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Low light levels during rice (Oryza sativa L.) growing seasons may lead to significant reductions in grain yield and quality. The effect of shading stress on remobilization of nonstructural carbohydrates (NSC) from the stem plus sheath (SPS) to the grain, a process crucial to rice grain formation, was investigated. Field shading experiments were conducted in Hanyuan and Wenjiang, China, using two rice varieties (Huanghuazhan and Guichao II) subjected to shading stress after heading. Stored NSC of 60.00-159.15 g m-2 were remobilized from SPS after heading, contributing 9.63%-23.63% to grain dry weight at maturity. Shading stress resulted in the 23.99%-50.30% and 31.65%-61.33% reduction in NSC content of SPS at 20 d after heading (DAH20) and maturity stages, respectively. This contributed to the 13.80%-89.00% increase in the remobilization of stored NSC from SPS to the grain (RASN) and 15.86%-73.30% increase in remobilization percentage of removed NSC from SPS to the grain (RPRN). The effect of shading stress on remobilization differed between sites and varieties. Owing to a greater sink capacity, shading stress led to a higher RASN and RPRN from heading to DAH20 for ‘Huanghuazhan’ in Hanyuan. To compensate for photosynthate deficiency under shading stress, rice is adapted to remobilize stored NSC during early grain filling stages. Consequently, grain yield loss caused by shading could be reduced by increasing the SPS remobilization ability (especially in low light areas). Increasing NSC accumulation in SPS before heading for later remobilization may be a feasible way to alleviate rice yield loss under adverse light conditions.

The yield and nitrogen use efficiency (NUE) of hybrid rice combinations are closely related to restorer line. Therefore, it is essential to evaluate the agronomic characteristics of restorer lines with high yield and high NUE (HYHN). However, it is unclear which restorer lines are HYHN, and neither have the common agronomic traits of the HYHN restorer lines been identified. Aiming to address this issue, we conducted two filed experiments using three nitrogen applications, which screened five HYHN restorer lines from 15 indica restorer lines. Yield, NUE and nutrient transportation of restorer lines with different yields and NUE types were examined. Yield and total nitrogen absorption in aboveground biomass (TNA) increased, whereas NUE for grain production decreased with increasing nitrogen application levels. The HYHN restorer lines had large spikelets and high weight per panicle that were significantly positively correlated with yield and NUE. Therefore, large sink potential may be beneficial for both yield and NUE. We further studied the differences in nutrient transportation to panicles between the HYHN and low yield and low NUE (LYLN) restorer lines and found that the former had a higher nitrogen absorption level and dry matter weight ratios of panicle in maturity. Moreover, the HYHN lines also had a higher root and neck-panicle node bleeding intensity per stem after heading and more developed vascular bundles of neck-panicle nodes and leaves than the LYLN lines, which could contribute to the transportation of nutrients from root to ground and from stem and leaf to spike. Therefore, the advantages of large sink potential of the HYHN restorer lines include large nutrient accumulation in and distribution to the panicles and smooth flow of nutrients along the transportation channels.

Few studies have tested the influence of climatic factors on yields by adjusting sowing dates at both low and high altitudes. We investigated the influence of the synergistic effects of temperature...

Many indexes have been demonstrated to evaluate the lodging resistance of rice, but most of them are complex or not representative. Thus, we propose a simple and low-cost index, called relative culm wall thickness (RCWT), which can be calculated as the ratio of the basal internode wall thickness to its diameter, to measure the lodging characteristics of rice. A field experiment with 20 indica hybrid rice varieties was conducted in Dayi, Sichuan, China, in 2017 and 2018. The results show that RCWT was significantly negatively correlated with the lodging index, visual lodging rate, plant inclination angle, and bending moment, while it was significantly positively correlated with culm wall thickness, breaking resistance, cellulose, and lignin. Compared with the middle and low RCWT types, the high RCWT type had a lower plant height and center of gravity. Meanwhile, the short basal internodes, thick culm wall thickness, and small pith diameter increased the fullness of the stem, which increased the content of cellulose and lignin in the stem, and thus enhanced the bending resistance and decreased lodging index of the stem. These results indicate that the RCWT can be used as an important index to evaluate the lodging resistance of rice.

Controlled-release fertilizers (CRFs) are known to improve grain yield and N-use efficiency (NUE) without intensive labor input in crop production. Here, we report field experiments conducted to in...

In rice (Oryza sativa L.), yield is related to characteristics of branches and spikelets. To investigate the effects of late sowing date on differentiation and degeneration of spikelets in rice, field experiments were conducted in Chongzhou and Hanyuan, China. Differentiation and survival of branches and spikelets in Hanyuan were lower than that of Chongzhou, whereas degeneration was greater than that of Chongzhou. In Chongzhou, sowing date affected differentiation and survival of primary, secondary, and total branches, as well as differentiation and degeneration of secondary and total spikelets. In Hanyuan, sowing date affected degeneration of secondary and total branches, and the survival and degeneration of primary spikelets. Late-sown plants experienced higher temperatures in the jointing to heading period, and there were higher sunshine hours. Rainfall and humidity were higher in Chongzhou, but lower in Hanyuan. Late sowing increased differentiation, degeneration, and survival number of branches and spikelets in Chongzhou. However, in Hanyuan, late sowing increased differentiation and degeneration of branches, but decreased survival of branches, which reduced spikelet differentiation and degeneration, resulting in fewer branches. Thus, the key to higher yield in Chongzhou was to increase differentiation of spikelets, whereas in Hanyuan, it was to reduce degeneration of branches and spikelets.

Chalkiness, one of the key factors in determining the market price and quality of rice grains, is markedly influenced by the environment. This study aimed to investigate the effectiveness of shading on rice chalkiness by conducting a field experiment in Wenjiang, Sichuan, China, in 2013 and 2015. Rice cultivars IIyou 498 and Yixiangyou 2115 were selected and shaded during the grain filling period; this resulted in a 53% shading environment. The results showed that chalkiness, caryopsis and amyloplast development, amylose content, and amylopectin chain-length distribution of rice grains, were markedly affected by shading. Shading significantly increased chalky rice rate and chalkiness degree of rice grains at the bottom of the panicle, which contributed to the increase in chalkiness of the entire panicle. Shading had a greater influence on grains at the bottom spikelet positions than on those at the top and middle positions. More loosely packed amyloplasts with greater airspace and reduction in amylose content of grains at the bottom spikelet positions were possibly due to the significant delay in the development of caryopsis. Furthermore, except for the bottom spikelet positions of Yixiangyou 2115, a reduction in short-length chains coupled to an increase in long-length chains of amylopectin was noted under shading. Shading increased rice chalkiness primarily by postponing caryopsis development at the bottom spikelet positions and disturbing the starch characteristics of rice grains. Therefore, more attention needs to be focused on the grains positioned at the bottom of panicle.

China is the main global garlic and rice producer and garlic–rice (GR) therefore represents an important crop planting system. However, the relationship between the agricultural output and greenhouse gas emissions under the GR system remains unknown. In this study, we analyzed the greenhouse gas emissions, crop yield, net economic benefits, and other potential influencing factors of the GR system, to explore the impact of different crop systems on food output and the environment. We used a wheat–rice (WR) system as the control and collected data for two years (2017–2018). Net economic benefits of the GR system were 28670.2 and 35799.8 CNY ha–1 in the two years, respectively, much higher than corresponding values of 2718.4 and 1825.6 CNY ha–1 for the WR system. Global warming potential was 78.43% and 168.66% higher for the GR system in the same years. Compared to the WR system, the global warming potential of the GR system was concentrated in the dry season, with the main contributor being N2O emissions (57.62%). Two-year greenhouse gas emission intensities calculated using net economic benefits (0.11 and 0.08) were less than one-fifth of those of the WR system. The GR system could therefore be an effective option for generating high net economic benefits with a low greenhouse gas emission intensity.

Yield, taste quality, and cultivar utilisation improvements are important research topics in indica rice breeding. Herein, we compared the relative effectiveness and relationship of three taste evaluation methods, namely, chemical composition, Rapid Visco Analyser (RVA), and taste analyser. We assessed associations among these methods using 36 indica varieties commonly grown in Yunnan, Sichuan, and Guizhou, China. Temperature and sunlight duration during grain filling influenced rice cooking quality. Varieties with high taste quality had low amylose and protein contents; high peak viscosities and breakdowns; and low hold viscosities, setbacks, and final viscosities. Protein and combined protein and amylose explained 38.6% and 62.1% of the variation in taste value, respectively. The RVA profile was affected by protein, amylose, and amylopectin contents and explained 60.5% of the taste-value variation. This study lays the foundation for taste evaluation of high-quality rice varieties early in the breeding process, which can improve cultivation and marketing potential.

We aimed to clarify the effectiveness of polyaspartic acid (PASP)-urea on nitrogen (N) accumulation and N use efficiency in rice. We compared PASP-urea with conventional urea with two N management ...

Shading stress has become a worldwide phenomenon and can lead to rice (Oryza sativa L.) yield loss by decreasing the seed setting percentage (the percentage of filled spikelets to total spikelets per panicle), which depends primarily on spikelet fertility. However, the effect of shading stress on rice spikelet pollination and fertilization processes is not fully understood. Here, a field experiment, spanning two years (2019 and 2020), was conducted using two rice varieties (Huanghuazhan and Fyou 498) grown under full sunlight and 53 % shade. No significant difference in pollen I2-KI staining rate was observed between the full sunlight control and the shading treatment in 2019 and 2020. However, shading stress significantly decreased the in vitro pollen germination rate of spikelets that opened 5 d and 8 d after shading in 2020. Shading stress also significantly reduced the anther dehiscence rate of both varieties in both years (except for Huanghuazhan at 2 d after shading in 2019), and a mass of pollen grains remained in the anthers. Together with a reduction in the stigma exsertion rate, shading stress reduced the number of pollen grains per stigma by 29.4–71.2 % and the number of germinated pollen grains per stigma by 9.8–63.2 %. Consequently, shading stress significantly decreased the fertilization rate in these varieties, which contributed to a marked yield loss. We assert that shading stress decreased the fertilization rate by inhibiting key pollination and fertilization processes, particularly anther dehiscence and pollen grain release.

Ratoon rice (RR) is characterized by higher production combined with enhanced rice quality. However, limited information is available regarding the mechanism of quality enhancement of RR. In this study, three varieties were used to investigate differences in the components, the fine structural and physicochemical properties of starch, and the textural characteristics of cooked rice between the main crop and RR. Compared to the main crop, RR significantly increased the starch and amylose content, amylose to amylopectin ratio, weight average molecular weight of the starch granule, and fa (DP 6–12) and fb1 (DP 13–24) chain proportions of amylopectin. However, it decreased the amylopectin and protein content, mean diameter and number average molecular weight of the starch granule, and fb2 (DP25-36) and fb3 (DP > 37) chain proportions of amylopectin. This contributed to an increase in branching degree, polydispersity, ΔHgel, Tc-R, ΔHret, and retrogradation percentage, as well as a decrease in the average chain length and polymerization degree of amylopectin and crystallinity degree, and water solubility of RR. These differences might contribute to the increase in hardness and decrease in stickiness of cooked RR.

Polyaspartic acid (PASP)-urea is known to increase crop yield. Field experiments were conducted to compare the morphological and physiological characteristics of the leaves between plots treated with urea (conventional urea or PASP-urea) and subject to different nitrogen (N) management methods [farmers’ standard fertilization practice (FFP, two splits) or optimized N management (ONM, four splits)] in Sichuan, China, in 2014 and 2015. A no-added-N plot served as the control. Grain yield was significantly associated with increased number of green leaves, total leaf area, chlorophyll concentration of rice leaves after the heading stage, photosynthetic rate per leaf lamina and accumulated temperature of senescence rate acceleration and deceleration. PASP-urea significantly enhanced the photosynthetic capacity of leaves to improve dry matter accumulation rate of the panicle after the heading stage over conventional urea, mainly by increasing the number of green lamina, leaf lamina area, chlorophyll con...

Light is a basic environmental factor required for plant growth and development; however, these are not only affected by light quantity, but also by light quality - light and radiation of different wavelengths and different compositions. In four different rice varieties (Oryza sativa L.), two kinds of shading materials, white cotton yarn (Shading (W)) and black nylon net (Shading (B)) were used to simulate cloudy days. Yield decreased under Shading (W) (15.3–17.7%) and Shading (B) (16.6–20.0%) compared to under sunny day (CK), and different effects on rice quality, which is mainly affected by changes in light quality, were observed. The change in light quality (Blue, Green, Red and R/FR proportions) represented under Shading (W) was significantly different from that under CK and Shading (B) conditions. Red light composition under Shading (W) was closer to that of the cloudy day condition. The proportion of blue light under Shading (W) was significantly lower than that under CK conditions; under Shading (B), it was higher than that under all conditions. The differences in light quality may affect photosynthesis in leaves and final starch synthesis, resulting in increased chalky grain rate, chalkiness, and poor rice quality. White cotton yarn as the shading material for further research used to simulate the influence of the light environment on rice growth under cloudy conditions will be better than black net.

Increase in grain nitrogen concentration (GNC), which is directly affected by nitrogen (N) application, can help overcome the issues of malnutrition. Here, the effects of urea type (polyaspartic acid (PASP) urea and conventional urea) and N management method (two splits and four splits) on GNC and N concentration of head rice were investigated in field experiments conducted in Sichuan, China, in 2014 and 2015. N concentration of grain and head rice were significantly (P

Chalkiness is a major concern in rice production and its acceptance and is increased by shade stress. However, the relationship between rice chalkiness and the structural and thermal properties of starch is unclear. Here, we investigated the effect of shade stress on rice starch properties. The chalky grain rate and chalkiness degree significantly decreased with the amylose content, Mn, and ΔH and increased with surface area- and volume-weighted mean diameters, branching degree, ratio of 1022/995 cm-1, and molecular weight polydispersity. Shade stress significantly increased the volume- and surface area-weighted mean diameters and Mw and decreased the amylose content, A chain proportion of amylopectin, Mn, and regularity of starch. These effects led to an increase in the molecular weight polydispersity and branching degree and a decrease in the crystallinity degree and 1045/1022 cm-1 ratio, thereby reducing starch ΔH and uniformity. These factors contributed to increased chalkiness of rice under shade stress.

Unreasonable application of nitrogen fertilizer to cropland decreases nitrogen use efficiency of crop. A large amount of nitrogen loss to environment through runoff, leaching, ammonia volati-lization, nitrification-denitrification, etc., causes water and atmospheric pollution, poses serious environmental problems and threatens human health. The type of nitrogen fertilizer and its application rate, time, and method have significant effects on nitrogen loss. The primary reason for nitrogen loss is attributed to the supersaturated soil nitrogen concentration. Making full use of environmental nitrogen sources, reducing the application rate of chemical nitrogen fertilizers, applying deep placement fertilizing method, and applying organic fertilizers with chemical nitrogen fertilizers, are effective practices for reducing nitrogen loss and improving nitrogen use efficiency. It is suggested that deve-loping new high efficiency nitrogen fertilizers, enhancing nitrogen management, and strengthening the monitoring and use of environmental nitrogen sources are the powerful tools to decrease nitrogen application rate and increase efficiency of cropland.氮肥的不合理施用导致氮肥利用率低下,大量氮素通过径流、淋溶、氨挥发、硝化-反硝化作用等途径损失到环境中,从而对水体、大气造成污染,带来严重的环境问题,影响人类健康.施氮量、施肥时间和方式,以及肥料种类对氮素流失量的影响显著.土壤氮素浓度过饱和是导致氮素大量流失的最根本原因,充分利用环境供氮量,减少化学氮肥施用量,采用深施等技术,以及配合施用有机肥,可以有效降低氮素的损失,提高氮素利用率.在开发应用新型高效氮肥和强化氮肥高效管理技术研究的同时,加强环境氮素的监测和利用力度,是实现减氮增效的有力手段.

Low radiation caused by industrial development and environment change has become a limitation in crop production in China. Field experiments were conducted to investigate the effect of shading stress on photosynthetic and chlorophyll fluorescence characters, as well as grain yield and yield components of rice from 2010 to 2012, in Sichuan, China. Rice cv. IIyou 498, Gangyou 188, Dexiang 4103, Gangyou 527, and Chuanxiang 9838 were selected and shaded during grain filling period, which resulted in 53% shading environment (achieved with white cloth above the rice canopy). Shading increased the flag leaf chlorophyll (Chl) content and maximum efficiency of PSII photochemistry under dark-adaption (Fv/Fm), but decreased the net photosynthetic rate, electron transport rate (ETR), saturation irradiance (PARsat), and maximum electron transport (Jmax), which resulted in a sharply falling grain yield mainly due to reduced spikelet filling and grain weight. The shading tolerances were different in different rice varieties. Maximum net photosynthetic rate (Pmax), light saturation point (LSP), quantum yield of PSII (ΦPSII), and photochemical quenching (qP) of Gangyou 188 were reduced under shading. However, IIyou 498 had its adaptive capacity to shading enhanced by increasing the Chl content to improve light-harvesting potential as well as increased Pmax, LSP, Fv/Fm, and ΦPSII. In addition, there was reduced non-photochemical quenching (NPQ), while maintaining a more stable ETR, PARsat, and Jmax to enhance light-use efficiency and reduce the dissipation of light energy, which relieved damage to spikelet filling and resulted in a smaller reduction in grain yield of IIyou 498. Therefore, the improvement in light-harvesting and -use capability and increased spikelet filling under shading stress might be important characteristics for plant breeders. For example, IIyou 498 can be selected as a shade-tolerant variety.

Reasonable management of nitrogen (N) and the development of N fertilizers with higher use efficiency are the two main methods to increase rice yield. The effects of optimized nitrogen management (ONM) and polyaspartic acid urea treatment (PAU) on rice dry matter production and grain yield under different soil conditions in Sichuan, China, were studied in 2013. When the different N management regimes were applied there were differences in the rice tiller number, dry matter production, and yield observed. At Shehong, ONM3 (a 15% increase in the N rate over the farmer’s fertilizer practice) had the highest grain yield, and significantly ( P P P

In this study, we aimed to investigate the effects of nitrogen (N) management and polyaspartic acid urea (PASP-urea) on N utilization and soil N balance of midseason rice in southwest China. Field experiments with no N treatment, famer's fertilizer practice (FFP), three optimized nitrogen managements (ONMs), and three PASP-urea treatments (PASPTs) were conducted at Shehong and Wenjiang, Sichuan Province, in 2013. The results showed that the N fertilizer increased crop N uptake and total N output, but intensified the apparent N losses. Compared to FFP, ONMs and PASPTs (excluding ONM2 and PASPT1 at Shehong) increased N accumulation in plant organs before anthesis, which significantly (p

On planet earth, the only place so far known that is suited to human life, human beings are the life form with the greatest vitality and ability. Our attitudes and concepts in relation to the world should not stop at understanding and changing it; rather, they should be sublated into a new worldview through which we can scientifically understand and rationally improve the world. Only on the basis of this new worldview can we find a new focus and a new set of values, a new way of living and acting. “Beautiful China,” as a literary metaphor for the goal of constructing ecological civilization, vividly and fully expresses a completely new vision for socialist modernization with Chinese characteristics. The building of ecological civilization is a social scheme that needs to be based on clear, comprehensive, long-term and scientific ecological values, guided by ideas and regulated by institutions. It calls for the conscious action of all members of society.

Effects of shading at the flowering and grain filling stages on osmotic regulation substance content and protective enzyme activities in the leaves of different rice genotypes (e.g., IIyou 498, Gangyou 188, Dexiang 4103, Gangyou 527 and Chuanxiang 9838) were investigated. The results showed that the malondialdehyde content of Gangyou 188 significantly increased under shading, whereas those of IIyou 498, Dexiang 4103, Gangyou 527 and Chuanxiang 9838 showed no significant differences compared to the control. The soluble sugar content significantly decreased in IIyou 498, Gangyou 188, Dexiang 4103 and Chuanxiang 9838, whereas it did not significantly increase in Gangyou 527 under the weak light conditions (shading). Moreover, the soluble protein content in the leaves of different genotypes tended to decrease under shading. Further, the protective enzyme activities in the leaves varied in different rice genotypes under the shading treatment. Based on the osmotic regulation substance content and the protective enzyme activities in the leaves of different rice genotypes, it was concluded that Gangyou 188 and Gangyou 527 had strong abilities to adapt to the low light conditions. In addition, the mechanism of damage to rice leaves in different genotypes under shading was discussed.

基于当代中国社会的道德文化语境, 本文重新反省了近代百余年来中国现代化进 程中道德文化传统的蝉脱与嬗变, 以及隐含在这一脱变过程中的中国现代性与中国道 德文化传统之间的复杂关系, 推导并论证了这样一个基本学术判断: 即近世中国企图 脱出传统道德文化的自由与保守之两分, 表明了“传统之后”的中国道德文化陷入了 摆脱传统与持守传统的两难纠结, 而最终的结果看似已然超乎“传统之外”, 实则仍 然在“传统之中”, 只不过社会主义新道德以革命性变革的方式, 在近代百年的“诸 神论战”中脱颖而出, 成为现代中国的主流道德文化。然而. 她并非超脱于“传统之 外”的纯粹异物, 而是且只能是中国道德文化传统和中国现代性的新的延展, 仍然是 漫长、深厚、连贯的中国道德文化传统的“变体链”。 关键词: 道德文化 现代性 传统之后 传统之中 传统之外 This paper reexamines the metamorphosis of China’s moral and cultural traditions in the course of modernization over the last hundred years and the complex relationship between Chinese modernity and the moral and cultural traditions latent in this metamorphosis, in the context of contemporary China. We deduce and demonstrate the following basic conclusion: modern China’s attempt at resolving the dichotomy of liberalism and conservatism of moral cultural traditions shows that the country’s post-tradition ethical culture faces the dilemma of whether to hold on to tradition or abandon it. However, the final result may be that modern Chin...

Ethics in the modern context is under the dual pressure of scientific-technological rationality and market commercialization, which has led to breakthroughs in the original boundaries of knowledge and academic methodology. The gradual separation of the domain of public life and that of private life in modern society and the former’s increasing pressure on the latter, in addition to the above dual pressure on ethics, is causing a dramatic transformation of the structure of ethical knowledge itself. All of these raise new theoretical problems for ethics and ethicists in the modern context. Answering and solving these problems makes sense for the future development of ethics as one of the classic humanities, and tests modern ethicists’ ability to realize their moral and theoretical duties.

The present state of the study of philosophy in China cannot be understood if the introduction of Western philosophy, including Marxism, in the early decades of the 20th century is ignored. During the first half of the past century, philosophy flourished at Peking University with a heavy emphasis on social and political theory, as well as at Tsinghua University, which focused more on professionalization of the discipline, logic, epistemology and the history of philosophy. From 1957 to 1979, philosophical studies suffered severely under an increasingly unfavourable political climate. It is only recently that departments of philosophy have been reconstructed, not only in Beijing but also in all major universities. Like their colleagues in other disciplines, many philosophers are nowadays struggling with the dichotomy between the old and the new, the Chinese and the Western tradition, and resisting an uncritical absorption of Western ideas. Finally, some observations are made on the lectures that Jürgen Habermas gave in China in 2001.

A field experiment was conducted to study the effects of four cultivation modes (conventional tillage, no-tillage, conventional tillage + stubble-remaining, and no-tillage + stubble-remaining) on the activities of urease, acid phosphatase, protease, and cellulose in different soil layers in a broadcasting rice seedlings paddy field. Under the four cultivation modes, the activities of test enzymes were higher in upper than in deeper soil layers, and had a greater difference between the soil layers under no-tillage + stubble-remaining. In upper soil layers, the activities of test enzymes were higher in the treatments of no-tillage than in the treatments of conventional tillage, being the highest under no-tillage + stubble-remaining and the lowest under conventional tillage. In deeper soil layers, the test enzyme activities were the highest under conventional tillage + stubble-remaining, followed by no-tillage + stubble-remaining, no-tillage, and conventional tillage. During the growth period of rice, soil urease and cellulose activities were lower at tillering stage, increased to the maximum at booting stage, and decreased then, soil acid phosphatase activity was higher at tillering stage but lower at elongating stage, whereas soil protease activity peaked at tillering and heading stages.

Effects on Soil Fertility and Microbial Populations of Broadcast-Transplanting Rice Seedlings in High Standing-Stubble Under No-Tillage in Paddy Fields

A field experiment was conducted on a paddy field to study the effects of returning straw to soil and different tillage methods (no-tillage + returning straw, no-tillage, tillage + returning straw, and tillage) on the fertility level and microbial quantities of different soil layers. The results showed that in upper soil layer, the organic matter content in treatment 'no-tillage + returning straw' was 5.33, 2.79, and 5.37 g x kg(-1) higher than that in treatments 'no-tillage', 'tillage + returning straw', and 'tillage', respectively, and the contents of total and available N, P and K in treatment 'no-tillage + returning straw' were also the highest, followed by in treatments 'no-tillage' and 'tillage + returning straw', and in treatment 'tillage'. In deeper soil layer, all the fertility indices were higher in treatment 'tillage + returning straw'. Treatments of 'returning straw to soil' had the highest quantities of soil microbes. The quantities of bacteria, fungi, and actinomycetes in upper soil layer were the highest in treatment 'no-tillage + returning straw', and thus, the cellulose decomposition intensity in this treatment at maturity period was 26.44%, 79.01%, and 98. 15% higher than that in treatments 'tillage + returning straw', 'no-tillage', and 'tillage', respectively. In deeper soil layer, the quantities of bacteria, fungi, and actinomycetes were the highest in treatment 'tillage + returning straw'. Treatment 'no-tillage + returning straw' had the features of high fertility and abundant microbes in surface soil layer. The quantities of soil bacteria and actinomycetes and the decomposition intensity of soil cellulose were significantly positively correlated with soil fertility level.

The study with stronger tillering hybrid rice ' D-you 527' showed that the more the irregularity of the seedlings horizontal distribution, the more colony stem-tillers the plants would have. Such a difference was significant 34 days after transplanting, but not significant at full heading stage. After transplanting, the trend that the variation coefficient increased with increasing irregularity of horizontal distribution presented gradually, and the difference became significant after jointing stage. Comparing with uniform distribution, an irregular horizontal distribution of the seedlings could benefit the canopy light transmittance rate and the panicle characteristics of rice.