The haplotype-resolved T2T reference genome highlights structural variation underlying agronomic traits of melon

Melon(Cucumis melo L.)is an important vegetable crop that has an extensive history of cultivation.However,the genome of wild and semi-wild melon types that can be used for the analysis of agronomic traits is not yet available.Here we report a chromosome-level T2T genome assembly for 821(C.melo ssp.agrestis var.acidulus),a semi-wild melon with two haplotypes of∼373 Mb and∼364 Mb,respectively.Comparative genome analysis discovered a significant number of structural variants(SVs)between melo(C.melo ssp.melo)and agrestis(C.melo ssp.agrestis)genomes,including a copy number variation located in the ToLCNDV resistance locus on chromosome 11.Genome-wide association studies detected a significant signal associated with climacteric ripening and identified one candidate gene CM_ac12g14720.1(CmABA2),encoding a cytoplasmic short chain dehydrogenase/reductase,which controls the biosynthesis of abscisic acid.This study provides valuable genetic resources for future research on melon breeding.

T-S Fuzzy Remote Sensing Monitoring Model of Snail Distribution by Landsat 8 and Sentinel 2 Data

Approximately half of the world’s population is at the risk of at least one vector-borne parasitic disease.The survival of intermediate hosts of vector-borne parasitic diseases is governed by various environmental factors,and remote sensing can be used to characterize and monitor environmental factors related to intermediate host breeding and reproduction,and become a powerful means to monitor the vector-borne parasitic diseases.Schistosomiasis is a parasitic disease that menaces human health.Oncomelaniahupensis(snail)is the unique intermediate host of Schistosoma,so monitoring and controlling the number of snail is key to reduce the risk of schistosomiasis transmission.In this paper,Landsat 8 OLI and Sentinel 2 MSI data had been used to obtain the environmental factors(vegetation,soil,temperature,terrain et al.),which are related to the multiplying and transmission of intermediate host.Then this study used T-S(Takagi-Sugeno)Fuzzy RS model to establish a new suitable index membership function due to the different RS data,and a long time series monitoring of snail distribution in Dongting Lake from 2014 to 2018 was achieved.A comparative analysis was performed to validate the predicted results against the field survey data.The results demonstrated the accuracy of the developed model in predicting the distribution of snails.

Control of flowering and inflorescence architecture in tomato bysynergistic interactions between ALOG transcription factors

Inflorescences are flower-bearing shoots that originate from pools of stem cells in shoot apical meristems (SAM).Inflorescence architecture is determined by a process of meristem maturation,during which stem cell fate switches from a vegetative to a reproductive growth program.A major factor in plant reproductive success in nature and yield in agriculture is the number of branches and flowers on inflorescences (Kobayashi and Weigel,2007;

Estimating leaf water content at the leaf scale in soybean inoculated with arbuscular mycorrhizal fungi from in situ spectral measurements

Leaf water content(LWC)of crops is a suitable parameter for evaluation of plant water status and arbuscular mycorrhizal effect on the host plant under drought stress.Remote sensing technology provides an effective avenue to estimate LWC in crops.However,few LWC retrieval models have been developed specifically for the arbuscular mycorrhizal inoculated crops.In this study,soybean with inoculation and non-inoculation treatments were planted under the severe drought,moderate drought and normal irrigation levels.The LWC changes under different treatments at the 30 th,45 th and 64 th day after the inoculation were investigated,and the spectral response characteristics of inoculated and non-inoculated soybean leaves under the three drought stresses were analyzed.Five types of spectral variables/indices including:raw spectral reflectance(R),continuum-removed spectral reflectance(R C),difference vegetation index(DVI),normalized difference vegetation index(NDVI)and ratio vegetation index(RVI)were applied to determine the best estimator of LWC.The results indicate that LWC decreased as the aggravating of drought stress levels.However,LWC in inoculated leaves was higher than that in the counterparts under the same drought stress level,and the values of raw reflectance measured at inoculated leaves were lower than the non-inoculated leaves,especially around 1900 nm and 1410 nm.These water spectral features were more evident in the corresponding continuum-removed spectral reflectance.The newly proposed DVI C(2280,1900)index,derived from the continuum-removed spectral reflectance at 2280 nm and the raw spectral reflectance at 1900 nm in DVI type of index,was the most robust for soybean LWC assessment,with R 2 value of 0.72(p<0.01)and root mean square error(RMSE)and mean absolute error(MAE)of 2.12%and 1.75%,respectively.This study provides a means to monitor the mycorrhizal effect on drought-induced crops indirectly and non-destructively.