从头驯化:作物品种设计与培育的新方向

全球气候变化对农业生产带来了巨大挑战。在农业投入减少的前提下如何保障粮食生产持续稳步增长,满足人们吃饱、吃好的需求是亟需考虑的问题。培育高产、稳产、绿色、营养的新型作物品种仍然是解决该挑战的有效措施之一。作物新品种的培育高度依赖育种材料遗传多样性的拓宽和育种技术的创新。从头驯化是一种作物品种创新的全新育种策略,以具有某些优异性状的未驯化、半驯化植物作为底盘物种,通过农艺性状重新设计和驯化基因导入实现野生植物快速驯化,从而满足人类多样化需求。本文回顾了作物驯化、遗传改良历程,阐明了丰富作物多样性的必要性,强调野生植物丰富的遗传多样性对于拓展作物重新设计空间的重要价值,提出育种策略革新是加速作物育种的关键,探讨了通过从头驯化快速培育新型作物品种的可行性和发展前景。

基于自动识别系统和门控递归装置的港口流量预测模型

Water transportation today has become increasingly busy because of economic globalization.In order to solve the problem of inaccurate port traffic flow prediction,this paper proposes an algorithm based on gated recurrent units(GRUs)and Markov residual correction to pass a fixed cross-section.To analyze the traffic flow of ships,the statistical method of ship traffic flow based on the automatic identification system(AIS)is introduced.And a model is put forward for predicting the ship flow.According to the basic principle of cyclic neural networks,the law of ship traffic flow in the channel is explored in the time series.Experiments have been performed using a large number of AIS data in the waters near Xiazhimen in Zhoushan,Ningbo,and the results show that the accuracy of the GRU-Markov algorithm is higher than that of other algorithms,proving the practicability and effectiveness of this method in ship flow prediction.

Analysis of Water Quality Variation and Trend in the Ji'an Section of the Ganjiang River

Based on the monitoring data of water quality in the Ji'an section of the Ganjiang River from 2008 to 2018 by the Water Resources Monitoring Center of Ji'an City,single factor evaluation method,comprehensive pollution index method and seasonal Kendall test method were adopted to study and analyze the characteristics of surface water resources and the changing trend of water quality in the river section.The results show that the water quality in the Ji'an section of the Ganjiang River was generally good,and the water quality of each function zone reached the target requirement.The comprehensive pollution index was controlled between 0.21 and 0.40 over the years,and there was no significant change in time and space,and the water quality was relatively stable.The dissolved oxygen and permanganate index tended to improve,and there was no change in five-day biochemical oxygen demand,while ammonia nitrogen and total phosphorus showed an upward trend.The water quality as a whole showed a trend of deterioration.By discussing the influencing factors of the characteristic pollutants,the causes of water quality in the Ji'an section of the Ganjiang River were further analyzed.It is suggested to strengthen the supervision and control of non-point source and point source pollution.

Complex genetic architecture underlying the plasticity of maize agronomic traits

Phenotypic plasticity is the ability of a given genotype to produce multiple phenotypes in response to changing environmental conditions.Understanding the genetic basis of phenotypic plasticity and establishing a predictive model is highly relevant to future agriculture under a changing climate.Here we report findings on the genetic basis of phenotypic plasticity for 23 complex traits using a diverse maize population planted at five sites with distinct environmental conditions.We found that latituderelated environmental factors were the main drivers of across-site variation in flowering time traits but not in plant architecture or yield traits.For the 23 traits,we detected 109 quantitative trait loci(QTLs),29 for mean values,66 for plasticity,and 14 for both parameters,and 80%of the QTLs interacted with latitude.The effects of several QTLs changed in magnitude or sign,driving variation in phenotypic plasticity.We experimentally validated one plastic gene,ZmTPS14.1,whose effect was likely mediated by the compensation effect of ZmSPL6 from a downstream pathway.By integrating genetic diversity,environmental variation,and their interaction into a joint model,we could provide site-specific predictions with increased accuracy by as much as 9.9%,2.2%,and 2.6%for days to tassel,plant height,and ear weight,respectively.This study revealed a complex genetic architecture involving multiple alleles,pleiotropy,and genotype-byenvironment interaction that underlies variation in the mean and plasticity of maize complex traits.It provides novel insights into the dynamic genetic architecture of agronomic traits in response to changing environments,paving a practical way toward precision agriculture.

A heavy metal transporter gene ZmHMA3a promises safe agricultural production on cadmium-polluted arable land

In China,19%of agricultural soils contain harmful heavy metal pollutants at levels exceeding environmentally recommended standards,whilst around 3 million hectares of arable land are too polluted to grow crops on(Zhao et al.,2015;Hu et al.,2016).Among the deleterious heavy metals,cadmium(Cd)is the most bioavailable toxic metallic pollutant and is rapidly transferable through the food chain(Wang et al.,2019).Concerning the current dilemma of the enhanced food demands of a rising population and decreasing availability of arable land,it is promising to cultivate field crops that produce enough safe foods for human consumption and simultaneously remove the pollutants from contaminated arable lands.