Tuesday, March 25, 2014

Environmental Conditions for Growing Coffee

Related Posts Plugin for WordPress, Blogger...

Very little crops receive so much attention in respect to its relation with the environment as does coffee. Coffee is produced in tropical and subtropical areas, and is considered a "North" - "South" product. Coffee is a tropical plant which grows between the latitudes of 25 degrees North and 25 degrees South but requires very specific environmental conditions for commercial cultivation. Temperature, rainfall, sunlight, wind and soils are all important, but requirements vary according to the varieties grown. Robusta coffee is grown at much lower altitudes (sea level-3000 feet) in an area 10° North and South of the equator (Illy, 22).  It is much more tolerant to warm conditions than Arabica coffee.

For growing Arabica coffee beans, there are two optimal growing climates:
1.       The subtropical regions, at high altitudes of 16-24° (Illy, 21).  Rainy and dry seasons must be well defined, and altitude must be between 1800-3600 feet.  These conditions result in one coffee growing season and one maturation season, usually in the coldest part of autumn.  Mexico, Jamaica, the S. Paulo and Minas Gerais regions in Brazil, and Zimbabwe are examples of areas with these climate conditions (Illy, 21).
2.       The equatorial regions at latitudes lower than 10° and altitudes of 3600-6300 feet (Illy, 21).  Frequent rainfall causes almost continuous flowering, which results in two coffee harvesting seasons.  The period of highest rainfall determines the main harvesting period, while the period of least rainfall determines the second harvest season. Because rainfall is too frequent for patio drying to occur,  artificial drying with mechanical dryers is performed in this type of coffee growing environment. Examples of countries that have this climate are Kenya, Colombia, and Ethiopia (Illy, 21).

Ideal average temperatures range between 15 to 24ºC for Arabica coffee and 24 to 30ºC for Robusta, which can flourish in hotter, drier conditions but does not tolerate temperatures much below 15ºC, as Arabica can for short periods. All coffee is easily damaged by frost, a danger either in southern Brazil or, closer to the Equator, at altitudes around 2000 metres.

Sertani produces high-yielding rice variety

Related Posts Plugin for WordPress, Blogger...

Indonesian Farmers Union (Sertani) was successful in discovering varieties of paddy seeds claimed capable to rival hybrid rice in terms of productivity and resistant  pest attack planthopper. This variety was discovered by Surono Danu, seed breeders who did research in Lampung.

Sertani-1 variety had a higher yield than other rice varieties and required a shorter growing period. The variety also requires less fertilizer and water and is more resistant to plant diseases. Sertani-1 is suitable for dry fields, while Emespe is suitable for land with lots of water. This means that Sertani-1 is good for land that lacks water. So farmers do not need to worry about growing paddy in the dry season.

One hectare of Sertani-1 rice can produce up to 14 tons of unhulled paddy. the Sertani-1 paddy stalk produced around 400-450 grains, while other varieties produced about 200 grains. The seeds do not need special treatment or much water because they can absorb more oxygen. The seeds grow well in many different areas, such as in land that is dry, nonirrigated or even saline and could be planted just one centimeter above the surface of the land.

Sertani-1 seeds have their own antibodies so they are more resistant to diseases. Sertani-1 rice also requires less fertilizer and it is more resistant to plant diseases and crop pests such as rats: A paddy stem bitten by a rat can recover within 24 hours and still grow well.

After an initial trial in Lampung, Sertani-1 is now widely used across Indonesia: Many farmers have planted the seeds and enjoyed the harvest. Sertani-1 and MSP varieties were planted for pilot projects in West Java, Central Java, East Java and North Sumatra. In the next few years, members of the Lampung chapter of Sertani hope to develop the seeds all over Indonesia.

Surono, together with farmers in Lampung in the Indonesian Farmers Union (Sertani), are now developing another genetically altered rice variety called Emespe or MSP, which stands for Mari Sejahterakan Petani (let's make farmers prosperous).

Monday, April 1, 2013

Effect of NaCl treatments on glucosinolate metabolism in broccoli sprouts

Related Posts Plugin for WordPress, Blogger...

Rong-fang Guo, Gao-feng Yuan, and Qiao-mei Wang (J Zhejiang Univ Sci B)

Glucosinolate-myrosinase is a unique substrate-enzyme system, in which myrosinases are responsible for glucosinolate turnover. The sprouts of broccoli (Brassica oleracea var. italica) are rich sources of glucosinolates and their hydrolysis products. However, limited information is available about the influence of NaCl treatments on the metabolism of glucosinolates in broccoli sprouts. The aim of the present study was to evaluate the glucosinolate metabolism in broccoli sprouts under NaCl treatment by determining the glucosinolate composition and their contents. The activity of its hydrolysis enzyme, myrosinase, and the content of the main hydrolysis product, sulforaphane, in broccoli sprouts were also analyzed in the present study.To understand the regulation mechanism of NaCl on glucosinolate metabolism in broccoli sprouts, the germination rate, fresh weight, contents of glucosinolates and sulforaphane, as well as myrosinase activity of broccoli sprouts germinated under 0, 20, 40, 60, 80, and 100 mmol/L of NaCl were investigated in our experiment. The results showed that glucoerucin, glucobrassicin, and 4-hydroxy glucobrassicin in 7-d-old broccoli sprouts were significantly enhanced and the activity of myrosinase was inhibited by 100 mmol/L of NaCl. However, the total glucosinolate content in 7-d-old broccoli sprouts was markedly decreased although the fresh weight was significantly increased after treatment with NaCl at relatively low concentrations (20, 40, and 60 mmol/L). NaCl treatment at the concentration of 60 mmol/L for 5 d maintained higher biomass and comparatively higher content of glucosinolates in sprouts of broccoli with decreased myrosinase activity. A relatively high level of NaCl treatment (100 mmol/L) significantly increased the content of sulforaphane in 7-d-old broccoli sprouts compared with the control. These results indicate that broccoli sprouts grown under a suitable concentration of NaCl could be desirable for human nutrition.
NaCl treatment has a concentration-dependent effect on glucosinolate-myrosinase system in broccoli sprouts. NaCl treatments at relatively low concentrations enhanced the growth of the broccoli sprouts. NaCl treatment at the concentration of 60 mmol/L for 5 d maintained higher biomass and comparatively higher content of glucosinolates in broccoli sprouts with decreased myrosinase activity. The application of high concentration, especially 100 mmol/L of NaCl, for 3 d can endow broccoli sprouts with abundant glucosinolates and sulforaphane. The 100 mmol/L NaCl treatment significantly increased the sulforaphane content in 7-d-old broccoli sprouts as compared to the control. These results indicate that broccoli sprouts grown under a suitable concentration of NaCl could be desirable for human nutrition.

Monday, March 11, 2013

Biofertilizers for be safe alternative to remove using chemical fertilizers

Related Posts Plugin for WordPress, Blogger...

Biofertilizers are the most advanced biotechnology necessary to support developing organic Agriculture, sustainable agriculture, green agriculture and non-pollution agriculture. Bio Fertilizer are natural and organic fertilizer that helps to keep in the soil with all the nutrients and live microorganisms required for the benefits of the plants. Today product like biofertilizers using the biotechnology techniques have proved that biological control is widely regarded as a desirable technique for controlling insects and pests, due to its minimal environmental impact and its avoidance of problems of resistance in the vectors and agricultural pests.

Increasing use of chemical fertilizers in agriculture make country self dependent in food production but it deteriorate environment and cause harmful impacts on living beings. Due to insufficient uptake of these fertilizers by plants results, fertilizers reaches into water bodies through rain water, causes eutrophication in water bodies and affect living beings including growth inhabiting micro organism. The excess uses of chemical fertilizers in agriculture are costly and also have various adverse effects on soils i.e. depletes water holding capacity, soil fertility and disparity in soil nutrients. It was felt from a long time to develop some low cost effective and eco-friendly fertilizers which work without disturbing nature. Now, certain species of micro-organism are widely used which have unique properties to provide natural products, and serve as a good substitute of chemical fertilizers.
At this critical juncture, biofertilizers are useful supplement to chemical fertilizers. Organic farming has emerged as the only answer to bring sustainability to agriculture and environment. Biofertilizers is also an ideal for practicing organic farming.
What is biofertilizer?
A number of micro-organisms (bacteria fungi and algae) are considered as beneficial for agriculture and used as biofertilizers.
Why biofertilizers?
Biofertilizers are supposed to be a safe alternative to chemical fertilizers to minimize the ecological disturbance. Biofertilizers are cost effective, eco-friendly and when they are required in bulk can be generated at the farm itself. They increase crop yield upto 10-40% and fix nitrogen upto 40-50 Kg. The other plus point is that after using 3-4 years continuously there is no need of application of biofertilizers because parental inoculums are sufficient for growth and multiplication. They improve soil texture, pH, and other properties of soil. They produces plant growth promoting substances IAA amino acids, vitamins etc. They have 75% moisture and it could be applied to the field directly. Biofertilizers contained 3.5% - 4% nitrogen, 2% - 2.5% phosphorus and 1.5% potassium. In terms of N: P: K, it was found to be superior to farmyard manure and other type of manure (Mukhopadhyay, 2006).
Microbes used as Biofertilizer
Microbes are effective in inducing plant growth as they secrets plant growth promoters (auxins, abscisic acid, gibberellic acid, cytokinis, ethylene) and enhance seed germination and root growth. They also play a considerable role in decomposition of organic materials and enrichment of compost.
Nitrogen fixing Bacteria
1. Rhizobia: - Legumes plants have root nodules, where atmospheric nitrogen fixation is done by bacteria belonging to genera, Rhizobium, Bradyshzodium, Sinorhizobium, Azorhizobium and Mesorhizobium collectively called as rhizobia. When rhizobial culture is inoculated in field, pulse crops yield can be increased due to rhizobial symbiosis (Dubey, 2001). Rhizobium can fix 15-20 N/ha and increase crop yield upto 20%.
2. Azorhizobium: It is a stem nodule forming bacteria and fixes nitrogen symbionts of the stem nodule also produce large amount of IAA that promotes plant growth.
3. Bradyrhizobium: Bradyrhizobium is reported a good nitrogen fixer. Bradyrhizobium strain inoculation with Mucuna seeds enhances total organic carbon, N2, phosphorus and potassium in the soil, increases plant growth and consequently plant biomass, reduction in the weed population and increased soil microbial population..
These are aerobic chemolithotrophs and anaerobic photoautotrophs. These are non nodule forming bacteria. They include numbers of the families:-
1) Azotobacteracae: e.g. Azotobacter:
They are the free living aerobic, photoautotrophic, non-symbiotic bacteria. They secretes vitamin-B complex, gibberellins, napthalene, acetic acid and other substances that inhibit certain root pathogens and improves root growth and uptake of plant nutrients. It occurs in the roots of Paspalum notatum (tropical grasses) and other spp. and adds 15-93 Kg N/ha/annum on P. notatum roots (Dobereiner et al., 1973). Azotobacter indicum occurs in acidic soil in sugarcane plant roots. It can apply in cereals, millets, vegetables and flowers through seed, seedlings soil treatment.
2) Spirillaceae: e.g. Azospirillum and Herbaspirillum:
These are gram negative, free living, associative symbiotic and non-nodule forming, aerobic bacteria, occurs in the roots of dicots and monocot plants i.e. corn, sorghum, wheat etc. It is easy to culture and identify. Azospirillum is found to be very effective in increasing 10-15% yield of cereal crops and fixes N2 upto 20-40% Kg/ha. Different A. brasiliense strains inoculation in the wheat seed causes increase in seed germination, plant growth, plumule and radicle length. Herbaspirillum species occurs in roots, stems and leaves of sugarcane and rice. They produce growth promoters (IAA, Gibberillins, Cytokinins) and enhance root development and uptake of plant nutrients (N, P & K).
3) Acetobacter diazotrophicus:
Another diazotroph is Acetobacter diazotrophicus occurs in roots, stem and leaves of sugarcane and sugar beat crops as nitrogen fixer and applied through soil treatment. It also produces growth promoters e.g. IAA and helps in nutrients uptake, seed germination, and root growth. This bacterium fixes nitrogen upto 15kg /ha/year and enhance upto 0.5 – 1% crop yield (Gahukar – 2005-06).
Cyanobacteria (Blue green algae):
Nostoc, Anabaena, Oscillatoria, Aulosira, Lyngbya etc. are the prokaryotic organisms and phototropic in nature. They play an important role in enriching paddy field soil by fixing atmospheric nitrogen and supply vitamin B complex and growth promoting substance which makes the plant grow vigorously. Cyanobacteria fixes 20-30 Kg/N/ha and increase10-15% crop yield when applied at 10 Kg/ha.
Azolla – Anabaena symbiosis
It is a free floating, aquatic fern found on water surface having a cyanobacterial symbiont Anabaena azollae in their leaves. It fixes atmospheric nitrogen in paddy field and excrete organic nitrogen in water during its growth and also immediately upon trampling. Azolla contributes nitrogen, phosphorus (15-20 Kg/ha/month), potassium (20-25 kg/ha/month) and organic carbon etc. and increases 10-20% yield of paddy crops and also suppresses weed growth. Azolla also absorbs traces of potassium from irrigation water and can be used as green manure before rice planting. Azolla spp. are metal tolerant hence, can be applied near heavy metal polluted areas.
Phosphate Solubilising Bacteria
Pseudomonas fluorescens, Bacillus megatherium var. phosphaticum, Acrobacter acrogens, nitrobacter spp., Escherichia freundii, Serratia spp., Pseudomonas striata, Bacillus polymyxa are the bacteria have phosphate solubilising ability. ‘Phosphobacterin’ are the bacterial fertilizers containing cells of Bacillus megatherium var. phosphaticum, prepared firstly by USSR scientists. They increased about 10 to 20 % crop yield (Cooper, 1959) and also produces plant growth promoting hormones which helps in phosphate solubilising activity of soil.
Phosphate solubilizing fungi
Some fungi also have phosphate dissolving ability e.g. Aspergillus niger, Aspergillus awamori, Penicillium digitatum etc.
Plant Growth Promoting Rhizobacteria (PGPR)
They are also called as microbial pesticides e.g. Bacillus spp. and Pseudomonas fluorescence. Serratia spp. and Ochrobactrum spp. are able to promote growth of plants. Pseudomonas fluorescence application to the Black pepper enhanced uptake of nutrients which increased plant biomass. Fluorescent rhizobacteria improve the growth of H. brasiliensis.
Mycorrhizas are developed due to the symbiosis between some specific root inhabiting fungi and plant roots and used as biofertilizers. They absorb nutrients such as manganese, phosphorus, iron, sulphur, zinc etc. from the soil and pass it to the plant. Mycorrhizal fungus increases the yield of crops by 30-40% and also produces plant growth promoting substances.
VAM fungi or Endomycorrhiza
They occur commonly in the roots of crop plants. VAM fungal hyphae enhance the uptake of phosphorus and other nutrients that are responsible for plant growth stimulation including roots and shoot length. VAM also enhances the growth of black pepper and protects from Phytophthora capsici, Radopholus similis and Melvidogyne incognita (Anandraj et al., 2001). VAM fungi enhance water uptake in plants and also provide heavy metals tolerance to plants.