一种新型卷积神经网络植物叶片识别方法

为提高植物叶片识别的准确率及减少计算代价,在Pytorch框架下提出一种融合了深度卷积生成式对抗网络(DCGAN)和迁移学习(TL)的新型卷积神经网络叶片识别方法。首先,对植物叶片图像进行预处理,通过DCGAN对样本数据库扩充;其次,利用迁移学习将Inception v3模型应用于图像数据处理上,以提高植物叶片识别的准确率;最后,通过对比实验对该方法的有效性进行验证。结果表明:该方法可以获得96.57%的植物叶片识别精度,同时参数训练的迭代次数由4000次缩短到560次。     

Vibrio harveyi (VirB11) recombinant vaccine development against vibriosis in orange‐spotted grouper (Epinephelus coioides)

Despite significant improvements in aquaculture to compensate wild catch, disease organisms have thrived in limiting its national and global potential. Using antibiotics, in a bid to remedy the havoc, has given rise to complications, attracting attention to disease prevention by immune enhancement against diseases. Grouper production has been inhibited for the threats of bacterial infection, particularly of Vibrio origin. Considering the rise in vibriosis cases, improved vaccines are necessary; moreover, recombinant vaccines, the choice for trial in the present experiment have been effective and more specific in improving immunity. The current work deals with grouper immune system enhancement with a recombinant vaccine developed from VirB11 gene in Vibrio harveyi. VirB11 was cloned in V. harveyi for recombinant vaccine development against vibriosis in orange‐spotted grouper (Epinephelus coioides). As indicated by the results, recombinant VirB11 protein showed effectiveness in conferring protection against vibriosis with observable specific antibody response in enzyme‐linked immunosorbent assay (ELISA) analysis; a significant increase (p < 0.05) in antibody levels was observed after a week and after 8 weeks post‐vaccination. From the weeks post‐vaccination, log2 (antibody titres) in the sera of vaccinated groups reached a peak of 14.2 at week 5 in the vaccinated group in comparison with a peak of approximately 5 and 2 in adjuvant and PBS controls. As indicated by the challenge results, 90% relative survival was observed in vaccinated group and 13% relative survival in control group I (adjuvant control). The cumulative performance of protein concludes VirB11 commendable for recombinant vaccine development.     

温州龙湾国际机场入境旅客携带植物及其产品疫情 分析及应对措施

本文通过对2013—2018年温州空港口岸截获的入境旅客植物及其产品情况进行分析,发现温州空港口岸有害生物检出种类呈增长态势。6年共查获管制的植物和植物产品7495批次,截获有害生物110种,其中检疫性有害生物13种,占比11.82%。有害生物种类以昆虫居多,共55种,占比50%;热带水果检出有害生物最多,8种热带水果中检出12种检疫性有害生物。旅客携带物的有害生物检出具有时间季节效应,疫情来源地以东南亚中国台湾、中国香港、越南和泰国等国家和地区为主等特点。根据截获温州空港口岸入境旅客携带植物及其产品检出有害生物特点,因地制宜对入境旅客携带物检验检疫提出相关应对策略。     

京津冀地区植被NDVI动态变化及其与气候因子的关系

[目的] 探究气候变化对植被覆盖变化的驱动机制，可为揭示区域乃至全球植被覆盖动态变化及其与气候变化之间的响应机制提供依据。[方法] 以MODIS NDVI，SRTM DEM，降水和气温为数据源，运用Theil-Sen Median趋势分析法、Mann-Kendall显著性检验法、R/S分析法和Pearson相关分析法等数学分析方法，结合ANUSPLIN气象插值模型，研究2001—2019年京津冀地区植被NDVI时空演变特征及预测未来变化趋势，并探究植被NDVI与降水和气温最大相关关系及时滞效应。[结果] ①2001—2019年京津冀地区植被NDVI整体呈波动上升趋势，上升速率为0.002 2/a，且未来植被NDVI呈改善趋势的面积略小于呈退化趋势的面积；②降水和气温对京津冀地区植被生长以正向促进作用为主，且降水对植被生长的作用强度高于气温；③植被NDVI对降水变化的滞后期略长于气温，京津冀地区植被生长受前3月的降水和前1月的气温影响最大。[结论] 在林业生态工程实施背景下，2001—2019年京津冀地区植被覆盖整体呈改善态势，尤以西北部为著；植被NDVI与降水和气温相关关系呈现出明显的地域差异，且植被生长相对降水和气温变化存在一定的滞后效应。     

鸡粪的施用对薄皮甜瓜果实糖积累及糖代谢相关酶活性的影响

为了探讨鸡粪以及鸡粪与尿素配施对薄皮甜瓜果实糖积累及糖代谢相关酶活性的影响,本试验以薄皮甜瓜DX108为试验材料,以尿素为氮源的处理为对照(CK),研究了相同施氮量条件下,鸡粪与尿素配施(A)以及鸡粪(B)对甜瓜果实葡萄糖、果糖和蔗糖含量的影响,分析了蔗糖磷酸合成酶(SPS)、蔗糖合成酶(SS,蔗糖合成与分解方向)、酸性转化酶(AI)和中性转化酶(NI)的活性。结果表明,与CK相比,B、A明显促进了果实中果糖、蔗糖及葡萄糖积累,尤其是显著增加了成熟果实中这3种糖的含量。相关性分析表明,CK的甜瓜果实蔗糖积累与AI活性呈显著负相关,葡萄糖与SPS和SS(蔗糖合成酶)合成方向酶活性呈显著正相关;A和B果实中蔗糖、葡萄糖和果糖积累(除B中葡萄糖积累)与SPS、NI活性呈显著或极显著正相关,与SS分解方向酶活性呈极显著负相关,而A果实中葡萄糖积累与SPS和NI活性呈极显著正相关。综上所述,A和B提高了果实中SPS、NI活性,降低了SS分解方向酶活性,进而促进了糖的积累。本研究结果为有机肥替代化学氮肥在甜瓜生产上的应用提供了理论依据。     

Regulation of fibroblast growth factor 9 on the differentiation of goat intramuscular adipocytes

It has been found that fibroblast growth factor receptor (FGF-FGFR) signaling can regulate the expression of adipocyte differentiation genes. FGF9 is one of the members of FGFs that mainly binds receptors FGFR2 and FGFR3. FGF9 is highly expressed in the adipose tissue of humans and mice, but there are few reports on the role of FGF9 in goat intramuscular adipocyte differentiation. Therefore, this study explored the effect of FGF9 on adipocyte differentiation through cell culture, interference, and overexpression. The expression of receptors FGFR1–FGFR4 in adipocyte differentiation and their effects on differentiation were detected to screen receptor gene of FGF9. Finally, the interaction between FGF9 and the receptor was tested by cotransfection. Our results showed that FGF9 interacts with FGFR2 to inhibit goat intramuscular adipocyte differentiation by regulating peroxisome proliferator-activated receptor gamma (PPARγ) and preadipocyte factor 1 (Pref1), which is a data support for subsequent pathway research.     

科研院所制度建设与思考 ——以中国热带农业科学院椰子研究所为例

制度建设是科研院所提升科技创新能力、推进成果转化应用、开展科技服务的重要保障.文章重点介绍了中国热带农业科学院椰子研究所制度建设的经验和做法,并结合科研院所实际,从制度建设的方法、程序、执行等方面提出了加强科研院所制度建设的建议.     

间作香露兜提高槟榔根系生长和土壤酶活性

采用盆栽试验的方法,对槟榔单作、香露兜单作和槟榔间作香露兜3种栽培模式下根系生长发育和土壤酶活性进行比较研究。结果表明：槟榔间作香露兜促进了槟榔干物质累积,且分配到根系的干物质相对增多,地下部干物质质量显著增加,对香露兜的影响不显著;间作后显著增加槟榔叶片SPAD值,对香露兜无显著影响;间作模式下槟榔总根长、根系总表面积、根数目显著增多,分别比单作增加了78.64%、50.96%、81.22%,而且间作对槟榔根系生长发育的促进作用大于香露兜;槟榔间作香露兜后,土壤酸性磷酸酶、过氧化氢酶和过氧化物酶活性均显著高于槟榔单作,土壤脲酶与槟榔单作无显著差异,但显著低于香露兜单作;土壤过氧化物酶活性与根数目和根体积呈显著正相关。综上所述,槟榔与香露兜根系之间竞争较小,与槟榔单作相比,槟榔间作香露兜模式能够促进槟榔根系生长,提高土壤酶活性。