小麦新型化杀剂SC2053诱导花粉败育的机制研究

SC2053是美国 Soegtal 公司研制,并与天津市作物所合作筛选出的一种新型化学杀雄剂。本文报道了 SC2053诱导花粉败育的细胞学结果:SC2053对花粉母细胞减数分裂过程无影响。其作用在于减数分裂四分体后、花粉粒形成时期,抑制花粉粒的发育进程,使花粉发育停留在单核或二核阶段。在开花期前,又诱导大量花粉粒内含物解体,形成空腔畸型花粉。KI-I 溶液检查,除大都化内含物已解体的花粉粒染色很浅外,内含物未解体的花粉粒因不含或含极少数淀粉,染色亦很浅,均表现为败育。     

典型草原普通栗钙土土壤湿度空间变异的初步研究

在一块面积为60m×60m 的样地上用重复距离倍增的方法布置了72个取样点,初步研究了草原地区普通栗钙土(暗栗钙土)湿度的空间变异及相关特性。结果表明,在天然植被覆盖下的暗栗钙土,浅层的土壤湿度大,其变异程度也较高,计算平均含水量的土层越厚,则相对变异程度越小。各层土含水量的统计特征都遵循正态分布。浅层相关距离较短,多层平均含水量的相关距离近于各层相关距离的平均值。     

Strategies for monitoring within-field soybean yield using Sentinel-2 Vis-NIR-SWIR spectral bands and machine learning regression methods

Soybean crop plays an important role in world food production and food security, and agricultural production should be increased accordingly to meet the global food demand. Satellite remote sensing data is considered a promising proxy for monitoring and predicting yield. This research aimed to evaluate strategies for monitoring within-field soybean yield using Sentinel-2 visible, near-infrared and shortwave infrared (Vis/NIR/SWIR) spectral bands and partial least squares regression (PLSR) and support vector regression (SVR) methods. Soybean yield maps (over 500 ha) were recorded by a combine harvester with a yield monitor in 15 fields (3 farms) in Paraná State, southern Brazil. Sentinel-2 images (spectral bands and 8 vegetation indices) across a cropping season were correlated to soybean yield. Information pooled across the cropping season presented better results compared to single images, with best performance of Vis/NIR/SWIR spectral bands under PLSR and SVR. At the grain filling stage, field-, farm- and global-based models were evaluated and presented similar trends compared to leaf-based hyperspectral reflectance collected at the Brazilian National Soybean Research Center. SVR outperformed PLSR, with a strong correlation between observed and predicted yield. For within-field soybean yield mapping, field-based SVR models (developed individually for each field) presented the highest accuracies. The results obtained demonstrate the possibility of developing within-field yield prediction models using Sentinel-2 Vis/NIR/SWIR bands through machine learning methods.

     

一种新型葡萄越冬埋藤机的设计

针对中国北方葡萄冬季越冬埋藤作业以人工作业为主,劳动强度大、效率低等问题,设计了一种新型葡萄埋藤机。结果表明,该机埋藤质量好、通用性好、不易堵塞且覆土后的葡萄无冻伤和风干现象;覆土厚度平均33.7 cm,宽度105.9 cm,抛土距离平均为51.1 cm,取土宽度平均为98.3 cm,挖沟距根部距离平均53.5 cm,可满足葡萄冬季埋藤的农艺要求。     

蓖麻eIF5A基因克隆与生物信息学分析

真核细胞翻译起始因子5A(eIF5A)是一种广泛存在真菌、动植物体内的蛋白质翻译起始因子,也是一种对调控生物生长发育、衰老及环境适应等产生重要作用的影响因子。本研究利用设计的蓖麻蛋白翻译起始因子5A基因的引物对蓖麻‘2129’基因组DNA进行PCR扩增并进行生物信息学分析。结果发现,该目的片段长为480bp,通过对该基因进行理化性质分析发现其分子量为39670.20Da,等电点(pi)为5.22,是一种疏水性不稳定蛋白,通过多序列比对和系统发育树分析发现,蓖麻eIF5A与同属大戟科的麻疯树亲缘关系最近,而与锦葵科的陆地棉亲缘关系最远。以上结果将为今后揭示蓖麻eIF5A蛋白功能提供重要的线索。     

Derivation of salt content in salinized soil from hyperspectral reflectance data: A case study at Minqin Oasis,Northwest China

Soil salinization is a serious ecological and environmental problem because it adversely affects sustainable development worldwide, especially in arid and semi-arid regions. It is crucial and urgent that advanced technologies are used to efficiently and accurately assess the status of salinization processes. Case studies to determine the relations between particular types of salinization and their spectral reflectances are essential because of the distinctive characteristics of the reflectance spectra of particular salts. During April 2015 we collected surface soil samples(0–10 cm depth) at 64 field sites in the downstream area of Minqin Oasis in Northwest China, an area that is undergoing serious salinization. We developed a linear model for determination of salt content in soil from hyperspectral data as follows. First, we undertook chemical analysis of the soil samples to determine their soluble salt contents. We then measured the reflectance spectra of the soil samples, which we post-processed using a continuum-removed reflectance algorithm to enhance the absorption features and better discriminate subtle differences in spectral features. We applied a normalized difference salinity index to the continuum-removed hyperspectral data to obtain all possible waveband pairs. Correlation of the indices obtained for all of the waveband pairs with the wavebands corresponding to measured soil salinities showed that two wavebands centred at wavelengths of 1358 and 2382 nm had the highest sensitivity to salinity. We then applied the linear regression modelling to the data from half of the soil samples to develop a soil salinity index for the relationships between wavebands and laboratory measured soluble salt content. We used the hyperspectral data from the remaining samples to validate the model. The salt content in soil from Minqin Oasis were well produced by the model. Our results indicate that wavelengths at 1358 and 2382 nm are the optimal wavebands for monitoring the concentrations of chlorine and sulphate compounds, the predominant salts at Minqin Oasis. Our modelling provides a reference for future case studies on the use of hyperspectral data for predictive quantitative estimation of salt content in soils in arid regions. Further research is warranted on the application of this method to remotely sensed hyperspectral data to investigate its potential use for large-scale mapping of the extent and severity of soil salinity.     

矮杆大穗高产小麦育种亲本SW3243重要农艺性状特性及育种应用效果

摘要 小麦冬春杂交后代SW3243是四川的重要亲本及推广品种,组合为1426/4/IR68-77/YAA//ALD‘S’/3/YAZ//ST2022/983。SW3243高抗条中29、30,对抗性基因不具有抑制作用;具有矮杆、多花、大穗、高产、迟播早熟等显著特点。利用SW3243的优良农艺特性育成了一批高产新品系,其中有42个衍生系参加了国家和四川省区试,育成小麦新品种7个,审定10次（四川省审定7次,国家审定3次）;SW3243及其衍生品种已累计推广433万公顷以上,对四川的小麦育种及生产做出了重要贡献。本文旨在对SW3243 的选育及重要农艺性状和育种应用作一总结,为进一步的小麦种质资源创新和高产育种提供信息。     

几种防冻剂在茶树上的应用研究

摘要：研究了通微、柳州、标典三种防冻剂对茶树抗寒能力和品质的影响,结果表明：①选用合适的防冻剂,能增强茶树抗寒能力;②防冻剂对茶树生长势、茶叶品质有一定的促进作用;③因地制宜,正确施用防冻剂;④综合防冻剂对茶树的抗冻效果和对茶叶产量、品质的影响,三种防冻剂当中以标典最好。     

梨4个SFBB~(-γ)基因的分离及遗传多态性分析

By using PCR-based molecular method,four new pear SFBB-γ genes were isolated from 8 pear cultivars known as S-genotypes.Length of PCR products from eight pear cultivars was around 1 200 bp.Sequencing the specific PCR fragments revealed four new SFBB-γ genes that were respectively named as SFBB 16-γ (EU422956),SFBB 17-γ (EU422957),SFBB 28-γ (EU422960)and SFBB 35-γ (EU422958).As for different SFBB-γ genes,variation in amino acid was higher in F-box region and variable region 1,and lower in variable region 2 t...     

茶树扦插苗圃地夏季覆地膜消毒研究

为免去在茶树扦插地苗床上铺黄心土,达到直接在原土上进行茶树短穗扦插育苗的目的,选择夏季某一时段对茶树扦插苗圃地进行覆地膜处理,利用晴天时地膜下产生的湿热高温,杀灭苗床表层土壤中的有害微生物。结果表明：茶树苗圃地夏季覆地膜处理,晴天时膜下地表温度最高可以达到65.0℃,膜下5 cm深处土层温度可达54.2℃;通过较高温度的持续性和间歇性循环作用,5 cm深处土层温度(50±1)℃持续2 h达7~10天,可杀灭表层扦插土壤中的真菌类微生物95%以上,并有效控制其他有害微生物的生长;覆地膜处理的苗圃,扦插5个月后,愈合率达82.9%,成苗率在55.1%以上,与铺黄心土扦插成苗率相当,且扦插直接成本每公顷可节约15000元以上。夏季覆地膜可广泛应用于茶树短穗扦插土壤的消毒处理。