西瓜种子带菌部位及药剂处理试验研究

本文利用吸水纸检验法对从西瓜枯萎病发病较重地采集的种子进行了保湿培养研究,结果表明,供式种子携带多种病菌,其中枯萎病菌带菌率最高,其次是黑斑病菌、黑根霉菌;供试种子除表面带菌外,种壳和种仁内均可带菌,而且种壳带菌率明显高于种仁带菌率。药剂处理种子试验结果表明,80%越微多菌灵可湿性粉剂和50%扑海因可湿性粉剂100倍液浸种6小时分别对枯萎病菌和链格孢菌的消毒效果最好。     

几种杀菌剂对小麦纹枯病的防治效果

田间试验结果表明,12.5%烯唑醇可湿性粉剂有效成分110g/hm2、12.5%腈菌唑乳油110g/hm2、10%氯啶菌酯乳油45g/hm2、25%丙环唑乳油180g/hm2对小麦纹枯病有很好的防治效果,防效分别为79.5%、76.3%、65.8%和63.9%,显著优于常用药剂20%井冈霉素水溶性粉剂180g/hm2的防效52.9%,可在生产上大面积推广应用。     

竹缺爪螨生物学特性及其发生与环境的关系

研究结果表明,竹缺爪螨（ Ａｐｏｎｙｃｈｕｓｃｏｒｐｕｚａｅ Ｒｉｍａｎｄｏ） 营两性或孤雌生殖,孤雌生殖产雄卵;雌螨日产卵１ ～２ 粒,一生平均产卵９－８ 粒;林间自然性比为２－３５∶１ ;该螨以雌成螨和卵滞育,１１ 月中旬入蛰,３ 月上旬出蛰;在一定温度范围内,各螨态发育历期随温度升高而变短,从卵到成螨产卵有效积温为２８０－７６ 日度,发育起始温度为１３－３２ ℃。该螨还可取食苦绿竹（ Ｄｅｎｄｒｏｃａｌａｍ ｕｓｂａｓｉｈｉｒｓｕｔａ） 、长毛米筛竹（ Ｂａｍｂｕｓａ ｐａｃｈｉｎｅｎｓｉｓ） 、半耳箬竹（ Ｚｎｄｒｏｃａｌｍｕｓｌｏｎｇｉａｕｒｔｕｓ） ,并完成其生活史,在麻竹（ Ｄｅｎｄｒｏｃａｌａｍｏｐｓｉｓｌａｔｉｆｌｏｒｕｓ） 、毛金竹（ Ｐｈｙｌｌｏｓｔａｃｈｙｓｎｉｇｒａ） 上不能存活,在苦绿竹上完成１ 代需１８－４ ｄ;降雨的冲刷及浸水对幼、若、成螨存活影响较大,短期浸水对卵孵化影响不大,浸水１ ｄ 后卵孵化率降至３０－６５ ％ 。利用灰色关联度（Ｔｈｅ Ｇｒａｙ Ｓｅｑｕｅｎｃｅ） 方法分析湿度、气温、降雨量、天敌４ 个因子对该螨种群消长的影响,结果表明,４ 个因子对幼、若、成螨数量消长的关联序为湿度＞ 降雨量＞ 天敌     

10种常见野菜的抗菌初步筛选研究

[目的]为筛选具有杀菌能力的野菜植物。[方法]以金黄色葡萄球菌（Staphyloccocus aureus）、枯草芽孢杆菌（Bacillussubtilis）、大肠杆菌（Escherichia coli）为供试菌,对常见的10种野菜植物水提物进行琼胶平板法离体抑菌筛选试验。[结果]枸杞、二月兰、菌陈蒿对3种供试菌具有较强的抑菌活性。其中,枸杞对大肠杆菌的抑菌性最强,荠菜、丁香、地黄仅对某种细菌具有抑制性。[结论]枸杞、二月兰和菌陈蒿可以作为杀菌植物资源。     

Assessing grain crop water productivity of China using a hydro-model-coupled-statistics approach: Part I: Method development and validation

Identifying and quantifying the links between water resources and food production is crucial in addressing the intensified conflicts between water scarcity and food security. We proposed an integrated framework for quantifying relationships between food and water based on the concept of green water (GW), blue water (BW) and crop water productivity (CWP). An estimation method coupling hydrologic model and crop and water statistics was developed and validated to quantify basin-scale GW, BW and CWP in breadbasket basins of China. A basin-scale GW and BW assessment method was developed by using the Soil and Water Assessment Tool (SWAT). Monthly-step calibration and validation were performed at 15 discharge flow stations in seven first-order river basins of the country. The coefficient of determination (r²) and Nash-Sutcliffe Efficiency (NSE) in calibration stage ranged from 0.18 to 0.95, and −4.22 to 0.93, respectively; while in validation period, r² ranged from 0.02 to 0.97 and NSE ranged from −266.7 to 0.96. The simulated available soil water was validated against the observed soil moisture data, and the results showed that the model can reflect the yearly average values of soil water storage. Overall, the modeling performance for river basins with 4.94 million km² of drainage areas in total was acceptable. The simulated hydrologic components were then coupled with crop-and-water-statistics-based estimation method for assessing basin-scale CWP on four staple grain crops, i.e. rice, wheat, maize, and soybean. The results were validated by comparing with the similar investigations in China and around the globe. It was concluded that the overall performance of the estimation method was acceptable, and the method can be applied in assessing basin-scale GW, BW and CWP in China.     

鸭粪提取物对水稻纹枯病菌的影响及其有效成分分析

为探明稻鸭共养模式抑制水稻纹枯病发生的原因,以稻鸭共养模式的鸭粪提取物为研究对象,对其抑菌活性及有效成分进行了测定和分析,以期为水稻纹枯病生物防治提供新的途径。结果表明:鸭粪乙醇提取物对水稻纹枯病菌有抑制作用,24h内最高菌丝生长抑制率和EC50分别为88.64%、26.11mg·mL-1;鸭粪乙醇提取物经萃取分离得到石油醚和乙酸乙酯两种组分,其中石油醚组分抑菌效果较弱,乙酸乙酯组分抑菌能力较强,其对水稻纹枯病菌抑制率为89.70%,EC50为15.52mg·mL-1;对乙酸乙酯组分进行硅胶柱层析分离得到5种流份,其中第2流份有显著抑菌活性,在24h和48h内对水稻纹枯病菌的抑制率分别为89.58%和80.36%。GC-MS分析表明,鸭粪的抑菌物质主要为酚酸类和含硫醇有机物质,进一步纯化和鉴定有待研究。     

江苏省葡萄炭疽病菌群体对4种杀菌剂的敏感性

为明确江苏省葡萄炭疽病菌Colletotrichum gloeosporioides群体对苯醚甲环唑、吡唑醚菌酯、咯菌腈和戊唑醇4种杀菌剂的敏感性和抗性水平,本研究采用菌丝生长速率法测定了来自江苏省7个地区的68株葡萄炭疽病菌对上述4种药剂的敏感性,建立敏感基线,并分析菌株抗性水平和抗性频率。结果表明：苯醚甲环唑、吡唑醚菌酯、咯菌腈和戊唑醇对供试68株葡萄炭疽病菌的EC₅₀范围分别为0.03～1.20、0.05～3.48、0.14～1.20 mg/L和0.50～12.30 mg/L;对苯醚甲环唑、吡唑醚菌酯和咯菌腈的敏感基线分别为(0.53±0.032)(1.00±0.15) mg/L和(0.38±0.024) mg/L。68株菌株对戊唑醇的EC₅₀平均值为3.61 mg/L,因敏感性频率分布不符合建立敏感性基线要求,故未建立敏感性基线。供试菌株对苯醚甲环唑均表现为敏感,对吡唑醚菌酯和咯菌腈呈现一定的低抗水平,抗性频率分别为4.41%和3.03%;对戊唑醇呈低抗和中抗水平,抗性频率分别为16.18%和5.88%。该研究为防控江苏省葡萄炭疽病提...     

官司河流域7种林分枯落物及土壤层水文效应1）

为定量评估森林水源涵养能力,结合野外采样和浸水试验对官司河流域7种林分枯落物及土壤层水文效应进行比较。结果表明：林分枯落物蓄积量范围为4．49～13．19 t· hm－2,其中马尾松纯林最大,麻栎纯林最小;各林分枯落物最大持水深和有效拦蓄量均表现为未分解层大于半分解层,且纯竹林最大,分别为2．87 mm和9．77 t· hm－2。枯落物层持水量和吸水速率与浸水时间均显著。各林分0～30 cm土壤总孔隙度变化范围为37．1％～54．3％,竹林和松栎混交林的表层土壤有效持水量最大,分别为256．52、44．5 t· hm－2。纯竹林、松栎混交林持水效果较好,可作为水源涵养林得以推广。     

Is the use of formulae a reliable way to predict the accuracy of genomic selection?

We studied four formulae used to predict the accuracy of genomic selection prior to genotyping. The objectives of our study were to investigate the impact of the parameters of each formula on the values of accuracy calculated using these formulae, and to check whether the accuracies reported in the literature are in agreement with the formulae. First, we computed the marginal distribution of accuracy (by integration) for each parameter of all four formulae: heritability h², reference population size T, number of markers M and number of effective segments in the genome M_e. Then, we collected 145 accuracies and corresponding parameters reported in 13 publications on genomic selection (mainly in dairy cattle), and performed analysis of variance to test the differences between observed and predicted accuracy with effects of formulae and parameters. The variation of accuracy for different values of each parameter indicated that two parameters, T and M_e, had a significant impact and that considerable differences existed between the formulae (mean accuracies differed by up to 0.20 point). The results of our meta‐analysis showed a big formula effect on the accuracies predicted using each formula, and also a significant effect of the value obtained for M_e calculated from N_e (effective population size). Each formula can therefore be demonstrated to be optimal depending on the assumption used for M_e. In conclusion, no rules can be applied to predict the reliability of genomic selection using these formulae.     

不同杀菌剂对富贵竹修口和顶侧芽生长的初步研究

以12个月生富贵竹剥除叶片的茎干剪取做富贵竹塔的外层（10cm）和次外层（15cm）的枝条为材料,采用不同杀菌剂分别对其下发口和上切口进行处理,比较不同杀菌剂对其枝条上切口修口和顶侧芽生长的影响。试验结果表明,下切口1种和2种混合杀菌剂处理,对参试材料的上切口白色枝数、平滑枝数、顶侧芽长度,其差异均不显著;上切口3种杀菌处理,对参试材料的上切口白色枝数、平滑枝数和顶测芽长度差异均达极显著水平;15cm枝条各处理组合的上切口白色枝数差异达极显著水平。参试材料的上切口平滑枝数（X）与顶侧芽长度（Y）均呈极显著相关关系。