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A pot experiment on different methods of EM 1 application was conducted in the period 2002–2004. The study was carried out under controlled growth conditions. The experimental factor was the method of EM1 application. Before application, the biological preparation EM1 was propagated as recommended by the manufacturer (Greenland). The health status of the aboveground parts of ‘Ramrod’ pea plants was estimated at the flowering stage. The assessment of pea leaf gas exchange parameters (An, E, Gs, and Ci) was made using a LI-Cor 6400 Portable Photosynthesis System. Soil application of EM1 combined with chemical control contributed to inhibiting Fusarium wilt of pea. Foliar application of EM1 combined with chemical control increased all gas exchange rates of pea leaves. Fusarium wilt of pea insignificantly decreased all gas exchange rates of pea leaves and the number of seeds per pod. The best method of EM1 application was soil treatment combined with chemical control, which increased all yield-related morphometric parameters of pea.
The present pot experiment studied the effect of different soil moisture contents (60 – 70% CWC (capillary water capacity) – control; 30 – 35% CWC – water stress) on buckwheat productivity, the gas exchange parameters and health of buckwheat nuts. It was found that water deficit affected adversely certain biometric features investigated (plant height, number of nuts per cluster) and caused a decrease in seed weight per plant. It was also shown that water stress reduced the values of the investigated gas exchange parameters (photosynthesis rate, transpiration rate, intercellular-space CO2 concentration, and stomatal conductance) relative to the control treatment. Different soil moisture contents did not have a clear effect on fungal colonization of seeds. The multiplex PCR assays did not enable the detection of the genes responsible for mycotoxin synthesis. Under water deficit conditions, an increase was found in the content of albumin and globulin fractions as well as of glutelin fractions.
A research experiment was conducted in which rates of photosynthesis and transpiration were measured in leaves and ears of two winter wheat varieties grown under fungicide control conditions and without fungicide control. A LI-COR 6400 portable gas exchange system was used in the investigations. In most cases the fungicide Juwel was shown to have no effect on the gas exchange processes, whereas the other of the fungicidal agents applied – Swing – significantly decreased the gas exchange rates measured. Measurements of gas exchange parameters in ears showed that the intensity of gas exchange was low, in particular at the later stage of ear development. But the applied fungicide caused higher release of CO2 into the atmosphere than its uptake. Furthermore, the applied fungicides were found to significantly increase grain yield compared to the control treatment, both in the first and second year of the study. Among the tested varieties, ‘Nutka’ was characterized by higher productivity, in spite of lower 1000 kernel weight. However, this cultivar developed longer ears with a larger amount of grains.
Copper is essential for the growth and development of plants. This micronutrient affects chlorophyll content, photosynthesis process and water relations in the plant. The objective of this study was to determine the effect of copper deficiency in soil on the rate of photosynthesis and transpiration, water use efficiency, leaf greenness and the yield of selected cultivars of perennial ryegrass (Lolium perenne L.) and orchard grass (Dactylis glomerata L.). During the growing season, the rate of photosynthesis and transpiration was measured using a LI-COR 6400 gas analyzer (Portable Photosynthesis System), and leaf greenness was estimated with a Minolta SPAD-502 chlorophyll meter. Water use efficiency (WUE) was calculated based on instantaneous values of photosynthesis and transpiration. Dry matter yield was determined by green matter drying to constant weight at 105oC. The results of the study indicate that copper deficiency significantly decreased the rate of photosynthesis and transpiration, chlorophyll concentration in leaves and the yield of all investigated cultivars. Perennial ryegrass cv. Maja was found to be most resistant to copper deficiency – it was characterized by a high rate of photosynthesis and transpiration, and by the highest chlorophyll content. The yield of cv. Maja attained under copper deficit conditions was comparable to that of other cultivars grown under control conditions.
The rate of photosynthesis and transpiration, intercellular CO₂ concentration and stomatal conductance in spring wheat plants were determined in an experiment conducted during the years 2004–2005. The severity of fungal infection of wheat kernels was estimated by a traditional method and a molecular BIO-PCR technique with the use of universal and SCAR primers. It was found that water deficit decreased thousand grain weight, grain weight per plant and the values of gas exchange parameters (including photosynthesis, transpiration, stomatal conductance, intercellular CO₂ concentration), in particular photosynthesis. The values of biometric characters did not decrease. The rate of wheat grain colonization by fungal pathogens was slightly higher under water stress conditions.
The objective of this study was to determine the effect of manganese deficiency in soil on the rate of photosynthesis and transpiration, water use efficiency, leaf greenness and the yield of selected cultivars of perennial ryegrass (Lolium perenne L.) and orchard grass (Dactylis glomerata L.). During the growing season, the rate of photosynthesis and transpiration was measured using a LI-COR 6400 gas analyzer (Portable Photosynthesis System), and leaf greenness was estimated with a Minolta SPAD-502 chlorophyll meter. Water use efficiency (WUE) was calculated based on instantaneous values of photosynthesis and transpiration. Dry matter yield was determined by green matter drying to constant weight at 105oC. The results of the study indicate that the response of grasses to manganese deficiency in soil was dependent on plant species and cultivar. In the present experiment perennial ryegrass cultivars showed a stronger response to manganese deficit than orchard grass cultivars. Their response involved a decrease in the rate of photosynthesis and transpiration, and in the chlorophyll content of leaves. Among the tested cultivars, perennial ryegrass cv. Maja was found to be most sensitive to manganese deficiency in soil, as confirmed by the highest decrease in the values of all examined parameters.
Phosphorus is essential for the growth and development of plants. It also determines the quantity and quality of plant yields. Phosphorus actively participates in many vital processes and forms part of numerous substances indispensable for a normal course of certain biochemical changes. Unfortunately, phosphorus deficiency is quite common in grasslands. As a result, the content of phosphorus in soil is insufficient to meet nutritional requirements of forage crops and, consequently, the concentration of this element in green forage is insufficient to meet nutritional requirements of ruminants. The aim of the present study was to determine the effect of phosphorus deficiency in soil on the rate of photosynthesis and transpiration, water use efficiency, leaf greenness and the yield of some cultivars of perennial ryegrass (Lolium perenne L.) and orchard grass (Dactylis glomerata L.). A greenhouse experiment was conducted to assess the rate of photosynthesis and transpiration, water use efficiency (WUE), leaf greenness (SPAD - Soil-Plant Analysis Development) and the yield of perennial ryegrass (Lolium perenne L.) and orchard grass (Dactylis glomerata L.) grown under conditions of phosphorus deficiency in soil. The rate of photosynthesis and transpiration was measured using a LiCor 6400 gas analyzer (Portable Photosynthesis System), and leaf greenness was estimated with a Minolta SPAD-502 chlorophyll meter. Dry matter yield was determined by drying green matter to constant weight at 105 st.C. The results of the study indicate that phosphorus deficiency significantly decreased the rate of photosynthesis, water use efficiency and the yield of perennial ryegrass and orchard grass. At the same time, it increased the rate of transpiration and leaf greenness values. Among the tested cultivars, orchard grass cv. Areda was found to be the most resistant to phosphorus deficiency in soil, which was confirmed by the slightest reduction in the examined parameters.
Celem badań przeprowadzonych w latach 2010-2012 na jednorocznych, dwu- i trzyletnich pędach trzech odmian Salix viminalis: Bjor, Jorr i Tora, wyrosłych z 14. 15. i 16 letnich karp, było porównanie ich pod względem aktywności procesów asymilacji i transpiracji, a także parmetrów wpływających na te procesy, tj. przewodności szaprkowej, stężenia podszparkowego CO2, fotosyntetycznego współczynnika wykorzystania wody (WUE) i chwilowego fotosyntetycznego współczynnika wykorzystania wody (WUEI) oraz pod względem plonowania. Pomiary wymiany gazowej wykonano za pomocą analizatora gazu typu TPS-2 z kamerą PLC-4 (PP System, USA), pracującego w układzie otwartym. Na podstawie uzyskanych wyników stwierdzono, że pędy jednoroczne odmiany Jorr wykazały się najkorzystniejszymi parametrami wymiany gazowej, zaś najsłabszymi trzyletnie pędy odmiany Tora. Wysoka ogólna aktywność procesów wymiany gazowej u odmiany Jorr pozwoliła mu osiągnąć największy plon biomasy pędów, niezależnie od cyklu zbio-ru. Mimo zaawansowanego wieku plantacji (14-16 rok uprawy) badane odmiany wykazały się dużą produktywnością biomasy. Prawdopodobnie, ze względu na duży przyrost masy drzewnej trzylet-nich pędów u odmiany Bjor, stanowiący ok. 58% całego trzyletniego przyrostu, znacząco większy niż u Jorr i Tora (ok. 50%), najkorzystniejszy dla tej odmiany byłby zbiór co 4 lata.
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