Determinants of groundnut rosette virus disease occurrence in Uganda

Groundnut rosette virus disease (GRVD) is the major constraint to groundnut (Arachis hypogaea) production in Uganda. It is principally transmitted by the groundnut aphid (Aphis craccivora Koch). The disease is known to cause total crop failure in cases where susceptible varieties are used. During any particular season, GRVD displays variations in incidence and severity in different agro-ecologies within the country, but the reasons for the varying disease patterns remain unclear. This study was aimed at establishing the factors influencing the occurrence of GRVD in Uganda. Trials were established for three seasons in four groundnut growing locations situated in different agro-ecologies in Uganda. Four groundnut genotypes were used as treatments in a randomized complete block design with four replications. Disease progress and aphid populations were assessed at 4, 8 and 12 weeks after planting. Data on environmental factors; particularly rainfall, temperature and wind speed were obtained from standard meteorological stations located at/near the study sites. Soil samples and yield data were also obtained in each season. The study revealed that disease incidence; severity and groundnut yields were significantly affected by season, location and genotype. The same applied to their three way interactions. Levels of disease infection were found to be majorly influenced by rainfall and wind speed. Disease incidence and severity were generally higher in conditions with less rainfall and low wind speeds. The Pearson's two tailed correlation between total rainfall and disease incidence for all trial sites was negative and highly significant (r = −0.280, P ≤ 0.01). The same was true for wind speed and disease incidence (r = −0.476, P ≤ 0.01). However, there was no conclusive trend between temperature and disease incidence with the Pearson's two tailed correlation showing significantly positive and negative trends depending on location.     

新式墙面绿化在广州和深圳的应用研究

新式墙面绿化对日益缩减的城市绿化环境至关重要,通过实地调查广州和深圳30个新式墙面绿化场所,分析其种植形式、植物种类、植物配置与景观效果,总结出深圳和广州新式墙面绿化的植物应用现状和景观效果,并讨论其发展前景。     

海南省儋州市两院地区茶树蜘蛛种类调查

[目的]为茶园生态防治做基础性调查。[方法]采用形态对比法,对海南省儋州热作两院地区茶园蜘蛛种类进行调查。[结果]经初步鉴定,明确有蜘蛛共42种,分别属于12科30属,其中5种鉴定到属,另有4种只鉴定到科,未列入其中。[结论]该次调查仅做种类鉴定,但鉴于蜘蛛在生态防治上的重要性,有必要做进一步的调查。     

我国橡子资源的开发利用

橡子营养丰富，而且具有多种功能特性，广泛应用在食品和其它工业中。对橡子仁、橡子皮质和橡子壳的成分、功能和应用等研究情况进行了综述，并介绍了橡子资源在食品及其它工业领域的应用进展，以及提出了橡子资源开发与研究过程中遇到的问题和解决方案。     

Temperature-dependent development of Ascotis selenaria (Lepidoptera: Geometridae) and its stage emergence models with field validation

Temperature-dependent development of Ascotis selenaria (Denis et Schiffermüller) was studied in the laboratory. Time to egg eclosion decreased with increasing temperature and ranged from 17.4 d at 16 °C to 5.0 d at 30 and 32 °C. Total development times of larvae decreased from 54.7 d at 16 °C to 17.3 d at 32 °C. The development time of pupae ranged from 29.7 days at 16 °C to 10.2 days at 30 and 32 °C. Eggs, larvae and pupae did not develop successfully to the next stage at 12 and 35 °C. The estimated lower temperature thresholds were 10.4, 9.3, and 9.8 °C for eggs, larvae, and pupae, respectively. Thermal constants of egg, larvae, and pupae were 88.5, 370.4, and 188.7 DD, respectively. Stage emergence models for eggs, larvae, and pupae of A. selenaria were constructed by using the development rate model (Lactin 2 function) and development distribution model (three-parameter Weibull function), which simulate the proportion of individuals shifted from one stage to the next. Pearson's correlation coefficients between actual observations in the field and model outputs were statistically significant with 0.99, 0.68 to 0.87 and 0.96 to 0.98 for egg, larval and pupal stage emergence model, respectively. The egg stage emergence model could be used to facilitate spraying time as it successfully predicted the first instar larval population. Predictability of the pupal stage emergence model was greatly improved when the physiological age of overwintering pupae was assumed to be in various state. The stage emergence models developed here should be useful to construct an A. selenaria population model.     

第三次全国农作物种质资源调查与收集行动湖南茶树专项总结报告

2015年10月至2018年12月,项目组参与第三次全国农作物种质资源调查与收集行动,对湖南省茶树种质资源进行普查、调查和征集、收集,共普查、调查和征集、收集茶树种质资源165份,涉及45个农业县(市、区),范围为东经109.176821°~114.005865°、北纬24.943720°~29.819774°、海拔31.33~1469.00m,并对湖南茶树种质资源的保护和合理开发利用提出了建议。     

蒙古族“茶境”探析

古人常用“骏马秋风蓟北,杏花春雨江南”概括南北两地风土人情,仿佛煮茗烹茶之事与漠北草原的蒙古族并无瓜葛。殊不知茶已随南北贸易的繁荣与发达而悄然北上,并逐渐形成了独特的饮茶境遇。本文从器、烹、礼、寓、忌等五个方面对蒙古族“茶境”进行系统探索与阐述,旨在为蒙古族饮茶文化的研究提供参考。     

供应链金融视角下木材加工产业的发展路径优化策略

木材加工企业的发展离不开金融机构的有效支持,当这种支持上升到一定高度时,整个木材加工产业也会处于金融服务机构的供应链管理范畴。供应链金融管理能力的强弱,将直接影响到木材加工企业的生产经营。介绍了供应链金融内容与特征,探讨了供应链金融视角下木材加工产业应规避的问题,在此基础上,提出了供应链金融视角下木材加工产业发展路径优化策略。     

茶园土壤-茶树-茶叶-茶汤中镉转移规律及安全性评价

为论证镉污染土壤种植茶树的安全性与可行性,通过盆钵茶园试验研究了湖南9个主栽茶树品种在不同镉含量土壤中对镉的吸收积累特性和茶汤中镉元素的浸出率。结果表明,在pH值4.1的土壤中,通过根系吸收的镉元素从根系到主干,再到侧枝枝干和茶树叶片的转运过程中,各器官的镉含量依次递减,茶树嫩芽(叶)中镉的富集系数仅0.13~0.24;茶树种植在土壤镉含量低于3.0 mg/kg的土壤中,茶叶没有出现镉超标现象;镉元素在茶汤中的平均浸出率为9.87%,利用膳食暴露风险评估模型对茶叶和茶汤中的镉含量进行风险评估,表明供试茶叶样品中的镉不会对人体健康产生威胁。     

基于称重式蒸渗仪的淮北平原冬小麦蒸散估算模型的本地化

为了解不同作物蒸散量估算方法在淮北地区的适用性,利用新马桥实验站称重式蒸渗仪测定了2016-2017年冬小麦全生育期的实际蒸散值,结合Hargreaves-Samani(H-S)、 FAO-56 PM、Turc、Makkind(Mak)、 Priestley-Taylor(P-T)、Mcloud(Mcl)和DeBruin-Keijman(D-K)7个模型,分析了冬小麦田的蒸散特征,将蒸散的估算值(ET_0)和实测值(ET_C)进行了对比。结果表明,相对于ET_C值,7个模型拟合得到的ET_0的RMSE值为0.99～2.29 mm·d~(-1),且H-S FAO-56 PMTurcMakP-TMclD-K; ET_C与ET_0的相关系数为0.74～0.97,其中FAO-56 PM的相关性最高,P-T、 Mak、 D-K、 H-S也表现出较好的相关性。综合来看,H-S法总体表现较好,更适合该地区。对6种主要气象要素与实测蒸散值进行主成分分析发现,温度是影响ET_C的主要因子,湿度、日照时数和平均风速(2 m)对淮北冬小麦田蒸散值的影响不大;H-S模型以温度数据为基础,利用线性订正法和湿度指数项订正法将H-S模型本地化后检验发现,其优化结果良好,RMSE降低(0.68 mm·d~(-1))。