Piotr Siwek

The effect of biodegradable nonwoven direct covers on yield and quality of winter leek

ABSTRACT During this two-year experiment (2008-2010), the ‘Kenton’ leek cultivar was grown in the field from July to March/April of the following year. During the winter months the plants were kept under biodegradable nonwoven covers (Bionolle - polybutylene succinate, 59 and 100 g m-2). The control treatments were left uncovered. Some cracks and tears in the biodegradable nonwoven covers were observed. The covers resulted in better leek yields. In the first season the bleached parts of the leek contained more ascorbic acid when kept under the Bionolle 100 g m-2 cover. The lighter nonwoven (59 g m-2) cover caused a grater accumulation of soluble sugars. Biodegradable films, used in the winter cultivation of leek, increased the soil temperature by 1°C on average.

The effect of biodegradable nonwovens in butterhead lettuce cultivation for early harvest

Abstract Field experiments using ‘melt-blown’ biodegradable nonwovens were carried out on the ‘Melodion’ butterhead lettuce (Lactuca sativa var. capitata L.) cultivar for early harvest. All biodegradable nonwovens were manufactured in the Institute of Biopolymers and Chemical Fibres and POLMATEX CENARO in Łódź, Poland. Lettuce seeds were sown into boxes in a greenhouse at the beginning of March, and transplants were planted into the field at the beginning of April. Biodegradable nonwovens - aromatic polyester IBWCH 75 g m-2, polybutylene succinate Bionolle 100 g m-2 and standard polypropylene PP Agro 20 g m-2 - were stretched over the lettuce in the field. The covers were kept on until 4-5 days before harvest. Plots without covers were defined as the control. Ascorbic acid, soluble sugar, dry matter, nitrates, chlorophyll a, chlorophyll b and carotenoid contents were recorded in the leaves. All biodegradable nonwovens showed a positive effect on yielding in comparison to the control in 2009. In the second year of the experiment, there were no significant differences between covers with regard to the yield. Dry matter and soluble sugar content in both years of the experiment was diversified. Nonwovens used as covers in 2009 significantly increased the content of nitrates in comparison to the control. In the second year, the highest level of nitrates was demonstrated in the control object. It is worth underlining that the maximum allowed limit of nitrate content in lettuce (4000 mg kg f.w.) was not exceed. The kind of cover had no significant effect on the level of chlorophyll a in 2009 or chlorophyll b and carotenoids in 2009 and 2010 in the lettuce

The effects of PLA biodegradable and polypropylene nonwoven crop mulches on selected components of tomato grown in the field

ABSTRACT The results of two years (2010-2011) of field studies using two types of nonwoven mulches (one biodegradable, polylactic acid PLA 54 g m-2, and traditional polypropylene PP 50 g m-2) on the yield and quality of tomato are presented. Seeds of tomato (‘Mundi’ F1) were sown in a greenhouse, in containers filled with perlite and sand, and then the plants at the cotyledon stage were replanted in multipot trays filled with substrate for vegetable plants. In the last week of May, seedlings were planted on mulches in the field at a spacing of 50 × 100 cm. The mulch was maintained throughout the growing season. A plot that remained unmulched served as the control. Tomatoes were harvested once a week. The fruits were evaluated for L-ascorbic acid, dry matter, soluble sugars and nitrate content. In 2011, the analysis of the plant material showed that the concentration of L-ascorbic acid was about 23% higher in the tomato fruits harvested from plants grown on biodegradable PLA 61 g m-2 mulch in comparison to the control. A similar effect was demonstrated for the soluble sugar concentration in 2011 for both types of nonwovens.

The effect of biodegradable direct covers on the root development, yield and quality of cucumber

ABSTRACT The results of three years (2009-2011) of field studies using two types of biodegradable nonwoven covers (aromatic polyester IBWCH 75 g m-2 and polylactic acid PLA 54 g m-2) on the yield, quality and root development of cucumber are presented. Seeds of parthenocarpic cucumber (‘Mirabelle’ F1) were sown directly into the field at the beginning of May/June and covered with nonwoven field covers. A plot that remained uncovered served as the control. The covers were kept in place until the first flowers appeared. Cucumbers were harvested every three days for 5-6 weeks. Fruits were evaluated for dry matter, soluble sugars and nitrate content. After the last harvest, whole plants were harvested and evaluated for weight, surface area, total length and average diameter of the roots. The experiment showed that the covers increased the marketable yield of cucumber in 2009 and 2010 (regardless of the type of polymer), but did not influence the yield in 2011. In 2011 the fruits from the covered plots had higher levels of soluble sugars and dry matter in comparison to the control. The covers did not influence root development. Streszczenie Przedstawiono wyniki trzyletnich (2009-2011) badań z wykorzystaniem do bezpośredniego osłaniania roślin ogórka dwóch włóknin biodegradowalnych (IBWCH 75 g m-2 i P LA 5 4 g m-2). Nasiona ogórka partenokarpicznego ‘Mirabelle’ F1 wysiano bezpośrednio do gruntu na początku maja/czerwca i jednocześnie przykryto włókninami biodegradowalnymi. Jako kontrolę przyjęto rośliny nieosłonięte. Osłony utrzymywano do momentu pojawienia się pierwszych kwiatów. Owoce ogórka zbierano co 3 dni przez okres 5-6 tygodni. W laboratorium w owocach oznaczano zawartość suchej masy, cukrów rozpuszczalnych oraz jonów azotanowych. Po wykonaniu ostatniego zbioru owoców wykopano całe roślin ogórka z gleby - wraz z systemem korzeniowym, który następnie został poddany analizom pod względem: masy, całkowitej powierzchni, całkowitej długości oraz przeciętnej średnicy rozgałęzienia. Doświadczenia wykazały, że zastosowanie osłon (niezależnie od rodzaju polimeru, z którego zostały wykonane) spowodowało wzrost wielkości plonu handlowego owoców ogórka w 2009 i 2010 roku, nie wykazano takiego w pływu w ostatnim roku doświadczeń (2011). W 2011 roku owoce ogórka zebrane z obiektów osłoniętych wykazały większą zawartość cukrów rozpuszczalnych, suchej masy w porównaniu z kontrolą. Zastosowanie osłon nie wpłynęło na oceniane parametry rozwoju systemu korzeniowego.

The Effect of Different Kind of Polyethylene Film Used as a Low Tunnel Cover on Celery Yield and Stalk Quality

The Effect of Different Kind of Polyethylene Film Used as a Low Tunnel Cover on Celery Yield and Stalk Quality Earlier experiments showed that celery could be grown under different plastic covers for spring and autumn harvest. The most significant for yield quantity and quality were light conditions. In conducted studies (2005-2007) the effect of three different covers for low tunnels: transparent, white and black film (made of original and recycled polyethylene) on the growth, yield and some quality factors of celery Tango stalks was estimated. Only small differences in the length of celery stalks grown under different films were observed. In the third year of experiment stalks grown under black film were around 1cm longer than all the others. Mean values of the yield indicate that transparent film used as a cover and the control treatment increased slightly the obtained yield but the differences did not exceed several percent. Plants grown in more favourable light conditions accumulated more dry matter as well as more soluble sugars in celery stalks. No such differences were observed under original and recycled films. Plon Selerów Naciowych i ich Jakość W Tunelach Pokrytych Różnymi Rodzajami Folii Polietylenowej Wcześniejsze eksperymenty wykazały, że seler naciowy może być z powodzeniem uprawiany na zbiór wiosenny i jesienny pod osłonami wykonanymi z różnych folii, a czynnikiem w największym stopniu modyfikującym wielkość i jakość plonu były warunki świetlne. W trzyletnich doświadczeniach oceniano wpływ bezbarwnej, białej i czarnej folii pelietylenowej wykonanej z surowców oryginalnych i recyklingowych na tunelach niskich na wzrost, plon i wybrane parametry jakości ogonków liściowych selerów naciowych odmiany Tango. Pomiędzy poszczególnymi rodzajami folii nie stwierdzono różnic we wzroście elongacyjnym roślin. Jedynie pod folią czarna długość ogonków była o 1 cm większa niż w pozostałych obiektach. Plon ogonków liściowych był o kilka procent większy w przypadku stosowania folii bezbarwnej i w obiekcie kontrolnym. W lepszych warunkach świetlnych rośliny akumulowały więcej suchej masy i cukrów rozpuszczalnych. Stwierdzono, że większy wpływ na rośliny wykazała ilość promieniowania przepuszczanego przez folie niż jego skład spektralny. Nie obserwowano różnic pod wpływem folii oryginalnej i recyklingowej.

Influence of the homehold composting conditions on the structural changes of polylactide spun-bonded nonwovens during degradation

In this study, the influence of homehold composting conditions on the molecular and supramolecular structure of polylactide (PLA) in the form of spun-bonded nonwovens was investigated. Nonwoven samples were studied using size-exclusion chromatography coupled with multiangle laser light scattering detection, wide-angle X-ray diffraction, differential scanning calorimetry and Fourier transform infrared spectroscopy. In addition, the physical and mechanical properties of the nonwovens before and after composting were determined. The results show the varying degree of influence of the prepared compost mixtures of soil with common horticultural additives, such as chalk, commercially available agents, cow manure and chicken litter, on the molecular and supramolecular structure of PLA and its degradation rate. The obtained experiment explained which popular homehold agent had the strongest affect on the PLA nonwoven dedicated for agriculture use in the first period of season composting (first 6 months).

The influence of biodegradable mulches on the yielding of autumn raspberry (Rubus idaeus L.)

Abstract A three-year experiment was set up to assess the effect of three mulch types on the growth and yield of ‘Polka’ autumn fruiting raspberry (Rubus idaeus L.). The experimental arrangement comprised four combinations of two parallel blocks, one of which was a field crop and the second was a covered crop in the form of a high tunnel with raised beds sides. The crop was grown on raised beds (approximately 30 cm high) covered with a mulch made of: 1) polypropylene non-woven (PP); 2) PP with a photodegradant; 3) polylactide nonwoven (PLA). A crop on a raised bed without any mulch was the control. Biometric, physiological and yield parameters were assessed and included the number of canes, plant height, chlorophyll content in the leaves, fruit yield, weight of 20 fruits and the extract content. The obtained results show that the height of the canes grown on PLA and PP mulch was significantly higher than for the PP with photodegradant. Cultivation on PP, PLA and PP with photodegradant mulch resulted in a significant increase in the weight of 20 raspberry fruits and higher chlorophyll content in the leaves compared to the control combination.

Effects of plastic mulches and high tunnel raspberry production systems on soil physicochemical quality indicators

Abstract In horticulture, degradable materials are desirable alternatives to plastic films. Our aim was to study the impact of soil plastic mulching on the soil properties in the high tunnel and open field production systems of raspberry. The raised beds were mulched with a polypropylene non-woven and two degradable mulches: polypropylene with a photodegradant and non-woven polylactide. The results indicated that the system of raspberry production, as well as the type of mulching had significant impact on soil organic carbon stock, moisture content and water stable aggregate amount. Soils taken from the open field system had a lower bulk density and water stability aggregation index, but higher organic carbon and capillary water content as compared to soils collected from high tunnel conditions. In comparison with the open field system, soil salinity was also found to be higher in high tunnel, as well as with higher P, Mg, Ca, S, Na and B content. Furthermore, mulch covered soils had more organic carbon amount than the bare soils. Soil mulching also enhanced the water capacity expressed as a volume of capillary water content. In addition, mulching improved the soil structure in relation to the bare soil, in particular, in open field conditions. The impact of the compared mulches on soil quality indicators was similar.

Effect of Agri-Environmental Conditions on the Degradation of Spunbonded Polypropylene Nonwoven with a Photoactivator in Mulched Organically Managed Zucchini

An experiment with non-degradable and degradable soil mulching materials in zucchini cultivation was carried out in 2016 and 2017 in the organic field of the Vegetable Experimental Station, Agricultural University of Kraków. Two kinds of polypropylene (PP) nonwoven of 50 g m-2 were used: PP standard and PP with 0.1% photoactivator. The control treatment were plots without mulching. The marketable yield obtained in 2016 was 21% and 15% higher on the plots mulched with PP nonwoven and PP nonwoven with a photoactivator, respectively, in comparison with the non-covered plots. Mulching the soil with PP nonwoven increased the water resistance index of the soil structure in comparison with the control and photodegradable PP nonwoven mulch. The progress of degradation over a two-month period showed a 40% reduction in the mass of the PP nonwoven with a photoactivator, and at the end of vegetation the mass of the PP nonwoven used was 52% lower than that of a new one. Tensile parameters of the PP nonwovens and their supramolecular structure were measured.