The use of RNA interference (RNAi) technology to control pests is explored by researchers globally.  Even though RNA is a new class of pest control compound unlike conventional chemical pesticides, the evolution of pest resistance needs to be considered.  Here, we first investigate RNAi-based biopesticide resistance of Fusarium asiaticum, which is responsible for devastating diseases of plants, for example, Fusarium head blight.  Five resistant strains were isolated from 500 strains that treated with UV-mutagenesis.  The mutation common to all of the five resistant mutants occurred in the gene encoding Dicer2 (point mutations at codon 1005 and 1007), which were under strong purifying selection pressure.  To confirm whether the mutations in Dicer2 confer resistance to RNAi, we exchanged the Dicer2 locus between the sensitive strain and the resistant strain by homologous double exchange.  The transformed mutants, Dicer2^R1005D and Dicer2^E1007H, exhibited resistance to dsRNA in vitro.  Further study showed that mutations of R1005D and E1007H affected the intramolecular interactions of Dicer2, resulting in the dysfunction of RNase III domain of Dicer2.  The amount of sRNAs produced by Dicer2^R1005D and Dicer2^E1007H was extremely reduced along with variation of sRNA length.  Together, these findings revealed a new potential mechanism of RNAi resistance and provided insight into RNAi-related biopesticide deployment for fungal control.

The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.  This problem may be solved by increasing the seeding rate during seedling production while reducing the number of seedling trays.  This study conducted field experiments from 2021 to 2022, using transplanting seedling ages of 10 and 15 days to explore the effects of 250, 300, and 350 g/tray on the seedling quality, mechanical transplantation quality, yields, and economic benefits of rice.  The commonly used combination of 150 g/tray with a 20-day seedling age in rice production was used as CK.  The cultivation of seedlings under a high seeding rate and short seedling age significantly affected seedling characteristics, but there was no significant difference in seedling vitality compared to CK.  The minimum number of rice trays used in the experiment was observed in the treatment of 350–10 (300 g/tray and 10-day seedling age), only 152–155 trays ha–1, resulting in a 62% reduction in the number of trays needed.  By increasing the seeding rate of rice, missed holes during mechanical transplantation decreased by 2.8 to 4%.  The treatment of 300–15 (300 g/tray and 15-day seedling age) achieved the highest yields and economic gains.  These results indicated that using crop straw boards can reduce the application of seedling trays.  On that basis, rice yields can be increased by raising the seeding rate and shortening the seedling age of rice without compromising seedling quality.

Soybean seed isoflavones are a type of secondary metabolites that can provide health and nutrition benefits for humans.  In our previous study, a stable quantitative trait locus (QTL) qIF05-1 controlling the seed isoflavone content in soybean was detected on chromosome (Chr.) 05 in a recombinant inbred line (RIL) population from a cross of Huachun 2×Wayao.  In this study, the parental lines were re-sequenced using the Illumina Solexa System with deep coverage.  A total of 63,099 polymorphic long insertions and deletions (InDels) (≥15 bp) were identified between the parents Huachun 2 and Wayao.  The InDels were unevenly distributed on 20 chromosomes of soybean, varying from 1,826 in Chr. 12 to 4,544 in Chr. 18.  A total of 10,002 long InDels (15.85% of total) were located in genic regions, including 1,139 large-effect long InDels which resulted in truncated or elongated protein sequences.  In the qIF05-1 region, 68 long InDels were detected between the two parents.  Using a progeny recombination experiment and genotype analysis, the qIF05-1 locus was mapped into a 102.2 kb genomic region, and this region contained 12 genes.  By RNA-seq data analysis, genome sequence comparison and functional validation through ectopic expression in Arabidopsis thaliana, Glyma.05G208300 (described as GmEGL3), which is a basic helix-loop-helix (bHLH) transcription factor in plants, emerged as the most likely confirmed gene in qIF05-1.  These long InDels can be used as a type of complementary genetic method for QTL fine mapping, and they can facilitate genetic studies and molecular-assisted selection breeding in soybean.

Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.  However, the effects of straw mulching on dissolved organic matter (DOM) runoff loss from black soil are not well studied.  How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.  Here, a straw mulching treatment was compared to a no mulching treatment (as a control) on sloping farmland with black soil erosion in Northeast China.  We divided the soil into large macroaggregates (>2 mm), small macroaggregates (0.25–2 mm), and microaggregates (<0.25 mm).  After five rain events, the effects of straw mulching on the concentration (characterized by dissolved organic carbon (DOC)) and composition (analyzed by fluorescence spectroscopy) of runoff and soil aggregate DOM were studied.  The results showed that straw mulching reduced the runoff amount by 54.7%.  Therefore, although straw mulching increased the average DOC concentration in runoff, it reduced the total runoff DOM loss by 48.3%.  The composition of runoff DOM is similar to that of soil, as both contain humic-like acid and protein-like components.  With straw mulching treatment, the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.  Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.  A variation partitioning analysis (VPA) indicated that the DOM concentration and composition of microaggregates explained 68.2% of the change in runoff DOM from no mulching plots, while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.  Taken together, our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates, thus effecting DOM compositions in soil and reducing the DOM loss in runoff.  These results provide a theoretical basis for reducing carbon loss in sloping farmland.

Recently developed ‘super’ rice cultivars with greater yield potentials often suffer from the problem of poor grain filling, especially in inferior spikelets.  Here, we studied the activities of enzymes related to starch metabolism in rice stems and grains, and the microstructures related to carbohydrate accumulation and transportation to investigate the effects of different water regimes on grain filling.  Two ‘super’ rice cultivars were grown under two irrigation regimes of well-watered (WW) and alternate wetting and moderate soil drying (AWMD).  Compared with the WW treatment, the activities of ADP glucose pyrophosphorylase (AGPase), starch synthase (StSase) and starch branching enzyme (SBE), and the accumulation of non-structural carbohydrates (NSCs) in the stems before heading were significantly improved, and more starch granules were stored in the stems in the AWMD treatment.  After heading, the activities of α-amylase, β-amylase, sucrose phosphate synthase (SPS) and sucrose synthase in the synthetic direction (SSs) were increased in the stems to promote the remobilization of NSCs for grain filling under AWMD.  During grain filling, the enzymatic activities of sucrose synthase in the cleavage direction (SSc), AGPase, StSase and SBE in the inferior spikelets were increased, which promoted grain filling, especially for the inferior spikelets under AWMD.  However, there were no significant differences in vascular microstructures.  The grain yield and grain weight could be improved by 13.1 and 7.5%, respectively, by optimizing of the irrigation regime.  We concluded that the low activities of key enzymes in carbon metabolism is the key limitation for the poor grain filling, as opposed to the vascular microstructures, and AWMD can increase the amount of NSC accumulation in the stems before heading, improve the utilization rate of NSCs after heading, and increase the grain filling, especially in the inferior spikelets, by altering the activities of key enzymes in carbon metabolism.

Oomycete, particularly Phytophthora species, causes the most devastating crop diseases, such as potato late blight, and threatens the sustainable crop production worldwide.  Our previous studies identified Resistance to Phytophthora parasitica 1 (RTP1) as a negative regulator of Arabidopsis resistance to multiple biotrophic pathogens and RTP1 loss-of-function plants displayed rapid cell death and reactive oxygen species (ROS) production during early colonization of P. parasitica.  In this study, we aim to decipher the mechanism of RTP1-mediated cell death, and identify a member of vaculoar processing enzymes (VPEs), γVPE, playing a role in rtp1-mediated resistance to P. parasitica and cell death occurrence.  Our results showed up-regulation of the expression of γVPE as well as increased VPE/caspase 1-like protease activity in P. parasitica-infected rtp1 mutant plants.  Besides, we found that the VPE/caspase 1-like protease activity was required for the cell death occurrence in Arabidopsis plants during the infection of P. parasitica as well as rtp1-mediated resistance to P. parasitica.  Further pathogenicity assays on either Arabidopsis γvpe mutant plants or leaves of Nicotiana benthamiana with transient overexpression of γVPE demonstrated γVPE could positively affect plant resistance to P. parasitica.  Together, our studies suggest that γVPE might function as an important regulator of plant defense and cell death occurrence in response to P. parasitica infection, and VPE/caspase 1-like protease activity is required for rtp1-mediated resistance to P. parasitica.

Diglyphus wani (Hymenoptera: Eulophidae) is a dominant parasitoid that attacks agromyzid leafminers.  Two reproductive types occur in D. wani: arrhenotoky (in which virgin females produce only male offspring; and virgin females mate with males to produce bisexual offspring) and thelytoky (in which virgin females produce female offspring).  As a potential biological control agent, exploring the differences in the relevant biological parameters of both strains is necessary.  In this study, comparisons between the two strains of D. wani were performed by evaluating the life table and host-killing rate.  The thelytokous strain exhibited significantly better life table parameters than its arrhenotokous counterpart.  Higher values for the intrinsic rate of increase, finite rate of increase, net reproductive rate, and fecundity were found in the thelytokous strain.  The thelytokous strain also performed better than the arrhenotokous strain in terms of net parasitism, host-feeding, host-stinging, and total host-killing rates.  Thus, populations of the thelytokous strain could grow fast and kill more hosts.  In conclusion, the thelytokous strain of D. wani may be the more promising biological agent against agromyzid leafminers compared to its arrhenotokous counterpart.  Also, since the thelytokous strain of D. wani is only known to produce females, it should be given priority in future biocontrol applications owing to the cost savings of breeding only females.

Super-absorbent polymers (SAPs) are widely used chemical water-saving materials, which play an active role in the accumulation of soil water and the improvement of soil structure.  Little is known about their performance with repeated usage or about factors influencing their efficiency under alternate wetting and drying cycles.  In this study, various concentrations of SAP (0, 0.1, 0.2 and 0.3%) in soil following three continuous wetting and drying cycles (T1, T2 and T3), were studied to determine effects on soil structure stability and hydro-physical properties.  The results indicated that the SAP improved soil water supply capacity under conditions of mild drought (T2) and sufficient irrigation (T3) at concentrations of 0.2 and 0.3%, but a reduction was observed under severe drought conditions (T1), which was negatively correlated with the SAP concentration.  The physical adsorption of the SAP by soil and the chemical connection between the SAP and soil mineral colloids as Si-O-Si bonds, -OH bonds and different crystalline silica were the important factors that directly lead to the reduction of water retention capacities of the SAP with alternating wet and dry conditions.  Compared with the control, the soil liquid phase ratios of the SAP treatments were increased by 8.8–202.7% in the T1 and T2 cycles, which would have led to a decrease in the soil air phase ratios.  After repeated wetting and drying cycles, the SAP treatments increased the amount of >0.25 mm soil aggregates and the contents of water-stable macro-aggregate (R_0.25), and decreased the amount of <0.053 mm soil aggregates, especially with higher concentrations of the SAP.  Increases in mean weight diameter (MWD) and geometric mean diameter (GMD), and declines in fractal dimension (D) and unstable aggregates index (E_LT) were all observed with the SAP treatments, which indicated an improvement in soil stability and structure.  It was concluded that the distribution and stability of soil aggregates and soil water supply capacity was closely related to SAP concentration, soil moisture condition and the interaction between the SAP and soil particles

Genetic linkage maps are important for quantitative trait locus (QTL) and marker-assisted selection breeding.  The wolfberry (Lycium spp.) is an important food and traditional medicine in China.  However, few construction genetic linkage maps have been reported because of the lack of genomic and genetic resources.  In this study, a population of 89 F₁ seedings was derived from a cross between two heterozygous parents, L. chinense var. potaninii ‘BF-01’ (female) and L. barbarum var. auranticarpum ‘NH-01’ (male), in order to construct a genetic linkage map using simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers based on the double pseudo-test cross mapping strategy.  The resulting genetic map consisted of 165 markers (74 AFLPs and 91 SSRs) distributed across 12 linkage groups and spanned a total length of 557.6 cM with an average distance of 3.38 cM between adjacent markers.  The 12 linkage groups contained 3 to 21 markers and ranged in length from 8.6 to 58.3 cM.  Twenty-nine segregated markers distributed in the map were mainly located on LG4 and LG9 linkage groups at P<0.05.  This is the first linkage map of Lycium species using SSR and AFLP markers, which can serve as basis for improving genes and selective breeding of the genome assembly.

We studied gas-exchange, chlorophyll pigments, lipid peroxidation, antioxidant enzymes, and biomass partitioning responses in seedlings of four wolfberry species (Lycium chinense Mill. var. potaninii (Pojark.) A. M. Lu, Lycium chinense Mill., Lycium barbarum L., and Lycium yunnanense Kuang & A. M. Lu) under four water supply regimes.  In all four species, drought affected seedlings in terms of chlorophyll content, net photosynthesis rate (P_n), transpiration rate (E), and lipid peroxidation.  Drought also increased some antioxidant enzyme activities, such as peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX).  Significant changes in dry biomass partitioning also occurred in response to water stress.  In particular, dry biomass of leaves and fruits decreased significantly.  L. chinense Mill. and L. barbarum L. possessed greater drought tolerance and exhibited superior antioxidant processing ability and other related physiological traits compared to the other two species. L. chinense Mill. was the most tolerant to all levels of drought.  In contrast, L. yunnanense Kuang & A. M. Lu was more affected by water supply and had the lowest resistance to drought stress.  These findings would provide some important information regarding genetic resources for future forest tree improvement in relation to drought tolerance. 

    The tea geometrid Ectropis obliqua is one of the most serious leaf-feeding insect pests in tea (Camellia sinensis) in East Asia. Although several volatile chemicals emitted from tea plants have been reported to be attractive to E. obliqua moths, no synthetic attractants for E. obliqua moths have been developed. By measuring the behavioral responses of the moth to a series of chemicals in the lab, we found that a blend containing a ternary mixture containing (Z)-3-hexenal, (Z)-3-hexenyl hexanoate and benzyl alcohol clearly attracted to E. obliqua moths of both sex and that (Z)-3-hexenyl acetate could enhance the attractiveness of the ternary blend. Moreover, we found that the volatiles emitted from the plant-E. obliqua larva complex have the same attractiveness as: 1) the blend of volatiles containing the ternary mixture and 2) the blend containing (Z)-3-hexenyl acetate plus the ternary mixture to both male and female moths. In a field bioassay, more male moths were observed on traps that were baited with the blend containing (Z)-3-hexenyl acetate plus the ternary mixture than on control traps. Our study raises the tantalizing possibility that synthetic blends could be deployed as attractants for pests in the field.

To better understand the effects of plastic film mulching on soil greenhouse gases (GHGs) emissions, we compared seasonal and vertical variations of GHG concentrations at seven soil depths in maize (Zea mays L.) fields at Changwu station in Shaanxi, a semi-humid region, between 2012 and 2013. Gas samples were taken simultaneously every one week from non-mulched (BP) and plastic film-mulched (FM) field plots. The results showed that the concentration of GHGs varied distinctly at the soil-atmosphere interface and in the soil profile during the maize growing season (MS). Both carbon dioxide (CO2) and nitrous oxide (N2O) concentrations increased with increasement of soil depth, while the methane (CH4) concentrations decreased with increasement of soil depth. A strong seasonal variation pattern was found for CO2 and N2O concentrations, as compared to an inconspicuous seasonal variation of CH4 concentrations. The mean CO2 and N2O concentrations were higher, but the mean CH4 concentration in the soil profiles was lower in the FM plots than in the BP plots. The results of this study suggested that plastic film mulching significantly increased the potential emissions of CO2 and N2O from the soil, and promoted CH4 absorption by the soil, particularly during the MS.

    Information on the center of genetic diversity of soybean (Glycine max) will be helpful not only for designing efficient strategies for breeding programs, but also for understanding the domestication and origin of this species. Here, we describe an analysis of genetic diversity based on simple-sequence repeat (SSR) variations within a core collection of 2 111 accessions of Chinese soybean landraces. Prior to the diversity assessment, the geographic origin of each accession was mapped. The map was then divided into grids each 2.5° in latitude and 5° in longitude. We found two regions that had higher number of alleles (NA) and greater polymorphic information content (PIC) values than the others. These regions are adjacently located within grid position of 30°–35°N×105°–110°E, which includes the valley of the middle and lower reaches of the Wei River, and the valley of the upper reaches of the Hanjiang River. It was also observed that in many regions, genetic diversity decreased with the increase in distance from the center. Another region, in northern Hebei Province (115°–120°E×40°–42.5°N), was observed having higher diversity than any surrounding regions, indicating that this is a sub-center of soybean diversity. Based on the presented results, the domestication and origin of soybean are also discussed.

    Plant WRKY transcription factors are involved in various physiological processes, including biotic and abiotic stress responses, as well as developmental processes. In this study, the expression patterns of the WRKY68 protein during interactions between rice 4021 containing the bacterial blight resistance gene Xa21 and Xanthomonas oryzae pv. oryzae (Xoo) were investigated. A possible modified form of the WRKY68 protein appeared in the Xa21-mediated disease resistance response, and its expression levels were similar in compatible and incompatible responses, but differed significantly from that of the mock control treatment, suggesting that WRKY68 may be involved in the bacterial blight response in rice. To further understand WRKY68’s roles in the resistance signaling pathway, WRKY68 recombinant protein was expressed in Escherichia coli and a microscale thermophoresis analysis was performed to investigate the interactions between WRKY68 and cis-elements in crucial pathogenesis-related (PR) genes. The results showed that the WRKY68 protein binds to W-boxes in the PR1b promoter region, with an apparent dissociation constant of 25 nmol L^–1, while the binding between WRKY68 and PR10a was W-box independent. The results suggested that a possible modified form of the WRKY68 protein was induced during the interaction between rice and Xoo, which then regulated the activity of the downstream PR genes by binding with the W-boxes in the PR1b gene’s promoter region. Moreover, the constitutive transcription of the WRKY68 gene in dozens of rice tissues and the expression of the WRKY68 protein in leaves during all growth stages suggests that WRKY68 plays important roles in rice during normal growth processes.

A endochitinase gene (Tch) from the fungus Trichoderma viride was introduced into broccoli (Brassica oleracea var. italica) by Agrobacterium-mediated transformation. Sixty-eight putative transformants were obtained and the presence of the Tch gene was confirmed by both PCR and Southern blot analysis. RT-PCR analysis showed an accumulation of the transcript encoding the endochitinase protein in the transgenic plants. Using real-time quantitative PCR, the expression profiling of endochitinase gene was analyzed. Primary transformants and selfed progeny were examined for expression of the endochitinase using a fluorometric assay and for their resistance to the pathogenic fungi Botrytis cinerea and Rhizoctonia solani. The endochitinase activities in T0 in vitro plants, T0 mature plants and T1 mature plants were correlated with leaf lesions, and the transgenic line T618 had high endochitinse activities of 102.68, 114.53 and 120.27 nmol L–1 MU min–1 mg–1 protein in the three kinds of plants, respectively. The endochitinase activity showed a positive correlation with the resistance to the pathogens. Most transgenic T0 broccoli had increased resistance to the pathogens of B. cinerea and R. solani in leaf assays and this resistance was confirmed to be inheritable. These findings suggested that expression of the Tch gene from T. viride could enhance resistance to pathogenic fungi in Brassica species.

Timing of harvest is critical for mechanical picking in cotton production, especially in those regions with double cropping system. Appropriate and safe harvest aids will improve timing and facilitate harvest of cotton in the double cropping system. Three defoliants (dimethipin, thidiazuron, and thidiazuron-diuron) and one boll opener (ethephon) were included in this research. They were evaluated for their effects on defoliation, boll opening, seedcotton yield, seed quality, and fiber quality of field grown cotton when used alone or as a mixture in 2009 and 2010. Defoliation and/or boll opening were increased by all three defoliants and ethephon, especially by mixtures of a defoliant and ethephon. First harvest of seedcotton was significantly increased with defoliant-ethephon mixtures. No significant adverse effects were observed on boll weight, lint percentage, seed quality, and fiber properties. It was estimated that tank mixes of ethephon and one of the three defoliants can improve the adjusted gross revenue. Boll opening can be used as an alternative indicator for the adjusted gross revenue, because, it was linearly and positively correlated with the relative adjusted gross revenue and convenient in measurements. Wheat seedling growth was not affected by thidiazuron, whereas its seedling emergence, root dry weight, relative water content, and electrolyte leakage were adversely affected by dimethipin and thidiazurondiuron when concentration was above 340 and 100 g (a.i.) ha-1, respectively. 90% defoliation and 80% boll opening were observed with the high rate of thidiazuron-ethephon mixture, but no adverse effects on winter wheat. The results suggested that tank mixes of ethephon with thidiazuron can be used effectively and safely in the cotton-winter wheat double cropping system to improve yield without adverse effects on seed quality and fiber quality.

Mitogen activated protein kinases (MAPK) cascades based on protein phosphorylation play an important role in plant growth and development. In this study, we have identified 15 putative members of the wheat MAPK gene (TaMPK) family through an in silico search of wheat expressed sequence tags (EST) databases based on the presence of amino acid sequence of Arabidopsis and rice MAPKs. Phylogenetic analyses of MAPKs from wheat, rice and Arabidopsis genomes have classified them into seven subgroups (A, B, C, D, E, F, and G). Using the available EST information as a source of expression data, the MAPK family genes from Triticum aestivum were detected in diverse tissues. Further expression analysis of the MAPKs in NCBI EST database revealed that their transcripts were most abundant in callus (20%), followed by leaf (12%) and inflorescence (12%). Most MAPK family genes showed some tissue specificity.

This study was conducted at three rivers of the Chaohu Lake watershed during the summer season of 2008, aiming to investigate the diurnal variations of dissolved CH4 concentrations and emissions, as well as the dynamics of CH4 accumulation emission rates over consecutive 72 h. The results showed that CH4 concentrations in the Fengle, Hangbu, and Nanfei rivers ranged from 56.33-124.79, 160.82-341.03, and 213.49-716.81 nmol L-1, respectively, over a daily cycle; while the saturation of CH4 ranged from 188.72-418.07, 538.74-1 142.46, and 715.23-2 401.38%, respectively, which indicated that surface waters were in all cases oversaturated with respect to the atmosphere. An obvious diurnal variation pattern of the dissolved CH4 concentrations demonstrated a higher value during daytime but a lower value for night time. Additionally, the highest dissolved CH4 concentrations were detected in the Nanfei River which received substantial urban wastewater discharges. CH4 emissions measured with floating chambers ranged from 5.82-15.46, 5.77-8.41, and 13.51-49.25 mg C m-2 h-1 for the Fengle, Hangbu, and Nanfei rivers, respectively, over a daily cycle. Significantly higher CH4 emissions were also observed from the Nanfei River. The accumulative CH4 emissions for each river increased with time, while a decline trend on the accumulation rates was investigated over the consecutive 72 h.

Coccidiosis is caused by intra-cellular infection of Eimeria spp., which goes through a complex life cycle in the intestinal mucosa of infected hosts. Specific immunoglobulins (IgY) could be produced in egg yolk by immunizing hens with specific antigens. In the present study, we cloned the E. maxima gam56 gene, expressed the GST-GAM56 fusion protein and raised IgY to GST-GAM56 in hens. The anti-GST-GAM56 IgY antibody was isolated and used to treat chickens infected with E. maxima oocysts. Intramuscular injection of the antibodies provided minimal protection against parasite infection. However, oral dosing of the IgY 3 or 5 d after oocyst inoculation significantly improved body weight gain, reduced oocyst output and intestinal lesion score were reduced at 3 or 5 d after oocyst challenging, compared to the untreated control group. Our findings suggest that the IgY to gam56 could be an effective prophylactic or therapeutic agent against E. maxima infection in chickens and should have a practical application value.

The physical and chemical properties of the flours, starches, and modified starches of indica rice and japonica rice were investigated in this paper. Results showed that the swelling powers of flour, starch, and phosphate starch [substitution degree (DS)=0.065] of japonica rice were significantly higher than those (DS=0.065) of indica rice. The transmittance of modified starches was highest; and that of flours was lowest. The pasting property investigated with rapid visco analyzer (RVA) indicated that the peak viscosity and breakdown value of paste with high swelling power were high. Furthermore,the effect of protein and amylose content on pasting property were investigated. The results of rheological properties determined using rheological rheometer showed that at the same temperature, the storage modulus (G') of flour, starch,and modified starch of indica rice was higher than that of japonica rice. For each variety, the G' of flour was the highest,while the G' of modified starch was the lowest.

In the face of agricultural labor shortages, reducing labor and costs in rice production while meeting demand or increasing yield is crucial for sustainable agricultural development.  Utilizing crop straw boards and high-density seedling raising can reduce labor demand and enhance rice yield.  This study aimed to investigate the effects of seeding density and transplanting age on tillering patterns, panicle formation rates, and yield to determine optimal cultivation practices for maximizing rice yield.  Two-year field experiments were conducted in Sihong County, China, using the japonica rice variety Nanjing 5718.  Five seeding densities (150–350 g/tray) and four transplanting ages (10–25 days) were evaluated to assess their impact on tillering patterns, panicle formation rates, and yield.  Innovative crop straw boards were employed to enhance planting efficiency and reduce dependence on seedling-raising soil.  This approach also lessened tillage layer destruction, promoting sustainable practices.  The results indicated that increasing seeding density significantly altered tillering and panicle formation patterns, reducing the occurrence and panicle formation rates of lower-position tillers.  Although the occurrence of middle and high-position tillers increased, the overall number of panicles per hill decreased, especially at higher densities, negatively affecting yield.  Reducing transplanting age promoted the emergence and panicle formation of lower-position tillers, mitigating these negative effects.  Specifically, compared to traditional methods (150 g/tray, 20-day seedlings), the higher seeding density (300 g/tray) and shorter transplanting age (15-day seedlings) increased total panicle number by 3.79–4.73% and yield by 3.38–5.05%.  Combining higher seeding densities with reduced transplanting ages offers significant advantages over conventional practices by enhancing resource utilization, improving tillering efficiency.  These findings provide actionable recommendations for optimizing rice cultivation practices and contribute to sustainable agricultural development.