Correlation Analysis between Well-cellar Early Transplanting of Robust Seedlings and Diseases in Shiyan Tobacco-growing Area

[Objectives]The paper was to investigate the relationship between the well-cellar early transplanting of robust seedlings and the prevalence of diseases in the Shiyan tobacco-growing area.[Methods]The relationship between disease occurrence and meteorological factors during the field growth period was examined by analyzing the prevalence of flue-cured tobacco virus diseases,brown spot,and total disease in the Shiyan tobacco-growing area before(2013-2017)and after(2018-2022)the well-cellar early transplanting of robust tobacco seedlings.[Results]The implementation of a well-cellar early transplanting technique of robust seedlings resulted in a reduction in the average incidence of tobacco virus disease,brown spot,and total disease by 0.83%,8.85%,and 7.91%,respectively,in comparison to the incidence observed prior to early transplanting.These findings suggest that early transplanting can significantly reduce the incidence of flue-cured tobacco diseases.Prior to the well-cellar early transplanting of robust tobacco seedlings,there was a significant(including highly significant)positive correlation between the incidence of brown spot and total disease and precipitation in August and September.The incidence of brown spot and total disease in tobacco plants was found to be significantly positively correlated with May precipitation and significantly negatively correlated with May sunshine hours following the well-cellar early transplanting of robust seedlings.The advancement of the transplanting period by 20 d resulted in a reduction in the growing period of tobacco plants in the field under autumn rains(late August to November)in western China.This effectively circumvented the suitable conditions for disease occurrence and can reduce the incidence of disease.[Conclusions]This study offers a framework for enhancing the quality and efficiency of flue-cured tobacco production in the northwest tobacco-growing area of Hubei.

Chondroitinase ABC combined with Schwann cell transplantation enhances restoration of neural connection and functional recovery following acute and chronic spinal cord injury

Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties.A the Food and Drug Administration-approved Phase I clinical trial has been conducted to evaluate the safety of transplanted human autologous Schwann cells to treat patients with spinal cord injury.A major challenge for Schwann cell transplantation is that grafted Schwann cells are confined within the lesion cavity,and they do not migrate into the host environment due to the inhibitory barrier formed by injury-induced glial scar,thus limiting axonal reentry into the host spinal cord.Here we introduce a combinatorial strategy by suppressing the inhibitory extracellular environment with injection of lentivirus-mediated transfection of chondroitinase ABC gene at the rostral and caudal borders of the lesion site and simultaneously leveraging the repair capacity of transplanted Schwann cells in adult rats following a mid-thoracic contusive spinal cord injury.We report that when the glial scar was degraded by chondroitinase ABC at the rostral and caudal lesion borders,Schwann cells migrated for considerable distances in both rostral and caudal directions.Such Schwann cell migration led to enhanced axonal regrowth,including the serotonergic and dopaminergic axons originating from supraspinal regions,and promoted recovery of locomotor and urinary bladder functions.Importantly,the Schwann cell survival and axonal regrowth persisted up to 6 months after the injury,even when treatment was delayed for 3 months to mimic chronic spinal cord injury.These findings collectively show promising evidence for a combinatorial strategy with chondroitinase ABC and Schwann cells in promoting remodeling and recovery of function following spinal cord injury.

Relevant clinical factors for early extubation in living-donor liver transplantation: A single-center retrospective cohort study

BACKGROUND Clinical guidelines for early extubation after liver transplantation remain lacking,with significant variations in the rates of early extubation across transplantation centers.AIM To identify clinical factors,including the use of epidural analgesia,associated with early extubation in living-donor liver transplantation(LDLT).METHODS The medical records of LDLT recipients were analyzed in this study,categorizing them based on extubation timing as delayed(leaving the operating room without extubation)or early(tracheal tube removed immediately after surgery).A multivariate binary logistic regression analysis was performed.Subgroup analysis was conducted,excluding patients contraindicated for epidural analgesia owing to significant coagulopathy.RESULTS Total of 159 patients,93(58.5%)underwent early extubation.Relevant clinical factors of early extubation were shorter anhepatic time[adjusted odds ratio(OR)=0.439,95%confidence interval(CI):0.232-0.831;P=0.011],absence of high-dose vasoactive drug use at the end of surgery(OR=0.235,95%CI:0.106-0.519;P<0.001),and the use of epidural analgesia(OR=15.730,95%CI:1.919-128.919;P=0.010).In a subgroup analysis of 67 patients,epidural analgesia remained a relevant clinical factor for early extubation(adjusted OR=19.381,95%CI:2.15-174.433;P=0.008).CONCLUSION Shorter anhepatic time,absence of high-dose vasoactive drug use at the end of surgery,and the use of epidural analgesia are relevant clinical factors of early extubation following LDLT.

Macrophage polarization in cardiac transplantation:Insights into immune modulation and therapeutic approaches

The role and regulatory mechanisms of macrophage polarization in cardiac transplantation have gained significant attention.Macrophages can polarize into either the M1(pro-inflammatory)or M2(anti-inflammatory)phenotype in response to environmental cues.M1 macrophages facilitate transplant rejection by releasing inflammatory mediators and activating T cells,whereas M2 macrophages support graft survival by secreting antiinflammatory factors and promoting tissue repair.Mitochondrial quality control regulation plays a crucial role in macrophage polarization,which may influence graft survival and immune responses.This review provides an overview of the current understanding of mitochondrial quality control-regulated macrophage polarization in cardiac transplantation,its effects on graft outcomes,and potential therapeutic strategies to modulate this process to enhance transplant success rates.The review was conducted by systematically analyzing recent studies and integrating findings from key research articles to synthesize a comprehensive understanding of this emerging field.

Advances in the treatment of autism spectrum disorder:Wharton jelly mesenchymal stem cell transplantation

BACKGROUND Autism spectrum disorder(ASD)is a complex neurodevelopmental disorder with multifaceted origins.In recent studies,neuroinflammation and immune dysregulation have come to the forefront in its pathogenesis.There are studies suggesting that stem cell therapy may be effective in the treatment of ASD.AIM To evolve the landscape of ASD treatment,focusing on the potential benefits and safety of stem cell transplantation.METHODS A detailed case report is presented,displaying the positive outcomes observed in a child who underwent intrathecal and intravenous Wharton’s jelly-derived mesenchymal stem cells(WJ-MSCs)transplantation combined with neurorehabilitation.RESULTS The study demonstrates a significant improvement in the child’s functional outcomes(Childhood Autism Rating Scale,Denver 2 Developmental Screening Test),especially in language and gross motor skills.No serious side effects were encountered during the 2-year follow-up.CONCLUSION The findings support the safety and effectiveness of WJ-MSC transplantation in managing ASD.

Providing care for kidney transplant recipients:An overview for generalists

Kidney transplantation is the preferred treatment for patients with advanced chronic kidney disease and end-stage kidney disease,offering superior quality of life and survival compared to dialysis.This manuscript provides an updated overview of post-transplant care,highlighting recent advancements and current practices to assist generalists in managing these patients.It covers key areas such as immunosuppression strategies,drug interactions,and the management of transplant-specific acute kidney injury.The focus includes the use of sodium-glucose cotransporter-2 inhibitors and cell-free DNA monitoring for evaluating allograft health and immune-mediated injury.The manuscript reviews the fundamentals of immunosuppression,including both induction and maintenance therapies,and underscores the importance of monitoring kidney function,as well as addressing hypertension,diabetes,and infections.It also provides recommen-dations for vaccinations and cancer screening tailored to kidney transplant reci-pients and emphasizes lifestyle management strategies,such as exercise and so-dium intake,to reduce post-transplant complications.

Internal biliary diversion using appendix during liver transplantation for progressive familial intrahepatic cholestasis type 1:A case report

BACKGROUND Progressive familial intrahepatic cholestasis type 1(PFIC-1)is a genetic cholestatic disease causing end-stage liver disease,which needs liver transplantation(LT).Simultaneous biliary diversion(BD)was recommended to prevent allograft steatosis after transplantation,while increasing the risk of infection.Here,an attempt was made to perform BD using appendix to prevent bacterial translocation after LT.CASE SUMMARY An 11-month-old boy diagnosed with PFIC-1 received ABO compatible living donor LT due to refractory jaundice and pruritus.His mother donated her left lateral segment with a graft-to-recipient weight ratio of 2.9%.Internal BD was constructed during LT using the appendix by connecting its proximal end with the intrahepatic biliary duct and the distal end with colon.Biliary leakage was suspected on the 5th day after transplantation and exploratory laparotomy indicated biliary leakage at the cutting surface of liver.The liver function returned to normal on the 9th day post-operation and maintained normal during the 15-month follow-up.Cholangiography at 10 months after transplantation confirmed the direct secretion of bile into colon.Computerized tomography scan(4 months and 10 months)and liver biopsy(10 months)indicated no steatosis in the allograft.No complaint of recurrent diarrhea,infection or growth retardation was reported during follow-up.CONCLUSION Internal BD using appendix during LT is effective in preventing allograft steatosis and post-transplant infection in PFIC-1 recipients.

Effect of kidney transplantation on sexual dysfunction in patients with end stage renal disease:A systematic review

BACKGROUND End-stage renal disease(ESRD)is associated with a multitude of physical,psychological,and social health challenges,including a profound impact on sexual and reproductive health.Among males with ESRD,erectile dysfunction(ED)is highly prevalent due to factors such as underlying comorbidities,including diabetes and hypertension,and the physiological effects of long-term dialysis.Kidney transplantation(KTx)has been proposed as a potential intervention to mitigate the effects of ED by restoring renal function and improving hormonal balance.However,the evidence surrounding the effectiveness of KTx in improving sexual function,specifically erectile function(EF),remains inconclusive.This systematic review and meta-analysis aim to evaluate the effects of KTx on sexual dysfunction(SexDys),particularly ED,in male ESRD patients.AIM To evaluate the benefits and potential harms of KTx compared to other forms of renal replacement therapy in improving EF in adult males with ESRD,assessed using the international index of EF(IIEF),to survey the prevalence of SexDys in this population,and to assess the correlation between various factors and SexDys through regression analysis.METHODS A systematic search of PubMed,EMBASE,Cochrane Library,Scopus,Clinical-Trials.gov,and Google Scholar was conducted,following the PRISMA 2020 guidelines.Prospective and retrospective cohort studies,as well as cross-sectional studies assessing EF pre-and post-transplantation,were included.These studies used validated tools such as the IIEF to measure EF.Meta-analyses were performed using a random-effects model to estimate standardized mean differences(SMD)and hazard ratios(HR)with 95%confidence intervals(CI).Heterogeneity was assessed using the I²statistic,and publication bias was evaluated with a funnel plot and the Egger’s test.RESULTS A total of 2419 studies were identified,with 362 abstracts screened and 193 full-text articles reviewed.Ultimately,11 studies were included for qualitative analysis and 7 for quantitative synthesis.The random effects model for SMD yielded a combined estimate of 0.43(95%CI:-0.20-1.07),indicating a small but non-significant improvement in EF post-transplantation.The heterogeneity across studies was substantial(I²=90%),reflecting significant variability in outcomes.Subgroup analysis showed greater improvements in EF among living-donor transplant recipients compared to those receiving organs from deceased donors.Despite this trend,the overall result for changes in EF was not statistically significant(P=0.15).Additionally,the combined HR from the meta-analysis was 2.87(95%CI:1.76-4.69),suggesting that KTx significantly increases the likelihood of improved EF,though variability between studies persisted(I²=63%).CONCLUSION While KTx offers some promise for improving EF in male ESRD patients,the overall evidence remains inconclusive due to high heterogeneity between studies and a lack of statistical significance in the combined results.Despite this,individual studies suggest that KTx may lead to significant improvements in EF for certain subgroups,particularly living-donor recipients.Future research should focus on larger,well-designed cohort studies with standardized outcome measures to provide more definitive conclusions.Addressing SexDys as part of routine care for ESRD patients undergoing KTx is crucial to improving their overall quality of life.However,adjunct therapies such as phosphodiesterase type 5 inhibitors may be necessary for those who do not experience adequate improvements post-transplantation.

Protective effects of autologous bone marrow-derived mesenchymal stem cell transplantation on acute radioactive enteritis in Beagle dogs

BACKGROUND Radiation enteritis is a common complication of radiation therapy in which the surrounding normal intestinal tissue is damaged by ionising radiation,and there is no standard pharmacological prophylaxis or treatment regimen available.Mesenchymal stem cell transplantation can be used for radiation protection and the treatment of acute radiation injury,but its therapeutic mechanism of action remains unclear.AIM To investigate the protective effects of autologous bone marrow-derived mesenchymal stem cell(ABMSC)transplantation on radiation-induced intestinal injury.METHODS A model of acute radioactive enteritis was established in dogs by applying abdominal intensity-modulated radiation at a single X-ray dose of 12 Gy.ABMSCs were transplanted into the mesenteric artery with the technology of femoral artery puncture and DSA imaging two days after radiation.Visual and histopathological changes of the experimental dogs were observed.Different kinds of cytokines from intestinal samples were tested using Quantibody Canine Cytokine Array method.Enzyme-linked immunosorbent assay(ELISA)was also used to evaluate the cytokines changes in serum.RESULTS The ABMSCs group showed significant improvements in survival status compared with the blank and saline treatment groups.Histological observations revealed that the former had lower histological scores than the later after treatment(P<0.05).Compared to the control groups,interleukin(IL)-10 and monocyte chemotactic protein(MCP)-1 from intestinal samples showed a remarkable increase and ELISA of serum samples proved higher secretion of the two target cytokines in the ABMSCs group(P<0.05).CONCLUSION Our data suggest that transplantation of ABMSCs promotes intestinal recovery after acute radioactive injury in Beagle dogs.The cytokines of IL-10 and MCP-1 might play an important role in this process.

Study on Sowing Date for Mechanicaltransplanting Rice under Wheat-Rice Cropping System in Chengdu Basin

Nurturing sturdy mechanical-transplanting seedlings is the key to achieve high yield using mechanical-transplanting technology under wheat-rice cropping conditions in Chengdu Basin. In this study, super hybrid rice II You 602 was adopted as experimental material, to investigate the effects of sowing date on seedling growth,transplanting quality, growth process and yield of mechanical-transplanting seedlings in wheat-rice cropping region of Chengdu Basin, thus exploring supporting high-yield cultivation techniques for mechanical-transplanting technology in Chengdu Basin, Results showed that the appropriate sowing date for mechanical transplanting in wheatrice cropping region of Chengdu Basin was April 10-15, and the appropriate seedling age was 45-50 d, which led to the highest yield of mechanical-transplanting seedlings. Although postponing sowing was conducive to improving transplanting quality and increasing the percentage of earbearing tillers, it would result in lagged group growth, poor spike quality and reduced effective number of panicles, grain number, seed-setting rate, 1 000-seed weight and other yield components, thus declining the yield. Yield reduction rate would be above 10% with sowing date postponed by 15 d.

Research on Potted-Tray Grown Rice Seedling Transplanting by Machine

[Objective] In order to cultivate seedlings that are adaptable to farming system and transplanter, the technology for transplanting potted-tray grown rice seedlings with machine was introduced and studied. [Method] The transplanter-spe-cific seedlings were cultivated with potted-tray, bowl-shaped blanket tray and soft plastic flat plate respectively. The seeding rate and 20-50-day-old seedling height were investigated for the 3 sowing patterns. After the transplanting, the missing transplanting rate, upright seedling rate, seedling injury rate and green-returning pe-riod were investigated. [Result] Nursing seedlings with potted-tray had the advan-tages of saving seeds, high sowing precision, high seedling rate and high seedling rate. The 20-40-day-old seedlings had relatively high leaf age, seedling height and root number. However, 40 d after the transplanting, the growth of seedlings was slowed. The quality difference was smal est among the 20-day-old seedlings that were nursed with 3 different patterns, but since then the quality advantage of pot-ted-tray grown seedlings had been more and more prominent. There was smal dif-ference in quality among the 30-day-old seedlings. However, for the seedlings that were older than 40 d, the transplanting quality of potted-tray grown seedlings was higher than that of bowl-shaped blanket tray grown seedlings and soft plastic flat plate grown seedlings. In addition, the green-returning period of the potted-tray grown seedlings was significantly shortened. [Conclusion] Compared to the bowl-shaped blanket tray grown seedlings and soft plastic flat plate grown seedlings, the potted-tray grown seedlings were more suitable to transplant by machine in the wheat-rice double cropping areas of Chengdu Plain.

Effect of Transplanting Density on Rice Yield,Nitrogen Uptake and ^(15)N-fertilizer Fate

[Objective] The aim of this study was investigated the rice yield, nitrogen uptake and ^15-fertilizer fate at different transplanting density to provide scientific ba- sis for improving the yield of rice and applying reasonably fertilizer. [Method] A field experiment was carried out to study the effect of different transplanting density on rice yield, nitrogen （N） absorption, sources of N uptake by rice and the N balance in the plant-soil systems by using ^15-labelled urea. [Result] There were no significant differences in rice yields and total N uptakes by rice between treatments 30 cm × 30 cm and 40 cm × 40 cm, but the yield of rice and total N absorption in the two treatments were remarkably higher than those in 50 cm × 50 cm treatment. The amounts of total N uptake by rice were in the range of 112.3-162.7 kg/hm2 in the three transplanting densities. The result showed that about 1/3 of the total N uptake by rice was supplied by application fertilizer and the other 2/3 was obtained from the soil N pool. The ^15N-labelled urea absorbed by rice, residual in soil and lost accounted for 16.3%-26.1%, 17.0%-20.9% and 53.0%-66.7% of the total fertilizer, respectively. A great deal of ^15N-labelled urea was lost during the rice growing season. [Conclusion] Considering the rice yield and environmental protection, the transplanting density of 30 cm×30 cm was recommended in the hilly area of Sichuan basin in the southwest China.

Effects of Different Transplanting and Harvest Dates on Yield and Quality of Flue-cured Tobacco Leaves

In this study,the effects of nine different combinations of transplanting and harvest dates on yield and quality of flue-cured tobacco leaves were investigated.The results showed that different combinations of transplanting and harvest dates had few effects on growth period and agronomic characters of tobacco plants but exerted remarkable effects on economic characters and chemical composition of flue-cured tobacco leaves.With the postponing of transplanting stage,output value of flue-cured tobacco leaves increased.Output value of flue-cured tobacco leaves in C1treatment（normal harvest） was higher than that in C2（harvest 7 d later） and C3（harvest 14 d later） treatments.Different combinations of transplanting and harvest dates had significant effects on chemical composition of flue-cured tobacco leaves,which exhibited no obvious law.Overall,flue-cured tobacco leaves in T3C1treatment（transplanting 14 d earlier,normal harvest） displayed excellent performance compared with other treatments.

Effects of Transplanting Density on Yield Formation Characteristics of Purple Rice

Liangtianzi 1 was used as a material to study the effects of transplanting density on the yield formation characteristics of purple rice. The results showed that the whole growth period of Liangtianzi 1 was 146 d. Its biomass yield was above 10 t/hm^2, while its economic yield was only about 3 t/hm^2. Transplanting density had a large impact on the number of effective panicles, number of grains par panicle, seed setting rate and yield of purple rice variety. In this study, the planting spacing of 20.0 cm × 20.0 cm gained the highest yield, 3.63 t/hm^2. Key techniques for high-yielding cultivation of Liangtianzi 1 remain to further research.

Tillering Characteristics of Different Varieties of Double-season Rice under Different Mechanical Transplanting Modes

A total of 8 early-season and late-season rice varieties with different growth periods were selected, and their tillering characteristics under wide-narrow row and equal row .transplanting modes were studied. The results showed that the length of slow growth phase was related to the performance of transplanter; the ef- fect of mechanical transplanting on tillering of early-season rice was greater than that of late-season rice; Compared with late-season rice, early-season rice showed later tillering and longer tillering period; the tiller number per plant and effective panicle number per plant differed greatly among different varieties of double-season rice; under the condition of same transplanting density, the tillers of rice under wide- narrow row transplanting mode appeared rapidly and disappeared slowly, and wide- narrow row transplanting mode improved tillering, effective panicle number and yield of rice; different varieties of double-season rice showed different adaptability to me- chanical transplanting, and the varieties with short growth period, strong tilledng a- bility and more effective panicles per plant were more suitable for mechanical trans- planting; the effect of mechanical transplanting on rejuvenation of rice could be im- proved by improving the performance of transplanter.

Major Physiological Characters of Different Double Cropping Rice Varieties by Different Mechanical Transplanting Methods

The research selected 16 rice varieties（8 early and 8 late double-cropping rice） by mechanical transplanting modes as per equivalent row and wide-narrow row to explore yield and physiological traits in order to provide references for selection of rice variety suitable for mechanical transplanting. The results showed that yields of early and late rice improved by 2.90% and 2.73% by mechanical transplanting as per equivalent row and wide-narrow row respectively. Besides, leaf area index in the treatment as per wide-narrow row was higher compared with the treatment as per equivalent row, as well as average photosynthetic potential which grew by 0.92%,3.99% and 5.64% of early from tillering-peak stage to mature stage and 3.46%,7.09% and 6.79% of late rice. Furthermore, by mechanical transplanting as per wide-narrow row, SPAD value, and root activity performer higher, as well as the number of differentiated branch and glumous flowers, but degradation rate showed lower. In addition, with mechanical transplanting the same, early rice Zhuliangyou819 and late rice Fengyuanyou 299 took advantages in yield, which can be priorities for mechanical transplanting in double-cropping areas in Jiangxi Province.

Effects of Mechanized Transplanting and Fertilization Mode on Population Growth and Development of Male Parent in Seed Production of Hybrid Rice

In order to study the effects of mechanized transplanting and fertilization mode on population growth and development of the male parent in seed production of hybrid rice, three male parents, Huazhan, Shuhui 527 and R9311 were selected as materials. The male parents were transplanted by rice transplanter with two kinds of line spacing design, six lines with equal row spacing （20/25 cm x 30 cm） and wide and narrow spacing （20/25 cm x 40, 20 cm）, and artificial transplanting with equal row spacing （20/25 cm x 30 cm） was set as the control. The three fer- tilization modes were applying for one, two and three times. The flowering stage and panicle-spikelet structure of the male parent were investigated. The results showed that the effects of mechanized transplanting and fertilization mode were little on the duration from seeding to heading; the panicles and spikelets of the three male parents were significantly increased by mechanized transplanting. The tiller number was increased by mechanized transplanting and fertilizing for two and three times. Wide and narrow spacing by machine planting and fertilizing for three times were suitable for Huazhan, which significantly increased the number of spikelets per unit area. Furthermore, the number of spikelets per unit area of Shuhui 527 and R9311 were significantly increased by mechanized transplanting and fertilizing for three times.

Effects of Farming and Seedling-raising Methods on Population Growth and Grain Yield of Mechanized Transplanting Rice

The effects of farming method, rice variety and seedling-raising method were studied on the population growth quality and grain yield of the mechanized transplanting rice by way of three-factor split plot design. The results showed that the no-tillage mechanical transplanting treatment was poorer than the conventional mechanical transplanting treatment in transplanting quality in general, but the former was similar to the latter in population growth quality. In regard to grain yield, the no-tillage mechanical transplanting treatment was lower than the conventional me- chanical transplanting treatment. Raising both pot-mat seedling and plastic-tray seedling did not make much difference in population growth and grain yield of mechanized transplanting rice, so both of the seedling-raising methods can be adopted according to practical conditions.

Effects of Plant Spacing and Finger Sticking Area Settings for Machine Transplanting on Yield of Double-season Early Rice

The effects of rice transplanters＇ transplanting settings（plant spacing and finger sticking area） on rice yield were investigated in two early-season rice cultivars：hybrid rice cultivar（Zhuliangyou 819） and conventional rice cultivar（Zhongjiazao 17）.The results showed that,different transplanting settings resulted in different numbers of transplanted basic seedlings,and the rice yield was significantly correlated with the number of transplanted basic seedlings.The number of transplanted basic seedlings increased with the decrease of plant spacing and the increase of finger sticking area.The rate of lost hills of machine transplanting decreased with the increase of finger sticking area.The leaf area index and amount of dry matter accumulation were highly correlated with the number of transplanted basic seedlings.The average yield of the rice transplanted with a plant spacing of11.5 cm was higher than that with a plant spacing of 13.8 cm.In the field transplanted with the rice under the plant spacing of 13.8 cm,the rice yield increased with the increase of finger sticking area,and the finger sticking area of 2.23 cm2 showed the highest rice yield of 8 174.16 kg/hm2 of Zhuliangyou 819 and 7 925.54kg/hm2 of Zhongjiaozao17.In the field transplanted with the rice under the plant spacing of 11.5 cm,the rice yield was the highest with the finger sticking area of 1.83 cm2,and then decreased with the large finger sticking area.Under the plant spacing of 11.5 cm,the highest rice yields of Zhuliangyou 819 and Zhongjiaozao17 were 8 492.94 kg/hm2 and 8 000.23 kg/hm2,respectively.Therefore,the preferred machine transplanting settings for double-season early rice are a plant spacing of11.5 cm and a finger sticking area of 1.83 cm2,while the finger sticking area should be increased to 2.23 cm2 for conventional rice cultivars.

Study on Multiplication, Rooting and Transplanting of Tissue Culture Plantlets of Rhododendron chrysanthum Pall

[Objective] This study aimed to shorten the multiplication culture and root- ing culture periods of Rh. chrysanthum Pall. [Method] The Rh. chrysanthum Pall tis- sue culture plantlets collected from Changbai Mountain were used as material, and the effects of different hormone combinations and coconut milk on the proliferation and differentiation of Rh. chrysanthum Pall tissue culture plantlets were investigated. In addition, the rooting medium and transplanting matrix for Rh. chrysanthum Pall tissue culture plantlets were explored. [Result] The medium composed of modified MS, iBA （3 mg/L） and ZT （1.5 mg/L） was the optimum medium for subculture mul- tiplication of Rh. chrysanthum Pall tissue culture plantlets. The multiplication multiple and average plant height were significantly improved by adding coconut milk into the medium （150 mg/L）. [Conclusion] For Rh. chrysanthum Pall tissue culture plantlets, the optimum rooting culture medium was composed of modified MS （1/4） and IBA （5.0 mg/L）, and the tissue culture plantlets began to root 8 d after the inoculation. The root induction treatment was carried out after a 15-d sand culture, and the suitable matrix was composed of tufty soil, humus soil and perlite （2：1：1） with a survival rate of 95.66%.