Channel: Special Thesis & Basic Research http://www.zgdm.net EN-US http://www.zgdm.net/EN/1006-8082/current.shtml http://www.zgdm.net 1006-8082 http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.001 In 2023, the total production of rice in China has been kept at over 200 million tons for 13 consecutive years with the area decreased slightly, and the yield has reached a new record high. The price of rice in the domestic market kept relatively strong, and the rice consumption is basically stable. Rice imports fell sharply and exports continued to decline. The quality level has been continuously improved, but the number of varieties approved decreased. The mode of operation has been continuously optimized, and the promotion of social services, green, efficient, light and simplified technologies and intelligent technologies has been accelerated. Facing problems of rice industry in China were analysed. It is projected that there is going to keep stable in rice area and the yield will increase slightly in 2024, and the rice market will run smoothly, the high-quality rice will develop rapidly.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.003 Pseudomonas mosselii JP2-207 was isolated from the soil of the rhizosphere of rice plants, this strain showed obvious inhibitory activity against Ustilaginoidea virens, an important rice pathogen. The complete genome of P. mosselii JP2-207 consists of 5 702 443 bp with a circle chromosome, 5 154 protein-coding genes, 22 rRNA genes, and 78 tRNA. The genomic analysis revealed that 9 candidate gene clusters were involved in the biosynthesis of secondary metabolites. Together, this study provides preliminary results for exploring the antagonistic mechanism of rice false smut by P. mosselii JP2-207 and its secondary metabolites.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.004 A pot experiment was conducted by adding multiple composite regulators to selenium-rich soil, in order to clarify the effects of different endogenous selenium regulators on the absorption of selenium (Se), cadmium (Cd), arsenic (As) by rice and the forms of Se, Cd, and As in soil. The results showed that, the application of 1% or 2% montmorillonite composite conditioner (MT) could achieve the effects of increasing selenium and reducing cadmium in rice, with a 2% addition rate having the best effect. Under the condition of high selenium soil (soil Se content of 1.99 mg/kg), applying calcium magnesium phosphate fertilizer + phosphate rock powder + active silicon (GLG) could achieve dual effects of excessive Se reduction and simultaneous As reduction in rice. Under the condition of medium selenium soil (soil Se content of 0.83 mg/kg), adding calcium magnesium phosphate fertilizer + bone powder + active silicon (GGG) had the best effect on increasing selenium and reducing arsenic in rice. However, under the condition of low selenium soil (soil Se content of 0.46-0.47 mg/kg), adding calcium magnesium phosphate fertilizer+ biochar + organic bacterial fertilizer + activated silicon (GTJG) and calcium magnesium phosphate fertilizer + lime+ activated silicon had better effect.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.005 A split plot experimental design was used to explore the effects of different nitrogen fertilizer management methods on the growth and development, yield, and nitrogen fertilizer utilization efficiency of ordered mechanical throwing late rice Jiayouchangjin. The main plot is the nitrogen application rate (N), with three levels set, namely 120 kg/hm² (N1), 150 kg/hm² (N2), and 180 kg/hm² (N3). The sub plot is the distribution ratio of nitrogen fertilizer (base fertilizer: tillering fertilizer: spike fertilizer), with four levels set, namely 1:1:1 (T1), 0:1:1 (T2), 1: 0:1 (T3), and 1:1:0 (T4). Using farmers' habitual fertilization as a control (CK, nitrogen fertilizer dosage of 120 kg/hm2, base fertilizer: tillering fertilizer: ear fertilizer=5:3:2), and another non nitrogen treatment as control 2(N0). The results showed that under the same nitrogen application rate, the rice yield of T2 treatment was significantly lower than that of T1, T3, T4 treatment and CK, the rice yield of T4 treatment was higher than that of T1 treatment and CK. It can be seen that the application of basic fertilizers helps to improve the yield of ordered mechanical throwing late rice. In terms of nitrogen fertilizer utilization, the nitrogen fertilizer utilization rate of T2 treatment was significantly lower than that of other treatments. The differences in nitrogen partial productivity (NPFP), nitrogen grain production efficiency (NUEg), nitrogen physiological utilization efficiency (NPE), and nitrogen harvest index (NHI) among T1, T3, T4 treatments and CK were relatively small. The above results indicated that the application of nitrogen fertilizer in the early stage had a significant regulatory effect on the growth and development, yield formation, and nitrogen utilization of ordered machine thrown late rice, while the effect of nitrogen fertilizer application in the later stage was relatively small.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.006 A field experiment was carried out in tidal flat of Jiangsu Province (the salt content in the soil is 1.11-1.26 g/kg) in 2021 to study the effects of different exogenous substances and spraying periods (2 times: tillering stage, booting stage and 3 times: tillering stage, booting stage, filling stage) on the panicle traits, yield and quality of rice, taking Nanjing 5055 as the test variety. Seven treatments were set up in the experiment, including spraying clean water (CK), spraying Hejiachun twice (L1-2), spraying Bihu twice (L2-2), spraying Naphthoacetic twice (L3-2), spraying Hejiachun three times (L1-3), spraying Bihu three times (L2-3), and spraying Naphthylacetic three times (L3-3). The results showed that spraying exogenous substances had the effect of improving rice yield. Compared with CK (the rice yield was 7 310.3 kg/hm²), L2-2, L2-3, L3-2, and L3-3 significantly increased rice yields by 17.69%, 17.80%, 11.62%, and 13.42%, while L1-2 and L1-3 increased rice yields by 6.66% and 7.09%, respectively, but the difference was not significant. However, spraying treatments had little effect on quality of rice. Spraying exogenous substances did not significantly affect the effective panicle number and seed setting rate of rice, but significantly increased the number of solid grains. L1-2, L2-2, L1-3 and L3-3 treatments significantly increased the number of grains per spike, while L2-2 and L2-3 treatments significantly increased the weight of 1 000 grains. Spraying exogenous substances did not significantly affect the number of branches, total number of grains, number of solid grains and seed setting rate of primary branches and stems of rice, but increased the number of branches, total number of grains, number of solid grains and seed setting rate of secondary branches of rice, and the contribution rate of secondary branches to grain number per panicle has generally increased. For the same exogenous substance, there was no significant difference in the effects of spraying twice and spraying three times on rice yield and panicle traits. The increase of rice yield under Bihu spraying treatment was mainly caused by the increase of grain number per panicle, solid grain number per panicle and 1000-grain weight. The increase of grain number per panicle under Naphthoacetic spraying treatment was mainly caused by the increase of grain number per panicle and solid grain number per panicle, and the increase of grain number per panicle was mainly related to the increase of the number of secondary branches, the total number of grains and solid grain number of secondary branches. Therefore, when planting rice in the tidal flat in the future, we can improve the spike grain structure, especially the secondary branch characters, by spraying exogenous foliar fertilizer or plant growth regulators at the tillering stage and booting stage, so as to increase rice yield and income.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.007 A field experiment was conducted in typical cadmium polluted farmland in Quzhou, Zhejiang, with Chunyou 84 and Zhongzheyou 8 as experimental materials, to study the effects of organic fertilizer and soil conditioner on pH and available state of heavy metal elements (Cd, Fe, Mn, Zn, etc.) in soil, and accumulation of heavy metal elements in rice plants (straw, grains), and their mechanism of reducing grain Cd accumulation. The results showed that single application of organic fertilizer (1.5 t/hm²) had no significant effect on the effective state of heavy metal elements in soil and the content of heavy metal elements in rice straw and grains. However, under the combined application of organic fertilizer (1.5 t/hm²) and soil conditioner (2.7 t/hm²), the soil pH increased, but the available state of heavy metals in the soil and the content of heavy metals in rice plants showed a downward trend. The available Cd content in soil decreased by 16.41% (DTPA extraction) and 48.96% (CaCl₂ extraction), while the Cd content in rice straw and grains decreased by 40.04% and 48.22%, respectively. Stepwise regression and path analysis showed that the Cd content in rice straw and Cd availability in soil were significantly correlated with Cd content in grains. It can be seen that the application of soil conditioners reduces the available content of heavy metal elements in soil by increasing soil pH, with a particularly significant decrease in available Cd content, thereby regulating the accumulation of Cd in rice straw and grains. Therefore, it indicates that the tested soil conditioner can be promoted and applied in acidic soil areas, with the effect of increasing the pH of acidic soil and reducing the enrichment of Cd in rice.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.008 A potted experiment was conducted to explore the differences in rice quality between the main rice and ratoon rice by setting the same temperature, using the indica-japonica hybrid rice Yongyou 4149 as the research material. The results showed that under high temperature condition, the brown rice percentage, milled rice percentage, head milled rice percentage, grain length, chalky rice rate, chalkiness degree, and amylose content of ratoon season rice were significantly higher than those of the main season rice. There was no significant difference in gel consistency between the two season rice. Under the suitable temperature condition, the milled rice percentage, head milled percentage and grain length of ratoon season rice were significantly higher than those of the main season rice. There was no significant difference in brown rice percentage, chalky rice rate, chalkiness degree, amylose content and gel consistency between the two season rice. The crude protein content in ratoon season rice were significantly lower than those in the main season rice under high temperature and suitable temperature conditions. Therefore, under the same conditions, compared with the main season rice, the milled rice quality and cooking taste quality of the ratoon season rice are better, but the nutritional quality is reduced.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.009 Rice-fishing symbiosis is a new type of agricultural model that uses paddy wetland ecosystems to breed aquatic products in traditional paddy fields to achieve co-operation or rotation of rice and aquatic products. This model utilizes the mutually beneficial symbiosis between rice and aquatic products to reduce field pollution, reduce pests and diseases, and improve the material conversion efficiency of farmland ecosystems. In order to analyze the effects of rice-fishing symbiosis model on the quality of aquatic products and intestinal microorganisms, and promote the scientific development of rice-fishing comprehensive breeding, we discussed the nutrition, muscle quality and intestinal microorganisms of aquatic products, and laid a theoretical foundation for the high-quality sustainable development of rice-fishing comprehensive breeding industry.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.002 A split experiment of two-factor was conducted to explore the best measured leaf position of the SPAD value of rice leaves, the best secondary index of SPAD value, and build a nitrogen (N) nutrition diagnosis model based on the SPAD value of rice leaves. The main plots consisted of variety treatment (two variety: Qyou 6 and Yixiangyou 2115) and the subplots consisted of the N application rate (five N levels: 0, 75, 150, 225, 300 kg/hm²). The sensitivity, representativeness, and stability of rice leaves were analyzed. The relationship between SPAD value index and N application rate and leaf N content (LNC), and the relationship between leaf N accumulation (LNA) and LNC and yield were studied. The results showed that the sensitivity, representativeness and stability of rice leaf in order of magnitude were L4 > L3 > L1 > L2, L3 > L4 > L2 > L1, L2 > L3 > L4 > L1, respectively. Thus, L3 and L4 can be used as the common ideal indicator leaves for N nutrition diagnosis. The geometric mean of SPAD value of the top 3 and 4 leaves of rice plant (GMSI34) was selected as the best secondary index of SPAD value. According to the parabola equation of LNA and yield, univariate linear regression equation of LNA and LNC, and the exponential equation of GMSI34 and LNC, the critical values of SPAD value secondary index (GMSI34_cri) at jointing stage, booting stage, and heading stage are 48.5, 44.3, and 42.9, respectively. Compared with the actual GMSI34 (GMSI34_act), if GMSI34_act < GMSI34_cri, it indicates that rice lacks nitrogen and needs nitrogen topdressing, if GMSI34_act ≥ GMSI34_cri, it shows that the rice has sufficient nitrogen nutrition and does not need nitrogen topdressing. In conclusion, the N nutrition diagnosis model based on the SPAD value of hybrid rice leaves can provide technical support for efficient N fertilizer management of hybrid rice.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.010 We analyzed the applications and authorizations of new rice variety protection in China from 1999 to 2022, expounded the development status of new rice variety protection and DUS testing in China, analyzed the existing problems in the industry, and proposed the countermeasures and suggestions for strengthening the protection of new rice varieties and optimizing DUS testing, in order to provide beneficial reference for the protection of new rice varieties and the standardization of DUS testing in the new era in China.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.011 To accurately evaluate the stability and adaptability of rice varieties, we analyzed the yield data of 14 participating varieties from six mid-early experiment sites of Liaoning Province using GGE-biplot in 2019. The results showed that genotype, environment and interaction between genotype and environment influenced rice yield very significantly. The six pilot areas can be divided into three ecological types, and Yuanjing 2 performed the best in its respective ecological areas. Meifengdao 245, Jingyuan 2, and Fuhedao 258 were ideal varieties for this experiment due to their high-yielding ability and good stability. Among the experimental pilots, Kaiyuan Demonstration and Multiplication Farm had the strongest discrimination, Huanren Manchu Autonomous County Seed Management Station had the best representativeness, and Fushun Seed Management Station had good discrimination ability and strong representativeness, making it an ideal regional experimental site for this experiment group.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.012 Rice production and circulation play an extremely important role in building and improving the food security system. Taking Jiangsu Province, known as the “first granary” in the Yangtze River Delta region, as an example, this article focused on the factors influencing rice circulation, such as the basic circulation， distribution channels, and brand influence. It particularly analyzed the evolution of the rice production structure and the domestic and foreign circulation pattern in Jiangsu Province, as well as the existing problems and development directions. The article proposed policy suggestions for promoting the orderly development of rice production and the construction of an efficient circulation system in Jiangsu Province, including optimizing the planting structure, variety structure, and product structure; leveraging the role of enterprise associations to strengthen the supervision of the rice market; improving the standard system for high-quality rice products and promoting standardized production; strengthening intellectual property protection and creating a favorable market environment; establishing a “price subsidy separation” system based on market-based pricing.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.013 The key to stable grain production in double cropping rice areas lies in early rice. However, early rice production has long exhibited typical characteristics of “low quality and low efficiency” and “increasing yield without increasing income”, leading to a decrease in planting enthusiasm of farmers for planting, and the phenomenon of “double cropping rice to single cropping rice” or even “rice to cash crop” is prominent. Since the 13th Five Year Plan, Jiangxi has innovated and vigorously demonstrated the implementation of the “planting the same late rice varieties in early and late rice season” model, achieving significant results and promoting the high-quality and efficient development of early rice in double cropping rice areas. However, there were also difficulties and problems in the implementation, such as the lack of suitable varieties, the weak driving force from leading enterprises, the insufficient extension of the industrial chain, the lack of perfect supporting facilities and service support, and the degree of market acceptance to be improved. We therefore proposed the following countermesures and suggestions: accelerate the selection and breeding of suitable varieties for “late rice planted as early rice” and strengthen the demonstration and promotion of technology integration, deepen the construction of the agricultural industry chain and strengthen the driving role of leading enterprises, improve the construction of socialized service system for agricultural machinery, play the synergistic role of “competent government” and “effective market” to improve the market acceptance of the “planting the same late rice varieties in early and late rice season”.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.014 The raw grain supply chain is an important part of the grain supply chain, and there are quality risks and wastage in various aspects of seed selection, planting, collection, drying, storage and sales (circulation). From the perspective of raw grain supply chain, this paper enumerated raw grain quality indicators and quality control links, analyzed the quality risks existing in different links and subjects, and put forward effective control of raw grain quality risks. Firstly, it was necessary to solve the raw grain quality risks from the breeding research and development side. Secondly, it was necessary to establish a quality risk prevention and control mechanism of raw grain supply chain led by the government and participated by the society. Thirdly, to speed up the development of relevant operating standards and technical specifications and deepen industrial applications.

]]> http://www.zgdm.net/EN/10.3969/j.issn.1006-8082.2024.02.015 Ratoon rice, characterized by one sowing and two harvests, saving seed and labor, reducing fertilizer and pesticide, increasing yield and efficiency, is the main production system to increase multiple cropping index and improve the total yield of rice. Zhejiang Province is an important rice production area in the middle and lower reaches of Yangtze River. According to the types of cultivated varieties, the development of ratoon rice in Zhejiang Province was divided into three stages, namely, the initial stage of indica early rice, the transition stage of Yongyou1540, and the rapid development stage of Yongyou series varieties. Taking Quzhou City as an example, the planting area and yield of ratoon rice have been continuously improved in these three stages, and the production efficiency has been significantly improved compared with that of single cropping rice and double cropping rice. This paper further analyzed the development prospect and problems such as lack of technical system of high and stable yield, imbalance among agricultural machinery and agronomy, low support and lack of brand creation during the development of ratoon rice in Zhejiang Province, and put forward the corresponding development strategies, in order to provide reference for the transformation and upgrading of rice production system in Zhejiang Province.

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