BIOLOGICAL TECHNIQUES

INSECT COLLECTION TECHNIQUES

1. Sweep net sampling

Collections of flying insects, or those inhabiting foliage, can be made using a sweep net. Several types of nets are available, with standard sizes being either 30.5 cm (12 in) or 38 cm (15 in) diameter. Aerial nets (net on the right) have an open mesh collection bag and are used mainly to capture flying insects, although they can be swept through light vegetation such as tall grass. Beating nets (net on the left) are made from canvas and are used to sweep through vegetation that could snag and tear a mesh bag. A sweep is a single back and forth sweep covering a 150⁰ to 180⁰ arc. Collected insects can be identified and counted live in the net, or placed in a container with a piece of paper towel soaked with non-acetone nail polish remover to kill them to facilitate counting.

 

2. Leaf litter sampling

Insects that inhabit leaf litter or mulch can be surveyed by placing some of this material in an apparatus know as a Berlese-Tullgren funnel, which is designed to separate insects from the litter. A simple funnel can be constructed by removing the bottom from a potable water bottle and placing a piece of 0.6 mm (1/4 in) mesh hardware cloth inside the neck of the bottle. The inverted bottle should be  supported over a container to collect the insects that come out of the litter. To facilitate the movement of insects from the litter, a 15W to 25W bulb placed over the funnel will cause the insects to move deeper into the litter, through the screen, and into the container. The preservative in the container can be 75 to 80% ethanol.

3. Light trap sampling

Although insects have good color vision, they do not see the same wavelengths of light as humans. The human eye can typically distinguish colors ranging from red (760 nm [nanometers]) to purple (380 nm), while it has been shown that most insects see colors from yellow / green (550 nm) to ultraviolet [UV] (340 nm). Since many nocturnal insects are attracted to UV, trapping or killing devices have been developed that use UV bulbs to attract insects either to a collection container (we call these light traps) or to an electric grid (we call these bug zappers). Because insects do not perceive light in the red to yellow range, we use yellow bug lights outdoors to reduce the number of insects attracted to areas around our homes. Since most humans see relatively well under yellow light, these bulbs allow us to see while not attracting many insects. A simple light trap design is illustrated below. It’s construction is also described. Traps can be built either as single units or as a series of lights that can be used to allow comparison among bulbs of different colors, from several manufacturers, or having different wattage.

 

4. Pitfall trapping.

Pitfall traps are collect populations of insects and other arthropods living on the ground surface. Typically, traps are set up and allowed to collect insects for a minimum of 24 hours. The basic trap consists of a container set into the ground so that the upper rim is flush with the ground surface. Since many insects are predators and will eat other insects in the trap, a solution to kill and preserve insects entering the trap is used.

5. Aquatic insect collections using D-framed nets

These nets have a opening with a flat side (the D part) (at left). They can be used like a kick-net, with the flat side placed on the stream bottom so that it collects organisms dislodged when submerged objects upstream are disturbed. It also can be used more like a dip net and scraped along submerged objects to dislodge and collect organisms, or the flat side can be pulled across the bottom sediments of a pond or stream to sample organisms in that habitat.

 

Note: This post is still undergoing developments. Please update constantly.

BIO 101 (BASIC PRINCIPLES OF BIOLOGY) (3 UNITS)

CONTENT: Levels of biological organisation and basic characteristics of living things. Microscope concepts.  Macromolecules, carbohydrates, lipids, proteins and nucleic acids. Cell structure and function of organelles. Basic Principles of reproduction – Mitosis and growth; Meiosis and gametogenesis. Inhertance and variation.  Evolutionary trends.

GENERAL HISTOLOGY ASSIGNMENT ON HISTOTECHNIQUES
Write brief notes on
 (i) Autoradiography
(ii) Immunocytochemstry

Submit your assignment here. Be sure to include your name and matric number..

Future Cars That Will Crash the Economy of Nigeria, Wont need fueling for 100 years!

Do you remember that advert by a defunct commercial Bank? It says “Cars will soon run on water as fuel”. It was catchy but incredible. Now, cars may soon run not on water as fuel, but on an element called Thorium and will be fuelled once in 100 years! It is estimated that there are over one billion cars traveling roads around the world directly and indirectly costing trillions of dollars in material resources, time and noxious emissions. Imagine all these cars running cleanly for 100 years on just 8 grams of fuel each.

Laser Power Systems (LPS) from Connecticut, USA, is developing a new method of automotive engines with one of the most dense materials known in nature called thorium. Thorium is so dense it has the potential to produce tremendous amounts of heat. The company has been experimenting with small bits of thorium, creating a laser that heats water, produces steam and powers a mini turbine.

Current models of the engine weigh 500 pounds, easily fitting into the engine area of a conventionally-designed vehicle. According to CEO Charles Stevens, just one gram of the substance yields more energy than 7,396 gallons (28,000 L) of gasoline and 8 grams would power the typical car for a whopping 100 years.

Thorium Fuel Concept Car

The idea of using thorium first came up in 2009 when Loren Kulesus designed the Cadillac World Thorium Fuel Concept Car (see pic). LPS is developing the technology so it can be mass-produced. The car to run on thorium promises to reduce Co2 emissions and will ultimately displace fossil fuels. Thorium produces 10 to 10,000 times less long-lived radioactive waste. This is a  big threat to crude oil based economies like Nigeria. The penchant of Nigerians for cars will be an added advantage for the Throium car companies to enjoy patronage from the country even at the detriment of the economy.

Transgenic crops and Biosafety Issues take front row as Bangledeshi Government take steps to introduce genetically modified cotton

The use of Genetically Modified Organisms is fast gaining ground. It has been reported that the government of Bangladesh has made a move to introduce genetically modified (GM) cotton varieties at farmers’ level in the country.  The seeds of the GM variety named Bt cotton would be directly imported from Indian seed producer Maharashtra Hybrid Seeds Company (Mahyco) or other companies from China. Dhakar Tribune reports.

Cotton boll.

The Cotton Development Board (CDB) has already decided to import the Bt variety and has sent an application to the agriculture ministry so that they could forward the application to the environment ministry, who will give the final approval to demonstrate any GM crop variety on farmers level. The authorities are hoping to run a “confined trial” of Bt variety from next season during June-July of 2014.

Muhammad Solaiman Haider, member secretary of the National Committee on Bio-safety under the environment ministry, told the Dhaka Tribune, they would look into the matter after getting the application from the agriculture ministry. Genetically modified crops like cotton, golden rice, Bt brinjals and potatoes are “transgenic” crops, and need special approval from bio-safety authorities for field trials.

Bt cotton is a variety developed through genetic engineering by inserting crystal protein genes taken from the soil bacterium Bacillus thuringiensis, popularly known as Bt.

The CDB hopes that the Bt Cotton will increase the yield of cotton owing to its to prevent “American Bollworm,” infestation, one of the biggest threats to cotton. This is however contentious as it has been speculated that introducing Bt cotton in Bangladesh may not yield any result as the American Bollworm’s tendency to attack cotton had been reduced remarkably in recent years. So the crave for Bt Cotton becomes a debetable issue.

According to Bangladesh Textile Mills Association (BTMA), the country requires 3.5m to 4m bales of raw cotton to run approximately 363 textile mills for meeting the spinning demands of the country’s garment sector. Against the demand, the country only produces around 150,000 bales by using around 40,000 hectares of arable land, said sources at the CDB.

Only about 2% to 3% of the national requirement has been met through local production, while the rest was fulfilled by importing raw cotton from Uzbekistan, India, USA, Australia, Pakistan and some African countries.

Last month (October), the government of Bangladesh released four GM brinjal varieties at farmers’ level to demonstrate on a limited scale, but environment activists have raised concerns that the health impact of Bt brinjal was yet to be scrutinised. Checks however revealed that the concerns of the activists may be grossly misplaced; a report of an expert committee (EC II) on Bt Brinjal EE1 dated October 8, 2009 by M/S Maharashtra Hybrid Seed Company, India and two Indian universities submitted to the Genetic Engineering Approval Committee, Ministry of Environment and Forests, Inida shows that extensive toxiciological assessment was carried out on Bt Brinjal (see http://envfor.nic.in/sites/default/files/Report%20on%20Bt%20brinjal_2.pdf for details). The last has definately not been heard about the planned introduction of Bt Cotton.

AGENDA FOR MARIE MILLER, MISS EARTH NGIERIA 2013

On Saturday December 7th 2013 the next Miss Earth would be crowned at the F1 Hotel, Phillipines and she would be taking over from the current crown holder, Tereza Fajkisova of Chech Republic. For Nigeria, the journey to the finale in the Phillipines has started  with Marie Miller crowned as the Miss Earth Nigeria 2013 last Sturday 22nd September 2013. Congratulations Marie, and here’s hoping she clinches the ultimate crown.

Marie Miller, Miss Earth Nigeria 2013

Miller (Photo Credit: Bella Naija)

The Miss Earth pageant is a show put together in the last 13 years by Carousel Productions Inc. With a track record in mounting world-class beauty pageants, Carousel decided to reinvent and improve the concept of beauty competitions for the new millennium. It is the belief of Carousel that a beauty queen would be a good and effective advocate of worthy causes since many people aspire to become queens. One of such worthy causes is environmental conservation. Carousel consequently launched the Miss Earth Beauty Pageant in 2001.  The Pageant is a beauty event which raison d'etre was to have its candidates and winners actively promote and get involved in the preservation of the environment and the protection of Mother Earth. Apart from a strong emphasis on environmental protection, MISS EARTH also aims to showcase and promote various tourist destinations.In the Pageant, 80 to 90 candidates from all over the world compete on beauty and knowledge of environmental issues each year. The winner of MISS EARTH is a gloal ambassador for environmental protection campaigns.

TABLE 1: PREVIOUS  MISS EARTH TITLE HOLDERS

SN	NAME	TITLE YEAR	COUNTRY
1	TEREZA FAJKISOVA	2012	Czech Republic
2	OLGA ALAVA	2011	Ecuador
3	NICOLE FARIA	2010	India
4	LARISSA RAMOS	2009	Brazil
5	KARLA HENRY	2008	Philippines
6	JESSICA TRISKO	2007	Canada
7	HIL HERNANDEZ	2006	Chile
8	ALEXANDRA BRAUN	2005	Venezuela
9	PRISCILLA MEIRELLES	2004	Brazil
10	DANIA PRINCE	2003	Honduras
11	WINIFRED OMWAKWE	2002	Kenya
12	CATHARINA SVENSSON	2001	Denmark

 

 

MARIE MILLER, THE TASK AHEAD

With her win Marie Miller received a 2013 Model Toyota Avensis and one year salary of three million naira. Eyeing the coveted world Miss Earth 2013 means hard work, and the work is truly worth it. The incumbent Title Holder, Tereza Fajkisova, has been traveling around the world just as the previous winners (Table 1) and engaged in many environmental capaign activities including Tree Planting. Tereza has travelled to Sri Lanka, Indonesia, Marutitius, Cote D’Ivore, South Sudan, Kenya, Ghana, Finland, Indonesia, to mention a few.

 

Chief Newton Jibunoh; FADE

The miss Earth Nigeria 2013 will face the onerous task of visiting place of environmental interests and disasters in Nigeria to keep faith with the dictum that charity begins at home. For instance she should be a living tool to call attention with visits to the Niger Delta for the monumental pollution of the sea and inland waters by the multi nationals, particpation in tree planting excercises in various states, tin minning woes in Jos, growing refuse heaps in major cities of Nigeria including Lagos. Her visible presence and audible voice would be invaluable in collaborations with environmental conservations organizations including those of Chief Newton Jibunoh’s Fight Against Desert Encroachment (FADE),  Nigerian Conservation Foundation (NCF), and Nigeria’s National Park Service (NPS) and so on.

BIOACTIVITY OF EXTRACTS OF SOME NIGERIAN PLANTS ON INSECT PESTS OF STORED GRAINS

BY

ABIODUN AKINPELU DENLOYE

ABSTRACT

Five of the plant species used by farmers in southwestern Nigeria, Chenopodium ambrosioides (L), Tephrosia vogelii (Hook), Allium sativum (Linn), Allium fistulosum (Linn) and Zanthoxylum zanthoxyloides (Linn) were tested for their bioactivity against Sitophilus zeamais Motsch, Callosobruchus maculatus F., and Tribolium casteneum Herbst in laboratory and field bioassays. The selected plants were tested as powders, aqueous extract, ethanol extracts and volatile essential oils for toxicity, ovicidal, antiovipositional, and larvicidal effects as admixtures, dipped grain treatments or fumigants. On the basis of 48 hr LC₅₀ values Z. zanthoxyloides powder was the most toxic to S. zeamais (0.012 g/kg), T. casteneum (0.041 g/kg) and C. maculatus (0.05 g/kg) followed by C. ambrosioides with 0.49 g/kg (S. zeamais), 1.634 g/kg (C. maculatus) and 2.57 g/kg (T. casteneum) 48 h LC₅₀ values.  Ethanol extract of all test plant species were more toxic than their equivalent aqueous extracts. Values of the 48 h LC₅₀ show that Z. zanthoxyloides ethanol extract was more toxic to C. maculatus (0.021 g/L) than S. zeamais (0.035 g/L) or T. casteneum (0.085 g/L). Insecticidal activity of Z. zanthoxyloides ethanol extract persisted for 14 days post-treatment whereas there was measurable loss of activity for C. ambrosioides and T. vogelii respectively at 24 h post-treatment while A. sativum and A. fistullosum activity was lost as from 12 h post treatment. The essential oils of A. sativum, A. fistullosum and C. ambrosioides demonstrated fumigant toxicity against C. maculatus with a 24 hr LC₅₀ value of 1.33 μl/L) and S. zeamais (1.90 μl/L). Grain treatment with ethanol extracts resulted in significant reduction (p > 0.05) in the number of eggs laid by C. maculatus; fewer eggs were laid in Z. zanthoxylum-treated than Chenopodium extract treated grains. Only C. ambrosioides volatile oil gave appreciable ovicidal action against eggs of C. maculatus on cowpea (LC₅₀ = 2.066 μl/L).   Zanthoxylum zanthoxyloides gave protection from insect infestation in field tests for up to 180 days post-treatment just as pirimiphos methyl (Actellic) while protection with C. ambrosioides failed 90 days post treatment in treated cowpea and maize grains. Grain treatment did not result in loss of viability in Z. zanthoxyloides – treated grains but treatments in C. ambrosioides – treated grains did. The results obtained from this study show that the test plant species especially Z. zanthoxyloides, C. ambrosioides and T. vogelii can be exploited as sources of locally available alternative insecticides for the protection of grains against attack by C. maculatus and S. zeamais. The study further shows that the volatile oil of C. ambrosioides can be used as fumigant to reduce the number of eggs laid by C. maculatus or reduce their hatchability thus reducing the number of offspring in the succeeding generation.

 

ABSTRACT OF THESIS SUBMITTED TO THE SCHOOL OF POSTGRADUATE STUDIES, UNIVERSITY OF LAGOS IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY (Ph. D) IN ZOOLOGY (2008)