Plants mount induced resistance and adult-plant resistance against different pathogens throughout the whole growth period. Rice production faces threats from multiple major diseases, including rice blast, sheath blight, and bacterial leaf blight. Here, we report that the miR172a-SNB-MYB30 module regulates both induced and adult-plant resistance to these three major diseases via lignification in rice. Mechanistically, pathogen infections induce the expression of miR172a, which downregulates the transcription factor SNB to release its suppression of MYB30, leading to an increase in lignin biosynthesis and disease resistance throughout the whole growth period. Moreover, expression levels of miR172a and MYB30 gradually increase and are consistently correlated with lignin contents and disease resistance during rice development, reaching a peak at full maturity, whereas SNB RNA levels are negatively correlated with lignin contents and disease resistance, indicating the involvement of the miR172a-SNB-MYB30 module in adult-plant resistance. The functional domain of SNB protein and its binding sites in the MYB30 promoter are highly conserved among more than 4000 rice accessions, while abnormal expression of miR172a, SNB, or MYB30 compromises yield traits, suggesting artificial selection of the miR172a-SNB-MYB30 module during rice domestication. Taken together, these results reveal a novel role for a conserved miRNA-regulated module that contributes significantly to induced and adult-plant resistance against multiple pathogens by increasing lignin accumulation, deepening our understanding of broad-spectrum resistance and adultplant resistance.

Flower opening and stigma exertion are two critical traits for cross-pollination during seed production of hybrid rice (Oryza sativa L.). In this study, we demonstrate that the miR167d-ARFs module regulates stigma size and flower opening that is associated with the elongation of stamen filaments and the cell arrangement of lodicules. The overexpression of miR167d (OX167d) resulted in failed elongation of stamen filaments, increased stigma size, and morphological alteration of lodicule, resulting in cleistogamy. Blocking miR167d by target mimicry also led to a morphological alteration of the individual floral organs, including a reduction in stigma size and alteration of lodicule cell morphology, but did not show the cleistogamous phenotype. In addition, the four target genes of miR167d, namely ARF6, ARF12, ARF17, and ARF25, have overlapping functions in flower opening and stigma size. The loss-of-function of a single ARF gene did not influence the flower opening and stigma size, but arf12 single mutant showed a reduced plant height and aborted apical spikelets. However, mutation in ARF12 together with mutation in either ARF6, ARF17, or ARF25 led to the same defective phenotypes that were observed in OX167d, including the failed elongation of stamen filaments, increased stigma size, and morphological alteration of lodicule. These findings indicate that the appropriate expression of miR167d is crucial and the miR167d-ARFs module plays important roles in the regulation of flower opening and stigma size in rice.

Magnaporthe oryzae is the causative agent of rice blast, a devastating disease in rice worldwide. Based on the gene-for-gene paradigm, resistance (R) proteins can recognize their cognate avirulence (AVR) effectors to activate effector-triggered immunity. AVR genes have been demonstrated to evolve rapidly, leading to breakdown of the cognate resistance genes. Therefore, understanding the variation of AVR genes is essential to the deployment of resistant cultivars harboring the cognate R genes. In this study, we analyzed the nucleotide sequence polymorphisms of eight known AVR genes, namely, AVR-Pita1, AVR-Pii, AVR-Pia, AVR-Pik, AVR-Pizt, AVR-Pi9, AVR-Pib, and AVR-Pi54 in a total of 383 isolates from 13 prefectures in the Sichuan Basin. We detected the presence of AVR-Pik, AVR-Pi54, AVR-Pizt, AVR-Pi9, and AVR-Pib in the isolates of all the prefectures, but not AVR-Pita1, AVR-Pii, and AVR-Pia in at least seven prefectures, indicating loss of the three AVRs. We also detected insertions of Pot3, Mg-SINE, and indels in AVR-Pib, solo-LTR of Inago2 in AVR-Pizt, and gene duplications in AVR-Pik. Consistently, the isolates that did not harboring AVR-Pia were virulent to IRBLa-A, the monogenic line containing Pia, and the isolates with variants of AVR-Pib and AVR-Pizt were virulent to IRBLb-B and IRBLzt-t, the monogenic lines harboring Pib and Piz-t, respectively, indicating breakdown of resistance by the loss and variations of the avirulence genes. Therefore, the use of blast resistance genes should be alarmed by the loss and nature variations of avirulence genes in the blast fungal population in the Sichuan Basin.

Ustilaginoidea virens is a biotrophic fungal pathogen specifically colonizing rice floral organ and causes false smut disease of rice. This disease has emerged as a serious problem that hinders the application of high-yield rice cultivars, by reducing grain yield and quality as well as introducing mycotoxins. However, the pathogenic mechanisms of U. virens are still enigmatic. Here we demonstrate that U. virens employs a secreted protein UvCBP1 to manipulate plant immunity. In planta expression of UvCBP1 led to compromised chitin-induced defense responses in Arabidopsis and rice, including burst of reactive oxygen species (ROS), callose deposition, and expression of defense-related genes. In vitro -purified UvCBP1 protein competes with rice chitin receptor OsCEBiP to bind to free chitin, thus impairing chitin-triggered rice immunity. Moreover, UvCBP1 could significantly promote infection of U. virens in rice flowers. Our results uncover a mechanism of a floral fungus suppressing plant immunity and pinpoint a universal role of chitin-battlefield during plant–fungi interactions.

ABSTRACTCrop floral diseases are economically important as they reduce grain yield and quality and even introduce food toxins. Rice false smut has emerged as a serious floral disease producing mycotoxins. However, very little is known on the interaction mechanisms between rice flower and the causal fungus Ustilaginoidea virens. Here we show that a conserved anti-fungal immunity in rice flower is disarmed by U. virens via a secreted protein UvChi1. UvChi1 functioned as an essential virulence factor and directly interacted with the chitin receptor CEBiP and co-receptor CERK1 in rice to disrupt their oligomerizations and subsequent immune responses. Moreover, intraspecific-conserved UvChi1 could target OsCEBiP/OsCERK1 receptor complex in at least 98.5% of 5232 surveyed rice accessions. These results demonstrate that U. virens utilizes a crucial virulence factor to subvert chitin-triggered flower immunity in most rice varieties, providing new insights into the susceptibility of rice to false smut disease.One Sentence SummaryThe fungal pathogen Ustilaginoidea virens disarms chitin-triggered immunity in rice flower via a secreted chitinase.

microRNAs act as fine-tuners in the regulation of plant growth and resistance against biotic and abiotic stress. Here we demonstrate that rice miR1432 fine-tunes yield and blast disease resistance via different modules. Overexpression of miR1432 leads to compromised resistance and decreased yield, whereas blocking miR1432 using a target mimic of miR1432 results in enhanced resistance and yield. miR1432 suppresses the expression of LOC_Os03g59790, which encodes an EF-hand family protein 1 (OsEFH1). Overexpression of OsEFH1 leads to enhanced rice resistance but decreased grain yield. Further study revealed that miR1432 and OsEFH1 are differentially responsive to chitin, a fungus-derived pathogen/microbe-associated molecular pattern (PAMP/MAMP). Consistently, blocking miR1432 or overexpression of OsEFH1 improves chitin-triggered immunity responses. In contrast, overexpression of ACOT, another target gene regulating rice yield traits, has no significant effects on rice blast disease resistance. Altogether, these results indicate that miR1432 balances yield and resistance via different target genes, and blocking miR1432 can simultaneously improve yield and resistance.

为提高苹果生产中肥料利用效率以及解决大量施肥造成树体旺长、不易成花和果品品质下降的问题,本研究利用自制的生物活性素复合制剂,于2017-2019年在陕西省延安市选择正常管理下的4个不同树龄的红富士果园,采用常规施肥(对照)和增施生物活性素处理,从土壤理化性状、树体生长发育和果实品质等方面,去探究生物活性素对果园氮素利用及红富士苹果生长发育的影响.结果 表明:1)经生物活性素处理后,土壤全氮含量提高4.69％～51.35％,其中幼龄树果园中提高效果更为明显;2)处理后幼龄树的花芽数量连年增加,平均增加58.42％,成花树的比例平均提高22％;3)4个参试果园中果实产量均有提高,果实香气普遍提高;4)肥料偏生产力在3个果园中平均提高11,32％,总体呈增加趋势.施用生物活性素,对幼龄树可促进早花早果,对成龄树有一定增产提质的作用.综合来看,生物活性素的施用是黄土高原地区红富士苹果高效利用肥料及高产优质生产的有效措施.

目的 研究稳定同位素技术鉴别天麻真伪的可行性.方法 利用稳定同位素质谱仪测定天麻及其伪品碳、氮同位素比率,比较不同样品中稳定性碳、氮同位素含量的差异,对结果进行方差分析和聚类分析.结果 天麻及其伪品马铃薯、洋姜、紫茉莉、大丽菊的δ13C平均值分别为-24.2、-26.3、-30.4、-29.3、-26.2,方差分析结果为天麻δ13C值显著性高于马铃薯、洋姜、紫茉莉、大丽菊(P ＜0.000 1);聚类分析显示天麻样品属于一类,伪品属于其他类,证明δ13C值可以将天麻与伪品完全分开.天麻、马铃薯、洋姜、紫茉莉、大丽菊的δ15N平均值分别为-1.28、-0.53、-0.86、2.76、-0.73,方差分析结果为天麻δ15N值显著性低于马铃薯、紫茉莉、大丽菊(P＜0.000 1),而天麻与洋姜无显著性差异;聚类分析表明天麻样品与部分伪品聚在一起,没有单独归类,δ15N值不能将天麻与伪品完全分开.结论 利用稳定碳同位素δ13C值可明显将天麻与其他伪品分开;稳定氮同位素δ15N值可将天麻与部分伪品区分开,有一定的鉴别潜力,可作为一种参考.

[目的]探究化肥减施、化肥减施配合生物活性素施用对京津苹果园土壤及果树生长发育的效应.[方法]以京津地区4个不同树龄的正常管理‘富士’果园为试验点,试验设置3个处理:化肥减施30％、化肥减施30％配施生物活性素、对照.[结果]处理后,发现化肥减施30％有降低土壤pH的作用,对土壤养分、树体生长、单株产量和果实品质无显著影响;化肥减施30％配合施用生物活性素显著提高了花芽数量,增加了两个试验点(B J-2、T J-1)的花序数量.化肥减施以及生物活性素的施用将是一个长效过程,还需进一步试验加以验证.[结论]京津苹果园可减施化肥30％,在本地区减施化肥并施用生物活性素,可在一定程度促进树体生殖生长,降低土壤pH,不影响果实成熟和品质.

MicroRNAs (miRNAs) play essential roles in rice immunity againstMagnaporthe oryzae, the causative agent of rice blast disease. Here we demonstrate that Osa-miR162a fine-tunes rice immunity againstM. oryzaeand yield traits. Overexpression of Osa-miR162a enhances rice resistance toM. oryzaeaccompanying enhanced induction of defense-related genes and accumulation of hydrogen peroxide (H2O2). In contrast, blocking Osa-miR162 by overexpressing a target mimic of Osa-miR162a enhances susceptibility to blast fungus associating with compromised induction of defense-related gene expression and H(2)O(2)accumulation. Moreover, the transgenic lines overexpressing Osa-miR162a display decreased seed setting rate resulting in slight reduced yield per plant, whereas the transgenic lines blocking Osa-miR162 show an increased number of grains per panicle, resulting in increased yield per plant. Altered accumulation of Osa-miR162 had a limited impact on the expression of riceDicer-like 1(OsDCL1) in these transgenic lines showing normal gross morphology, and silencing ofOsDCL1led to enhanced resistance to blast fungus similar to that caused by overexpression of Osa-miR162a, suggesting the involvement ofOsDCL1in Osa-miR162a-regulated resistance. Together, our results indicate that Osa-miR162a is involved in rice immunity againstM. oryzaeand fine-tunes resistance and yield.

目的 研究稳定同位素技术用于鉴别酸枣仁的可行性.方法 以酸枣仁、理枣仁和枳椇子为试材,采用稳定同位素技术,测定酸枣仁、理枣仁和枳椇子的碳、氮同位素比率,对结果进行方差分析和聚类分析.结果 酸枣仁、理枣仁和枳椇子中稳定同位素δ13C平均值分别为-26.60、-27.50、-27.84,方差结果表明酸枣仁碳同位素比率平均值显著高于理枣仁和枳椇子(P ＜0.0028);聚类分析结果表明,利用碳同位素δ13C值聚类可以完全的将酸枣仁与理枣仁和枳椇子进行区分.酸枣仁、理枣仁和枳椇子中稳定同位素δ15N平均值分别为-1.38、2.31、1.98,方差结果表明为酸枣仁氮同位素比率平均值显著低于理枣仁和枳椇子(P＜0.0071);聚类分析结果表明,利用氮同位素δ15N值聚类可以区分出部分酸枣仁.理枣仁与枳椇子的碳同位素比率值、氮同位素比率值相近,碳方差分析、氮方差分析无显著性差异,碳聚类分析和氮聚类分析结果均为同一类.结论 稳定同位素技术可望为酸枣仁的真伪鉴别提供新的方法.

针对区域青稞产量低、施肥技术落后及手段单一等问题,通过田间裂区试验,探明不同施肥处理对青稞生长发育及产量的影响,明确不同青稞缓释肥料的施用效果及其在青稞种植中的应用价值.结果表明:在不同施肥水平下,条施(A1)各处理下A1B5居第1位,折合产量4165.5 kg/hm2,较对照增产23.2％;处理A1B3居第2位,折合产量4123.5 kg/hm2,较对照增产22.0％.撒施(A2)各处理下A2B4居第1位,折合产量3717.0 kg/hm2,较对照增产24.2％;处理A2B3居第2位,折合产量3211.5 kg/hm2,较对照增产7.3％.条施各处理下的小区产量高于撒施各处理,且施用缓释肥料B、缓释肥料C产量较高,施用缓释肥料A产量较稳定.故建议在甘南州青稞种植区域,施肥方式逐步改撒施为条施,并建立甘南地区青稞种植高效施肥技术.

Bridge grafting is widely applied in trunk-wounded apple trees. In this study, we carried out semigirdling and ring girdling on the trunk of 'Nagafu 2'/Malus baccata (L.) Borkh apple trees to simulate trunk injury. We then bridge grafted a M9 self-rooted rootstock on the injured trunks to study the effects of bridge grafting on flowering, fruitset, tree vigor, and fruit characteristics in 'Nagafu 2' apple. The results showed that both semigirdling and ring girdling due to the large wounded area caused significant decrease in flowering, fruit-set, and tree vigor (estimated by measuring leaf area, leaf gas exchange, tree height, and shoot growth); in addition, ring girdling increased flesh and peel firmness. However, bridge grafting of M9 self-rooted rootstock on semigirdling and girdling apple trees resulted in partial recovery of tree vigor (leaf area and photosynthesis) and maintaining the reduction of vegetative growth, thereby increasing flowering, fruit-set, yield, fruit weight, and peel firmness.

The instrument and equipment on field experiment station of agricultural science research institutes are important basis to carry out data monitoring, laboratory analysis and innovation research. Strengthening instrument management, rationally using equipment resources, and improving the efficiency of the instrument are the keys to give full play to the role of science and technology support for field experiment station. From a management point of view, instruments and equipments of field experiment station were classified, and problems about instrument usage and management were analyzed in the paper. Some suggestions were pointed out which included purchase of equipment, standard operation, performance appraisal, etc. The purpose is to provide reference on equipment management for the relevant field experiment stations of agricultural science research institutes.

甘南藏族自治州是以青稞为主要农作物的高原地区,青稞是当地民众的主要食粮,青稞单产及总产影响着区域内粮食安全和社会稳定.受气候环境、地理位置、藏汉双语等影响,甘南地区科技发展较为缓慢,群众科学意识较差,施肥技术水平较低,传统施肥方式仍占主导地位.为此,明晰现代农业中的高效施肥技术要点,摸清区域内青稞施肥技术应用现状,找出当前施肥技术中存在的问题,探讨高效施肥技术在青稞种植中的发展前景及推广措施,对甘南藏区青稞高产高效种植和农业发展方式转变具有重要意义.

This article,based on the current development status of technology platform,analyzes the technology supporting role of agricultural technology platforms in the development of modern agriculture.Combining with the technology innovation project of Chinese Academy of Agricultural Science,taking Institute of Agricultural Resources and Regional Planning as an example,the paper discusses the construction progress of technology platforms in this institute in recent years,proposes some problems on platform construction and management,reflects the direction of innovation and development of technology platforms,and then provides reference for the construction and development of technology platforms related research institu-tes.

In the present article, a 2-year maize field experiment for the whole growth period was conducted. Hyperspectral data and chlorophyll contents (SPAD) of maize leaves were measured respectively using portable spectrometer and SPAD-502 chlorophyll meter. Various spectral parameters were selected to build construct prediction models for maize leaf SPAD in annual growth periods based on correlation analysis of the two factors, and detailed validation and evaluation were made. The results showed that there was little difference between the mean curves of spectral reflectance or its first derivative in the two years; the sensitive areas were basically the same about the correlation coefficient curves of leaf SPAD and spectral reflectance or its first derivative; prediction models built with spectral parameters based on first derivative were unstable; prediction models built with LCI, DSI(R(550around), R(680around)) and DSI(R(680around), R(710around)) were all in good conditions, and maize leaf SPAD could be effectively predicted.

Pot experiments were conducted to discuss the effects of phosphate and potassium fertilizer placement on growth of summer maize seedling and improve utilization efficiency of P K fertilizer.The fertilization placements included the seed side 5 cm,seed side 10 cm,seed below 5 cm,and seed below 10 cm.The result showed there had a significant effect of P and K fertilizer placement on dry matter accumulation,nutrient uptake,and root growth of summer maize.To the experiment soil,the distance between P fertilizer and seed significantly affect the summer maize seedling growth.The distance of the phosphate fertilizer and seeds was closer,the longer the root length,the greater the amount of dry matter accumulation and the more nutrient uptake.The application orientation of phosphorus fertilizer,seed side and seed below,had not significant influence on maize growth.K fertilizer placement had not a significant effect on dry matter accumulation and root length of maize seedling,but had a slight impact on plant potassium content and root dry weight.The treatment which K fertilizer was closer to seed not only failed to promote the trend of K uptake but also reduce K uptake.The results of this experiment provide some guidance to nutrient management of P K on summer maize seeding stage,but the effect of P K fertilizer placement on the whole growth period of summer maize needs further study.

Normalized difference vegetation index(NDVI)is one of the most widely used spectrum parameters in crop monitoring,which has important practical guiding significance in crop production and management. In this paper,the application of NDVI in crop yield,biomass,harvest index and leaf area index,nutritional status,crop adjustment was discussed,the existing problems and deficiencies in current research were also summarized,and the research focus of NDVI in crop monitoring in future were put forward.

Imported equipment is the important foundation of scientific research institutes to carry out the work of scientific and technological innovation. Standardizing the duty-free application and equipment management has a significant role in promoting the rational fund use and equipment run efficiently. Taking the institute of agricultural resources and agricultural regionalization of Chinese Academy of Agricultural Sciences as an example,this paper in- troduced the current situation of imported equipment and the process of duty-free application,analyzed the focus of follow-up management work on imported equipment,and summarize some management experiences for providing reference for the relevant units.