Micronutrient, magnesium and phosphorus effects on biomass and leaf tissue nutrient concentrations of field grown Leucaena leucocephala

To optimize biomass and crude protein (CP) production for leucaena (Leucaena leucocephala) in southern Texas, field trials were conducted with treatment combinations of three levels of phosphorus (P) , two levels of Mg and two levels of soluble trace element mixture (STEM). The P was banded in the soil while the Mg and micronutrient blend were applied to the foliage. A combination of P (22 kg ha^-1), Mg and STEM fertilizers significantly increased biomass from 2555 kg ha^-1 to 3028 kg ha^-1. This treatment was associated with an increase in leaf CP from 27.9% to 31.0%. P fertilizer had no significant effect on leaf P, but significantly increased leaf nitrogen (N) and leaf copper (Cu). A foliar spray of Mg significantly increased leaf N, P, and Cu. A foliar spray of a complete micronutrient blend increased leaf Cu. Biomass production was correlated positively (decreasing order) with leaf Cu, N, and Mg and negatively with Zn. Leaf N was positively correlated with leaf P and calcium. The critical tissue concentrations (CTC) (where 90% of predicted maximum leaf protein was obtained) were 0.18% and 4.49 mg kg^-1 for leaf P and Cu, respectively. This revised version was published online in June 2006 with corrections to the Cover Date.     

Effects of seasonal changes on the population levels of some plant-parasitic nematodes in the plantations of Pinus caribaea and P. oocarpa in the savanna areas of Nigeria

The mean values of the total number of nematodes found in each of four pine plantations in Nigeria were depressed during the dry season to a minimum between March and April. A gradual increase in the population started from June–July, and the population reached its peak in August–October. The seasonal decline in nematode population coincided with the period of low soil moisture. An important ecological factor affecting population changes in the selected plantations was the vegetation cover; while a gradual decline in nematode population was observed in the 1968, 1974a and 1974b plantations, which have a full canopy, a sharp decline in nematode population was observed in the 1982 plot, which did not have a complete canopy. Populations of some nematode genera, such as Rotylenchus spp., Criconemella spp., Coslenchus spp. and Triversus spp., declined to zero in this last plantation.     

Antifilarial activity of Azadirachta indica on cattle filarial parasite Setaria cervi

Alcohol and aqueous extracts of flowers of Azadirachta indica were tested in vitro for their potential antifilarial activity against whole worm, nerve muscle (n.m.) preparation and microfilariae of Setaria cervi. The effects of alcohol and aqueous extracts were similar in nature on the spontaneous movements of whole worm and nerve muscle preparation. On the whole worm, the response was characterized by initial increase in tone, rate and amplitude of contractions followed by reversible paralysis. The initial stimulant effect is likely to be due to irritant effect on the cuticle. Nerve muscle preparation responded to both extracts by inhibition of spontaneous movements followed by reversible paralysis; initial stimulation phase was absent. The inhibition was concentration related. Alcohol and aqueous extracts had almost similar lethal effect on the microfilariae of S. cervi, the LC50 being 15 and 18 ng/ml, respectively.     

Antimicrobial activity of Cassia alata.

The methanol extracts of leaves, flowers, stem and root barks of Cassia alata showed a broad spectrum of antibacterial activity. The activity was increased on fractionation (petrol, dichloromethane, ethyl acetate), the dichloromethane fraction of the flower extract being the most effective. No activity was shown against tested moulds.     

Antidiarrhoeal activity of the bark extract of Careya arborea Roxb

The methanol extract of the Careya arborea Roxb. bark significantly reduced castor oil-induced diarrhoea in mice. This effect supports the local traditional use of the plant against diarrhoea.     

Development of Melampsora ciliata rust on nursery‐grown poplars in north‐western Himalayas

Development of leaf rust (Melampsora ciliata) in different species, hybrids and cultivars of poplar (Populus spp.) was studied in nursery‐grown plants. Five different criteria were used to assess the disease development. The mean disease index on 10 August was 9.4% which increased to 70.0% on 10 October. The lowest disease index (5.5%) was recorded in P. yunnanensis whereas the maximum was recorded in P. × euramericana‘Rubra‐Poiret’ (59.5%). The apparent infection rate per unit per day was highest in P. nigra × P. trichocarpa (9.7 × 10^–2) whereas the minimum occurred in P. maximowiczii × P. berolinensis‘Oxford’ (3.3 × 10^–2). The area under the disease progress curve was a maximum in P. × euramericana‘Rubra‐Poiret’ (26.7) and a minimum in P. yunnanensis (1.6). Complete defoliation by the first half of October occurred in P. nigra × P. trichocarpa, which also had the maximum apparent infection rate and area under the disease progress curve. Inoculum production was highest in P. nigra × P. trichocarpa and lowest in P. maximowiczii × P. berolinensis‘Oxford’.     

Invasion von Vorratsschädlingen durch Verschlüsse

Journal of Pest Science - Resistance of common packages of the brands ‘Schokini’, ‘Contessa’, ‘Hausgebackeness’, ‘Florentiner’ and...     

Seasonal population dynamics of Typhlodromus pyri Scheuten (Acari, Phytoseiidae) in apple orchards in the region Meckenheim

Typhlodromus pyri Scheuten (Acari, Phytoseiidae) has been reported as the most important predator of the European red mite, Panonychus ulmi (Koch) (Acari, Tetranychidae) in apple culture. However, biological data on T. pyri was insufficient on important parameters like seasonal population dynamics and within-tree and on-leaf distribution in apple orchards in the region of Meckenheim, Germany. The purpose of the present work was, therefore, to obtain experimental data on these parameters of T. pyri from 2000 to 2002 in the apple orchards in this region. The results showed that overwintered females of T. pyri reactivate and start laying eggs between late March and early April. The mean daily number of the different stages of T. pyri per leaf peaked in July each year, where it ranged between 0.92–1.68 eggs, 0.81–1.41 nymphs, 0.64–1.32 females and 0.37–0.52 males. A significantly higher number of T. pyri individuals congregated in the bottom layer of trees (0.34–0.64 individuals/leaf) than in the middle and top layers (0.23–0.38 and 0.12–0.23 individuals/leaf, respectively). We found that 91.4–94.1% of the total eggs, 89.6–91.7% larvae, 73.0–76.5% nymphs, 60.5–64.6% adult females and 52.6–55.9% adult males concentrated their activities in the inner area of the leaf surface. More than 50% of the predatory mites congregated in the bottom layer in winter. Mean total density of the overwintering females in December of 2000,2001 and 2002 ranged between 10.6–14.2 females/5 cm twig in the bottom, 7.3–10.4 in the middle and 4.1–6.9 in the top layers of the apple trees. Mean total fecundity recorded over the 3 years was lowest in the overwintering generation with 31.8–37.6 eggs/female, highest in the June generation with 45.9–53.7 eggs/female, and intermediate in the August generation with 41.5–46.1 eggs/female. The overwintering generation was composed entirely of females, while the female to male ratio in the June generation was 2:1, and in the August generation 3:1. T. pyri overwinters as adult females in rough structures, cracks and crevices of twigs.     

Antibacterial activity of Artocarpus heterophyllus

The crude methanolic extracts of the stem and root barks, stem and root heart-wood, leaves, fruits and seeds of Artocarpus heterophyllus and their subsequent partitioning with petrol, dichloromethane, ethyl acetate and butanol gave fractions that exhibited a broad spectrum of antibacterial activity. The butanol fractions of the root bark and fruits were found to be the most active. None of the fractions were active against the fungi tested.     

1-(3-Hydroxy-4-methoxy-5-methylphenyl) ethanone, a new compound from the stem bark of Lamprothamnus zanguebaricus

The chloroform extract of the stem bark of Lamprothamnus zanguebaricus has yielded two ethanones; 1-(3-hydroxy-4-methoxy-5-methylphenyl)ethanone (I) (a new compound) and 1-(3-hydroxy-4-methoxyphenyl)ethanone (II). The structures of both compounds were established by spectroscopic methods.