Effect of farm management practices in the Bt toxin production by Bt cotton: evidence from farm fields in China.

Based on farm field plot level survey data and laboratory test, we examine the determinants of the expression of Bt toxin in China's Bt cotton production. The results show that the expression of Bt toxin differs significantly among varieties. Even for the same variety the expression of Bt toxin also varies substantially among villages and among farmers in the same village. Econometric analyses show that after controlling for the effects of varieties and locations (or villages), farm management, particular applications of phosphate and potash fertilizers, and manure, has significant positive effects on Bt toxin expression in farmer's fields. In contrast to previous studies which showed that nitrogen fertilizer has a positive impact on expression of Bt toxin, this study shows that nitrogen fertilizer has no significant impact on expression of Bt toxin in farmer's fields. On the other hand, the expression of Bt toxin has a positive relationship with phosphate fertilizer, potash fertilizer and manure application.

Managers' attitudes toward gene-editing technology and companies' R&D investment in gene-editing: the case of Chinese seed companies.

The Chinese government has issued a series of new policies to make it easier to industrialize gene-edited crops. However, whether technological advantages will eventually translate into industrial advantages and whether farmers will soon have access to gene-edited varieties partly depends on seed companies' willingness to produce and sell gene-edited varieties to farmers and to invest in developing their own gene-edited varieties. This study utilizes data from a survey of 111 seed companies collected in 2019 before the implementation of new regulations. This study provides empirical evidence on whether gene-edited crops will be available to farmers. The results show that the number of companies conducting research on gene-edited crops is limited, mostly to large companies. Approximately 55% of seed company managers would consider developing and selling gene-edited crops modified by SDN-1 and SDN-2 site-directed nuclease genome editing without external genetic material, whereas 46% support crops modified by SDN-3, which require gene replacement or foreign deoxyribonucleic acid (DNA) insertion and are regulated as genetically modified organisms (GMOs). The regression results show that large companies and companies with well-educated researchers are more likely to support and develop gene-editing technology. Past GM investment experience and collaboration with public institutions in gene-editing research increases the probability of company investment in gene editing R&D. These results suggest that gene-edited cultivars are more likely to be produced and sold to farmers in the future than GMOs, and that gene-edited agricultural products could have a significant market share of the seed market in the future.

Governmental regulation induced pesticide retailers to provide more accurate advice on pesticide use to farmers in China.

BACKGROUND: In China, pesticide retailers have often been accused of providing inaccurate advice on pesticide use to farmers in a chaotic pesticide market. However, it is unclear whether governmental regulation of sales and advice on pesticide use by pesticide retailers induces them to provide accurate advice. RESULTS: Using survey data of 242 pesticide retailers in 2016, this study analyzes how pesticide retailers in China provide advice on pesticide use to farmers and examines whether governmental regulation induces pesticide retailers to provide accurate advice. The surveyed retailers were found to advise farmers to use the correct active ingredients in only 75.6% of observations. Retailers recommended pesticide application rates higher than the scientifically recommended levels among 57.2% of observations. The bivariate probit model estimation results show that highly intensive governmental regulation increases the probability of correct advice on pesticide use of pesticide retailers in the county and township seats by 13% and 19%, respectively. Moreover, highly intensive regulation can also increase the probability of pesticide non-overuse advice by the retailers from the retailers in the villages by 38%. CONCLUSION: Highly intensive governmental regulation can induce pesticide retailers to provide more accurate advice on pesticide use to farmers, but the effects differ across the locations of pesticide retailers. © 2021 Society of Chemical Industry.

The Chinese public's awareness and attitudes toward genetically modified foods with different labeling.

This paper analyzes the awareness and attitudes of the Chinese public toward genetically modified (GM) foods with different types of labeling and evaluates the impact of public confidence in the government management of GM food labeling has on their attitude. From 2015 to 2016, we conducted a series of surveys to collect data from 1730 respondents, which included consumers, farmers, media, and local agricultural officials in agricultural departments. The results show ~60% of the Chinese public do not know that they usually consume or purchase GM products or products containing GM ingredients. Nearly 80% of the Chinese public are accepting foods labeled as not containing GM ingredients, 57% are accepting foods without labeling, and ~40% are accepting GM-labeled foods. The respondents with a lack of confidence in the government are less likely to embrace GM foods. Those that are more aware of GM products are more likely to accept GM labeled foods. The group having the most positive attitude toward GM-labeled foods is the media, followed by agricultural officials, while the group having the most negative attitude toward GM labeled foods is farmers. Our findings provide an empirical basis to inform GM food labeling policy discussions and possible revisions, which may promote the development of GM foods in China.

Do farmers misuse pesticides in crop production in China? Evidence from a farm household survey.

BACKGROUND: In China, pesticide overuse and underuse have been studied. However, little empirical evidence has been provided for pesticide misuse. RESULTS: Using data from a farm household survey in 2016, we quantitatively analyzed Chinese farmers' pesticide misuse in the production of rice, apple, tea, and greenhouse vegetables. The results show that pesticide misuse is common in China. However, the misuse is found to be lower in rice production than in the production of apple, tea, and greenhouse vegetables. Compared with that of the major pests, pesticide misuse is much more common for the control of the secondary pests. In a considerable number of observations, some farmers even failed to indicate the pests they controlled or the pesticides they used. CONCLUSIONS: Pesticide misuse may result in both the overuse and underuse of pesticides. In China, pesticide misuse could be attributed to the lack of pest management knowledge among farmers, limited accessibility to a high-quality governmental agricultural extension service, misleading information, and absence of pest prediction and forecast. Hence, a socialized agricultural extension system and new agricultural extension models adapted to different farmers are expected to be developed and implemented in China. © 2019 Society of Chemical Industry.

A comparison of the effects of agricultural pesticide uses on peripheral nerve conduction in China.

Evidence on the adverse effects of agricultural pesticide use by farmers under the actual field conditions on their peripheral nerve conduction in China is limited. This study was to investigate the association of agricultural pesticide use with the abnormalities of farmers' peripheral nerve conduction based on two rounds of conventional nerve conduction studies. The level of pesticide exposure was assessed by measuring total amount of pesticides used by farmers in 2012. The logistic and negative binomial regression analyses were performed on a cohort study of 218 farmers. Results show that agricultural use of neither glyphosate nor non-glyphosate herbicides was not found to induce the abnormalities of farmers' peripheral nerve conduction. However, agricultural use of organophosphorus compounds was significantly associated with increased risk of demylination disease of peripheral nerve conduction described by the reduced velocity. Moreover, the use of organonitrogen compounds by farmers would not only increase risk of demylination disease but axonal damages described by the reduced amplitude. By contrast, agricultural uses of organosulfur and pyrethroid compounds would not induce the abnormalities of farmers' peripheral nerve conduction. The findings demonstrated the importance of developing health-friendly pesticides to replace organophosphorus and organonitrogen insecticides and fungicides in China.

Health effect of agricultural pesticide use in China: implications for the development of GM crops.

It is notable that the adoption of GM glyphosate-tolerant crops increases glyphosate use but reduces non-glyphosate herbicide use; and adoption of GM insect-resistant crops significantly reduces insecticide use. While the health hazard of pesticide use has been well documented, little literature evaluates the health effects of different pesticides related to GM crops in an integrated framework. This study aims to associate the uses of different pesticides related to GM crops with the blood chemistry panel and peripheral nerve conduction of Chinese farmers. Pesticides used by farmers were recorded and classified as glyphosate, non-glyphosate herbicides, chemical lepidopteran insecticides, biological lepidopteran insecticides, non-lepidopteran insecticides and fungicides. The multivariate regression results show that none of the examined 35 health indicators was associated with glyphosate use, while the use of non-glyphosate herbicides was likely to induce renal dysfunction and decrease of serum folic acid. The use of chemical lepidopteran insecticides might be associated with hepatic dysfunction, serum glucose elevation, inflammation and even severe nerve damage. In this context, if GM crops are adopted, the alterations in pesticide use may benefit farmer health in China and globe, which has positive implications for the development of GM crops.

Association between occupational exposures to pesticides with heterogeneous chemical structures and farmer health in China.

This study analyzed the associations of farmers' exposure to organophosphates (OPs), organosulfurs (OSs), organonitrogens (ONs) and pyrethroids (PYRs) with parameters of the blood complete counts (CBC), a blood chemistry panel (BCP) and the conventional nerve conduction studies among 224 farmers in China in 2012. Two health examinations and a series of follow-up field surveys were conducted. Multiple linear regression analyses were used to evaluate the associations. The results show considerable associations between multiple groups of pesticides and several CBC parameters, but it was not enough to provide evidence of hematological disorders. The short- and medium-term OPs exposures were mainly associated with liver damage and peripheral nerve impairment, respectively, while OSs exposure might induce liver damage and renal dysfunction. The neurotoxicity of ONs was second only to OPs in addition to its potential liver damage and the induced alterations in glucose. In comparison, the estimated results show that PYRs would be the least toxic in terms of the low-dose application. In conclusion, occupational exposures to pesticides with heterogeneous chemical structures are associated with farmer health in different patterns, and the association between a specific group of pesticides and farmer health also differs between the short- and medium-term exposures.

Overuse or underuse? An observation of pesticide use in China.

Pesticide use has experienced a dramatic increase worldwide, especially in China, where a wide variety of pesticides are used in large amounts by farmers to control crop pests. While Chinese farmers are often criticized for pesticide overuse, this study shows the coexistence of overuse and underuse of pesticide based on the survey data of pesticide use in rice, cotton, maize, and wheat production in three provinces in China. A novel index amount approach is proposed to convert the amount of multiple pesticides used to control the same pest into an index amount of a referenced pesticide. We compare the summed index amount with the recommended dosage range of the referenced pesticide to classify whether pesticides are overused or underused. Using this new approach, the following main results were obtained. Pesticide overuse and underuse coexist after examining a total of 107 pesticides used to control up to 54 crop pests in rice, cotton, maize, and wheat production. In particular, pesticide overuse in more than half of the total cases for 9 crop pest species is detected. In contrast, pesticide underuse accounts for more than 20% of the total cases for 11 pests. We further indicate that the lack of knowledge and information on pesticide use and pest control among Chinese farmers may cause the coexistence of pesticide overuse and underuse. Our analysis provides indirect evidence that the commercialized agricultural extension system in China probably contributes to the coexistence of overuse and underuse. To improve pesticide use, it is urgent to reestablish the monitoring and forecasting system regarding pest control in China.