Archive

Archive for the ‘New Technology’ Category

Aeroponics:: A new technique for quality food with better plant nutient uptake

July 26, 2011 Leave a comment

Aeroponics is the process of growing plants in an air or mist environment without the use of soil or an aggregate medium (known as geoponics). The word “aeroponic” is derived from the Greek meanings of aero– (air) and ponos (labour). Aeroponic culture differs from both conventional hydroponics and in-vitro (plant tissue culture) growing. Unlike hydroponics, which uses water as a growing medium and essential minerals to sustain plant growth, aeroponics is conducted without a growing medium. Because water is used in aeroponics to transmit nutrients, it is sometimes considered a type of hydroponics.

Benefits and Limitations:Ecological advantages

Aeroponic growing is considered to be safe and ecologically friendly for producing natural, healthy plants and crops. The main ecological advantages of aeroponics are the conservation of water and energy. When compared to hydroponics, aeroponics offers lower water and energy inputs per square meter of growing area. When used commercially, aeroponics uses one-tenth of the water otherwise necessary to grow the crop.but this can be reduced to as little as one-twentieth.

Increased air exposure:: Air cultures optimize access to air for successful plant growth. Materials and devices which hold and support the aeroponic grown plants must be devoid of disease or pathogens. A distinction of a true aeroponic culture and apparatus is that it provides plant support features that are monomial. Monomial contact between a plant and support structure allows for 100% of the plant to be entirely in air. Long-term aeroponic cultivation requires the root systems to be free of constraints surrounding the stem and root systems. Physical contact is minimized so that it does not hinder natural growth and root expansion or access to pure water, air exchange and disease-free conditions.

Benefits of oxygen in the root zone

Oxygen in the rhizosphere (root zone) is necessary for healthy plant growth. As aeroponics is conducted in air combined with micro-droplets of water, almost any plant can grow to maturity in air with a plentiful supply of oxygen, water and nutrients.

Some growers favor aeroponic systems over other methods of hydroponics because the increased aeration of nutrient solution delivers more oxygen to plant roots, stimulating growth and helping to prevent pathogen formation.

Water and nutrient hydro-atomization

Aeroponic equipment involves the use of sprayers, misters, foggers, or other devices to create a fine mist of solution to deliver nutrients to plant roots. Aeroponic systems are normally closed-looped systems providing macro and micro-environments suitable to sustain a reliable, constant air culture. Numerous inventions have been developed to facilitate aeroponic spraying and misting. The key to root development in an aeroponic environment is the size of the water droplet. In commercial applications, a hydro-atomizing spray is employed to cover large areas of roots utilizing air pressure misting.

Nutrient uptake

The discrete nature of interval and duration aeroponics allows the measurement of nutrient uptake over time under varying conditions. Barak et al. used an aeroponic system for non-destructive measurement of water and ion uptake rates for cranberries (Barak, Smith et al. 1996).

In their study, these researchers found that by measuring the concentrations and volumes of input and efflux solutions, they could accurately calculate the nutrient uptake rate (which was verified by comparing the results with N-isotope measurements). After verification of their analytical method, Barak et al. went on to generate additional data specific to the cranberry, such as diurnal variation in nutrient uptake, correlation between ammonium uptake and proton efflux, and the relationship between ion concentration and uptake. Work such as this not only shows the promise of aeroponics as a research tool for nutrient uptake, but also opens up possibilities for the monitoring of plant health and optimization of crops grown in closed environments.

Categories: Agri-News, New Technology Tags:

Bt Brinjal approved for commercial use by Genetic Engineering Approval Committee (GEAC)

July 25, 2011 Leave a comment

The Genetic Engineering Approval Committee (GEAC) on 14th October gave its nod to the environmental release of Bt Brinjal, the first genetically modified food crop. With this, Bt Brinjal is expected to be commercially launched in the country despite protests from environmental groups over health issues. GEAC accepted the recommendation of a special committee, set up to study bio-safety data of Bt Brinjal. Local seed company Mahyco is developing the food crop with technology assistance from US-based multinational Monsanto. Monsanto had given the technology free to Tamil Nadu Agriculture University and the University of Agricultural Science, Dharward for commercial use after due regulatory approval. Mahyco had claimed that Bt Brijnal, which is resistant to pest and also entails far lesser use of pesticides, would be available to small farmers through public agencies. GEAC has now referred the matter to environment and forest minister Jairam Ramesh for further decision. While a GEAC official declined to comment, Ramesh later told reporters “I understand that GEAC has given approval for the environmental release of the Bt brinjal and, I will study the panel’s report before deciding whether it should be given clearance or not”. He, however, did not specify any timeframe when the decision would be taken by the government.

Rice that needs no cooking only soaking in lukewarm water is enough.

July 25, 2011 Leave a comment

Indian scientists at Central Rice Research Institute (CRRI), Cuttack, claim to have developed a rice variety that requires no cooking, only soaking in water. It is characterised by low amylase content and becomes soft on soaking in water, institute director TK Adhya said. The variety could serve specific niche consumers and make rice cooking a hassle-free affair. The new variety, named “Aghanibora”, tested by the institute is of 145 days duration with a yield of 4-4.5 tonnes per hectare and is at par with the currently grown rice varieties in the country. “One can get ready to eat rice after soaking it for about 45 minutes in ordinary water, and 15 minutes if soaked in lukewarm water, whereas other rice varieties need cooking,” Adhya said. The rice is a local improved land variety of Assam under the `Komal chawl’ category and is not GM rice. It is like any other rice variety grown and consumed in India. “However, this variety is usually prepared as parboiled rice and then it can be used for consumption after milling,” the researcher said. Scientists at the institute have done extensive research over the past three years and tested its nutritional properties and other biochemical par a meters, he said. According to the institute director, the rice variety can be grown in all the eastern states of Assam, Bihar, West Bengal, Orissa and coastal Andhra Pradesh. We do not have specific data about the average household requirement of fuel. But this variety of rice will help in saving fuel, at least for cooking of rice. Moreover, it will be a relief to housewives.

Direct Seeded Rice:: a solution to depleting water level in North India

July 21, 2011 Leave a comment

Direct Sown Rice:: New Technology for North India

Researchers from Punjab Agricultural University have initiated a multi-year project to implement and field-test diverse water-saving technologies, practices and policies aimed at reducing agricultural water use in the state of Punjab, particularly among rice farmers. The project is sponsored by the PepsiCo Foundation. In last year’s trial, the most successful project involved the installation of inexpensive tensiometers in the fields of over 500 farmers, yielding water savings of 30-35 percent.Concurrently with the tensiometer trials, the team also recruited a smaller number of farmers to adopt a different way of cultivating rice altogether: direct seeding of rice.In traditional rice cultivation, rice is sprouted in a nursery; sprouted seedlings are then transplanted into standing water. With direct seeding, rice seed is sown and sprouted directly into the field, eliminating the laborious process of planting seedlings by hand and greatly reducing the crop’s water requirements.For the CWC/PAU field project, professors Kamal Vatta and Rajinder Sidhu recruited 87 farmers to use the direct seeding approach. Initial results were mixed. Because it was an unusually wet year (30 percent higher than average) with early rainfall, seeds in 35 fields did not germinate as expected; those farmers abandoned the experiment, plowed back their fields and planted rice the traditional way.However, results from the 52 farms that remained were promising; each farm saving substantial amounts of water with no negative impact on yield. According to Professor Sidhu, water savings are at least as great as those achieved by the use of the tensiometer. Direct seeding of rice is not a new idea; a number of farmers throughout Asia have cultivated the crop this way for decades. Perhaps most famously, beginning in the 1950s Masanobu Fukuoka, the Japanese farmer-philosopher and author of The One Straw Revolution, flouted both traditional Japanese rice cultivation and industrial production models by seeding rice directly and keeping fields dry for most of the season. Fukuoka’s method involved an elaborate system of groundcovers and crop rotation to minimize competition from weeds.As usually practiced, however, weed control is a serious challenge for the direct seeding approach. Weeds are one of the main reasons rice is traditionally sprouted in nurseries and transplanted; standing water prevents germination of competing plants. According to Professor Sidhu, researchers at the Punjab Agricultural University experimented with the direct seeding approach years ago but abandoned it when results showed that “the infestation of weeds is so high that it significantly reduces yield; therefore it was dropped from the research agenda.” At the time, he says, University research focused almost exclusively on “maximizing productivity in relation to water use, rather than optimizing productivity in relation to water use.” It wasn’t until the 1990s, when awareness of a looming water crisis began to grow, that PAU researchers began to look more seriously at the water issue. In the end though, it was field experience from a number of progressive farmers in Punjab who had taken up direct seeding on their own that spurred the University to begin a new round of experiments. The farmers claimed that they were successfully using direct seeding to grow rice, with no negative impact on yield. Around the same time, says Sidhu, a new generation of weedicides appeared on the market, allowing for a very effective suppression of weeds without standing water. Positive results from the PAU’s own research led the University to issue a temporary recommendation to farmers for direct seeding, pending further field tests.
What is the downside? According to Sidhu, compared to using tensiometers, farmers were less enthusiastic about direct seeding, probably because it requires a completely different method of cultivation over conventional practices, and germination failure can also be an issue. On the other hand, direct seeding of rice—especially if using weedicdes—is substantially more labor-efficient than conventional rice planting. Given the emerging issue of serious labor-shortages in the state of Punjab, techniques like direct-seeding could become much more popular fast. And what about concern over increased use of weedicides? Sidhu says that we don’t know if there will be negative consequences from the weedicides used on direct-seeded fields. But given the emerging concern in Punjab and elsewhere over rising rates of cancer and ecological damage, it would seem to be an issue to take seriously.
Retired professor SS Johl, a long time luminary in the world of Punjab agricultural research, believes that it is possible to use direct-seeded cultivation without application of weedicides—if one has the labor. He points out that with direct seeding of rice, the labor saved upfront on transplanting can be applied later to weeding. “If you have the labor,” he says, “you should not apply weedicide.”