Effect of Temperature on the Yield and Quality of Broccoli Heads
The effect of temperature on the yield and quality of broccoli heads was determined. The study involved three cultivars: Cruiser, Skiff and Fiesta. The seedlings were planted on five different dates in 1995 and 1996, nine in 1997 and eight in 1998. The length of time from planting to the first harvest for all the 27 cultivation periods was divided into three equal parts determining in this way three phases of growth. The time of harvest was defined as the fourth phase. Temperatures on a scale from 0°C to 40°C were divided into five-degree ranges. Then, for the four growth phases, correlations were determined between the number of hours at a temperature in the five-degree ranges and the total yield, the percentage of loose heads and the percentages of heads with uneven surface or non-uniform buds.
The length of time at a temperature in the range of 15-25°C during the first growth phase after planting and the phase preceding harvest had the greatest influence on total yield. Longer times at temperatures above 20°C contributed to smaller yields. The longer was the length of time at a temperature ranging from 20 to 25°C during the phase preceding harvest and at a temperature ranging from 5 to 15°C during harvest, the lower the percentage of heads with uneven surface was observed. Longer periods with temperatures above 20°C at harvest time contributed to the loosening of heads.
The white button mushroom Agaricus bisporus (Lange) Imbach is an edible mushroom of top economic significance. In recent years the consumption of fruiting bodies of this species has been increasing in Poland. The article characterises the chemical composition and health-promoting properties of white button mushrooms. The latest scientific research confirms that the fruiting bodies of white button mushroom have high nutritional value. They contain good quality proteins, necessary unsaturated fatty acids, fibre, some vitamins and numerous minerals. Apart from that, white button mushroom fruiting bodies contain a wide range of bioactive substances, which have a positive influence on health, such as polysaccharides, glyco-proteins, tocopherols, polyphenols and other antioxidants, e.g. ergothioneine. Apart from the antioxidant properties, the white button mushroom also has anti-inflammatory, antimicrobial, antifungal, anticancer, immunomodulatory, hepatoprotective and anti-atherosclerotic activities.
There are about 40 species in the Pleurotus genus, including those with high economic significance, i.e. P. ostreatus and P. pulmonarius. The fruiting bodies of oyster mushrooms are of high nutritional and health-promoting value. In addition, many species belonging to the Pleurotus genus have been used as sources of substances with documented medicinal properties, such as high-molecular weight bioactive compounds (polysaccharides, peptides and proteins) and low-molecular weight compounds (terpenoids, fatty acid esters and polyphenols). The bioactive substances contained in the mycelium and fruiting bodies of Pleurotus species exhibit immunostimulatory, anti-neoplastic, anti-diabetic, anti-atherosclerotic, anti-inflammatory, antibacterial and anti-oxidative properties. Their multidirectional positive influence on the human organism is the result of interaction of bioactive substances. Extracts from individual Pleurotus species can be used for the production of dietary supplements increasing the organism’s immunity. They are also used for the production of cosmetics. They can be added to functional foods as probiotics, or used as natural preservatives or ingredients of special foodstuffs for patients with specific diseases.
Biostimulants are commonly used in horticulture, primarily to increase yield quantity and quality, as well as plant tolerance to stress. The purpose of the study was to determine the effect of amino acid-based biostimulants and amino acids in combination with Ascophyllum nodosum filtrate, applied during the growing season on the phenolic content in broccoli heads both after harvest and after long storage in a cold store. The seedlings were planted in mid-July, and heads were harvested from September to October in each year of the study. Ascophyllum nodosum filtrate at a concentration of 1% was used during seedling production. The plants were watered with biostimulants twice, in the fourth and fifth week after sowing. They were also sprayed with amino acid-based biostimulants (1.5 dm3 ha-1) three times, i.e. after the second, fourth and sixth week after planting. The biostimulants were not used in the control treatment. After harvest, the heads were stored for three weeks in a cold store at 1-2°C and 95% RH. Chemical analyses of total phenolic, caffeic, ferulic and sinapic acids, and of quercetin and kaempferol were carried out on samples of fresh broccoli and after the first, second and third week of storage. It was found that the application of biostimulants resulted in a significant increase in the total phenolic content, sinapic acid content, as well as quercetin content. Both in the control treatment and in the plants treated with the biostimulants, the concentration of all the tested phenolic compounds increased with the duration of storage.
Green spear yield of 16 asparagus cultivars originating from six countries was assessed from 2011 to 2013. There were considerable differences in total, marketable and early yields between the cultivars. The quality of harvested spears also varied remarkably. On average, the highest mean total and marketable yields from 3 years of investigation came from Dutch cultivars ‘Gijnlim’ and ‘Cumulus’ and German cv. ‘Mondeo’. The lowest yields were found in New Zealand cultivars ‘Pacific Challenger’ and ‘Pacific 2000’. The greatest mean marketable spear weight was recorded for ‘Cumulus’, whereas the smallest spear weight was obtained from ‘Pacific 2000’, ‘H666’ and ‘NJ 953’. Cultivars ‘Gijnlim’, ‘Cumulus’ and ‘Mondeo’ produced the highest early yields, while ‘Pacific 2000’ and ‘Pacific Challenger’ produced the lowest.
In order to determine the dependence between summer stalks size of tested cultivars in the preceding year and their yields in the following year, regression equations and their correlation coefficients were estimated. The size of summer stalks was expressed as plant growth index, which was the multiplication of height and total cross-sectional area of summer stalks. There was a significant and positive correlation between plant growth index of tested cultivars and their yields in the next vegetation period. The correlation coefficients between these two parameters amounted to 0.62 and 0.68 in 2011/2012 and 2012/2013, respectively
The aim of the research was to assess the influence of calcium chloride and calcium lactate irrigation on the yield volume and dry matter content in two champignon strains, ie Amycel 2200 and Italspawn F59. When both strains were irrigated with calcium lactate, there was a significant decrease observed in the yield when the concentration of the solution was 0.6%. On the other hand, when calcium chloride was applied to the Italspawn F59 strain, there was a significant decrease in the yield when the concentration was as low as 0.4%, whereas the yield of the Amycel 2200 strain dropped when the concentration of calcium chloride was 0.6%. The irrigation with calcium chloride and calcium lactate had influence on the content of dry matter in the champignon carpophores. When the solutions under investigation were applied at concentrations of 0.4 and 0.6%, there was a significant increase observed in the content of dry matter in both strains.
Three-year studies on the influence of temperature on vegetative growth and growth of broccoli heads (Brassica oleracea var. italica cv. Fiesta) were carried out at the Experimental Station “Marcelin” of Poznań University of Life Sciences in Poland. The relationship between temperature sum day-degree, number and area of leaves as well as head diameter was estimated. Likewise relationship between number and area of leaves and head diameter was established. The correlations were described using linear, curvilinear and segment linear regression. The relationship between temperature sum day-degree and number of leaves was linear, whereas the correlation between temperature and area of leaves and head diameter was curves function. On the basis of segment linear regression it was found that in the period when slow growth of heads was observed (the size of up to about 1.5 cm), the area of leaves increased the fastest. It occurred between the 24th and 27th day after planting. The fastest growth of broccoli heads was noted, when the plant had about 18 leaves and area 4900 cm2. In the period of rapid head growth, the increase of sum temperature of 100 day-degree resulted in head diameter increase by 3.5 cm.
Variability of Economic Traits of 28 Cultivars of Asparagus (Asparagus officinalis L.)
The research which aim was to characterise variability of economic traits of 28 asparagus cultivars was carried out in the Marcelin Experiment Station in the years 2004-2008. Variability of total and marketable yields, the mean weight of green spears as well as plant survival of all the 28 cultivars and separately of nine German and Dutch cultivars was evaluated. In addition, variability between harvest years of individual cultivars for total and marketable yields, mean spear weight in five and spear thickness in three selected harvest years was characterised.
Variability between cultivars was found greater with respect to marketable and total yields expressed in the weight of harvested spears and smaller with respect to mean spear weight and total yield expressed in the number of harvested spears. Less productive cultivars exhibited the least consistent yields between individual harvest years and the worst plant survival. Higher yield consistency, mean spear weight and plant survival were observed in the group of German and Dutch cultivars.