两种光照下低海拔引种云锦杜鹃的光合作用日变化

以移栽的野生云锦杜鹃Rhododendron fortunei为材料,使用LI-6400便携式光合作用仪,分析10%光照和全光照下低海拔区域引种云锦杜鹃的光合日变化,结果显示10%光照下生长的云锦杜鹃蒸腾速率低于全光照下生长的云锦杜鹃,而水分利用效率高于全光照下云锦杜鹃的60.17%。两种光照下的云锦杜鹃净光合速率和蒸腾速率日变化呈现"单峰"型。全光照下净光合速率下降是非气孔限制引起的,而10%光照下则为气孔限制引起。研究说明种植在低海拔环境的云锦杜鹃喜光的特性并不因为温度高而改变,但夏季遮荫措施还是有必要的。     

松阳县古松树的松材线虫病现状调查与分析

古松树是历史的见证,是文化的承载,其保护工作具有重要意义,但因松材线虫的传播侵染,其生存状况不容乐观。本研究以松阳古松树为对象,基于分子检测技术,对其松材线虫病现状进行了调查与分析。结果表明,有12个乡镇近60%的古松树均已感病,疫情较为严重,需及时开展抗病保护工作。     

黄酒米浆水制备农用酵素营养液发酵过程中营养成分的变化

黄酒米浆水是黄酒酿造浸米工序中的副产物,属于高浓度有机废水,用之是宝,弃之严重污染环境。采用米浆水代替清水作为配料水,以叶菜类废弃物包括萝卜叶、白菜叶和莴笋叶为植物原料,混合红砂糖,自然发酵制备农用酵素营养液,研究其发酵过程中主要营养组分的变化规律。结果表明,利用黄酒米浆水制备的农用酵素营养液各营养组分在发酵过程中显著高于用清水制备的对照组（P<0.05）。不同植物材料制备的米浆水农用酵素营养液各营养组分变化趋势类似,总糖含量呈下降趋势,钾离子含量呈先升高后降低再升高变化,总氮、总磷、总酸和游离氨基酸含量整体均呈上升趋势;以萝卜叶农用酵素营养液为例,发酵90 d时,总糖含量下降76.68 %,总氮、总磷、钾离子、总酸和游离氨基酸总量分别上升40.56 %、53.58 %、22.83 %、33.08 %和183.4 %;17种游离氨基酸中丙氨酸含量最高,为3 677.4 mg·L^-1,提高638.6%。不同植物材料制备的农用酵素营养液均含有较丰富的养分,但养分含量差异明显（P<0.05）;其中萝卜叶农用酵素营养液发酵各时段总氮、总磷、总糖和总酸含量的平均值较高,分别为4.67 mg·mL^-1、628.20 mg·L^-1、5.22 %和13.30 g·L^-1;萝卜叶农用酵素营养液发酵90 d时游离氨基酸总量最高,为14 157.3 mg·L^-1;莴笋叶农用酵素营养液发酵各时段钾离子含量平均值较高,达到95.22 mmol·L^-1。     

嘧啶联吡唑甲酰胺类化合物的合成及除草活性

设计合成了一系列结构新颖的嘧啶联吡唑甲酰胺类化合物5a~5o,其结构均经过1H NM R和MS分析确证。初步生物活性测试结果表明:在有效成分150 g/hm2剂量下苗后茎叶喷雾处理时,化合物(R)-N-[1-(4-氯苯基)乙基]-3-二氟甲基-1-(4,6-二甲氧基嘧啶-2-基)-1H-吡唑-4-甲酰胺(5c)、N-[1-(4-氯苯基)乙基]-1-(4,6-二甲氧基嘧啶-2-基)-N-甲基-3-三氟甲基-1H-吡唑-4-甲酰胺(5i)和N-[1-(4-氯苯基)乙基]-1-(4,6-二甲氧基嘧啶-2-基)-3-三氟甲基-1H-吡唑-4-甲酰胺(5k)对繁缕Stellaria media的抑制率高达90%以上;而同样剂量下苗前土壤喷雾处理时,化合物N-[1-(4-氯苯基)乙基]-3-二氟甲基-1-(4,6-二甲氧基嘧啶-2-基)-1H-吡唑-4-甲酰胺(5b)和5c对繁缕的抑制率达100%。该类结构化合物有望作为除草先导化合物进行开发。     

新型喹啉类化合物ZJ5337的生物活性

ZJ5337(碳酸苄酯-2,3,8-三甲基-6-七氟异丙基-4-喹啉酯)是浙江省化工研究院有限公司创制的一种新型喹啉类杀菌剂。测定了ZJ5337在离体条件下对稻瘟病菌的抑菌效果以及在温室及田间对水稻稻瘟病和黄瓜白粉病的防治效果。在离体条件下,10~20 mg/L的ZJ5337对稻瘟病菌附着孢的形成有显著抑制作用。温室盆栽试验结果表明:在50~100 mg/L剂量下,ZJ5337对水稻稻瘟病和黄瓜白粉病的防效均在80%以上,持效期为15 d左右;其在黄瓜植株根部和叶片之间以及叶片与叶片之间内吸输导性差;叶面喷雾1~3 h内降雨能明显降低药剂防效,但4 h后降雨对其防效无显著影响。田间试验结果表明,采用2.5%的ZJ5337乳油在有效成分质量浓度为300~500 mg/L下,对水稻稻瘟病的防效为66%~91%,且对水稻安全。     

Fenton试剂降解除草剂溴嘧草醚的反应动力学研究

探讨了Fenton试剂对超高效除草剂溴嘧草醚(ZJ0777)的降解反应。考察了溴嘧草醚、过氧化氢、硫酸亚铁的初始浓度和反应温度等因素对溴嘧草醚降解反应的影响,建立了Fenton试剂降解溴嘧草醚的动力学方程。结果表明:在溴嘧草醚初始浓度分别为0.12和0.24 mmol/L时,达到其降解率90%以上所需的时间分别为32和48 h,而在溴嘧草醚为0.48 mmol/L时,反应84 h只有87%的溴嘧草醚降解;过氧化氢初始浓度在150~300 mmol/L范围内,浓度增加有利于降解反应进行;溴嘧草醚降解反应随亚铁离子浓度的增加而加快(5~20 mmol/L),但过高的亚铁离子浓度对降解反应无效。温度在25~45℃范围内,反应的表观活化能Ea为75.34 kJ/mol。溴嘧草醚的氧化降解符合假一级反应动力学模型。     

Control of postharvest grey mould (Botrytis cinerea Per.: Fr.) on strawberries by glucosinolate-derived allyl-isothiocyanate treatments

The vapours of allyl-isothiocyanate (AITC) were evaluated in in vitro and in vivo trials against Botrytis cinerea, a severe pathogen of strawberries. In in vitro trials AITC activity was assayed on conidial germination and mycelial growth of the fungus. The mycelium appeared less sensitive to AITC than conidia (EC₅₀ values of 1.35 mg L⁻¹ and 0.62 mg L⁻¹, respectively). In addition, AITC had a fungistatic effect against the pathogen, since the values of EC₅₀, for both parameters, increased by around 30% after AITC removal. In in vivo trials, ‘Tecla’ and ‘Monterey’ strawberries (spring-bearing and day-neutral cultivars, respectively) obtained from organic production and naturally infected by B. Cinerea, were exposed for 4 h in an atmosphere enriched by pure AITC or derived from defatted seed meals of Brassica carinata (0.1 mg L⁻¹, in a 0.1 m³ treatment cabinet). After 2 days at 0 °C and another 3–4 days at 20 °C, the fruit were evaluated for grey mould infections. The AITC treatment reduced the decay caused by the pathogen by over 47.4% up to 91.5%, significantly different from the untreated fruit. No significant differences were found between synthetic and glucosinolate-derived AITC. Residue analysis performed on fruit at the end of storage (7 d after treatment) showed values lower than 1 mg kg⁻¹. Total phenolic content and antioxidant capacity estimated in treated and untreated strawberries showed no significant difference between control and AITC treated fruit. Our results show it is possible to reduce the incidence of postharvest grey mould on strawberries with a treatment of AITC (0.1 mg L⁻¹) for 4 h, opening a potential application of biofumigation in the postharvest control of B. cinerea in strawberry.     

菁松皓月的种性维持及系统改良

本文通过对浙江省蚕种公司和中国农业科学院蚕业研究所提供的菁松、皓月品种的原原种和杂交种27年的历年饲育成绩和经济性状分析,认为菁松、皓月的主要经济性状没有改变,仍保持推广初期的饲育成绩水平,且某些经济眭状有所提高;同时阐述了菁松、皓月品种的种性维持及系统改良的方法和经验。     

Thermo characteristics of steam-exploded bamboo (Phyllostachys pubescens) lignin

Bamboo (Phyllostachys pubescens) internode was subjected to steam explosion treatment to produce an excellent fiber for binderless boards. Lignin was isolated from extract-free bamboo meal with Björkman’s procedure and steam-exploded pulp. The self binding-mechanism was discussed by scanning electron microscopy (SEM), thermo-gravimetry (TG), differential scanning calorimetry (DSC) and analytical ozonation. It is well-known that steam explosion treatment liberates lignin from the cell wall to the fiber surface, which is the most important component relevant to binderless board production. Results of TG and DSC analyses showed that steam-exploded bamboo pulp started mass loss at lower temperature compared to bamboo internode meal. The thermal softening temperature of lignin prepared from steam-exploded pulp was much lower than that of lignin prepared from extract-free bamboo meal. This suggests that intermonomer linkages of lignin, especially β-aryl-ether linkage which is the major intermonomer linkage of lignin, were cleaved during steam explosion treatment resulting in low molecular weight phenolic compounds. The cleavage of β-aryl-ether intermonomer linkage of lignin was also confirmed by ozonation analysis.