Wednesday 25 May 2011

Sea Slug


A green sea slug appears to be part animal, part plant. It's the first critter discovered to produce the plant pigment chlorophyll.
The sneaky slugs seem to have stolen the genes that enable this skill from algae that they've eaten. With their contraband genes, the slugs can carry out photosynthesis.
"They can make their energy-containing molecules without having to eat anything," said Sidney Pierce, a biologist at the University of South Florida in Tampa.
Pierce has been studying the  unique creature, officially called Elysia chlorotica, for about 20 years. He presented his most recent findings Jan. 7 at the annual meeting of the Society for Integrative and Comparative Biology in Seattle. The finding was first reported by Science News.
"This is the first time that multi cellar animals have been able to produce chlorophyll," Pierce told LiveScience.
The sea slugs live in salt marshes in New England and Canada. In addition to burglarizing the genes needed to make the green pigment chlorophyll, the slugs also steal tiny cell parts called chloroplasts, which they use to conduct photosynthesis. The chloroplasts use the chlorophyll  to convert sunlight into energy, just as plants do, eliminating the need to eat food to gain energy.
"We collect them and we keep them in aquarium for months," Pierce said. "As long as we shine a light on them for 12 hours a day, they can survive [without food]."
The researchers used a radioactive tracer to be sure that the slugs are actually producing the chlorophyll themselves, as opposed to just stealing the ready-made pigment from algae. In fact, the slugs incorporate the genetic material so well; they pass it on to further generations of slugs.
The babies of thieving slugs retain the ability to produce their own chlorophyll, though they can't carry out photosynthesis until they've eaten enough algae to steal the necessary chloroplasts, which they can't yet produce on their own.
The slugs accomplishment is quite a feat, and scientists aren't yet sure how the animals actually appropriate the genes they need.
"It certainly is possible that DNA from one species can get into another species, as these slugs have clearly shown," Pierce said. "But the mechanisms are still unknown
By Clara Moskowitz
LiveScience
updated 1/12/2010 2:50:19 PM ET 2010-01-12T19:50:19


Photosynthesis



Photosynthesis is a process in which green plants use energy from the sun to transform water, carbon dioxide, and minerals into oxygen and organic compounds. It is one example of how people and plants are dependent on each other in sustaining life.
Photosynthesis happens when water is absorbed by the roots of green plants and is carried to the leaves by the xylem, and carbon dioxide is obtained from air that enters the leaves through the stomata and diffuses to the cells containing chlorophyll. The green pigment chlorophyll is uniquely capable of converting the active energy of light into a latent form that can be stored (in food) and used when needed.
The initial process in photosynthesis is the decomposition of water (H2O) into oxygen, which is released, and hydrogen; direct light is required for this process. The hydrogen and the carbon and oxygen of carbon dioxide (CO2) are then converted into a series of increasingly complex compounds that result finally in a stable organic compound, glucose (C6H12O6), and water. This phase of photosynthesis utilizes stored energy and therefore can proceed in the dark. The simplified equation used to represent this overall process is 6CO2+12H2O+energy=C6H12O6+6O2+6H2O. In general, the results of this process are the reverse of those in respiration, in which carbohydrates are oxidized to release energy, with the production of carbon dioxide and water.
The intermediary reactions before glucose is formed involve several enzymes, which react with the coenzyme ATP (see adenosine triphosphate) to produce various molecules. Studies using radioactive carbon have indicated that among the intermediate products are three-carbon molecules from which acids and amino acids, as well as glucose, are derived. This suggests that fats and proteins are also products of photosynthesis. The main product, glucose, is the fundamental building block of carbohydrates (e.g., sugars, starches, and cellulose). The water-soluble sugars (e.g., sucrose and maltose) are used for immediate energy. The insoluble starches are stored as tiny granules in various parts of the plant—chiefly the leaves, roots (including tubers), and fruits—and can be broken down again when energy is needed. Cellulose is used to build the rigid cell walls that are the principal supporting structure of plants.





Saturday 21 May 2011

Plant Micronutrient Functions (part 2)

Manganese
Manganese is needed   during photosynthesis, nitrogen metabolism and to form other compounds required for plant metabolism.  For severe shortage of manganese intake, brown necrotic spots appear on leaves and resulting in leaf drop prematurely. For some plants, deficiency of manganese intake results in late maturity.
Manganese deficiencies mainly occur on organic soils, high-pH soils, sandy soils low in organic matter, and on over-limed soils. Soil manganese may be less available in dry, well-aerated soils, but can become more available under wet soil conditions when manganese is reduced to the plant-available form. Conversely, manganese toxicity can result in some acidic, high-manganese soils. Uptake of manganese decreases with increased soil pH and is adversely affected by high levels of available iron in soils.
Molybdenum
Molybdenum is involved in enzyme systems relating to nitrogen fixation by bacteria growing symbiotically with legumes. Nitrogen metabolism, protein synthesis and sulphur metabolism are also affected by molybdenum. Molybdenum has a significant effect on pollen formation, so fruit and grain formation are affected in molybdenum-deficient plants. Because molybdenum requirements are so low, that most plants do not exhibit molybdenum-deficiency symptoms. These deficiency symptoms in legumes are mainly exhibited as nitrogen-deficiency symptoms because of the primary role of molybdenum in nitrogen fixation. Unlike the other micronutrients, molybdenum-deficiency symptoms are not confined mainly to the youngest leaves because molybdenum is mobile in plants. The characteristic molybdenum deficiency symptom in some vegetable crops is irregular leaf blade formation known as whiptail, but interveinal mottling and marginal chlorosis of older leaves also have been observed.
Molybdenum deficiencies are found mainly on acidic, sandy soils in humid regions. Molybdenum uptake by plants increases with increased soil pH, which is opposite that of the other micronutrients. Molybdenum deficiencies in legumes may be corrected by liming acid soils rather than by molybdenum applications. However, seed treatment with molybdenum sources may be more economical than liming in some areas.
Zinc
Zinc is an essential component of various enzyme systems for energy production, protein synthesis, and growth regulation. Zinc deficient plants also exhibit delayed maturity. Zinc is not mobile in plants so zinc-deficiency symptoms occur mainly in new growth. Poor mobility in plants suggests the need for a constant supply of available zinc for optimum growth. The most visible zinc deficiency symptoms are short internodes and a decrease in leaf size. Delayed maturity also is a symptom of zinc-deficient plants.
Zinc deficiencies are mainly found on sandy soils low in organic matter and on organic soils. Zinc deficiencies occur more often during cold, wet spring weather and are related to reduced root growth and activity as well as lower microbial activity decreases zinc release from soil organic matter. Zinc uptake by plants decreases with increased soil pH. Uptake of zinc also is adversely affected by high levels of available phosphorus and iron in soils.
Chloride
Because chloride is a mobile anion in plants, most of its functions relate to salt effects (stomata opening) and electrical charge balance in physiological functions in plants. Chloride also indirectly affects plant growth by stomata regulation of water loss. Wilting and restricted, highly branched root systems are the main chloride-deficiency symptoms, which are found mainly in cereal crops.
Most soils contain sufficient levels of chloride for adequate plant nutrition. Chloride deficiencies have been reported on sandy soils in high rainfall areas or those derived from low-chloride parent materials. There are few areas of chloride-deficient so this micronutrient generally is not considered in fertilizer programs.  The role of chloride in decreasing the incidence of various diseases in mall grains is perhaps more important than its nutritional role from a practical viewpoint.

Friday 20 May 2011

Plant Micronutrient Functions (part 1)

Boron
The function of boron is for the wall formation, so boron-deficient plants may be stunted. Sugar transport in plants, flower retention and pollen formation and germination also are affected by boron.Insufficient of boron intake result in reduction of  seed and grain production . Boron-deficiency symptoms first appear at the growing stage. This results in a stunted appearance (resetting), barren ears due to poor pollination, hollow stems and fruit (hollow heart) and brittle, discoloured  leaves and loss of fruiting bodies.
Boron deficiencies are easily detected  in acid, sandy soils in regions of high rainfall, and those with low soil organic matter. Borate ions are mobile in soil and can be leached from the root zone. Boron deficiencies are more prominient during dry periods when root activity is restricted.
Copper
Copper is needed for carbohydrate and nitrogen metabolism and, inadequate copper results in stunting of plants. Copper also is required for lignin synthesis which is needed for cell wall strength and prevention of wilting. The sign of deficiency  in copper are dieback of stems and twigs, yellowing of leaves, stunted growth and pale green leaves that wither easily.
Copper deficiencies are mainly happened  on sandy soils which are low in organic matter. Copper uptake decreases as soil pH increases. Increased phosphorus and iron availability in soils decreases copper uptake by plants
Iron
Iron is involved in the production of chlorophyll, and iron chlorosis is easily recognized on iron-sensitive crops growing on calcareous soils. Iron also is a component of many enzymes associated with energy transfer, nitrogen reduction and fixation, and lignin formation. Iron is associated with sulphur  in plants to form compounds that catalyse other reactions. Iron deficiencies are mainly manifested by yellow leaves due to low levels of chlorophyll. Leaf yellowing first appears on the younger upper leaves in inte veinal tissues. Severe iron deficiencies cause leaves to turn completely yellow or almost white, and then brown as leaves die.
Iron deficiencies occured on high pH soils, although some acid, sandy soils that is low in organic matter also may be iron-deficient. Cool, wet weather enhances iron deficiencies, especially on soils with marginal levels of available iron. Poorly aerated or compacted soils also reduce iron uptake by plants. Uptake of iron decreases with increased of  soil pH, and is adversely affected by high levels of available phosphorus, manganese and zinc in soils.

Tuesday 17 May 2011

Misai Kucing (Orthosiphon Stamineus)

                                                 Flowering   time (white or dark purple flower)


                                                                         Structure of stem

Morphological characteristics

This herb grow fast and could easily could reach 1.5 m in height. The stem is square, short hairy or red-colored gondola, grow upright and branching.  The leaves are arranged in opposite pairs, smooth, dark green, conical shape at the tip and finger like leave.
A short petiole , about 0.3m length and purple-red.

In our country, we categorized based on the color of the flower, which is white and dark purple. The white flower is recognized as MOS 1 and MOS 2 as dark purple herb .  Mos 1 has a bigger canopy, higher trunk and more fertile look(bigger size). Mos 1  has a  faster and more  twig growth compare to Mos 2  .

This herb is easy to plant and suitable for any kind of soil including sandy soil such as  bris soil  and alluvium soil . For a healthy and fruitful growth an average rain per month of  180-200cm. During dry season need irrigation.

If the plant is lack of water, the leaves are small, hard and brittle. Compare with other plant, this plant can with stand stagnant water up to  24 hour . These plants need a moist area for maximum vegetative growth.  For bris soil, this plant  needs   30-40% shading  especially during dry season  (Jan-Jun)

Land preparation

Planted area is usually plowed at least one month before planting.  This is to ensure that weeds and shrubs are cleared and eliminated.   Calcification with grounded magnesium limestone (GML) was conducted after the first fertilization. This activity ensure the soil mix and blend well with the GML
The amount of GML usage depends on the soil pH. The optimum soil pH is between 5.5 to 6


Planting preparation

The plant is  propagated by  cutting the stem at  6 inches All the stem section can be used as to plant.
The cut stems are planted in poly bags,  roots began to grow  after 2 weeks. The seedlings can be converted to farm after  4-5 weeks after sowing

Farming

The recommended planting distance is 60cm x 60cm.. The distance of these plants will produce a density of 25,000 per hectare

Fertilization

The recommended fertilizer rates are 75 kg / ha urea  for  every 3 times during  harvesting  or every  6-9 weeks . Compound or bio fertilizer  is sown in shallow run between rows of crops and covered the ground immediately.    

Irrigation system

There are a few irrigation system to be used depend on soil condition and water source.  For commercial planting, rotating or spinning irrigation system is suitable .
Drip irrigation system is ideal when used plastic mulch.

Nutritional content and  usage

Misai  kucing has been used since the old days to cure kidney disease  and  kidney stone.
Ortosifonim content and potassium salts (found in the leaves) is the main component  that dissolve uric acid, phosphate and oxalate  in our body bile and kidney. Saponin and tannin content in leaves can cure diseases suffered by  women whom are pale . This herb also can use as anti-allergy