Appropriate supply of irrigation and nitrogen produced higher yields of cherry tomatoes

Accurate irrigation and nitrogen application are essential for promoting the growth and yield of cherry tomatoes.In investigating the effects of irrigation and nitrogen on the growth,photosynthesis,and yield of cherry tomatoes,nine treatments including three levels of both irrigation and nitrogen were conducted over two growing seasons.Transverse stem diameter and horizontal stem diameter had the best performance at the irrigation level of 75%evaporation(E_(p)),although their responses to nitrogen were different for the two years.Plant height increased with the increase of irrigation and nitrogen.Plant dry matter(PDM)was significantly affected by irrigation and nitrogen interaction.The lowest PDM was found in the highest proportion of root dry matter,which occurred under low nitrogen level.The net photosynthetic rate(Pn)and transpiration rate enhanced with the increase of irrigation.Medium nitrogen showed promotion effect on all photosynthetic parameters in both growing seasons.Six of all fourteen indicators showed significant correlations with yield.Especially,single plant fruit number and PDM in 2018 Fall had significant positive direct effects on yield with the path coefficients of 0.648 and 1.159,while the significant direct path coefficients were 0.362 and 0.294 in Fruit dry matter and Pn for 2019 Spring,respectively.Based on the comprehensive evaluation of growth and yield by TOPSIS,the irrigation level of 75%E_(p) combined with medium nitrogen application produced higher yields by promoting the growth and photosynthesis of cherry tomatoes.It provides a strategy for water and nitrogen management of cherry tomatoes in Northwest China.

Efficient de novo assembly and modification of large DNA fragments

Synthetic genomics has provided new bottom-up platforms for the functional study of viral and microbial genomes.The construction of the large,gigabase(Gb)-sized genomes of higher organisms will deepen our understanding of genetic blueprints significantly.But for the synthesis and assembly of such large-scale genomes,the development of new or expanded methods is required.In this study,we develop an efficient pipeline for the construction of large DNA fragments sized 100 kilobases(kb)or above from scratches and describe an efficient method for“scar-free”engineering of the assembled sequences.Our method,therefore,should provide a standard framework for producing long DNA molecules,which are critical materials for synthetic genomics and metabolic engineering.

Determination of amount of irrigation and nitrogen for comprehensive growth of greenhouse cucumber based on multi-level fuzzy evaluation

In the northwestern part of China,rational and efficient management of irrigation and nitrogen significantly affects the intensive production of greenhouse cucumbers(Cucumis sativus L).To evaluate the effects of different combinations of water use and nitrogen(N)on yield,quality,and profitability of the greenhouse cucumbers that planted in 2018 Spring,nine combined treatments were applied.Results indicated the optimal irrigation and nitrogen demands for yield,quality and other indicators were different.The irrigation amount significantly affected the yield,and the yield gradually increased with increasing in irrigation.Single fruit weight(SFW)was significantly affected by the amount of irrigation,nitrogen and their interactions,and the higher amounts of N and irrigation were beneficial to the increase of SFW.The partial factor productivity of the applied N(PFPN)gradually increased with the nitrogen amount decline.Irrigation water use efficiency(IWUE)was closely related to the amount of irrigation.The higher irrigation amount would lead to the lower IWUE.When the amounts of irrigation and nitrogen were at an intermediate level,the content of vitamin C(VC)reached the maximum.As the amount of nitrogen was increased or irrigation was decreased,the Nitrate content(NC)would increase.Free amino acid(FAA)and NC followed a similar variation.When the amounts of irrigation and nitrogen both were at medium levels,the total soluble sugar concentration(TSSC)reached the highest.The multi-level fuzzy evaluation method was used to evaluate different indicators of cucumber.The weights of indicators in the first and second layer were determined by analytic hierarchy process(AHP)and entropy weight method,respectively.Then the fuzzy algorithm was used to comprehensively evaluate all the treatments.The evaluation results show that T4(irrigation,1957.6 m3/hm2;N,210 kg/hm2)is the best strategy for greenhouse cucumber irrigation and nitrogen management in the northwestern part of China.

Improving Na^(+)transport kinetics and Na^(+)storage of hierarchical rhenium-nickel sulfide(ReS_(2)@NiS_(2))hollow architecture by assembling layered 2D-3D heterostructures

Mixed metal sulfides have been widely used as anode material of sodium-ion batteries(SIBs)because of their excellent conductivity and sodium ion storage performance.Herein,ReS_(2)@NiS_(2)heterostructures have been triumphantly designed and prepared through anchoring ReS_(2)nanosheet arrays on the surface of NiS_(2)hollow nanosphere.Specifically,the carbon nanospheres was used as hard template to synthesize NiS_(2)hollow spheres as the substrate and then the ultrathin two-dimensional ReS_(2)nanosheet arrays were uniformly grown on the surface of NiS_(2).The internal hollow property provides sufficient space to relieve the volume expansion,and the outer two-dimensional nanosheet realizes the rapid electron transport and insertion/extraction of Na^(+).Owing to the great improvement of the transport kinetics of Na^(+),NiS_(2)@ReS_(2)heterostructure electrode can achieve a high specific capacity of 400 mAh/g at the high current density of 1 A/g and still maintain a stable cycle stability even after 220 cycles.This hard template method not only paves a new way for the design and construct binary metal sulfide heterostructure electrode materials with outstanding electrochemical performance for Na^(+)batteries but also open up the potential applications of anode materials of SIBs.