The selection of management strategies for controlling nematodes in cereals

Several genera and species of plant-parasitic nematodes cause losses in grain yield in cereals; some are of relatively minor importance (e.g. Anguina tritici (Steinbuch) Chitwood, the cause of “ear cockle” in wheat), while others such as the cereal cyst nematode (CCN) (Heterodera avenae Woll.) have a wide geographic distribution, infest extensive areas, and may cause losses valued at millions of dollars. Some of these nematodes are difficult to control because the measures that might be used are uneconomic to apply or are impractical. The control of CCN, however, can be achieved, and several successful strategies have been developed in parts of Europe and in Australia. The various measures available to Australian cereal growers include: crop rotation, resistant cultivars, manipulation of sowing dates, use of nematicides, and reduced cultivation. The selection of an appropriate management strategy for the control of CCN is influenced by factors such as: climate, cereal species grown, yield potential, rotations practised and the availability of alternative crops, pathotype present, farm size, availability of resistant cultivars, nematicides registered, and the availability of suitable equipment for their application.     

Inaction levels for the red imported fire ant, Solenopsis invicta (hym.: formicidae): A predator of the boll weevil, Anthonomus grandis (col.: curculionidae)

The density of red imported fire ants, Solenopsis invicta Buren (Hymenoptera: Formicidae), necessary to limit boll weevil abundance, Anthonomus grandis Boheman (Coleoptera: Curculionidae), below the action level was determined. An inaction level of 0.4 fire ants per shake bucket sample (i.e., four ants per 10 plant terminals) will provide boll weevil control approximately 90% of the time. A dynamic inaction level is also provided. Total mortality of boll weevil developmental stages including eggs through teneral adults averaged 97.9%. Of 100 boll weevil eggs deposited in cotton squares (flower buds), an average of two adults survive of which about half are female. Thus, the net replacement rate per generation (R_o is 1.0 which, in this case, indicates a stable boll weevil population.     

Heavy metal contamination of soils and crops from auto traffic,sewage sludge,pig manure and chemical fertilizer

The present paper describes heavy metal contamination of soils and crops resulting from auto traffic, sewage sludge, pig manure and chemical fertilizers, in three separate experiments.The first experiment revealed that although the ADDT (average annual daily traffic) value of the Agricultural Area was lower, higher concentrations of Cu, Cd, Zn, Pb and Mn were obtained in soil when compared with the Commercial-Residential Area. Contaminations of trace metals from various source, e.g., chemical fertilizer, animal manure, night soil and pesticides of the nearby agricultural land were suspected.The second experiment compared the effects of adding a commercial fertilizer and digested sludge which contain substantial amounts of various trace metals to a sandy loam for growing Chinese radish. The results indicated that repeated applications of the fertilizer elevated the contents of various trace metals in the roots of Chinese radish. The phenomenon was further aggravated when digested sludge was also incorporated.The third experiment compared the contents of trace metals in the root and leaf tissues of tree seedlings (Acacia confusa) added with a single dose of the trace metalenriched fertilizer, and different portions of pig manure compost. It was revealed that the fertilizer-treated tree seedlings had a higher content of trace metals in the tissues than those amended with manure compost. Although the metal contents of soil increased as more manure compost was added, the contents in plant tissues did not increase correspondingly.     

Chlorophyll-bleaching by atmospheric pollutants and sunlight

The Science of Nature -     

Prenatal diagnosis of campomelic dysplasia by ultrasonography

Consanguineous partners had a boy with campomelic dysplasia who died of increasing respiratory distress soon after birth. The next pregnancy was monitored frequently by ultrasonography and a healthy male infant was born at term. During a further pregnancy, ultrasonography suggested campomelic dysplasia in the 16th week of gestation. This was confirmed in the 18th week. The pregnancy was terminated and the fetus showed the typical radiological, anatomical and histological findings.     

Prenatal pleural effusion associated with congenital pulmonary lymphangiectasia

A pleural effusion associated with congenital pulmonary lymphangiectasia was detected in a fetus in utero but was absent at the time of delivery. The pleural effusion was unilateral although the disease involved both lungs. In this case there was an association between polyhydramnios and congenital pulmonary lymphangiectasia.     

Microphthalmia–prenatal ultrasonic diagnosis: A case report

Prenatal real-time ultrasonographic diagnosis of microphthalmia is presented. Diagnosis was made at 18 weeks' gestation in a fetus of a patient with a previous infant affected with the syndrome of cryptophthalmia with absence of septum nasi and ambiguous genitalia (Fraser syndrome). Recognition of microphthalmia as a part of Fraser syndrome and the easy visualization of fetal facial bones and orbits in the second trimester made the diagnosis possible.     

The fetal behavioural states: An ultrasonic study

In order to accurately detect the fetal behavioural state, we simultaneously measured fetal heart rate and multiple fetal activities in 27 healthy pregnant women at 38 to 40 weeks of gestation. We ultrasonically identified gross body movements, breathing movements and micturition. Analysis of fetal heart rate allowed us to distinguish two different patterns of fetal behaviour: active and quiet phases. The frequency distribution of the analysed fetal events was significantly different in these two phases. These data suggest that a complete biophysical profile of the fetus is effective in differentiating behavioural states and may improve the predictive accuracy of fetal heart rate analysis alone.     

The cerebro-hepato-renal (Zellweger) syndrome: Prenatal detection based on impaired biosynthesis of plasmalogens

Prenatal diagnosis of the cerebro-hepato-renal (Zellweger) syndrome has been performed in 10 pregnancies at risk by measuring both the activity of acyl CoA: dihydroxyacetonephosphate acyltransferase (DHAP-AT) and the de novo plasmalogen biosynthesis, either in cultured amniotic fluid cells or in fibroblasts cultured from a chorionic villus biopsy. In 7 of the pregnancies both tests indicated no abnormality. All 7 continued to term and normal infants were delivered. However, in amniotic fluid cells from 2 fetuses affected by Zellweger syndrome unequivocal differences from control values were found. The activity of DHAP-AT was clearly deficient and the de novo plasmalogen biosynthesis was impaired. In one pregnancy at risk prenatal diagnosis was performed during the first trimester by measuring both the DHAP-AT activity and the de novo plasmalogen biosynthesis in fibroblasts cultured from a chorionic villi biopsy. From the deficient DHAP-AT activity and the impaired de novo plasmalogen biosynthesis it was concluded that the fetus was affected. This was confirmed biochemically after induced abortion. It can be concluded that measurement of the DHAP-AT activity and the de novo plasmalogen biosynthesis provides convenient methods for the early prenatal detection of Zellweger syndrome.     

Lost benefits and carbon uptake by protection of Indian plantations

There is a range of problems in assessing how protection of a specific forest to Reduce Emissions from Deforestation and forest Degradation (REDD+) affect global emissions of greenhouse gases. This paper shows how knowledge and information about the biophysical characteristics of forests can be combined with theories of forest management and economic behaviour to derive the impacts on global emissions of REDD+. A modelling experiment from India, where 10% of the forest plantations in eight different regions are protected, shows that the biophysical characteristics of forests are decisive for the global impacts on emissions. In regions with slow-growing forests, agents in the non-protected forests are able to increase their output significantly to fill the demand from the protected forests. This opportunity is strictly limited in regions with fast-growing forests. Therefore, prices increase far more in regions with fast-growing forests than in slow-growing forests. Over time, the markets for Indian forestry products contribute to reduce the resulting price differences across regions. When the carbon uptake from protected forests approaches zero, the leakage of emissions to other Indian forests is between 20 and 40%. Only a small part of this is international leakage. Combining different models also helps to identify knowledge gaps, and to distinguish gaps that potentially may be filled with data and new knowledge, and gaps due to different angling of modelling biophysical processes and modelling of economic behaviour.