Some rice lines are genetically modified with the crystal toxin genes from Bacillus thuringiensis, which is also referred to as BT. They have experienced rapid development, with biosafety certificates for two BT rice lines issued in 2009. This is known as BT rice.
Research has shown that gene confers resistance to various pests, including the rice borer, through endotoxins production. A study titled Transgenic Bacillus thuringiensis (BT) Rice Is Safer to Aquatic Ecosystems than Its Non-Transgenic Counterpart reveals there has been no commercial release of these lines yet due to public worries and concerns regarding the human health and environmental risks.
However, they also show evidence that BT rice was as safe as conventional rice to non-target organisms when pesticides were not applied. But pesticides are still required in BT rice to control non-lepidopteran pests.
Environmental effects of two BT rice lines expressing were studied. They used either the cry1Ab/1Ac or cry2A genes, respectively, by using zooplanktons as indicator species under normal field management practices using pesticides when required.
Through this complete growing season, non-BT rice was sprayed 5 times while BT rice was sprayed 2 times. Both of the rice types achieved a normal yield. Rice type (BT and non-BT) had a drastic impact on zooplankton abundance and diversity, which were up to 95% and 80% lower in non-BT rice fields than BT rice fields.
Impact of water
Also, further research in this genre also shows that water from non-BT rice fields was significantly less suitable for the survival and reproduction of Daphnia Magna and Paramecium caudatum in comparison with water from BT rice fields.
In contrast to BT rice, the water residues from non-BT than BT rice fields were higher. These account for the poor performance of zooplankton in non-BT field water. With all of this information, it can be stated that BT rice is safer to aquatic ecosystems than non-BT rice, and its commercialization will be beneficial for biodiversity restoration in rice-based ecosystems.
Climate change & BT rice
Considering the growing world population, rice production is likely to be impacted by climate change. There are also many other associated risks, including pest complexes and consumption of chemical inputs. These highlight risks of decreasing production at a regional scale and one of the major global concerns.
There are a lot of biotic stresses that can damage the crop. It includes the risk of insect pests, which can be categorized as either minor or major pests, severely constraining rice's potential yield. Considering these risks, planting transgenic rice is considered a solution for reducing environmental and human health impacts.
Health impacts of transgenic and non-transgenic
The above-mentioned study on transgenic rice evaluated the life cycle assessment for environmental and human health impacts of transgenic and non-transgenic rice cultivars. Four transgenic lines (driven from back cross of Khazar cultivar with transgenic line of Tarom Molaii). Along with this, conventional cultivars (non-transgenic parents) were cultivated as per the norms of biosafety protocol in three isolated sites in the north of Iran in 2016.
The life cycle assessment was done first. All of the results were analyzed separately. There wasn't much difference between the impact categories and indices in different sites. However, the research does reveal decreased insecticide application in transgenic cultivars lowers the need for labor, machinery, and fuel. Overall, this is a contributing factor for reducing the use of energy and greenhouse gas emissions from construction, transportation, and application of inputs during cultivation.
A PubMed study was done to investigate the potential unintended effects of TT51 on the reproductive system in male rats. The rates under observation were given diets containing 60% of either TT51 or MingHui63 by weight, nutritionally balanced to an AIN93G diet, for 90days. On the other side, a controlled negative control group of rats was fed with a rice-based AIN93G diet.
During this study, the body weights, food intake, hematology, serum chemistry, serum hormone levels, sperm parameters, and relative organ/body weights were measured. Alongside, the microscopic pathology was examined. Based on the studies, it was revealed that there were no diet-related significant differences in the values of response variables were observed between rats that were fed with diet containing transgenic TT51, MingHui63, and the control in this 90-day feeding study.
The test also showed no treatment-related changes. So while there may not be much of an impact on nutrition, BT rice is safer and healthier for the environment.
In India, many of the prominent rice companies have put a foothold across the market with various BT rice in Kolam Rice forms. The manufacturing and supplying are concerned about offering the highest quality assured and new range. Stocks are procured from farmers keeping in mind the grades and norms of the food industry. The rice offers nutrition and rich fiber.