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Acta Ornithologica
|
1999
|
tom 34
|
nr 2
219-226
In 1991-1995 fourteen morphological traits of Great Tits breeding in nest boxes were measured. Their relation to fitness was checked in elements of a tifs biology: survival of young to first reproduction, competition for nesting places, first and second broods, lifetime survival and reproduction. Selection intensity (i) was calculated for principal components of body size. Phenotypic selection evidences were mainly singular. Comparison of body size of individuals recruited to the studied population revealed that males of larger body size were recruited to the population. An experiment showed that individuals with larger bills won competition for nest boxes (i for bill length ranged from 0.05 in males to 0.34 in females). Clutch size depended positively on the measurements of males (i = 0.07 and i = 0.11 respectively), and negatively on the body measurements of females during the first brood (i = -0.08 in 1995). During the second broods there was a positive trend in relation between body size of parents and young condition (for females i = 0.05 and i = 0.02 respectively, for males i = 0.08 in 1992). Intensive selection on body size (i = -0.34 for males, i = -0.61 for females), due to a catastrophic impact of bad weather was recorded as well. Analysis of lifetime data on the longevity and mean breeding success per year, revealed for 1991 cohort of individuals a strong negative selection on body size in females (i = -0.46 with regard to breeding success, i = -0.16, longevity) and positive selection on forearm length in males in 1993 (i = -0.128, longevity). For 8 cases of selection, its direction in males favoured larger body size (7 cases), whereas in females selection directions were differentiated (3 positive, 3 negative). This pattern was concordant with sexual size dimorphism in the studied population.
A three-factor field experiment on linseed was conducted in 2000-2003. The effect of studied factors on assimilation area, seed yield and yield composition was assessed. The value of canopy leaf area index and green assimilation area index at the linseed flowering phase were most diversified by the seed sowing rate. Yielding of linseed Opal cv. (Polish brown seeded variety) and Hungarian, Hungarian Gold cv. with yellow seeds was very similar. The linseed sowing rate influenced the amount of seed yield and its components. A dose of mineral ferti­lizer raised from 90 to 180 kg NPK/ha increased the seed yield which grew from 1.77 to 1.88 t ha-1, i.e. by 6.2%.
The amount and structure of yields of spring barley Edgar cv. and field bean Nadwiślański cv. cultivated as cover crops for under sown red clover, Nike cv. were investigated in 1993-1995 at an experimental plot of Department of Plant Production situated in Prusy near Cracow. Both cover crops were sown at the following distances between rows: 11, 22, 11 + 33 and 33 cm. Broad drilling (33) and stripe drilling (11 + 33 cm) decreased leave area index in both species and enabled a far better access of photosynthetic active radiation to the undersown red clover. A significant decline in spring barley yield in broad drilling was due to a decrease in the number of ears per area unit. However, as compared to the narrow drilling (11 cm), the fall was 21%. Field bean responded to increased row spacing by a lower decline in seed yield because a decrease in the number of plants per m² was counterbalanced by an increase in the following values: 1000 grain weight, number of pods per plant and number of seeds per pod. Red clover undersown in field bean developed better, which has been proved by both the number of plants per m² and the number of developed side shoots.
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Znaczenie nawozowe miedzyplonow w uprawie pszenicy

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Rośliny w warunkach górskich, niezależnie od sposobu siewu, cechowało zmienne w latach plonowanie. Najwyższe plony dały tetraploidalna koniczyna, tymotka i ich mieszanka, a najniższe komonica. Szybciej z runi ustępowały koniczyny, zwłaszcza diploidalna, wolniej komonica. Sposób siewu nic różnicował w istotny sposób plonu białka, pomimo znacznych różnic w jego zawartości. Wyższą efektywnością charakteryzowała się technologia konno-ciągnikowa, zwłaszcza w odniesieniu do uprawy roślin motylkowatych w siewie czystym, w II i III roku użytkowania.
W teorii ekologii istnieje kilka bardzo ważnych modeli opisujących zasady osiedlania się organizmów. Poniżej przedstawiono najważniejsze z nich wskazując na występujący we wszystkich wspólny element: lepsze siedliska są zawsze zajmowane przez osobniki wcześniej niż siedliska gorsze. Wskazuje to na prosty mechanizm oceny jakości siedlisk – powinny one być oceniane na podstawie kolejności zasiedlania
Plant samples al the and of I-st cutting were collected from field experiment or from teaching collection in order to determine the degree of relationship of in pairs of traits. The degree of the relationship between investigated was estimated by linear or curvilinear regresion and only equation for which coeficient of determination R2 was greated than 0.5 were reported in the paper. Leave surface area from steams of compared species of papilionaceous depended to small degree on ite shave of small leaves in this feature (<1/4.). The magnitude of the total leave surface area depended on large, and mainly average leaves. Increasing number of leaves on the steam had a positive effect on total leave surface area, and moderate linear relation between features was observed (R3=O.70). The order of species according to their decreasing number of leaves on the steam is following: alfalfa-33.4 > bird's fool trefoil-15.2 > red clover-7.9 > sainfoin-5.1). Between the mass of the steam of single species and its length curvilinear relation was observed, which informs about above average influence of longer steams (>70 cm) on yield. Plant mass was poorly correlated with the total steam length. Among single plants (small, average, large) significant differences were observed in the mass of single steams. Share of separated groups of steams in the mass of tops varied greatly and was following: 25% of largest steams decided about the half of its yield. In turn 50% of steams (small and very small) formed only 25% of top yield.
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