic regions of Poland. The regression equations describing the relationship between the standardized precipitation index SPI (meteorological drought) and the crop drought index CDI (evapotranspiration reduction) were used in a first step. Then the FAO equation describing the relationship between CDI and yield reduction was used. Crop water deficit measured by CDI is spatially differentiated and depends on the intensity of meteorological drought and soil water availability. The greatest evapotranspiration reduction is found for late potato growing in the central-west Poland (30-60%). The smallest reduction of evapotranspiration was stated for winter rape (12-16%) in the same region on soils with small water retention and no reduction can be on soils with large water retention. A good correlation between estimated and observed yield reduction was found. Potential yield reduction of late potato can reach more than 50% in central Poland. Least yield reduction is for winter wheat and winter rape. The main advantage of the method used in the study is the combination of meteorological drought, soil water retention capacity, evapotranspiration, soil water balance and crop yield, and so help provide more accurate assessments.

The effect of mineral fertilization on fungi colonizing potato (Solanum tuberosum L.) tubers after harvest and after storage

The paper presents the results of a three-year exact experiment conducted in Bałcyny, in which a late potato cultivar, Jasia, was grown. The objective of the study was to determine the effect of different levels of mineral fertilization: A (N 80 kg × ha^-1 P 80 kg × ha^-1 K120 kg × ha^-1) and B (N 120 kg × ha^-1 P 144 kg × ha^-1 K156 kg × ha^-1), and foliar fertilization (Basfoliar 12-4-6, ADOB Mn and Solubor DF) on the quantitative and qualitative composition of fungal populations colonizing potato tubers. Fungi were isolated immediately after harvest and after a five-month storage period. After seven days of incubation, fungal colonies were transferred onto agar slants for microscopic identification. Over the entire experimental period, more pathogenic fungi were obtained from potato tubers analyzed after storage (62.9% of the total fungal population after storage) than from those analyzed immediately after harvest (39.1%), and the greatest number of fungi was reported in 2004. <i>Rhizoctonia solani</i> was isolated most frequently, followed by <i>Colletotrichum coccodes</i> and <i>Alternaria alternata</i>. Pathogens of the genus <i>Fusarium</i> and the species <i>Helminthosporium solani</i> were not numerous. In the treatment A with soil mineral fertilization with lower NPK rates, larger numbers of pathogenic fungi were noted in 2004 after harvest and after five-month storage, and in 2005 after harvest. At the remaining dates of analysis, pathogens were more frequently isolated from potato tubers in experimental variant B with higher NPK rates. Immediately after harvest, the highest number of pathogenic fungi was isolated in the treatment with foliar application of ADOB Mn and Basfoliar 12-4-6. After five-month storage, pathogens most often colonized potato tubers in experimental variant B with foliar application of Solubor DF, Solubor DF and ADOB Mn, and in experimental variant A with a combination of fertilizers. In the other fertilization variants, including in the control treatment, the population size of pathogenic agents remained at a similar level.

El nuevo seguro de ingresos de la patata: Una evaluación preliminar

In 2003 and 2004, an insurance product that protects against market risks of agricultural commodities was offered in Spain. It consists on a revenue insurance product which has been launched as a pilot program for mid-season and late potato in five Spanish provinces (Álava, Burgos, La Rioja, León and Valladolid). The objective of this article is to describe the characteristics of this insurance product and to perform a preliminary evaluation of the seasons it was marketed. We start from a conceptual approach to the market risk management instruments, that constitute the context for the current program. Later, we explain the price model used to define market reference prices and the premia, checking the quality of the statistical price model against the potato farm-gate prices. Finally, the article ends with a preliminary valuation/ assessment of this first pilot experience in Spain, stressing those aspects which are liable/prone to be improved and reckoning the possible extensions of this insurance line to other potato varieties, provinces and also to other agricultural commodities.