Crop and water productivity as influenced by rice cultivation methods under organic and inorganic sources of nutrient supply
Author by Y.V. Singh, Centre for Conservation and Utilization of Blue Green Algae (CCUBGA), Indian Agricultural Research Institute, New Delhi – 110 012, India, Email: email@example.com; firstname.lastname@example.org
Source: Paddy and Water Environment [http://www.springerlink.com/
Publication Date: 28 August 2012
A field experiment was conducted during the wet seasons of 2010 and 2011 at New Delhi, India to study the influence of organic, inorganic, and integrated sources of nutrient supply under three methods of rice cultivation on rice yield and water productivity. The experiments were laid out in FRBD with nine treatment combinations. Treatment combinations included three sources of nutrient supply viz., organic, integrated nutrient management, and inorganic nutrition and three rice production systems viz., conventional transplanting, system of rice intensification (SRI) and aerobic rice system. indicated that the conventional and SRI showed at par grain and straw yields but their yields were significantly higher than aerobic rice. Grain yield under organic, inorganic and integrated sources of nutrient supply was at par since the base nutrient dose was same. Plant growth parameters like plant height, tillers, and dry matter accumulation at harvest stage were almost same under conventional and SRI but superior than aerobic rice system. Root knot nematode infestation was significantly higher in aerobic rice as compared to SRI and conventional rice. However, organic, inorganic and integrated sources of nutrient supply did not affect nematode infestation. There was significant advantage in term of water productivity under SRI over conventional transplanted (CT) rice and less quantity of water was utilized in SRI for production of each unit of grain. A water saving of 34.5–36.0 % in SRI and 28.9–32.1 % in aerobic rice was recorded as compared to CT rice.
Partitioning of CH4 and CO2 production originating from rice straw, soil and root organic carbon in rice microcosms
Author(s): Quan Yuan, Judith Pump, Ralf Conrad
Source: PLoS ONE | November 5, 2012
Flooded rice fields are an important source of the greenhouse gas CH4. Possible carbon sources for CH4 and CO2 production in rice fields are soil organic matter (SOM), root organic carbon (ROC) and rice straw (RS), but partitioning of the flux between the different carbon sources is difficult. We conducted greenhouse experiments using soil microcosms planted with rice.
download an interesting book let on Rice in India covering the impacts of hybrid rice in eastern India, potentials of some traditional lines of paddy.
Washington: Scientists have found that the glycemic index (GI) of rice varies a lot from one type of rice to another, with most varieties scoring a low to medium GI.
And they have revealed that rice varieties such as India’s most widely grown rice variety, Swarna, have a low GI.
The findings of the research, which analyzed 235 types of rice from around the world, is good news because it not only means rice can be part of a healthy diet for the average consumer, but it also means people with diabetes, or at risk of diabetes, can select the right rice to help maintain a healthy, low-GI diet.
The study found that the GI of rice ranges from a low of 48 to a high of 92, with an average of 64.
The research team from the International Rice Research Institute (IRRI) and Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) Food Futures Flagship also identified the key gene that determines the GI of rice, an important achievement that offers rice breeders the opportunity to develop varieties with different GI levels to meet consumer needs.
Future development of low-GI rice would also enable food manufacturers to develop new, low-GI food products based on rice.
Dr. Melissa Fitzgerald, who led the IRRI team, said that GI is a measure of the relative ability of carbohydrates in foods to raise blood sugar levels after eating.
“Understanding that different types of rice have different GI values allows rice consumers to make informed choices about the sort of rice they want to eat,” she said.
“Rice varieties such as India’s most widely grown rice variety, Swarna, have a low GI and varieties such as Doongara from Australia and Basmati have a medium GI,” Dr. Fitzgerald noted.
Dr. Tony Bird, CSIRO Food Futures Flagship researcher, said that low-GI diets offer a range of health benefits: “Low-GI diets can reduce the likelihood of developing type 2 diabetes, and are also useful for helping diabetics better manage their condition.
“This is good news for diabetics and people at risk of diabetes who are trying to control their condition through diet, as it means they can select the right rice to help maintain a healthy, low-GI diet,” he added.
Low-GI foods are those measured 55 and less, medium-GI foods are those measured between 56 and 69, while high-GI foods measure 70 and above.
When food is measured to have a high GI, it means it is easily digested and absorbed by the body, which often results in fluctuations in blood sugar levels that can increase the chances of getting diabetes, and make management of type 2 diabetes difficult.
Conversely, foods with low GI are those that have slow digestion and absorption rates in the body, causing a gradual and sustained release of sugar into the blood, which has been proven beneficial to health, including reducing the chances of developing diabetes.
Eating rice with other foods can help reduce the overall GI of a meal and, when combined with regular exercise, can reduce the chances of getting diabetes. In addition, people who exercise need more carbohydrates in their diet and can take advantage of low-GI foods for sustained activity.
Rice plays a strong role in global food security. Being the staple for about 3.5 billion people, it is important to maximize the nutritional value of rice. Low-GI rice will have a particularly important role in the diets of people who derive the bulk of their calories from rice and who cannot afford to eat rice with other foods to help keep the GI of their diet low. Low-GI rice could help to keep diabetes at bay in these communities.
This is the first of several studies the group plans to carry out based on investigating the role of rice in mitigating chronic diseases such as type 2 diabetes.
By Sreedevi Lakshmi Kutty, ENS – THIRUVANANTHAPURAM
04th July 2012 11:11 AM
Recently, studies have established that the causative link to diabetes is with “polished white rice” not any rice. It is increasingly being established that unpolished red and brown rice do not cause diabetes.
Rice is my soul food, what I long for when I am hungry and what I miss when I don’t get it. Belonging to the post-green revolution generation, white rice came into our family pretty early despite living in the land of red rice, Kerala.
When we were young, my great grandmother who cultivated our ancestral paddy lands used to send us unpolished parboiled red rice. When she became bedridden the lands were left fallow, eventually sold, and the money used to buy a then much-coveted refrigerator, prompting my mother to say, “we sold our rice-growing lands to buy an ice-box to store stale-cooked rice!”
I lived in different cities in India and abroad and bought polished white rice. I was concerned about the quality and price, beyond that I didn’t think it mattered. Moving to Mumbai, I found that the south Indian stores provided red rice; sadly, this was red only in name and appearance. The colour washed off like from a bad fabric!
It was at this juncture, as part of my work with agriculture and food issues, I got involved with the ‘Save Our Rice’ campaign. It was at this time that the spread of diabetes in India, particularly in the south, began to be associated with the consumption of rice.
Recently, studies have established that the causative link to diabetes is with “polished white rice” not any rice. It is increasingly being established that unpolished red and brown rice do not cause diabetes. In fact, red rice is known to have many beneficial health effects and is also nutritionally superior.
Watching and sharing the dilemma of the farmers, I realised that we as consumers have a role in reviving rice.
To save agro-biodiversity, we have to eat diverse foods, thereby promoting their cultivation and propagation -that is exactly how rice consumers will become rice savers!
We, in India, are rich in rice heritage and had till about 40 years back over 1,10,000 varieties of rice; now we are down to about 6,000 varieties, according to Dr Debal Deb, one of the foremost rice savers in India.
Why do we need this diversity? We need it to keep the robustness of the crop and diversity aids the evolution of stronger and more adaptable varieties.
And how do we protect this diversity? Simply by growing and eating. The more varieties of rice we all eat, greater the range of varieties farmers will grow season after season.
During the last few years I have eaten various kinds of red rice – raw and par boiled with full bran or partly removed, the fragrant ‘Gandhakasala’ from Wayanad, the smell of which tempted my aged and ill father to eat rice after many days, ‘Mullankazhama’ – a lovely flower-like rice which makes delicious ‘payasam’ and the small grained brown rice called ‘Komal’, cultivated by Susheel an organic farmer and a good friend.
I have also come across other rice varieties like the ‘Rajamudi’ rice used by the Wadiyars of Mysore, the fascinating variety named ‘Thavalakannan’ (literally means frog’s eyes) which is favoured by temples in Kerala for preparing beaten rice flakes and ‘Njavara’ rice that is recommended for diabetics. There are rice varieties that are good for lactating women and numerous rices with medicinal properties as well.
Why don’t we unearth some of the indigenous rices we have and their uses and find innovative ways to cook them for our families? In Karnataka, farmers are conserving around 140 varieties of rice, in Tamil Nadu, around 40 varieties are distributed every year through a seed mela, groups in Wayanad are trying to conserve traditional varieties used by the tribals, even in Thane, Mumbai, over a hundred varieties of rice are being conserved.
‘Natabara Sarangi’, a rice saver in Orissa, conserves 310 varieties. But, we need more rice savers who relish traditional rice, to conserve the most valuable grain known to mankind.
(The author works with groups promoting safe food, urban farming and sustainable agriculture and currently lives in The Hague, Netherlands)