Correlation between the heterosis of F1 carrot hybrids and the genetic distance of their parental lines

Celem badań było oszacowanie korelacji pomiędzy efektem heterozji mieszańców F₁ a dystansem genetycznym linii rodzicielskich. Doświadczenia obejmujące 15 linii hodowlanych i 34 mieszańce prowadzone były w latach 1998 i 1999. Oceną objęto plon i jego strukturę, poziom karotenu, suchej masy oraz cukrów. Znacząco dodatnie wartości efektu heterozji pod względem plonu ogólnego wystąpiły w 59% badanych mieszańców i w 38% - dla plonu handlowego. Zawartość składników odżywczych w korzeniach spichrzowych pokolenia F₁ była przeważnie na średnim poziomie w stosunku do form wyjściowych, a efekt heterozji występował tu rzadko. Analiza markerów molekularnych przeprowadzona była za pomocą dwóch metod: RAPD i AFLP. Wartości korelacji były istotne między dystansem genetycznym obliczonym dla markerów RAPD a heterozją pod względem plonu ogólnego (r = 0,42*) oraz pomiędzy dystansem AFLP a heterozją pod względem plonu handlowego (r = 0,34*). Uzyskane wyniki wskazują na pewne możliwości przewidywania efektu heterozji pokolenia F₁ w oparciu o odległości genetyczne między liniami hodowlanymi.The aim of this research was to estimate the correlation between the effect of heterosis in F₁ hybrids and genetic distance of their parental lines. The experiment carried out in 1998 and 1999, included 15 inbred lines and 34 hybrids of carrot. The yield structure and content of carotene, dry matter and sugar were evaluated. Significant heterosis occured in 59% hybrids for the total yield, and in 38% - for market yield. Generally, the contents of nutrients in F₁ carrot roots was on the average level as related to used parental lines, and the effect of heterosis was observed rather rarely. RAPD and AFLP markers were used for estimation of genetic distance between parental lines. Significant correlations were found only between analysis based on RAPD markers and heterosis of total yield (r = 0.42*), and between AFLP markers and heterosis of market yield (r = 0.34*). That indicated on same possibility to predict the effect of hybrids heterosis by estimation of genetic distances between parental lines

Improvement of red beet monogerm clusters germination using rubbing and water treatments

The aim of the research was to improve the germination parameters of red beet monogerm clusters using pre-sowing treatments. Red beet (Beta vulgaris L.) clusters of two monogerm breeding lines, AR79A and W411A, differed in the initial germination capacity, were studied. Five seed treatments including rubbing, leaching for 4, 8 and 24 hours, and soaking for 24 hours, were performed. Based on the germination test carried out at 15 and 20ºC, the germination traits, such as the mean germination time (MGT), coefficient of uniformity of germination (CUG), coefficient of velocity (COV), germination capacity (GC) and germination rate (GR), were measured. Compared to the control, treatments used in the study improved the most of measured germination features for both tested lines. The leaching of clusters for 24 hours yielded the best enhancement in most of the germination traits. The rubbing was the least effective technique in terms of improvement in the germination parameters. The germination of treated clusters at 15 and 20°C presented comparable, and better than the control, values of germination features. The interaction between treatment method and germination temperature showed that leaching of clusters for 24 hours and germination at 20°C was the technique that successfully influenced the majority of the germination characteristics. Finally, it was noted that each pre-sowing technique significantly improve germination parameters, however the line AR79A with lower initial GC (65%) presented better improvement of MGT, CUG and GC than the line W411A with higher initial GC (84%)

Influence of planting density of monogerm and multigerm red beet stecklings on the seed stalks characteristics

The aim of this research was to study the effect of stecklings planting density on the seed stalk architecture, cluster yield and seed quality of 20 mono - and multigerm breeding lines and cultivars of red beet. The study included the new monogerm lines - AR79 A and AR79 B - breed in the Unit of Genetics Plant Breeding and Seed Science at the University of Agriculture in Kraków. The experiment was conducted in the years 2010 and 2011, in the open field conditions. Two planting densities of stecklings: 50×25 and 50×40 cm, were applied. Standard crop management practices, as recommended for red beet seed production under Polish conditions, were followed. The increase in plants interspacing from 50×25 to 50×40 cm led to the lower height, but twice higher number of shoots per plant, lower number of single, but higher number of bush and bush with main stem seed stalks, twice higher yield per plant as well higher thousand-seed weight and germination capacity. A large variation between genotypes in the features of seed-bearing plants, such as morphological structure, clusters yield and seed quality, were noted. Compared to other genotypes, the new monogerm breeding lines AR79 A and AR79 B formed very high, mostly bush or bush with main stem seed plants developing one of the largest numbers of unluckily, late-ripening shoots, yielded on the average level and producing the seeds of relatively low quality. The research has expanded the knowledge about the generative development of red beet. The results will facilitate Polish breeding programs aimed at the selection of monogerm red beet lines

Comparison of water needs and precipitation deficiency during the growing season of asparagus in the region of Bydgoszcz and Wroclaw

The aim of the study was to compare the water requirements and the precipitation deficiencies during cultivation of asparagus in the period from June to August in the regions of Bydgoszcz and Wroclaw. The water needs were calculated using the plant coefficient. The reference evapotranspiration was measured by Grabarczyk’s method (1976). The coefficients kc, determined for the Polish conditions by Rolbiecki (2013), were used to estimate the water requirements considered as the crop evapotranspiration. In the studied period (from June to August, 1996-2015), higher water requirements of asparagus were noted in the Wroclaw region (366.1 mm) than in the Bydgoszcz region (288.5 mm). The monthly water needs in June, July and August were 69.8 mm, 128.8 mm and 167.5 mm, respectively, in the Wroclaw region, and 55.5 mm, 98.5 mm and 134.5 mm, respectively, in the Bydgoszcz region. In July, the tendency to increase the water requirements in both observed regions was noted. The monthly crop evapotranspiration in July rose in each decade by 12.3 mm in the Bydgoszcz region and by 21.2 mm in the Wroclaw region. In the 20-year study, the rainfall deficit in June and July during 11-13 years was noted. In August, the precipitation deficiencies were observed during 16 years in the Bydgoszcz region and during 19 years in the Wroclaw region. A higher rainfall deficit during the 20-year period under study was reported in the Wroclaw region (128.5 mm) than in the Bydgoszcz region (87.0 mm). In August, the highest monthly precipitation deficiencies of 100.3 mm (Wroclaw region) and 70.3 mm (Bydgoszcz region) were noted

The efficiency of drip fertigation in cultivation of winter squash „Gomez” on the very light soil

The study of drip fertigation of winter squash ‘Gomez’ was conducted on the very light soil on the experimental field in Kruszyn Krajeński near Bydgoszcz in the years 2007 and 2008. The research was established as one-factorial, using the method of drawn blocks, in four replications. Drip fertigation (DF) as the liquid fertilization supplied nitrogen, potassium and phosphorus to the plants three times during growing season. As the control (DP), the drip irrigation combined with broadcast application was used. The potassium and phosphorus fertilization of control plots was applied before seed sawing. The nitrogen fertilization of control plots was provided in three single doses during vegetation. The liquid and powder fertilizations were performed at the same time. The complex fertilizer ‚Universol Blue’ (N:P:K = 18:11:18) was used. The dose of fertilizer was 3:2:3 (187.5:125:187.5 kg of NPK per ha). The irrigation was conducted using the drip line ‚T-Tape’. The liquid fertilizer was mixed by the ‚Dosatron’ dispenser. The irrigation started when the soil water pressure, measured with the tensiometers, was near - 0.04 MPa. In comparison to the control (powder fertilization), the drip fertigation (liquid fertilization) significantly increased marketable fruit yield, single fruit weight and fruit number. Most of the tested chemical components of ‘Gomez’ fruits (vitamin C, total sugar, monosaccharides, saccharose, total carotenoids and ß-carotin) were not significantly influenced by drip fertigation. However, the level of dry weight of winter squash ‘Gomez’ fruits was reduced by drip fertigation

Influence of drip irrigation on nutritive value of winter squash „Rouge vif d’Etampes” after harvest and storage

The aim of the study was to determine the influence of drip irrigation on the nutritive value of winter squash ‘Rouge vif d’Etampes’ fruits analyzed directly after the harvest and after the storage. The plants were grown on the very light soil in the region of decreased rainfall amounts during the vegetation period. The field experiment was conducted in 2007-2008 at Kruszyn Krajeński near Bydgoszcz on the soil of quality class V-VI (very weak and weak-rye-soil-complex). The field water capacity in the soil layer 0-50 cm was 57.5 mm, while the effective useful retention amounted 29.3 mm. The experiment was designed as one-factorial trial in four replications; drip irrigation as the experiment factor was applied. As the control the plots without irrigation were considered. The single plot area was 11.2 m2. The drip irrigation was conducted according to the soil tensiometer indications (-0.04 MPa). The research material was the eatable parts of fresh fruits that were analyzed directly after the harvest and after the storage for six months at the temperature 10°C and the relative air humidity 75%. The drip irrigation performed during the cultivation of winter squash increased the content of vitamin C, total carotenoids including ß-carotene, as well sugars in the fruits, both after the harvest and after the storage. After six months of the storage the rise of the content of dry matter, total carotenoids including ß-carotene, as well monosaccharides was noted, while the level of vitamin C, total sugar, and saccharose have been reduced

Influence of drip irrigation on the yielding of summer squash „White Bush” under rainfall-thermal conditions of Bydgoszcz and Stargard

The aim of the study was to determine the effect of drip irrigation on yielding of summer squash ‘White Bush’ grown under conditions of two localities: Lipnik near Stargard Szczeciński (soil of quality class IVb, and of good-rye-soil-complex) and Kruszyn Krajeński near Bydgoszcz (soil of quality class V, and of weak-rye-soil-complex). The study was designed as one-factorial trial: drip irrigation as the experimental factor was considered. Drip irrigation was conducted according to soil tensiometer indications (-0.04 MPa). Both, in Lipnik as well as in Kruszyn Krajeński, drip irrigation significantly increased marketable yield of summer squash ‘White Bush’. A higher rise in yields due to irrigation was obtained in Kruszyn Krajeński than in Lipnik. Mean marketable yield of summer squash fruits in Lipnik was higher than that obtained in Kruszyn Krajeński. Drip irrigation significantly increased the single fruit weight in relation to the control, in both crop localities. The system of drip irrigation significantly affected the number of fruits per plant. Summer squash plants grown in Lipnik produced higher number of fruits, than in Kruszyn Krajeński. In addition, essential influence of drip irrigation was affirmed on chemical composition of fruits, i.e. dry matter, vitamin C, monosaccharides, saccharose, content of total sugars and sum of carotenoids and ß-carotin